The present invention provides two novel E. coli synthetic promoters, Syn 1 and Syn 2. Syn 1 and Syn 2 are two tight regulated synthetic promoters that control uninduced, leaky expression of proteins that are toxic and interfere with production of recombinant protein from an E. coli expression system.

The increased availability and identification of genes from human and other genomes has led to an increased need for efficient expression of recombinant proteins. The expression of proteins in bacteria is by far the most widely used approach for the production of cloned genes. For many reasons, expression in bacteria is preferred to expression in eukaryotic cells. For example, bacteria are much easier to grow than eukaryotic cells. More specifically, the availability of a wealth of sophisticated molecular genetic tools and thousands of mutants make E. coli, as an expression host, extremely useful for protein production. However, the high-level production of functional proteins in E. coli., especially those from eukaryotic sources has often been difficult. Inefficient translation initiation is the most common reason for poor expression (Schoner, B. E., et al., Methods Enzymol. 185:94-103, 1990).
Initiation sites where the enzyme binds to specific nucleotides sequences are known as promoters. By determining the nucleotide sequences of protected regions from numerous E. coli genes, a consensus sequence for the E. coli promoter has been identified. The most conserved sequence is a hexamer (−10 element) centered at about the −10 position from the transcription initiation site. The consensus sequence is TATAAT (SEQ ID NO:). Upstream sequences around −35 also have a region of sequence similarity, TTGACA (−35 element; SEQ ID NO:), which is most evident in efficient promoters. The distance separating the −35 and −10 elements is between 16 and 18 base pairs in 90% of promoters. The distance is critical for maintaining necessary structural conformation of the two sites for RNA polymerase binding.
Regulation of promoter regions in prokaryotic genes contain multiple binding sites for transcription factors. Interactions between and among regulatory proteins bound to promoter regions produce both positive and negative synergistic effects on gene expression. Regulation of lac operon of E. coli has been studied extensively and has become a model for negative control of gene expression at the level of transcription. (See, e.g., Muller-Hill B., Prog Biophys Mol. Biol., 30(2-3):227-52, 1975; and Sauer R T, Structure 4(3):219-22, 1996.) Transcription of the lac operon in Escherichia coli is repressed by the binding of Lac repressor (LacR) to lac operator O1, a pseudo-palindromic sequence centered 11 base pairs downstream of the transcription start. Repressors appear to inhibit transcription by either steric hindrance preventing the binding of DNA polymerase to the promoter, or by preventing the transition of the closed state of the promoter to the open state. The lac repressor exists as a tetramer, and full repression of the wild-type lac promoter by wild-type LacR requires the presence of at least two other operator sequences that must not only be in close proximity to the lac operator O1, i.e. located at base pair 401 and 92 for the auxiliary operators O2 and O3, respectively, but the operator sequences must also be present on the same side of the DNA helix. LacR mutants lacking the C-terminal heptad repeat are only capable of dimer formation, yet still repress, albeit at a much reduced level. Repression of the lac promoter by the mutants is comparable to repression by tetrameric LacR when both auxiliary operators are not present. For a general review, see, Muller-Hill B. Curr Opin Microbiol. 1(2):145-51, 1998.
Ideal promoter systems for overproducing recombinant proteins in E. coli should: (1) provide strong expression of cloned genes; (2) function only under inducing conditions; and (3) have a simple method of induction so that large-scale operation is possible. However, while the available repertoire of E. coli expression systems usually produce high levels of the corresponding cloned gene products, in many cases synthesize substantial levels of cloned gene products in uninduced or repressed conditions. Generally, these systems include controllable expression vectors based on the strong inducible promoter, tac and T7. Both promoter systems have only one lac operon site to regulate the target gene expression. Full repression of these two strong promoters has been difficult to achieve. Furthermore, the leaky basal expression of some toxic proteins can have a detrimental impact on cell growth and viability.
Despite advances in the expression of recombinant proteins in bacterial hosts, there exists a need for improved methods for higher yields for protein production.

Methods for enhancing expression of recombinant proteins


A computer assisted/implemented method for developing a classifier for classifying communications includes roughly four stages, where these stages are designed to be iterative: (1) a stage defining where and how to harvest messages (i.e., from Internet message boards, ews groups and the like), which also defines an expected domain of application for the lassifier; (2) a guided question/answering stage for the computerized tool to elicit the user's criteria for determining whether a message is relevant or irrelevant; (3) a labeling stage where the user examines carefully-selected messages and provides feedback about whether or not it is relevant and sometimes also what elements of the criteria were used to make the decision; and (4) a performance evaluation stage where parameters of the classifier training are optimized, the best classifier is produced, and known performance bounds are calculated. In the guided question/answering stage, the criteria are parameterized in such a way that (a) they can be operationalized into the text classifier through key words and phrases, and (b) a human-readable criteria can be produced, which can be reviewed and edited. The labeling phase is oriented toward an extended Active Learning framework. That is, the exemplary embodiment decides which example messages to show the user based upon what category of messages the system thinks would be most useful to the Active Learning process.

The present invention is a computer assisted/implemented tool that allows a non machine learning expert to build text classifiers. The present invention is also directed to the task of building Internet message relevancy filters.
The full end-to-end process of building a new text classifier is traditionally an expensive and time-consuming undertaking. One prior approach was to divide the end-to-end process into a series of steps managed by people with different levels of expertise. Typically, the process goes as follows: (1) a domain expert/programmer/machine-learning expert (DEPMLE) collects unlabeled communications (such as, for example, text messages posted on an Internet message board); (2) the DEPMLE writes a document describing the labeling criteria; (3) hourly workers with minimal computer expertise label a set of communications; (4) a data quality manager reviews the labeling to ensure consistency; and (5) the DEPMLE takes the labeled communications and custom-builds a text classifier and gives reasonable bounds on its accuracy and performance. This process typically takes several weeks to perform.
Traditional text mining software simplifies the process by removing the need for a machine learning expert. The software allows a tool expert to provide labeled training communications to a black box that produces a text classifier with known bounds on its accuracy and performance. This approach does not cover the complete end-to-end process because it skips entirely over the cumbersome step of collecting the communications and labeling them in a consistent fashion.
The traditional approach for labeling data for training a text classifier presents to the user for labeling, sets of randomly-selected training communications (un-labeled communications). Some of the user-labeled communications (the "training set") are then used to "train" the text classifier through machine learning processes. The rest of the user-labeled communications (the "test set") are then automatically labeled by the text classifier and compared to the user-provided labels to determine known bounds on the classifier's accuracy and performance. This approach suffers in two ways. First, it is inefficient, because better results can be achieved by labeling smaller but cleverly-selected training and test sets. For example, if a classifier is already very sure of the label of a specific unlabeled training example, it is often a waste of time to have a human label it. The traditional approach to solving this problem is called Active Learning, where an algorithm selects which examples get labeled by a person. The second problem with human labeling is that it is inaccurate. Even the most careful labelers make an astonishingly high number of errors. These errors are usually quite pathological to training a classifier. For example, when building message relevancy filters, a very significant fraction of time may be spent relabeling the messages given by a prior art Active Learning tool.

Method for developing a classifier for classifying communications


A hand-off method for reducing probability of call disconnection during hand-off in a digital personal communication service (PCS) system, comprising the steps of: forming a link path between a plurality of gateway communication interconnection networks (GCINs) by using interprocess communication (IPC) to connect base station controllers (BSCs) to each other; allocating a high capacity IPC node board assembly (HINA) address for distinguishing between the GCINs in order to perform the hand-off by means of the interprocess communication between the various GCINs; and handing-off a call by using the HINA address and a link path between the GCINs, in response to a hand-off request.

1. Field of the Invention
The present invention relates to a mobile radio communication system and, in particular, to a hand-off method in a digital personal communication service (PCS) system adopting a code division multiple access (CDMA) system.
2. Description of the Related Art
Referring to FIG. 1, a conventional hard hand-off method in a digital PCS system according to the prior art is shown. In this conventional digital PCS system, interprocess communication (IPC) is unavailable since, as illustrated in FIG. 1, there are no link paths formed between the plurality of gateway communication interconnection networks (GCINs) comprising the system. As a result, a hand-off procedure between the GCINs or between local communication interconnection networks (LCINs) is achieved by using a hard hand-off path (denoted as P1) between mobile switching centers (MSCs), with the hard hand-off path being interlocked with the MSC. A hand-off algorithm for providing such a hard hand-off path, however, results in a high probability of call disconnection, since it must perform many processing steps. Specifically, the probability that the call will be disconnected during the hand-off process (for call interruptions over 100 msec) is approximately 50%, which is relatively high.
One of the main causes for this disconnection problem is because the hard hand-off between the MSCs adopts a break-and-make method hand-off method. The break-and-make hand-off method involves temporarily disconnecting the call during processing for over 100 msec, during which time the MSC searches for a Base Transceiver System (BTS) having a stronger RSSI (received signal strength indication) signal of a mobile station at a new cell boundary. Consequently, the conventional hard hand-off method results in a high probability of call disconnection.

Hand-off method in a personal communication service system


A polycarbonate/polyester resin formulation has enhanced impact resistance and comprises a polycarbonate resin, a polyester resin, flakes having a desired coloration, and a modifier selected to enhance the impact strength of the molded resin.

