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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to biological detoxification of drain waters from high pH aqueous environments to remove high concentrations of soluble cyanides, thiocyanates, and toxic heavy metals.
2. Description of Prior Art
Heap leaching, in metallurgical mining terms, involves stacking crushed ore on impermeable liners. A cyanide solution is sprayed over this stockpile and permeates the ore particles. Cyanide causes gold, silver, copper, and other metals to be solubilized. Metals of economic interest are then recovered by conventional separation means.
Wastewaters from the cyanidation process contain high concentrations of free cyanide, metal complex cyanide, ammonia, and thiocyanate. These compounds form by chemical interaction between cyanide and sulfide which are commonly present in metal bearing ores. Cyanidation wastewaters are potentially toxic to aquatic organisms, wildlife, and human beings. Thus, cyanide complexes, heavy metals, and ammonia must be removed before discharge of these wastewaters into surface or ground waters serving as potential potable water sources, or into marine or fresh water habitats.
Several chemical treatment process for removal or detoxification of cyanidation process wastewaters have been employed. Conventional processes utilize ozonation; alkaline chlorination; chlorine dioxide; copper catalyzed hydrogen peroxide; sulfur dioxide/air; acidification, volatization, and reneutralization; evaporation; and sludge impoundment. These methods are limited in their capacity to remove highly concentrated cyanide on an economic basis.
Ozonation oxidizes free cyanides, weakly complexed metal cyanides, and thiocyanate, but fails to oxidize strongly complexed metal cyanides such as ferri- and ferro-cyanide. Ammonia, a by-product of cyanide or thiocyanide oxidation with ozone, is also not oxidized. At high levels, ammonia is toxic to humans and aquatic organisms. Ozone has limited solubility which results in poor treatment performance and a costly process.
Alkaline chlorination processes utilize chlorine compounds, e.g., chlorine gas, hypochlorite, or chlorine dioxide, which remove cyanides and precipitate metals at elevated pH. Iron complexed cyanides, ammonia, and chlorides are not removed. Thiocyanate oxidation may demand excessive chlorine and strict pH control is required for effective metals removal.
Copper catalyzed hydrogen peroxide processes, e.g., those described in U.S. Pat. No. 3,617,567 to Mathre, are becoming the preferred chemical process in the mining industry. These processes remove free and metal complexed cyanides through oxidation, including the ferri- and ferro-cyanides. However, both thiocyanate and ammonia remain. Metals are removed through precipitation. As with ozonation or chlorination, the large volumes of metal hydroxide sludges must be removed from the environment. The added copper catalyst is toxic to aquatic organisms at very low concentration and must be carefully removed before water discharge. Moreover, large amounts of expensive hydrogen peroxide are used, regardless of the cyanide concentration.
International Nickel Company's sulfur dioxide/air oxidation process, which is also copper catalyzed, is similar to other oxidative chemical processes. High sulfate effluent levels and large volumes of metal sludge are process drawbacks.
An acidification, volatilization, and reneutralization process utilizes strong acidic conditions to volatilize cyanides as hydrogen cyanide gas. The gas is trapped with a caustic soda solution. Metals are then concentrated into a hydroxide sludge. At present, the economics of this process are unfavorable in most situations.
Containment of wastewaters followed by evaporation is utilized in some arid areas. Residual sludges must be impounded or treated by other means as toxicity is concentrated from the solution into the sludge formed.
Biological treatment methods have been proposed for aerobic (requiring oxygen) and anaerobic (in the absence of oxygen) destruction of cyanides. The microorganisms Alcaligenes and/or Achromobacter were added to activated sludge to degrade nitriles and cyanides, see U.S. Pat. No. 3,756,947 to Fujii et al. U.S. Pat. No. 3,940,332 was issued to Kato et al. for the use of Nocardia to remove nitriles and cyanides from wastewaters. The genus Pseudomonas has produced species capable of decomposing hydrogen cyanide (U.S. Pat. No. 3,660,278 to Mimura). Multiple stage combinations of chemical and biological treatment systems are disclosed in U.S. Pat. Nos. 3,816,306 to Roy, and U.S. Pat. No. 4,188,289 to Besik.
Pseudomonas paucimobilis, see U.S. Pat. No. 4,461,834 to Mudder and Whitlock, is used in a full scale treatment facility as described in U.S. Pat. No. 4,440,644 to Mudder and Whitlock. That biological facility treats low concentration metal complexed cyanide wastewaters at near neutral pH. The bacterial strain Pseudomonas paucimobilis is described in Holmes et al. (1977) Int. J. Sys. Bacteriol. 27:133-146.
However, none of these methods provide an effective and economical means for treating heap leach pad wastewaters. These wastewaters are characterized by particularly high cyanide concentrations and high pH. The present invention provides methods and means for economical treatment of these highly polluted waters.
SUMMARY OF THE INVENTION
The biological treatment processes of the present invention remove free and metal complexed cyanides, and thiocyanate through oxidation, even at very high concentrations. Toxic heavy metals are absorbed and adsorbed within a biofilm produced by the biological process. This process has been adapted to and performs well at high cyanide concentrations (e.g., even above 100 mg/L) and high pH (e.g., as high as 10). Mixed cultures containing adapted strains of Pseudomonas are utilized to perform biological oxidation within the system. End products of oxidation include carbonates, sulfates, and nitrates. The pH is neutralized by, or metabolism of, intermediate reaction products. Nitrifying bacteria may also be used to remove ammonia.
The biological processes can be utilized alone or as a pretreatment or post-treatment process in conjunction with chemical processes.
In an exemplary process, treatment according to the present invention is performed by direct application of biomass to a heap leach pad. A more efficient exemplary treatment regime involves flushing contaminated heap leach wastewater from the heap leach pad. This wastewater is then treated biologically in a water treatment apparatus independent of the heap leach pad. Once treated, this biologically active water source can be recycled to further flush the heap leach pad. Active bacterial cells contained within the heap leach pad can continue the treatment. The final treated effluent may be suitable for land application.
Heap leach drainwaters may be of high pH (>10.0) due to agglomeration. Cement is used to clump fine particles into larger composite particles. Fine particles cause "blinding," or block flow through the ground ore. Agglomeration binds the fine particles into larger aggregates and reduces this "blinding" effect. Before biological treatment, phosphoric or sulfuric acid may be used to reduce pH to approximately 9.5-10.0. The optimum pH for the Pseudomonas culture is 7.5. Biological cyanide degradation efficiency decreases as pH increases above 7.5. However, degradation efficiency is still acceptable at a pH as high as 10.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention is a process to biologically detoxify residual wastewaters from high pH aqueous environments, particularly cyanidation heap leach pads.
The environments will usually also contain high concentrations of cyanide and other toxic substances. High pH and high cyanide concentrations are defined hereinafter with specific reference to the exemplary heap leach environments.
Cyanide extraction of crushed ores extracts gold, silver, copper, and othermetals from the heap leach pads. Once precious metals are extracted from heaped ores by cyanide dissolution the wastewaters from the spent pad posea long term environmental threat. These wastewaters typically have high concentrations of free cyanides, metal complex cyanide, ammonia, and thiocyanate. The biological processes of the present invention provide lowcost, efficient, and long term solutions to remediate this environmental threat. Treatment by the biological processes described herein equals or exceeds the performance of known chemical treatment processes. Biological sludge production is an order of magnitude less than chemical sludge volumes produced by chemical processes. The resulting biological sludges have long term activity or remedial capacity and nutrient value in the environment, in contrast to chemical sludges.
According to the present invention, organisms of the genus Pseudomonas are used to remediate the wastewaters. These organisms are adapted to tolerate, degrade, and detoxify free cyanides, metal complexed cyanides, thiocyanates, and heavy metals of moderate to high concentration. The wastewaters present an extremely hostile growth environment to the organisms, combining high levels of toxic compounds with a high pH. The aerobic biological populations consist of mixed cultures of species of Pseudomonas. The species used and relative populations of each species will depend upon process conditions and site-specificity. However species exposed to high cyanide concentrations will require high resistance to retain viability. This resistance is selected through controlled adaptation.
The heap leach wastewaters normally have high cyanide concentrations. Thus,the cultures used herein will be tolerant to cyanide levels of at least about 25 mg/L, normally at least about 45 mg/L, typically at least about 65 mg/L, and usually at least about 85 mg/L. The cyanide will be in the forms of free cyanide and metal complexed cyanide. These will be found in compounds, e.g., iron cyanide, copper cyanide, and free hydrogen cyanide.