This invention relates to a modified polycarbonate-polyester composition containing special-effect colorants and articles molded from such resin compositions.
Polyester resins derived from terephthalic acid and reactive derivatives thereof, such as dimethyl terephthalate, and alkanediols have been known for some time and have become important constituents for moldable compositions. Workpieces molded from such polyester resin compositions, alone, or combined with reinforcements, offer a high degree of surface hardness and abrasion resistance, chemical resistance, and high gloss. Polyester resins are blended with other carefully selected resins to improve impact strength, as well as tensile strength, modulus and distortion temperature. For example, polyesters are blended with aromatic polycarbonates as set forth in Kawase et al, U.S. Pat. No. 3,953,539.
Impact modified polycarbonate/polyester resins are excellent materials for applications requiring high impact, chemical resistance, and appealing aesthetic. In order to improve the appearance, special effect additives have been utilized as colorants. U.S. Pat. No. 5,510,398 to Clark et al relates to a highly filled, extruded polyalkylene terephthalate resin, a polycarbonate resin, a filler, a stabilizer, and a non-dispersing pigment to give the extruded thermoplastic material a speckled surface appearance. Column 5, lines 35 to column 6, line 61, describes impact modifiers. U.S. Pat. No. 5,441,997 to Walsh et al describes the use of impact modifiers in conjunction with polycarbonate/polyester compositions having a barium sulfate, strontium sulfate, zirconium oxide, or zinc sulfate filler. U.S. Pat. No. 5,814,712 to Gallucci et al describes a glycidyl ester as an impact modifier, and optionally other impact modifiers, for a polycarbonate/polyester resin. U.S. Pat. No. 4,264,487 to Fromuth et al describes aromatic polycarbonate, acrylate-based core-shell polymer, and aromatic polyester.
The following patents relate to metallic type pigments. WO 99/02594 which describes the use of rectangular aluminum flakes in Nylon compositions. U.S. Pat. No. 5,091,010 and EP 0 426 446 relate to the aesthetics of molded articles containing flakes. These references do not address mechanical performance concerns which are addressed by the present invention.
Among the problems to be solved when utilizing polycarbonate/polyester resins and particles and pigments to produce special color effects are those related to composition coloring and those related to producing a very bright, metallic reflective sparkle appearance in the molded articles while retaining impact strength. The use of special visual effect colorants in combination with unpreferred impact modifiers may to be detrimental to physical properties such as notched Izod impact. Although various impact modifiers are known in the prior art, the prior art is deficient in addressing the problem of enhancing the impact properties of polycarbonate/polyester resins having special effect colorants.
A polycarbonate/polyester resin formulation which has enhanced impact resistance comprises flakes having a coloration and/or metallic gloss, and a modifier selected to enhance the impact strength of the molded resin.
In a process for preparing the polycarbonate/polyester resin molding formulation, a desirable flake which is robust under compounding and molding conditions, has desirable color and aesthetics, and is compatible with blend components is selected. A compatible impact modifier is selected for enhancing the impact properties of the molded resin
It is desirable that the flakes display a bright, reflective sparkle or reflective metallic gloss appearance rather than appearing dull. It is further desirable that the look and consistency of the finished product can be controlled.
In a preferred embodiment of the present invention, a molding composition and molded articles which, based on the total weight of the composition, consist essentially of (a) from 10 to 90 weight percent of a polyester resin; (c) from 90 to 10 weight percent of an aromatic polycarbonate resin; (d) an effective amount of an modifier selected to enhance the impact strength of a molded resin, preferably a core-shell modifier having a butadiene-based copolymer rubber substrate with a methacrylate containing graft or an ABA triblock modifier with A polymeric units from styrene or derivatives thereof and B polymeric units from butadiene or derivatives thereof, and (e) a sufficient amount of a flakes for imparting a desired special visual effect, where the impact modifier enhances the impact strength of a molded composition as compared to a molding composition absent the modifier with the notched Izod impact strength preferably being at least about 6 ft.lbs./in., and more preferably at least 9 ft.lbs./in., according to ASTM test D256.
The most preferred molding compositions are MBS modified compositions with low temperature and room temperature impact strength.
According to another embodiment an effective amount of a random, block, and graft copolymers of vinyl aromatic compounds and conjugated dienes may be utilized to enhance the impact strength at higher temperatures.
The blend compositions combine appealing aesthetics, chemical resistance, and high impact properties and will be useful in molded article applications where this combination of properties is desirable.
Thermoplastic polymer blends containing flakes, such as metal or mica, typically drop significantly in notched Izod impact properties if they are not properly impact-modified. Not all impact modifiers are effective for retaining impact properties upon addition of metallic or pearlescent pigments. For example, the notched Izod values of EMA-GMA modified polycarbonate/poly(butylene terephthalate) (PC/PBT) blends can drop from 16 ft.lbs./in. to 2 ft.lbs./in. upon addition of as little as 0.8 weight percent metal flakes. According to the preferred embodiments of the present invention, methacrylate-butadiene-styrene (MBS) modified PC/PBT blends retain average notched Izod values above 6 ft.lbs./in., and more typically above 9 ft.lbs./in., at room temperature in the presence of metal flakes. The EMA-GMA glycidic impact modifiers are described in U.S. Pat. No. 5,814,712 to Gallucci et al.
The polyester resin component comprises structural units of the following formula:
wherein each R1 is independently a divalent aliphatic, alicyclic or aromatic hydrocarbon or polyoxyalkylene radical, or mixtures thereof and each A1 is independently a divalent aliphatic, alicyclic or aromatic radical, or mixtures thereof. Examples of suitable polyesters containing the structure of the above formula are poly(alkylene dicarboxylates), liquid crystalline polyesters, and polyester copolymers. It is also possible to use a branched polyester in which a branching agent, for example, a glycol having three or more hydroxyl groups or a trifunctional or multifunctional carboxylic acid has been incorporated. Furthermore, it is sometimes desirable to have various concentrations of acid and hydroxyl end groups on the polyester, depending on the ultimate end-use of the composition.
The R1 radical may be, for example, a C2-10 alkylene radical, a C6-12 alicyclic radical, a C6-20 aromatic radical or a polyoxyalkylene radical in which the alkylene groups contain about 2-6 and most often 2 or 4 carbon atoms. The A1 radical in the above formula is most often p- or m-phenylene, a cycloaliphatic or a mixture thereof. This class of polyester includes the poly(alkylene terephthalates) and the polyarylates. Such polyesters are known as illustrated by the following patents:
U.S. Pat. Nos. 2,465,319 2,720,502 2,727,881 2,822,348 3,047,539 3,671,487 3,953,394 4,128,526
Examples of aromatic dicarboxylic acids represented by the dicarboxylated residue A1 are isophthalic or terephthalic acid, 1,2-di(p-carboxyphenyl)ethane, 4,4xe2x80x2-dicarboxydiphenyl ether, 4,4xe2x80x2 bisbenzoic acid and mixtures thereof. Acids containing fused rings can also be present, such as in 1,4- 1,5- or 2,6- naphthalenedicarboxylic acids. The preferred dicarboxylic acids are terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid, cyclohexane dicarboxylic acid or mixtures thereof.
The most preferred polyesters are poly(ethylene terephthalate) (xe2x80x9cPETxe2x80x9d), and poly(1,4-butylene terephthalate), (xe2x80x9cPBTxe2x80x9d), poly(ethylene naphthanoate) (xe2x80x9cPENxe2x80x9d), poly(butylene naphthanoate), (xe2x80x9cPBNxe2x80x9d) and (polypropylene terephthalate) (xe2x80x9cPPTxe2x80x9d), and mixtures thereof. Other preferred polyesters include cycloaliphatic polyesters such as poly(1,4-cyclohexylenedimethylene 1,4-cyclohexanedicarboxylate) (xe2x80x9cPCCDxe2x80x9d), made from 1,4-cyclohexandimethanol, dimethyl 1,4-cyclohexanedicarboxylate, and/or derivatives thereof (see U.S. Pat. Nos. 5,986,040 and 5,939,519) which has recurring units of the formula:
Also contemplated herein are the above polyesters with minor amounts, e.g., from about 0.5 to about 5 percent by weight, of units derived from aliphatic acid and/or aliphatic polyols to form copolyesters. The aliphatic polyols include glycols, such as poly(ethylene glycol) or poly(butylene glycol). Such polyesters can be made following the teachings of, for example, U.S. Pat. Nos. 2,465,319 and 3,047,539.
The preferred poly(1,4-butylene terephthalate) resin used in this invention is one obtained by polymerizing a glycol component at least 70 mol %, preferably at least 80 mol %, of which consists of tetramethylene glycol and an acid or ester component at least 70 mol %, preferably at least 80 mol %, of which consists of terephthalic acid, and polyester-forming derivatives therefore.
The polyesters used herein have an intrinsic viscosity of from about 0.4 to about 2.0 dl/g as measured in a 60:40 phenol/tetrachloroethane mixture or similar solvent at 23xc2x0-30xc2x0 C. Preferably the intrinsic viscosity is 1.1 to 1.4 dl/g. VALOX Registered TM 315 polyester is suitable for this invention.
The polyester resin component is blended with a polycarbonate resin. Polycarbonate resins useful in preparing the blends of the present invention are generally aromatic polycarbonate resins. Typically these are prepared by reacting a dihydric phenol with a carbonate precursor, such as phosgene, a haloformate or a carbonate ester. Generally speaking, such carbonate polymers may be typified as possessing recurring structural units of the formula