Additional compounds to which tolerance is particularly important include ammonia, thiocyanate, arsenic, and heavy metals, e.g., copper, mercury, lead, and cadmium.
In addition to high cyanide concentrations, the heap leach wastewaters are often also very alkaline or basic, so the cultures must also be tolerant to conditions of elevated pH. The strains will normally be tolerant to a pH of at least about 7.5, typically of at least about 8.5, and usually of at least about 9.5.
To achieve required toxic compound tolerances, the cultures are subjected to selection. Genetic or developmental variants are selected for those which are naturally tolerant to those conditions. Pseudomonas cultures, such as P. aeruginosa, selected for cyanide acclimation studies are maintained in a liquid growth media consisting of metal complexed cyanides, e.g., at a concentration of about 15 mg/L, with thiocyanate and toxic heavy metals, e.g., at concentrations of about 120 mg/L and 4-6 mg/Lrespectively. The growth medium also contains nutrient inorganic salts as required for culture maintenance. The selection process is performed undera series of conditions of increased stringency to arrive at the desired tolerances.
As cyanide (CN - ) is degraded biologically, ammonia is produced. Toxic concentrations of cyanide may be expected to produce toxic concentrations of ammonia during degradative processes. Ammonia tolerant strains can be selected, or nitrifying bacteria in mixed culture are utilized to convert ammonia to nitrate. Exemplary nitrifying bacteria include Nitrobacter, Nitrosomonas, and others.
The end products of biological detoxification, e.g., degradation, of cyanides and thiocyanates include environmentally compatible compounds of bicarbonate, sulfate, and nitrate.
The microorganisms are contacted with the wastewaters in an appropriate manner for a sufficient period of time to achieve satisfactory detoxification. This time period will normally be at least about a quarterhour, typically at least about a half hour, usually at least about one hour, and preferably at least about two hours. To optimize capacity, shorter time periods will often be used, though longer times may provide greater efficiency.
Conventional biological digestion processes and hardware will be useful with these microorganisms. Conventional processes and equipment are described, e.g., in U.S. Pat. No. 4,461,834, which is incorporated herein by reference. The biomass may be utilized, e.g., as a suspended or attached growth system. Activated sludge systems utilize organisms suspended in solution. Rotating biological contactors (RBC's), trickling filters, and bio-towers utilize plastic, metal, ceramic, or natural media,e.g., river rock, to promote attached growth of biomass. In either system, the biological treatment is affected by mixed cultures which grow togetheras an aerobic flora which contacts the waters. Preferably, the dissolved organic matter in the water provides the nutrients for growth of the flora. The present invention provides aerobic mixed flora which metabolizethe cyanides and thiocyanates to environmentally acceptable byproducts, e.g., nitrates and sulfates.
A common method of biological treatment makes use of an activated sludge. This is a biologically active sediment produced by the repeated aeration and settling of sewage and/or organic wastes. The activated sludge comprises a mixture of bacteria, protozoa, and miscellaneous other forms of life. The types and numbers of the various organisms will vary with thetypes of nutrients present in the sludge and with the length of the aeration. The organisms within the activated sludge metabolize the polluting organic matter within the sludge and leave environmentally acceptable metabolites.
The activated sludge process typically involves aeration of suspended biological solids in a solution. Aeration is often achieved through submerged porous diffusers or by mechanical surface agitation. Typically, an aeration period of two to six hours is followed by a one to two hour period with no aeration to allow the solids to settle. These solids, whichcomprise the solids in the suspension together with the biological growth, are maintained in the aeration tanks to provide seed for continued biological treatment. Suspended solids are maintained at 1000 to 3000 mg/Lby appropriate solids removal at appropriate times. The removed solids are preferably non-toxic.
An alternative process for biological remediation uses attached growth processes. Attached growth processes in rotating biological contactors (RBC's), trickling filters, or bio-towers appear to perform better than activated sludge systems in treating waters with high cyanide and metals concentrations. Therefore, packed columns, e.g., a biofilter and a pilot scale RBC were selected test designs. See, e.g., Clark, J. W., Viessman, W., and Hammer, M. J. (1977) Water Supply and Pollution Control (3d Ed.) Harper and Row, New York, for general description of these attached growthapparatuses.
The design and manufacture of biofilters and rotating biological contactorsis well established. Standard references describing the parameters of interest and design of both processes and apparatus include, e.g., Clark, et al. (1977) Water Supply and Pollution Control which is incorporated herein by reference. Loading rates are based on biological oxidation demand (BOD) figures. Research data on sewage treatment is often relevant.Wastewater retention times are normally several hours with hydraulic loading rates based on gallons/day/ft 2 and mass load rates of pounds/day/ft 2 . The present system should sustain mass loading rates of at least about 5-10 gpdft 2 with 50 mg/L total oxanide.
Rotating biological contactors are generally electrically or air driven plastic media disks of high surface area, e.g., 100,000-150,000 ft 2 . These disks revolve at 0.5-1.5 revolutions per minute with the disk about 40% submerged in the wastewater. Supplemental air, e.g., high volume/low pressure, will often be added to support attachment of aerobic biomass.
Mixed cultures of Pseudomonas species are adapted to decreasing dilutions of wastewater from an operational heap leach pad. This acclimation period lasts 4-6 weeks and results in a maintenance culture established at 60-70 mg/L total cyanide concentration.
The biota selected at the Wood Gulch site was developed by utilizing existing biomass from the Homestake Wastewater Treatment Plant in Lead, S.D. This biomass was subjected to wastewater from Wood Gulch at about pH 9.5, at a temperature of about 60° F. Alkalinity was controlled at about 180 mg/L and phosphorus as Pi at about 0.8 mg/L. This selection continued for about 7 weeks. The resulting surviving biomass appears to beprimarily Pseudomonas species, though identification has not yet been completed. This acclimated culture serves as a "seed" source for subsequent testing.
The methods described herein may be used by themselves in a treatment process, or may be combined with other treatment methods, e.g., as a pre-treatment or post-treatment step. Different stages of the process may be combined, each stage containing a microorganism population selected forspecific remediation of different toxic compounds.
EXPERIMENTAL RESULTS
Wastewater tested consisted of drainwaters from a cyanidation process heap leach pad. Also, cyanide contaminated samples of ore from the leach pad were subjected to biological detoxification. Agglomeration, i.e., mixing cement products with fine ore particles to increase particle size, was utilized in the heap leach stockpile design. The pH of the drainwater was above pH 11.
Contaminants in the wastewater and bound to the ore particles included metal complexed cyanides, free cyanides, and thiocyanates.
Pilot testing of biological wastewater treatment processes consisted of attached growth to plastic media. Packed columns represented the biofilterconcept and a 2.0 meter pilot scale RBC represented the stationary contactor concept. Contaminated ore in columns was directly seeded with biological cultures to represent in-situ treatment of wastewaters within the leached stockpile.
Parameters selected for analysis were total cyanide, weak acid dissociable (WAD) cyanides, thiocyanate, ammonia, heavy metals, hardness, alkalinity, and pH. Total cyanide is the total of all metal complexed cyanides, hydrogen cyanide, and sodium cyanide. this is measured by standard ASTM methods, measuring total cyanides after distillation. See, EPA (1983) Methods for Chemical Analysis of Water and Wastes. Weak acid dissociable cyanides are metal complexed cyanides, e.g., copper, zinc, nickel cyanides, and hydrogen and sodium cyanide. The WAD cyanides are measured by ASTM methods. Thiocyanates are sulpher bound cyanide (SGN) and are measured by the ferric nitrate method (ASTM).
Ammonia levels are typically measured by use of an ion selective electrode (ASTM). Heavy metals, e.g., copper, nickel, zinc, cobalt, cadmium, and chromium are measured by atomic absorption methods (ASTM).
Hardness is the sum of calcium and magnesium concentrations, both expressedas CaCO 3 and MgCo 2 , in mg/L. They are both measured together using an EDTA titration method (ASTM). Alkalinity is a measure of the water capacity to absorb hydrogen ions without significant pH change (neutralization or buffering capacity) and is measured according to standardized sulfuric acid addition.