wherein A is a divalent aromatic radical of the dihydric phenol employed in the polymer producing reaction. Preferably, the carbonate polymers used to provide the resinous mixtures of the invention have an intrinsic viscosity (as measured in methylene chloride at 25xc2x0 C.) ranging from about 0.30 to about 1.00 dl/g. The dihydric phenol which may be employed to provide such aromatic carbonate polymers are mononuclear or polynuclear aromatic compounds, containing as functional groups two hydroxy radicals, each of which is attached directly to a carbon atom of an aromatic nucleus. Typical dihydric phenols are: 2,2-bis(4-hydroxyphenyl)propane; hydroquinone; resorcinol; 2,2-bis(4-hydroxyphenyl)pentane; 2,4xe2x80x2-(dihydroxydiphenyl) methane; bis(2 hydroxyphenyl)methane; bis(4-hydroxyphenyl) methane; 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; fluorenone bisphenol, 1,1-bis(4-hydroxyphenyl) ethane; 3,3-bis(4-hydroxyphenyl) pentane; 2,2-dihydroxydiphenyl; 2,6-dihydroxynaphthalene; bis(4-hydroxydiphenyl)sulfone; bis(3,5-diethyl4-hydroxyphenyl)sulfone; 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane; 2,4xe2x80x2-dihydroxydiphenyl sulfone, 5xe2x80x2-chloro-2,4xe2x80x2-dihydroxydiphenyl sulfone; bis-(4-hydroxyphenyl)diphenyl sulfone; 4,4xe2x80x2-dihydroxydiphenyl ether; 4,4xe2x80x2-dihydroxy-3,3xe2x80x2-dichlorodiphenyl ether; 4,4-dihydroxy-2,5-dihydroxydiphenyl ether; and the like.
Other dihydric phenols which are also suitable for use in the preparation of the above polycarbonates are disclosed in U.S. Pat Nos. 2,999,835; 3,038,365; 3,334,154; and 4,131,575.
These aromatic polycarbonates can be manufactured by known processes, such as, for example and as mentioned above, by reacting a dihydric phenol with a carbonate precursor, such as phosgene, in accordance with methods set forth in the above-cited literature and in U.S. Pat. No. 4,123,436, or by transesterification processes such as are disclosed in U.S. Pat. No. 3,153,008, as well as other processes known to those skilled in the art.
It is also possible to employ two or more different dihydric phenols or a copolymer of a dihydric phenol with a glycol or with a hydroxy- or acid-terminated polyester or with a dibasic acid in the event a carbonate copolymer or interpolymer rather than a homopolymer is desired for use in the preparation of the polycarbonate mixtures of the invention. Branched polycarbonates are also useful, such as are described in U.S. Pat. No. 4,001,184. Also, there can be utilized blends of linear polycarbonate and a branched polycarbonate. Moreover, blends of any of the above materials may be employed in the practice of this invention to provide the aromatic polycarbonate.
One aromatic carbonate for use in the practice in the present invention is a homopolymer, e.g., a homopolymer derived from 2,2-bis(4-hydroxyphenyl)propane (bisphenol-A) and phosgene, commercially available under the trade designation LEXAN Registered TM from General Electric Company.
Branched polycarbonates may be utilized and are prepared by adding a branching agent during polymerization. These branching agents are well known and may comprise polyfunctional organic compounds containing at least three functional groups which may be hydroxyl, carboxyl, carboxylic anhydride, haloformyl and mixtures thereof. Specific examples include trimellitic acid, trimellitic anhydride, trimellitic trichloride, tris-p-hydroxy phenyl ethane, isatin-bis-phenol,tris-phenol TC (1,3,5-tris((p-hydroxyphenyl)isopropyl)benzene),tris-phenol PA (4(4(1,1-bis(p-hydroxyphenyl)-ethyl)alpha, alpha-dimethyl benzyl)phenol),4-chloroformyl phthalic anhydride, trimesic acid and benzophenone tetracarboxylic acid. The branching agent may be added at a level of about 0.05-2.0 weight percent. Branching agents and procedures for making branched polycarbonates are described in U.S. Pat. Nos. 3,635,895; 4,001,184; and 4,204,047 which are incorporated by reference.
All types of polycarbonate end groups are contemplated as being within the scope of the present invention.
Preferably the thermoplastic resin composition comprises an aromatic polycarbonate resin present at a level of from 10 to 90 percent by weight based on the total weight of the material, and a polyester resin present at a level of from 10 to 90 percent by weight based on the total weight of the thermoplastic resin composition, and more preferably the aromatic polycarbonate resin is present at a level of from 15 to 80 percent by weight based on the total weight of the composition, and most preferably present at a level of from 20 to 70 percent by weight based on the total weight of the composition. Preferably the polyester resin is present at a level of from 15 to 80 percent by weight based on the total weight of the thermoplastic resin composition, and more preferably is present at a level of from 20 to 70 percent by weight based on the total weight of the composition.
As indicated above, polyesters are typically prepared using metal catalysts which remain in the polyester product. Catalyst may include organic or inorganic compounds of cobalt, tin, antimony, zinc, titanium, magnesium, calcium, manganese, gallium, germanium, sodium, lithium, and the like. Titanium compounds, such as tetraalkyl titanates, are frequently used. The preparation of polyesters employing these metallic catalysts are described, for example, in U.S. Pat. No. 4,401,804 which is incorporated herein by reference. The residues of metal catalysts may cause transesterification between the polyester and polycarbonate.
A catalyst quencher may be used to deactivate metal catalyst residues. For instance, quenchers such as phosphorus acid, phosphoric acid and phosphites or phosphonites have been included in compositions comprising polyester and/or polycarbonate in order to improve the thermal stability of the composition. Compositions quenched with these additives may have unacceptable hydrolytic stability. When polyesters having epoxy functionality are included in a blend with polycarbonate, preferred catalyst quenchers are suitable metal phosphates, metal acid phosphates, metal acid pyrophosphates and metal polyphosphates for enhancing hydrolytic stability of the resulting molded article.
Suitable quenchers include metal acid phosphates, metal acid pyrophosphates and metal pyrophosphates, each being embraced by the general formula
MzxHyPnO3n+1
wherein M is a metal, xe2x80x9cxxe2x80x9d is a number ranging from 1 to 12, and xe2x80x9cyxe2x80x9d is a number ranging from 1 to 12, xe2x80x9cnxe2x80x9d is a number in the range of 1 to 10, xe2x80x9czxe2x80x9d is a number in the range of 1 to 5, and the sum of xz+y is equal to n+2.
The metal acid pyrophosphates of this invention preferably comprise metals from Group 1A of the Periodic Table of Elements, particularly, sodium and potassium. Suitable pyrophosphates embraced by the formula above include Na3HP2O7, K2H2P2O7, KNaH2P2O7,MgH2P2O7 and NaH2PO4. The preferred metal acid pyrophosphate for use in the compositions of this invention is sodium dihydrogen pyrophosphate, i.e., Na2H2P2O7.
The catalyst quencher preferably is present in the composition in the range of about 0.005 parts to about 5.0 parts by weight of the polyester component and most preferably from about 0.1 parts to about 2.0 parts.
The above-mentioned acid phosphates and pyrophosphates may be mixed with the polymers by any suitable means. Since most phosphates are solids, they can be most expeditiously mixed with the resin either as a precompounded concentrate or directly into the melt, e.g., in an extruder.
The metal acid phosphates and pyrophosphates preferably will have particle diameters of less than 75 microns, more preferably less than 50 microns, and most preferably less than 20 microns. If the particles have a diameter equal to or greater than 75 microns, the compositions containing the metal acid pyrophosphates may have reduced impact strength.
Additional quenchers suitable for this invention include Group IB and Group IIB metal phosphate salts such as calcium phosphate and zinc phosphate.
Hydrates and mixtures of the above salts also are suitable as quenchers for the composition of this invention. Reference to any of the above salts, thus, also are meant to refer to the hydrates and/or mixtures containing those salts. Preferred hydrates include dihydrates and tetrahydrates.
Preferred catalyst quenchers are monosodium phosphate, monopotassium phosphate, zinc acid phosphate and calcium acid phosphate.
As an additional resin component, an effective amount of an impact modifier is used for enhancing the impact strength of the polyester blends in the presence of special effect additives.
Preferred impact modifiers have polymer units of a low glass transition rubbery component in combination with polymeric units derived from vinyl aromatic compounds, acrylate compounds, alkylacrylate compounds or derivatives. Preferably the amount of impact modifier utilized is from about 5 to about 20 percent by weight based on the total weight of the resin molding composition.
To maintain ductility of a molded resin at temperatures on the order of minus ten degrees Centigrade, the preferred impact modifiers are core-shell type impact modifiers having a rubbery core comprising a polymer derived from butadiene or n-butyl acrylate and a shell comprising a polymer derived from a vinylaromatic compound, a vinylcyanide compound, or an alkyl methacrylate compound; preferably the shell is derived from methacrylate alone or in combination with styrene. Especially preferred grafted polymers are the core-shell polymers of the type available from Rohm and Haas, for example Paraloid EXL3691. Also present in the first stage are cross linking monomers and graft linking monomers. Examples of the cross linking monomers include 1,3-butylene diacrylate, divinyl benzene and butylene dimethacrylate. Examples of graft linking monomers are allyl acrylate, allyl methacrylate and diallyl maleate.
Core-shell copolymers, method of making core-shell copolymers and the use of core-shell copolymers as impact modifiers in combination with polycarbonate are described in U.S. Pat. Nos. 3,864,428 and 4,264,487.
Suitable core-shell copolymers are those that include a rubbery core that has a glass transition temperature (xe2x80x9cTgxe2x80x9d) below about minus 30xc2x0 C., preferable below minus 40xc2x0 C., and that comprises repeating units derived from one or more monoethylenically unsaturated monomers such as acrylate monomers, e.g. butyl acrylate, and conjugated diene monomers, e.g., butadiene and a rigid xe2x80x9cshellxe2x80x9d that has a Tg of greater than or equal to about 40xc2x0 C. and that comprise repeating units derived from a monoethylenically unsatuated monomer, e.g., methyl methacrylate.