Analysis was in accordance with Methods for Chemical Analysis of Water and Wastes: EPA-600 4-79-020, 1983, NTI Springfield, Va. 22161; and Standard Methods for the Examination of Water and Wastewater: 17th Edition, 1989, American Public Health Association, Washington, D.C. 20005, each of which is hereby incorporated herein by reference.
EXPERIMENT 1
A trickling filter design was tested. Plexiglass columns of 6 inch diameterand 10 foot length were packed with contaminated ore or plastic pall rings.Ore particles were 1/2-3/4 inch size and loosely packed in the columns. Pall rings were Norton (Houston, Tex.) brand 5/8 inch plastic pall rings; 104 sq. ft. surface area per cubic foot volume. Hydraulic load rates to the packed columns were 1 to 3 gallons per day/ft 2 surface area.
A battery of five columns was used in the pilot test design. Column function was as follows:
Column 1: Cyanide contaminated ore was packed in the column to a depth of nine feet. Biological growth from the mixed species of Pseudomonas culturewas seeded to a depth of 3/8 inch on the upper surface of the ore media. Contaminated drain water was passed through the column at a flow rate of 4.0 ml/minute. Characterization of wastewater from the heap leach pad is given in Table 1.
TABLE 1______________________________________WASTEWATER CHARACTERIZATIONCONCENTRATION IN mg/L______________________________________Total CN 101.3 WAD CN* 73.4Thiocyanate 15.8 Ammonia-N 24.5Nitrite 3.88 Nitrate 7.0Sulfate 160.0 Phosphorus 1.4pH 11.8 Alkalinity-Total 406.0Hardness 140.0 Mercury 0.05Copper 6.46 Gold 0.10Iron 2.83 Lead 0.04Zinc 0.21 Cadmium 0.01Nickel 0.80 Chromium 0.60Silver 1.9 Arsenic 1.1______________________________________*WAD Cyanide is analyzed as Weak Acid Dissociable Cyanide, measured according to ASTM standards
Column 2: Cyanide contaminated ore was packed in the column to a depth of nine feet. No biological seed was added to the column. The hydraulic feed was 4.0 ml/minute or a hydraulic loading rate of 1.5 g/day/ft 2 . The effluent from column 2 becomes the feed source for column 4.
Column 3: 5/8" plastic pall rings form the packing for this column. Column packing is seeded with a mixture culture of Pseudomonas which is given 2 weeks before the beginning of this test to attach to the plastic media. The feed water source is the effluent from column 5.
Column 4: 5/8" plastic pall rings form the packing for this column. The column packing is seeded biologically as in column 3. The feed water source for column 4 is the effluent from column 2.
Column 5: Cyanide contaminated ore is packed and treated as in column number 2. No biological seed is added. The effluent from this column becomes the feed to column 3.
Flow to column 5 was initiated on day 1. Raw feed water was full strength wastewater from an operational heap leach pad. Wastewater was fed at full strength for 14 days.
At day 14 in the 45 day test, the raw feed water was diluted 12:1 with a water of similar matrix without cyanide and with much reduced heavy metalsconcentrations. This make-up water dilution step represents the use of treated water to further flush the heap leach pad.
The effluent from column 5, (the influent for column 3), had pH adjustment from 9.3 to 8.8. Dilute sulfuric acid was used to lower the pH to determine if treatment performance would improve at slightly reduced pH.
The results are presented in Table 2. Data indicate the performance of column 3 to be superior to other test columns. Column 3 represents drain waters from the heap leach pad with pH adjustment before conventional trickling filter treatment utilizing a mixture of Pseudomonas species acclimated to cyanide. Greater than 96% of total and WAD cyanide species were degraded or removed and 88% of copper present was removed. It is anticipated that under continuous operation on a full scale, biomass wouldincrease and metals removal would also improve.