Another, preferred impact modifier which contains units derived from butadiene in combination with a vinyl aromatic compound comprises ABA triblock copolymers, especially those comprising styrene based blocks and butadiene or isoprene based blocks. As compared to the previously discussed core-shell impact modifiers, the block copolymer impact modifiers lack low temperature ductility properties. The conjugated diene blocks may be partially or entirely hydrogenated, whereupon they may be represented as ethylene-propylene blocks or the like and have properties similar to those of olefin block copolymers. Examples of triblock copolymers of this type are polystyrene-polybutadiene-polystyrene (SBS), hydrogenated polystyrene-polybutadiene-polystyrene (SEBS), polystyrene-polyisoprene-polystyrene (SIS), poly (xcex1-methylstyrene)-polybutadiene-poly(xcex1-methylstyrene) and poly(xcex1-methylstyrene)-polyisoprene-poly(a-methylstyrene).
Particularly preferred triblock copolymers are available commercially as Kraton D(copyright), and KRATON G(copyright) from Shell. KRATON Polymers and compounds with an unsaturated rubber midblock constitute the KRATON D series (styrene-butadiene-styrene, SBS and styrene-isoprene-styrene, SIS) while those with a saturated midblock make up the KRATON G series (styrene-ethylene/butylene-styrene, SEBS and styrene-ethylene/propylene-styrene, SEPS). Both D- and G- series polymers are elastic and flexible. The KRATON G-series polymers are preferred for weather resistance due to increased oxidation resistance.
The molding composition includes flakes for imparting a desired visual effect, where, together with the impact modifier, the impact strength of the molded composition as compared to a molding composition absent the impact modifier has enhanced impact resistance. The flakes which ranging in size between about 17.5 and about 650, preferably from about 30 to about 300 microns are used in loading of 0.3 to 7 weight percent, with about 0.5 to about 5.0 weight percent being preferred. The flakes are preferably mineral or metal flakes. The preferred mineral flakes are mica flakes. The term flakes is intended to include thin particles including thin film, foil, or platelets which typically have a reflective and/or metallic appearance. Preferred metals are based on metals of Group I-B, III-A, IV, VI-B and VIII of the periodic table. Examples of these metals include aluminum, bronze, brass, chromium, copper, gold, iron, molybdenum, nickel, tin, titanium, zinc and the like. A xe2x80x9ccornflakexe2x80x9d type or corrugated irregularly shaped planar flake of aluminum or bronze is may be utilized, although a xe2x80x9csilver dollarxe2x80x9d type or a circular planar type of flake may also be utilized.
Aluminum flakes produce a satiny silver luster. In general, smaller particle sizes tend to have greater opacity and hiding power with a grayish effect, while larger flake sizes show greater brightness and reflectivity with increased metallic sparkle. Based on the size, concentration, and method of processing, various special visual effects may be obtained such as a pearlescent, metallic sparkle, metallic luster, or angular metamerism effect
Glitter is a special type of aluminum pigment produced from foil. The foil, rolled to gauges of less than 0.001 inch, is cut into square, rectangular or hexagonal shapes in sizes from 0.008 to 0.125 inch and typically coated with a transparent epoxy lacquer to halt oxidative dulling of the foil. Glitter, with its large particle sizes, can produce discrete highlights of metallic sparkle.
Gold bronzes are actually brasses--alloys of copper and zinc with a small amount of aluminum to reduce oxidation. The range of gold colors is produced by varying proportions of major alloy components. The green gold contain 70 percent copper, and color becomes redder as the percentage of copper is increased; 90 percent copper produces pale gold; deep gold is made by controlled oxidation of the alloys. Gold bronzes are usually utilized in flake form, with coarser grades giving more brilliance. Copper must be utilized with care, however, as it is susceptible to heat, moisture and corrosives.
Lubricants such as ethylene bis stearamide, butyl stearate, glycerin or mineral oils or the like are sometimes included in the binder formulation, and may or may not be compatible with other blend components.
Other additional ingredients may include antioxidants, and UV absorbers, and other stabilizers. Antioxidants include i) alkylated monophenols, for example: 2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl-4,6-dimethylphenol, 2,6-di-tert-butyl-4-ethylphenol, 2,6-di-tert-butyl-4-n-butylphenol, 2,6-di-tert-butyl-4-isobutylphenol, 2,6-dicyclopentyl4-methylphenol, 2-(alpha-methylcyclohexyl)-4,6dimethylphenol, 2,6-di-octadecyl-4-methylphenol, 2,4,6,-tricyclohexyphenol, 2,6-di-tert-butyl-4-methoxymethylphenol; ii) alkylated hydroquinones, for example, 2,6-di-tert-butyl-4-methoxyphenol, 2,5-di-tert-butyl-hydroquinone, 2,5-di-tert-amylhydroquinone, 2,6-diphenyl octadecyloxyphenol; iii) hydroxylated thiodiphenyl ethers; iv) alkylidene-bisphenols; v) benzyl compounds, for example, 1,3,5-tris-(3,5-di-tert-butyl-4-hydroxybenzyl)-2,4,6-trimethylbenzene;
vi) acylaminophenols, for example, 4-hydroxy-lauric acid anilide; vii) esters of beta-(3,5-di-tert-butyl-4-hydroxyphenol)-propionic acid with monohydric or polyhydric alcohols; viii) esters of beta-(5-tert-butyl-4-hydroxy-3-methylphenyl)-propionic acid with monohydric or polyhydric alcohols; vii) esters of beta-(5-tert-butyl-4-hydroxy-3-methylphenyl) propionic acid with mono-or polyhydric alcohols, e.g., with methanol, diethylene glycol, octadecanol, triethylene glycol, 1,6-hexanediol, pentaerythritol, neopentyl glycol, tris(hydroxyethyl) isocyanurate, thiodiethylene glycol, N,N-bis(hydroxyethyl) oxalic acid diamide. Typical, UV absorbers and light stabilizers include i) 2-(2xe2x80x2-hydroxyphenyl)benzotriazoles ii) 2-Hydroxybenzophenones, and 2xe2x80x2-hydroxy4,4xe2x80x2-dimethoxy derivative, and iii) esters of substituted and unsubstituted benzoic acids for example, phenyl salicylate, 4-tert-butylphenyl-salicylate, octylphenyl salicylate, dibenzoylresorcinol, bis-(4-tert-butylbenzoyl)-resorcinol, benzoylresorcinol, 2,4-di-tert-butyl-phenyl-3,5-di-tert-butyl-4-hydroxybenzoate and hexadecyl-3,5-di-tert-butyl-4-hydroxybenzoate. Phosphites and phosphonites stabilizers, for example, include triphenyl phosphite, diphenylalkyl phosphites, phenyldialkyl phosphites, tris(nonyl-phenyl)phosphite, trilauryl phosphite, trioctadecyl phosphite, distearyl pentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl)phosphite, diisodecyl pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite tristearyl sorbitol triphosphite, and tetrakis(2,4-di-tert-butylphenyl)4,4xe2x80x2-biphenylene diphosphonite.
Dyes or pigments may be used to give a background coloration. Dyes are typically organic materials that are soluble in the resin matrix while pigments may be organic or inorganic compounds or complexes which are typically insoluble in the resin matrix. These organic dyes and pigments include the following classes and examples: furnace carbon black, titanium oxide, phthalocyanine blues or greens, anthraquinone dyes, scarlet 3b Lake, azo compounds and acid azo pigments, quinacridones, chromophthalocyanine pyrrols, halogenated phthalocyanines, quinolines, heterocyclic dyes, perinone dyes, anthracenedione dyes, thioxanthene dyes, parazolone dyes, polymethine pigments and others.
The flakes are incorporated into the resin composition by uniformly mixing into the desired resin composition. It is important that the flakes be stable at processing temperatures. Stability is desired at temperatures on the order of about 400, preferably at 500, and even more preferably 550 degrees F. Unstable flakes should be avoided.
The compositions of the present invention includes dyes and stabilizers which are added in effective amounts to impart the desired properties on the compositions of the present invention for the specific application.
The resin comprises less than 5 percent by weight additional ingredients which include the previously mentioned light stabilizers which added ingredients contribute to desirable properties previously mentioned and additional, important properties of good mechanical properties, color stability, oxidation resistance, good flame retardancy, good processability, i.e. short molding cycle times, good flow, and good insulation properties.
The method of blending the compositions can be carried out by conventional techniques. One convenient method comprises blending the resins and other ingredients in powder or granular form, extruding the blend and comminuting into pellets or other suitable shapes. The ingredients are combined in any usual manner, e.g., by dry mixing or by mixing in the melted state in an extruder, on a heated mill or in other mixers. An alternative method of blending can comprise preparing a preblend of the polyesters and then adding the other ingredients to the preblend. For example, a preblend of the resins and stabilizer can be fed into the upstream port of an extruder with addition of the other ingredients such as glass fibers in a downstream port of the extruder. In another embodiment, the various compounds can be precompounded, pelletized and then molded. Precompounding can be carried out in conventional equipment. For example, a dry blend of the ingredients can be fed into a single screw extruder, the screw having a long transition section to insure proper melting. Alternatively, a twin screw extrusion machine can be fed with the resins and other additives at the feed port and reinforcements fed downstream. In either case, a generally suitable machine temperature will be from about 450xc2x0 F. of about 575xc2x0 F. The precompounded composition can be extruded and cut or chopped into molding compounds, such as conventional granules, pellets, etc. by standard techniques. The compositions can be molded in any equipment conventionally used for thermoplastic compositions. For example, good results will be obtained in an injection molding machine, with conventional cylinder temperatures, e.g., 500xc2x0 F., and conventional mold temperatures, e.g., 150xc2x0 F.
To enhance the weatherability of a molded article, a clear coat may be used to cover outer surfaces that are exposed to weathering. The desirable coating is clear or substantially transparent so that the luster and the special visual effect of the molded article is remains visible. The coating may be a mono or multi-layered coating. Base coatings applied directly adjacent the substrate may be act as a primer coat to enhance the adhesion of an outer layer. Clear coats are commercially available from Red Spot(trademark) coatings and may comprise a polyester, polyurethane, or acrylic type coating where an isocyanate reactive material reacts with an alcohol functionality to produce a desired coating. Commercially available coatings from Red Spot(trademark) coatings include the 281 SL Series and the 206 LE Series.