TABLE 2______________________________________SUMMARY OF TREATMENT PERFORMANCEFOR COLUMNS 1, 3, AND 4Data Represents Average Values Over 45 Day Test Period Influent Effluent Concentration Concentration % mg/L mg/L Removal______________________________________Column 1Prior to DilutionThiocyanate 10.5 8.0 14.0Total Cyanide 130.0 74.5 43.0WAD Cyanide* 124.5 63.3 49.0Copper 6.3 5.8 8.0Ammonia-N 28.6 17.5 39.0After DilutionThiocyanate 4.5 0.8 82.0Total Cyanide 13.9 1.2 91.0WAD Cyanide* 11.8 0.25 98.0Copper 0.8 0.08 90.0Ammonia-N 3.5 3.0 14.0Column 3Prior to DilutionThiocyanate 12.2 1.9 84.0Total Cyanide 64.6 2.4 96.0WAD Cyanide* 58.7 1.9 97.0Copper 5.5 1.8 67.0Ammonia-N 10.0 8.0 20.0After DilutionThiocyanate 5.5 <0.5 91.0Total Cyanide 8.3 0.16 98.0WAD Cyanide* 5.0 0.03 99.0Copper 0.5 0.06 88.0Ammonia-N 8.0 <0.5 94.0Column 4Prior to DilutionThiocyanate 13.0 6.3 51.0Total Cyanide 75.8 5.2 93.0WAD Cyanide* 68.3 4.7 93.0Copper 4.9 1.9 61.0Ammonia-N 16.4 10.3 37.0After DilutionThiocyanate 3.0 1.0 67.0Total Cyanide 12.1 1.2 90.0WAD Cyanide* 10.2 . 0.25 97.0Copper 0.6 0.22 63.0Ammonia-N 6.1 <0.5 92.0______________________________________*WAD Cyanide is analyzed as Weak Acid Dissociable Cyanide, measured according to ASTM standards.
Conversion of ammonia to nitrate was significant. Experience indicates thatstaging of reactors allows nitrifying bacteria to proliferate in the absence of cyanide thereby improving nitrification efficiencies.
Column 4 performed well, however, the slight improvement in treatment efficiency in column 3 is likely related to operation at decreased pH. Column 1 performance indicates that treatment can be implemented by biological seeding of the ore stockpile. A small column is well oxygenatedand may not fully represent a large ore stockpile depleted of oxygen within. It is expected that direct stockpile treatment will be advantageous.
EXPERIMENT 2
Phase 2 of the testing program involved the use of a 2.0 meter Rotating Biological Contactor (RBC).
The 2.0 meter RBC test unit consists of 4 separate compartments each with atotal surface area of about 2000 ft 2 , i.e., a total disk surface area of about 8000 ft 2 . The hydraulic flow rate was set at 1.5 gallons perminute, providing hydraulic loading rate of 0.27 g/day ft 2 .
Before introduction of raw wastewater feed, biomass growth was established on the disk and acclimated to a water source containing 35 mg/L total cyanide and 15.5 mg/L WAD cyanide. The biomass consisted of a mixed culture of species of Pseudomonas acclimated to elevated cyanide concentrations.
Analysis of the heap leach pad drainwaters to be treated is presented in Table 1. Approximately 5400 gallons of this wastewater was transported to and stored at the treatment site. Wastewater to be treated was maintained at 60.5°+/-3.0° F. during the testing period.
The treatment performance test design began with dilution of the wastewaterwith a make-up water similar in chemical composition, but containing only trace concentrations of cyanide and thiocyanate. The total cyanide and cyanate concentrations of the wastewater to be tested were increased to 50% of the total influent flow over the test period. Hydraulic loading rates were maintained at 0.5 to 1.5 g/day/ft 2 . Experience indicates that hydraulic loading rates of 5.0 g/day/ft 2 are achievable. Resultsof the 2.0 M RBC test program are presented in Table 3.
TABLE 3______________________________________SUMMARY OF TREATMENTPERFORMANCE FOR 2.0 M RBC Influent Effluent Concentrations Concentrations % Re- mg/L mg/L moval Min Max Avg Min Max Avg Avg______________________________________Thiocyanate 1.0 29.0 6.5 <0.5 9.0 2.1 68Total 4.61 62.45 15.4 0.10 3.0 1.44 91CyanideWAD 3.43 54.20 12.45 0.02 2.20 0.59 95Cyanide*Copper 0.44 6.46 1.95 0.21 4.37 1.24 37Ammonia 6.18 23.6 13.12 0.74 21.20 9.46 28______________________________________*WAD Cyanide is analyzed as Weak Acid Dissociable Cyanide, measured according to ASTM standards.