Special visual effect polycarbonate-polyester composition


A low pressure die casting powdery mold releasing agent according to this invention consists of a granulated or powdery mixture of a lubricant, an organic polymer and a metal soap; wherein the lubricant is coated with the organic polymer or the metal soap. Therefore, the mold releasing agent allows productions of castings of high quality, in a squeeze casting work, with good workability and without worsening environmental situations.

1. Industrial useful field
This invention relates to a mold releasing agent which is used by being sprayed onto inside surfaces of a molding die in a low pressure die casting work.
2. Prior art
A low pressure die casting method is being utilized widely in manufacturing various parts for automobile and electrical equipment because cast parts of high precision can be manufactured continuously and in large quantities by this method. And, in this low pressure die casting method, a mold releasing agent is used in order to prevent a molding die from direct contact with molten metal for avoiding seizure and for improving release of products from dies.
The low pressure die casting mold releasing agent is generally classified into two principal groups: a water soluble mold releasing agent and a water insoluble mold releasing agent. Among these agents, the water insoluble mold releasing agent includes problems from a standpoint of safety because of its large danger due to smoke and flammability so that the water soluble mold releasing agent is being used frequently. The water soluble mold releasing agent is generally composed of mold releasing base materials such as water, mineral oil etc., to which silicon oil, synthetic or natural wax, fats and oils, fatty acid ester etc. for use as surface active agent or extreme pressure providing agent, are annexed.
3. Problems to be solved by the Invention
Incidentally, with a progress of low pressure die casting technology in recent years, there has been an increasing demand for a mold releasing agent to obtain products of high quality with better workability. However, it has become impossible to satisfy this demand by using the water soluble mold releasing agent. Namely, the water soluble mold releasing agent has included problems that control of die temperature has been difficult due to its water solubility and there has been a high possibility of defects arising in product insides due to remaining water. Further, there has been a problem that liquid-waste treatment has become required for prevention of water pollution to induce increases in various expenses for plant and equipment investment. Therefore, a strong demand for a mold releasing agent of a new type has arisen.

Method for low pressure die casting with low pressure die casting powdery mold releasing agent


In a field emission type image display panel, plural cathode electrodes are formed in a stripe shape on a first substrate and each having emitters for field emission. Cathode lead-out electrodes supply signals to the cathode electrodes. Plural patch-like gate electrodes are arranged in a matrix form over the plural cathode electrodes and insulated from the plural cathode electrodes. Gate lead-out electrodes are led out along spaces between adjacent two rows in rows formed of patch-like gate electrodes substantially perpendicular to the cathode electrodes, each of the gate lead-out electrodes being connected to the patch-like gate electrodes in adjacent two rows in a zigzag arrangement and every other gate electrode. A second substrate is spaced from the first substrate a predetermined distance apart. Plural patch-like anode electrodes are arranged on the second substrate, the plural anode electrodes respectively confronting the plural patch-like gate electrodes in a matrix form. Fluorescent materials are formed over the plural patch-like anode electrodes, for displaying an image. Anode electrodes are led out along spaces between adjacent two rows of anode electrodes substantially perpendicular to the cathode electrodes, each of the anode lead-out electrodes being connected to anode electrodes in adjacent two rows in a zigzag arrangement and every other anode electrode.

(1) Field of the Invention
This invention relates to a field emission type image display panel and a method of driving the same.
(2) Description of the Related Art
When the electric field at a surface of a metal or semiconductor is as large as 10.sup.9 V/m, electrons pass through the potential barrier because of the tunnel effect, thus emitting out in a vacuum at room temperatures. This phenomenon is called field emission. The cathode emitting electrons utilizing the principle is referred to as a field emission type cathode.
Recently, flat emission type field emission cathodes each formed of an array of micron-size field emission type cathodes (hereinafter, referred to as FEC) have been able to be manufactured fully using semiconductor machining technology.
The structure of a field emission cathode called a Spindt type cathode is schematically shown in FIGS. 13(a) and 13(b).
FIG. 13(a) is a perspective view showing a FEC fabricated using the semiconductor micromachining technology. FIG. 13(b) is a cross-sectional view showing the FEC, taken along the line A--A in FIG. 13(a).
Referring to FIGS. 13(a) and 13(b), a cathode electrode 102 is formed on the substrate 101 by using vapor deposition. Cone emitters 105 are formed on the cathode electrode 102. Gate electrodes 104 are formed over the cathode electrode 102 where the cone emitters 105 are not formed, via the insulating layer 103 of silicon dioxide (SiO.sub.2). The cone emitters 105 are respectively positioned in the round holes formed in the gate electrode 104 and the insulating layer 103.
That is, the tip of each cone emitter 105 is viewed in the hole opened in the gate electrode 104.
The cone emitters 105 are fabricated at pitch intervals of less than 10 microns, using micromachining technology. Thus, several ten to several 100 thousands of FECs can be fabricated on a single substrate 101.
Since the distance between the gate electrode 104 and the tip of the emitter 105 can be set in the order of submicrons, the emitter 105 can emit electrons caused by the field emission when a small voltage of several tens of volts is applied between the gate electrode 104 and the cathode electrode 102.
The above-mentioned FEC can be made as a flat field emission cathode. It has been proposed to apply the flat field emission cathode to a flat color display panel. The cross-section of the color image display panel is partially shown in FIG. 14.
In FIG. 14, columns of cathode electrodes 102 are arranged in a stripe from on the first substrate 101 of glass. Stripe-like gate electrodes 104 are arranged perpendicularly to the columns of the stripe-like cathode electrodes 102. The cone emitters 105 are arranged on the cathode electrodes 102 at the intersections.
The tips of the emitters 105 located at each of the intersections where the columns of the gate electrodes 104 intersects the columns of the cathode electrodes 102 point upward. The insulating layer 103 isolates the cathode electrodes 102 from the gate electrodes 104. Holes are formed in the insulating layer 103 to emit electrons.
The second substrate 110 of glass is arranged so as to confront the first substrate 101. A sheet of anode electrode 111 is formed on the nearly whole surface of the second substrate. Red fluorescent material 112, green fluorescent material 113, and blue fluorescent material 114 in stripe form are formed on the anode electrode 111 so as to confront the stripes of the cathode electrodes 102 respectively.
In order to display color images on the color display panel, the gate electrodes 104 are sequentially scanned and driven one by one while R, G, and B image data corresponding to one selected line of the gate electrode 104 are supplied to the cathode electrodes 102. Then, when all the gate electrodes 104 are sequentially scanned and selectively driven, a full color image for one frame is displayed on the second substrate 110.
However, in the color image display panel, it has been assumed that electrons emitted from the emitter 105 formed on the cathode electrode 102 reach the anode electrode 111, with a divergent angle of about 30.degree.. Hence, the problem is that electrons which reach the anode electrode 111 with a divergence of a considerable degree may glow a different color fluorescent material adjacent to the anode electrode 111. As a result, the color image displayed is blurred.
In order to solve the above-mentioned problem, the present applicant proposed a field emission type image display panel that can display color images with no blurring, by focusing electrons emitted from the emitter 105 (refer to the Japanese Patent Application (Tokugan-Hei) No. 7-114134).
FIG. 15 is a top view partially illustrating a field emission type image display panel proposed above.
In the field emission type image display panel of FIG. 15, stripe-like cathode electrodes 102 shown with chain lines are arranged on the first glass substrate (not shown). The cathode lead-out electrodes C1, C2, . . . , Cm are respectively connected to the stripe-like cathode electrodes 102.
Patch-like gate electrodes 120 are formed over the cathode electrodes 102 through an insulating layer (not shown) while they are arranged corresponding to respective pixels. As previously described, an emitter array is formed on the patch-like gate electrodes 120.
The second substrate (not shown) is arranged so as to confront the cathode electrodes 102. An anode electrode 111, shown with broken lines, is formed over the entire surface of the second substrate. R fluorescent, G fluorescent, and B fluorescent materials are formed on the anode electrode 111 so as to confront the respective patch-like gate electrodes 120. In FIG. 15, symbols associated with gate electrodes 120 represent colors emitted from the fluorescent material.
The patch-like gate electrodes 120 corresponding to G, B, and B pixels odd numbered in the (i) line (rows) are connected to the gate lead-out electrode GTi-1. The gate electrodes 120 corresponding to remaining R, G, and B pixels even numbered in the (i) line are connected to the gate lead-out electrode GTi.
Furthermore, the patch-like gate electrodes 120 corresponding to G, B, and R pixels odd-numbered of the (i+1) line is connected to the gate lead-out electrode GTi. The patch-like gate electrodes 120 corresponding to remaining R, G, and B pixels even-numbered of the (i-1) line is connected to the gate lead-out electrode GTi-1 (not shown). In a similar manner, in the gate lead-out electrodes GT1 to GTn, the patch-like gate electrodes 120 of an upper line (row) as well as the patch-like gate electrodes 120 of a lower line (row) are connected to each gate lead-out electrode in a zigzag pattern and every other gate electrode.
The gate lead-out electrodes GT1 to GTn are sequentially scanned and driven. For example, when the gate lead-out electrode GTi is scanned, the R, G, and B pixels even-numbered of the (i) line (hatched) and the G, B, and R pixels odd-numbered of the (i+1) line are driven.
When image data are correspondingly input to the cathode electrodes C1, C2, . . . , Cm respectively confronting the patch-like gate electrodes 120, an image can be displayed on the anode substrate. When the gate lead-out electrodes GTi-1 and GTi+1 not driven are set to a low level potential, preferably to the ground level, the adjacent patch-like gate electrodes 120 on the sides of each of the patch-like gate electrodes 120 (hatched) are driven to a low level potential. This allows electron beams emitted from the patch-like gate electrodes 120 driven to be focused.
As described above, in the field emission type image display panel using patch-like gate electrodes, electron beams emitted from the emitters 105 can be focused. However, in recent years, there have been strong demands for high brightness, high resolution, field emission type image display panels. It is required to more focus electrons emitted from the emitter 105.

Field emission type image display panel and method of driving the same


A dust proof electric switch is provided for use in a dynamoelectric machine employing a centrifugal acuator having a terminal board with a cup formed therein in which a fixed contact point and terminal are mounted. A pivotable switch arm having a contact point attached thereto is mounted to the arm and extends above and cantilevered across the terminal board so that pressure on the switch arm from the centrifugal acuator causes the contact points to touch thereby closing the circuit. An open ended, resilient, flexible boot is affixed to the cup and extends upward between the terminal board to snuggly abut the switch arm and completely enclose the contact points when they are touching and when they are apart thereby protecting the contact area from dust and debris as well as containing sparks within the boot. The terminal board contains stops which serve to maintain alignment of the switch arm.

This invention relates to switch assembly structure for electrical machinery and more particularly to an improved switch assembly which protects the contact points of the switch from external contaminants which can be utilized in a number of types of electrical machinery, for example, in a radial arm saw, in conjunction with conventional centrifugal actuators for dynamoelectric machines. While the invention is described in detail with respect to the saw application, those skilled in the art will recognize the wider applicability of this invention.
As is well known in the art, a number of dynamoelectric machines, for example, capacitor start and split phase induction motors, utilize a first winding combination for the "starting" condition of a motor operation, and a second winding combination for the "run" condition of a motor operation. These motors include a stator assembly and a rotor assembly, the rotor assembly including a shaft and the stator assembly including a plurality of windings. The selective energization of the windings is used to generate suitable forces for rotating the rotor assembly in both "start" and "run" conditions. As also known in the art, a centrifugal actuator mounted on the shaft is utilized to move a switch arm of a switch assembly mounted on a terminal board between a first position and a second position to cause selective electrical energization of the winding combinations.
These types of switch assemblies are known to the art. For example, U.S. Pat. No. 4,034,173 to Crow et al., discloses a starting switch assembly integrally formed with a terminal connection board which is adapted to be actuated by a conventional centrifugal actuator. U.S. Pat. No. 4,686,401 to Gehrt, et al., discloses a starting switch assembly integrally formed with a terminal connection board also designed to selectively engage and disengage contacts for electrical machinery such as the windings for dynamoelectric machines.
Generally, however, motor switches of the prior art have obvious drawbacks in some applications. First, there are certain applications for dynamoelectric machines that place these machines in environments having contaminants in the air to which the machine is exposed. For example, switches are utilized in motors which drive table saws or radial arm saws. When employed in a radial arm saw, the dynamoelectric machine is exposed to contaminants such as sawdust in the air. Often, these machines exposed to high concentrations of saw dust and other particles in the air are plagued by motor failure. Motor failure occurs because the electrical switch used in association with the open motor fails due to dust accumulation between the switch contact points.
As previously explained, the motors employed in the radial arm saws are either split-phase or capacitor start induction run motors that conventionally employ centrifugal actuators that control the operations of the starting circuit of the motor. When the motor is not running, the actuator closes the switch so that an auxiliary or start winding is connected to a source of electrical energy while the actuator disconnects the start winding as the motor reaches operating speed. Conventional switch structures of the prior art employed in this environment often malfunction because the contaminants that enter the switch and accumulate between the contact points do not allow the switch to close.
A number of attempts have been made in prior art to eliminate switch failure problems. In particular, attempts have been made to enclose the starting switch contacts in order to protect them from the environment. While this has reduced the failure rate of open motors used in the above applications, it has not completely solved the problem. For example, U.S. Pat. No. 4,414,443 to Gehrt, discloses an environmentally protected switch construction preventing foreign matter from affecting switch contact operation. However, the protective structure in this patent requires the use of a series of elements including a first washer, a soft, compressible washer inboard of the first washer, a third metallic washer positioned inboard of the pliable washer, and a spring positioned inboard of the third metallic washer, to create a suitable arrangement that protects the contacts from outside contaminates. This protective construction requires a plurality of parts, and is sensitive to alignment.
U.S. Pat. No. 4,922,066 to Crow et al., discloses an environmentally protected switch for dynamoelectric machines requiring the use of a metallic cap which surrounds the contact point affixed to the movable switch arm, a rubber-like boot affixed to the second contact post extending upward and interconnected with the metallic cap which surrounds the first contact point. As long as the boot adheres to the cap and the second contact post, the integrity of the enclosed environments for the switch contacts is maintained. However, since the integrity of the environment for the contact switch is dependant upon the alignment of the first metal cap and the rubber boot, as well as the alignment of the rubber boot on the second contact post, the metal cap and the rubber boot can become misaligned thereby destroying the integrity of the environmental seal. Even where misalignment is not a problem, the construction is relatively expensive to produce.


A wedge-ribbed belt supports an elevator car by underlooping and engages a drive pulley of a drive mounted at the head of an elevator shaft. The belt has a running surface facing the drive pulley with a plurality of ribs and grooves extending in parallel in a longitudinal direction of the belt. The ribs and grooves can be triangular-shaped or trapezium-shaped in cross section. A plane of the drive pulley is arranged vertically and at right angles to a car wall at a counterweight side of the elevator car and approximately in a middle of a car depth with a vertical projection of the drive pulley onto the counterweight side being outside a vertical projection of the counterweight side. A part of a vertical projection of the drive motor is superimposed on the vertical projection of the counterweight side of the elevator car.

The present invention relates to elevator systems having flat belts supporting the elevator car.
Elevator systems of the kind according to the present invention usually comprise an elevator car and a counterweight, which are movable in an elevator shaft or along free-standing guide devices. For producing movement, the elevator system comprises at least one drive with at least one respective drive pulley which by way of support and drive means supports the elevator car and the counterweight and transmits the necessary drive forces to these.
The support or the drive means are termed support means in the following description.
In the case of conventional elevator systems, steel cables with a round cross-section are usually used as support means. However, flat belt-like support means are increasingly used for more modem systems.
An elevator system with a flat-belt-like support means is shown in the PCT Patent Application WO 99/43593. In the embodiment illustrated therein by FIG. 6 the elevator system comprises a drive motor which is arranged in the elevator shaft above the elevator car and acts by way of at least one drive pulley on at least one flat support means strand by which an elevator car and a counterweight arranged on the side thereof can be moved upwardly and downwardly. The flat-belt-like support means in that case runs from one side of the drive pulley horizontally to a first deflecting roller, runs around this through 90°, then extends downwardly along the car wall at the counterweight side, loops by 90° around each of two car support rollers mounted on respective sides below the elevator car and runs upwardly along a car wall remote from the counterweight to a first support means fixing point present in the upper region of the elevator shaft. From the other side of the drive pulley the support means runs horizontally to a second deflecting roller, runs around this by 90°, then extends downwardly to the side, which is at the car side, of the periphery of a counterweight support roller, loops around this by 180° and runs vertically to a second support means fixing point in the shaft head region.
Such an elevator system has, thanks to the use of a flat-belt-like support means, the advantage that drive pulleys as well as deflecting and support rollers can be used with substantially smaller diameters than would be required in the case of the use of conventional wire cables. Due to the smaller drive pulley diameter the drive torque required at the drive pulley is reduced, whereby a drive motor with smaller dimensions can be used. Thanks to the generally smaller support means pulley diameter it is possible to realize simpler and space-saving elevator systems.
However, the elevator systems described in the WO 99/43593 publication have certain disadvantages.
As a consequence of the small drive pulley diameter, and because in the case of use of flat belts as support means known measures for improving the traction capability, for example undercutting of the cable grooves at drive pulleys for round support means, are not usable, the problem can arise in the case of a relatively large weight ratio between fully laden and empty elevator car that the traction forces transmissible between drive pulley and flat-belt-like traction means are not sufficient.
Moreover, it is known that in the case of use of flat-belt-like support means without profiling of the running surface substantial problems with the lateral guidance of the support means on the drive pulley, deflecting rollers and the support rollers arise. Experience has shown that there is a risk that the support means so strongly rubs against the lateral boundary discs usually present at the drive pulleys, deflecting rollers and support rollers that the support means are damaged.


This disclosure provides a transmission method and a first communication device. The method includes: transmitting, by a first communication device, a target reference signal that belongs to a first type of reference signal in a case that the first communication device receives indication information from a second communication device and the indication information indicates transmission of the first type of reference signal, where a reference signal sequence of the first type of reference signal is generated based on a first characteristic.

In new radio (NR) mobile communication systems of the related art, in a case that transmission precoding (also referred to as a discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) waveform) is employed on a physical uplink shared channel (PUSCH) or a physical uplink control channel (PUCCH), low peak-to-average power ratios (PAPR) of demodulation reference signals (DMRS) are higher than PAPRs of data symbols and uplink coverage performance is poor because a DMRS sequence is generated using a PAPR sequence (also referred to as a Zadoff-Chu (ZC) sequence) or a pseudo-noise (PN) sequence.

Transmission method and first communication device


A dual clutch transmission which has a first clutch, actuated by a first hydraulic cylinder, a second clutch, actuated by a second hydraulic cylinder, shift devices for shifting gears, which are actuated by respective hydraulically operated cylinders, and a hydraulic energy source for supplying the hydraulic cylinders and the hydraulically operated cylinders with hydraulic energy. The hydraulic energy source has a first pump, a second pump and an electric drive driving the second pump.

The invention relates to a dual clutch transmission comprising a first clutch which is actuated by a first hydraulic cylinder, a second clutch which is actuated by a second hydraulic cylinder, a plurality of shift devices for shifting gears which are actuated by one respective hydraulic cylinder, and comprising a hydraulic energy source for supplying the hydraulic cylinders and the hydraulically operated cylinders with hydraulic energy.
It is known to shift shifting gears, in particular dual clutch transmissions, hydraulically, as well as to actuate the two clutches hydraulically.
It is the object of the invention to provide an advanced dual clutch transmission, adapted in particular to the requirements of advanced drive engineering.

Hydraulic control for a dual clutch transmission

Luk Lamellen und Kupplungsbau Beteiligungs KG


An electrical connector (1) includes a dielectric housing (2), a number of power terminals (4) at one end of the housing, signal terminals (5) and solder pad contacts (6) disposed at the other end of the housing opposite to the power terminals. The housing includes a base portion (20) and a bottom portion (21) and defines a number of passageways (212, 213, 215) extending through the bottom portion. The terminals (4, 5) received in the passageways (212, 213) each have a contact portion (40, 50) and a solder foot (41, 51). The solder pad contacts and the power terminals have a width greater than the signal terminals. The solder pad contacts are upwardly inserted into the passageways (215) of the base portion from the bottom portion and each includes a retention portion (60) for interfering with the base portion and a solder foot (61) extending beyond the bottom portion. Use of wide power terminals and wide solder pad contacts at the other end of the housing provides balanced solder attachment to a pcb. The solder pad contacts are used solely for securement to the pcb.

1. Field of the Invention
The present invention is related to an electrical connector, and more particularly to a board-mounted electrical connector for use in a notebook computer.
2. Description of Related Art
An electrical connector mostly comprises a dielectric housing and a plurality of conductive terminals received in the dielectric housing. The plurality of conductive terminals generally include power terminals, signal terminals and grounding terminals. Generally, the power terminal has a width greater than the signal terminal and the grounding terminal for the electrical current that the power terminals conduct is larger than that of the signal terminals. However, because the width of the power terminal is added, the soldering portion of the power terminal has higher soldering intensity than the signal terminal. When the power and signal terminals are distributed asymmetrically in the electrical connector and the electrical connector is mounted onto a printed circuit board, the electrical connector will have unbalanced soldering intensity. Consequently, the soldering area between the signal terminal and the printed circuit board is easily broken off when the electrical connector repeatedly connects with/detaches from a complementary connector or due to an accidental external force, thereby resulting in deformation of the electrical connector and even leading to break the electrical interconnection between the electrical connector and the printed circuit board and thus affect normal signal transmission.
Hence, it is requisite to provide an electrical connector having balanced soldering intensity and improved connector reliability to overcome the above-mentioned disadvantages of the related art.

Board-mounted electrical connector with balanced solder attachment to a circuit board


A pneumatic steel bar binding machine mechanism to bind two or more column-shaped steel bars together, or specifically, a machine to bind the steel frames inside the concrete framework in construction works, characterized in a pneumatic mechanism and a spiral twister that press steel staples in the shape of reversed-U onto the steel bars to be bound, before the spiral twister is driven to twist the two ends of the steel staple into a twisted rope, to secure the steel bars.

The invention relates to a pneumatic steel bar binding machine mechanism to bind two or more column-shaped steel bars together, particularly the steel framework contained inside concrete structures in construction works, the components in a main unit 10 include an air valve chamber 30, a cylinder chamber 50, a pneumatic motor 70, a steel staple 20, a staple cartridge 40 and a spiral twister 80 and a J-mechanism 60.
[Prior Art]
Conventionally, the steel bars regularly used in the construction of concrete structures are fastened by tying iron wires directly around them with hands and/or pliers. Such a binding process can be sophisticated and troublesome, as well as time and labor consuming. Slight negligence on the operator""s part will result in improper binding efficiency, causing potential risks to the steel bars that may loosen. At the present, some construction workers may use an electrical steel bar binding machine. The motor in such a binding machine, however, may overheat after an extended period of use. Furthermore, direct sunshine often adds to its burden. Also, because the electrical cord of the steel bar binding machine is very long, a worn or torn electrical cord may result in leak of electrical conductance and cause danger in its operation. Besides, the steel bar binding machine itself is quite heavy, its binding speed is slow and inefficient, which can cause increased working costs.
It is therefore the objective of this invention to provide a pneumatic steel bar binding machine mechanism with high efficiency, low labor strength, and safe operation, which will quickly and automatically push out a steel staple tightly against the steel bars, to enable firmer binding point, and since the pressing force and binding force are automated, its binding efficiency can be assured.
In accordance with the foregoing, a pneumatic steel bar binding machine is provided.

Pneumatic steel bar binding machine mechanism


A cooling steam system for a steam cooled gas turbine is configured such that a main stream of exhaust from a high pressure turbine is branched from a line leading to a reheater, and supplied as cooling steam for a high temperature moving blade and a high temperature stationary blade of the gas turbine, and the cooling steam is then recovered into an inlet area or an intermediate area of the reheater; whereby the bottoming side and the steam cooled side can be operated under preferred conditions without adverse influence on the bottoming side.

This invention relates to a gas turbine system in which a high temperature moving blade and a high temperature stationary blade of a gas turbine are steam cooled.
FIG. 2 is a schematic system diagram of a conventional general gas turbine and a bottoming cycle.
A high temperature moving blade and a high temperature stationary blade of a gas turbine 51 are cooled with bleed air 53 from a compressor 52. A system in which steam from a bottoming cycle is used for cooling of a moving blade and/or a stationary blade of a gas turbine and returned again to the bottoming cycle has not bee put to practical use.
Outlet steam from a high pressure turbine 54 of a bottoming cycle totally enters a reheater 55, where it is heated to an appropriate temperature and supplied to an intermediate pressure turbine. A system with this constitution achieves a high efficiency.
In the drawing, a zone enclosed with a one-dot chain line represents a bottoming cycle, in which the numeral 56 denotes an intermediate pressure turbine, 57 a low pressure turbine, 58 a condenser, 59 a feed water pump, and 60 an exhaust gas boiler.
With the existing equipment, as noted above, cooling of the gas turbine is usually performed with air. Recently, however, the idea of using steam from the bottoming cycle for cooling of the gas turbine instead of air cooling has been introduced in accordance with the high temperature operation of the gas turbine.
As described above, steam cooling methods for the gas turbine have been introduced here and there. However, all of these methods are still at a trial-and-error stage, and involve many unresolved issues in order to emerge as actual machines.
Take, as an example, a steam cooled gas turbine system in which a moving blade or a stationary blade of a gas turbine is cooled with steam supplied from the bottoming cycle side, and this steam is recovered and returned again to the bottoming side for an improvement in efficiency or output. In this system, a considerable amount of steam that has so far flowed in the bottoming flows into the gas turbine during movement between the gas turbine and the bottoming cycle. Thus, a marked influence is exerted on each other.

Cooling steam system for steam cooled gas turbine


Apparatus for accurately determining the width of a traveling document in which respective groups of LEDs are disposed along a line extending transversely of the path of document travel inwardly from points spaced by a distance greater than the maximum document width. The groups of LEDs and respective strip photodiodes associated therewith are disposed on opposite sides of the path so that a document travelling along the path partially blocks respective LEDs of said groups. The LEDs are sequentially energized one by one from one end of the group to the other. The completely unblocked energized LEDs are counted and the percent blocked of the partially blocked LED is determined to permit an accurate width measurement to be calculated.

Many systems are known in the prior art for testing currency notes to determine the genuineness thereof and to discriminate between notes of different denominations. Most of these devices involve reading indicia printed on a face of the note and comparing it with stored data. Some of the devices involve a rough measurement of a dimension of the note in the direction of travel thereof through the device.
A few devices of the prior art make a determination of the dimension of a note in a direction transverse to the direction of travel thereof. For example, Pauli et al U.S. Pat. No. 4,435,834 discloses an arrangement in which the note passes through the space between an illuminating means and a row of photodiodes. The number of darkened photodiodes is counted and divided by the number of diodes per unit width to obtain a measure of width which is compared with maximum and minimum values.
Favre U.S. Pat. No. 4,298,807 discloses an arrangement in which the document passes by an array of sixty photodiodes corresponding to the maximum width of the document to be inspected. These photodiodes are arranged in groups of four for analog multiplexing. The outputs of the multiplexing circuit are applied to analog to digital converters and averaging circuits and to a common comparator circuit to give information as to the dimension of a note.
While the systems just described afford a rough indication of the width of a document being inspected, the measurement afforded thereby is not as accurate as is desirable in many instances. For example, in certain countries respective denominations of currency are differentiated by width. Known systems do not afford as accurate a width measurement as is necessary effectively to discriminate between notes of different denominations.


A process for sequestration of carbon dioxide comprising the following steps: (a) dispersing solid waste material comprising calcium oxide and a calcium-comprising mixed oxide in water to dissolve at least part of the calcium oxide and to form calcium oxide-depleted solid waste material in a calcium hydroxide solution; (b) separating the calcium hydroxide solution from the calcium oxide-depleted solid waste material; (c) converting the calcium hydroxide in the separated calcium hydroxide solution in precipitated calcium carbonate; and (d) contacting an aqueous slurry of the calcium oxide-depleted solid waste material with carbon dioxide for mineral carbonation of the carbon dioxide to form carbonated solid waste material.

It is known that carbon dioxide may be sequestered by mineral carbonation. In nature, stable carbonate minerals and silica are formed by a reaction of carbon dioxide with natural silicate minerals:(Mg,Ca)xSiyOx+2y+xCO2→x(Mg,Ca)CO3+ySiO2 The reaction in nature, however, proceeds at very low reaction rates. The feasibility of such a reaction in process plants has been studied. These studies mainly aim at increasing the reaction rate.
At the internet site of the US department of energy, http://www.fetc.doe.gov/publications/factsheets/program/prog006.pdf, for example, is disclosed the reaction of finely ground serpentine (Mg3Si2O5(OH)4) or olivine (Mg2SiO4) in a solution of supercritical carbon dioxide and water to form magnesium carbonate.
In WO02/085788 is disclosed a process for mineral carbonation wherein particles of silicates selected from the group of ortho-, di-, ring, and chain silicates, are dispersed in an aqueous electrolyte solution and reacted with carbon dioxide.
An alternative for the use of natural minerals as starting material for carbon dioxide sequestration is the use of industrial waste materials that contain calcium-comprising mixed oxides such as calcium silicate or calcium iron oxide. Mineral carbonation of industrial waste materials such as steel slag has been proposed. In 'Accelerated carbonation of waste calcium silicate materials' by D. C. Johnson (ISSN 1353-114X), for example, it is disclosed that stainless steel slag, deinking ash, pulverised fuel ash are suitable feedstocks for a carbon dioxide sequestration process.
The use of steel slag for mineral carbonation would, however, be more attractive if valuable product streams could be recovered from the carbonation process.

Process for sequestration of carbon dioxide


Disclosed are agents for phase-adjusting or enhancing the amplitude of an endogenous melatonin secretion rhythm and for improving a circadian rhythm, as well as functional food containing such an agent, which may prevent or ameliorate various symptoms, such as sleep disorder or prolonged sleep latency. The agent contains whey as the active component.

People in the modern world tend to lead irregular lifestyle under the influence of recent advances and complication of technologies as well as fast-moving social situation. The advent of the 24-hour society has forced people into an irregular mode of life, which leads to circadian rhythm disorder, such as sleep disorder, or disorder of an endogenous melatonin secretion rhythm, which is a possible factor for the circadian rhythm disorder.
It has been confirmed that entrainment of a circadian rhythm is controlled in the suprachiasmatic nucleus (SCN) in the hypothalamus. A typical substance that is known to regulate a circadian rhythm controlled by the suprachiasmatic nucleus is melatonin (N-acetyl-5-methoxytryptamine) secreted mainly from the corpus pineale. Melatonin is a hormone synthesized from tryptophan through serotonin under the action of NAT (N-acetyltransferase) as a rate-limiting enzyme. This hormone is believed to be involved in introduction of photoperiodic information in photoperiodic mammals and exert an influence on reproduction, body weight, metabolic regulation, circadian rhythm control, as well as nervous and endocrine functions. Further, since the melatonin secretion level of the corpus pineale is low in the day time and high in the night time, melatonin is believed to be one of the sleep-modulatory substances.
It is known that the melatonin secretion rhythm in patients with sleep disorder or circadian rhythm disorder is different from that of healthy people in that the amplitude is decreased or the phase is either advanced or delayed.
For overcoming such disorders of a circadian rhythm or a melatonin secretion rhythm to treat or prevent sleep disorder, administration of exogenous melatonin has been proposed. For example, Patent Publication 1 reports that oral administration of melatonin from an external source to artificially regulate a melatonin rhythm has an effect on non-24-hour sleep-wake syndrome, jet lag syndrome, shift-work sleep syndrome, delayed sleep phase syndrome, or the like, accompanied by prolonged sleep latency, insomnia, waking in bad mood, jet lag, reverse of day and night, or the like.
However, the safety of melatonin products, including the side effect of exogenous melatonin products per se, has not been fully assured.
Patent Publication 2 proposes a composition for improving the quality of sleep, containing as the active component muramyl peptide prepared by hydrolysis from the cell wall of non-pathogenic lactic acid bacteria. However, the improvement in the quality of sleep taught in this publication is achieved by increasing the length of the non-REM sleep phase through induction of sleep by the immune system, so that this way of improving the quality of sleep is completely different from the improvement of the endogenous melatonin secretion level.
Patent Publication 1: JP-08-502259-T
Patent Publication 2: JP-2003-517828-T

Functional food for ameliorating endogenous melatonin secretion rhythm and functional food for ameliorating circadian rhythm


A package for at least two objects includes RFID bridge antennas, having RF antenna elements, for wirelessly communicating data between a tag associated with each object and a reader. An electromagnetic carrier signal transmitted by the reader antenna is received by one of the RF antenna element and retransmitted to the tag antenna by the other RF antenna element, increasing the distance over which the tag can communicate with the reader. Where the tag is attached to a packaged object, the RFID bridge antenna may be included in the package to allow wireless data communication between the tag and a reader. The reader may also be located external to the package. For example, one of the RF antenna elements may be attached to a label on the package, allowing data stored in the tag to be extracted by the external reader.

A common trend in machine design, particularly in the office equipment industry, is to organize a machine on a modular basis, wherein certain distinct subsystems of the machine are bundled together into modules which can be readily removed from the machine and replaced with new modules of the same or similar type. A modular design facilitates great flexibility in the business relationship with the customer. By providing subsystems in discrete modules, also known as "customer replaceable units" or CRUs, visits from a service representative can be made very short, since all the representative has to do is remove and replace a defective module. Actual repair of the module may take place remotely at the service provider's premises. Further, some customers may wish to have the ability to buy modules "off the shelf;" such as from an equipment supply store. Indeed, it is possible that a customer may lease the machine and wish to buy a supply of modules as needed. Further, the use of modules, particularly for expendable supply units (e.g., copier and printer toner bottles) are conducive to recycling activities.
In order to facilitate a variety of business arrangements among manufacturers, service providers, and customers, it is known to provide these modules with electronically-readable memory devices, also known as "customer replaceable unit monitors" or CRUMs, which, when the module is installed in the machine, enable the machine to both read information from the CRUM and also write information to the CRUM. The information read from, or written to, the CRUM may be used by the machine to perform various functions. For example, U.S. Pat. No. 6,016,409 entitled "System For Managing User Modules in a Digital Printing Apparatus", which is incorporated by reference herein in its entirety, describes various data that may be stored in a CRUM and various functions that may be performed using this data.
The use of CRUMs in a machine requires that the machine include a means for communicating data between the CRUMs and the control circuitry resident in the machine. This may be accomplished wirelessly. For example, U.S. Pat. No. 6,377,764 issued Apr. 23, 2003 and entitled "Method and Apparatus for Communication, Without A Solid Medium, Among Control Boards in a Printing Apparatus," which is incorporated by reference herein in its entirety, describes a digital printing apparatus in which one or more modules has a board therein, which is able to communicate with another board within the apparatus by infrared or other wireless communication. In another example, U.S. Pat. No. 6,351,621 to Richards et al., describes a printer or copier having a removable module, such as a marking material supply module or a marking device module, that is provided with a CRUM. The non-volatile memory of the CRUM is accessed through a wireless interface, such as a radio frequency identification (RFID) system, which is also associated with the module. The memory can be accessed, through wireless means, either by the printer or copier itself or by an external device.
Wireless identification systems (e.g., RFID systems) typically include two sub-assemblies: a tag (also known as a transponder) and a reader (also known as an interrogator, transceiver, or coupler). The tag is typically attached to an object, and includes, among other components, an antenna and an integrated circuit (IC) device. Stored within the IC device is information related to the object to which the tag is attached. While this information usually includes identification data for the object, it may include other information related to, or used by, the object (e.g., tracking information, usage information, computer code, etc.). For example, the object may be a CRU and the tag may be a CRUM.
In operation, the antenna on the tag receives incoming data signals superimposed on a modulated carrier signal, which is provided by an antenna on the reader. In response to the incoming data signals, the tag superimposes data from the IC device onto the carrier signal by changing its own circuit impedance. In some tags, known as passive tags, the carrier signal is used to provide operating power for the tag. In other tags, known as active tags, at least some of the operating power for the tag is provided by a source other than the carrier signal (e.g., a battery).
The reader forms an interface between the tag and a host such as a computer. The reader generally includes an integrated circuit chip and associated circuitry that allows it to communicate with both the tag and the host computer. Typically, there is a predefined command set used by the host computer to control the reader, which passes the commands to the tag via the modulated carrier signal. The reader generates the modulated carrier signal to transmit data to the tag, and receives data from the tag by detecting the loading effects of the tag on the carrier signal.
Any given tag and reader combination will communicate data over a limited distance. For example, an RFID system that conforms to International Standards Organization (ISO) Standard 14443-2B (13.56 mega-Hertz (MHz)) is ideal for communicating over distances of between 0 millimeters (mm) to 30 mm. If a system is designed to operate in the mm to 20 mm range, it is unlikely this system will work in the 40 mm to 50 mm range. Problematically, it is unlikely that the designed communication range can be maintained at every desired point of access (e.g., during production, packaging, shipping, and installation). For example, when a CRU having an attached CRUM is packaged for shipping or storage, the distance between the CRUM within the package and a reader external to the package may be greater than the designed operating range. As a result, the CRUM must be removed from the package to place the reader close enough for data communication between the CRUM and reader.


A screw for use in an plasticating injection apparatus includes a plurality of interrupted primary flights. An outer surface of a primary valley is formed by the primary flights and features a plurality of plateaus. The plateaus span adjacent sections of the primary flights and define shallow levels between deeper levels of the primary valleys. This depth differential contributes to a turbulent mixing action which, along with the primary and secondary valleys, contributes to improve mixing action within a metering section of the screw. The primary flights are interrupted by secondary valleys which are of opposite hand to the primary valleys.

1. Field of Invention
This invention relates to the field of extruders and injection machines utilizing a rotatable screw within a heated barrel, and more specifically to a screw structure which improves mixing of the injection material while that material is within the barrel.
2. Description of the Related Art
Extruders and injection molding machines are well known. One of the common problems in the use of such a machine is the differences in the material properties of the material due to temperature differentials between points close to the inner surface of the barrel wall and points farther away. Because the barrel is heated, a temperature differential commonly exists across the material between these points. It is preferable that this temperature differential be minimized in order to avoid over heating the injection material or otherwise damaging its properties. One way to minimize such differential is to mix the resinous material while it is in the barrel.
Another common problem concerns molding of products utilizing resinous materials of different colors. When resinous materials of two or more colors are to be molded, any incomplete mixing of such resinous materials could mar the appearance of the finished molded product.
For these and other reasons, better mixing of resinous materials within extruder barrels has been desired within the industry.
Various methods of providing such mixing are known in the art. For example, in U.S. Pat. No. 3,006,029 to Saxton, an extruder mixing screw is disclosed having primary channels and minor channels. In addition, U.S. Pat. No. 5,035,509 to Kruder discloses a screw with a zig zag barrier for mixing within the mixing section of the screw. U.S. Pat. No. 5,071,256 to Smith et al. discloses a screw with barrier near the outlet end of the screw. Finally, U.S. Pat. No. 4,752,136 to Colby discloses a plasticating apparatus and rotating screw having at least two paths of different depths near an outlet end of the screw.
Although some of these screws are effective for their purpose, further improvements are desirable.
The present invention contemplates a new and improved plasticating apparatus and method which overcomes the foregoing difficulties and others while providing better and more advantageous overall results.