The test procedure was designed to optimize removal of cyanides and thiocyanate. Prior testing has determined that ammonia, copper, and other heavy metals can be removed with greater efficiency by adding surface area(media) in a staged filter or additional RBC's.
Removal of total cyanide and WAD cyanide was greater than 95% at peak loading rates. Average removal of total cyanide and WAD cyanide was 91% and 95% respectively. The influent pH was maintained at approximately 9.0 and the effluent pH averaged 8.2. This pH depression is caused by intermediate products of degradation such as SO 3 formed during thiocyanate degradation. Hydraulic loading rates of 1.0-5.0 g/d/ft 2 are proposed for the wastewater tested. A hydraulic retention time of 0.75to 1.0 hours is adequate for treatment.
The foregoing invention has been described by test results from several physical systems to promote a singular process. Mixed cultures of Pseudomonas species acclimated to cyanide are used in the processes. It isobvious that the process has broadened applications subject to modifications to fit specific sites within the scope of the appended claims.
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Biological treatment process removes free and metal complexed cyanides, and thiocyanate through oxidations. Even high concentrations of these pollutants are workable. Toxic heavy metals are absorbed and adsorbed within a biofilm. This process has been adapted to and performs well at high cyanide concentrations (e.g., even above about 100 mg/L and high pH (e.g., even higher than about 9.5). Mixed cultures of adapted strains of Pseudomonas are utilized to perform biological oxidation within the system. End products of oxidation include carbonates, sulfates, and nitrates. The pH is neutralized by metabolism of, or by, intermediate reaction products. The biological processes can be utilized as a pretreatment or post-treatment process in conjunction with chemical processes.
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CROSS-REFERENCE
This application is related to application Ser. No. 08/286,942, filed Aug. 8, 1994, for "Silicon Carbide Carrier For Wafer Processing And Method For Making Same".
FIELD OF THE INVENTION
The invention relates to fixtures or carriers ("boats") used in the manufacture of semiconductor devices such as diodes, transistors and integrated circuits. More particularly, the invention relates to silicon carbide carriers that are used in semiconductor fabrication processes that require the use of high temperatures and/or corrosive fluids. The carriers are particularly suited for use in chemical or thermal processing of semiconductor wafers, in vertically-oriented processing equipment, at ambient or elevated temperatures, in vacuum, gaseous or liquid processing environments.
BACKGROUND OF THE INVENTION
The requirements for cleanliness and the elimination of contaminants in the processing of semiconductor wafers are well documented; see, for example U.S. Pat. Nos. 3,951,541, 3,962,391, 4,093,201, 4,203,940, 4,761,134, 4,978,567, 4,987,016, and Japanese Patent Publication JP 50-90184. To maintain extremely high purity during processing, it is known that such fixtures should be totally free of contaminants, to the extent commercially feasible. It is also known that the carriers should be stable at elevated temperatures, and when subjected to corrosive or oxidizing conditions. Typical corrosive or oxidizing conditions to which the carriers should remain inert are set forth in U.S. Pat. Nos. 4,987,016 and 4,761,134.
Quartz has been and continues to be the most common material used for these components and fixtures. However, quartz has certain deficiencies, such as structural weakness at high temperatures, susceptibility to etching by commonly used acids, and a coefficient of thermal expansion that differs from that of certain materials which are deposited thereon during normal use.
The prior art discussed below addresses the construction of silicon carbide (SIC) boats which have thus far had the most commercial success--a porous SiC formed by casting. These references disclose the drawbacks of quartz, and the benefits of using SiC. They also disclose the drawbacks of the casting method of producing SiC boats. In order to avoid the deficiencies of porous SiC, prior art methods apply a SiC coating layer by chemical vapor deposition (CVD) over the cast SiC. However, an overcoat of CVD SiC does not completely eliminate the problems with porous SiC, since the coating can crack or chip, and thereby expose the porous SiC. Thus, a carrier that consists entirely of CVD SiC is preferred, thus avoiding the problems of porous SiC.
A number of attempts have been made to improve on quartz. The most suc- cessful is a porous silicon carbide infiltrated with silicon, disclosed in U.S. Pat. No. 3,951,587. The problem with such a carrier is that the silicon can etch out when exposed to commonly used cleaning solutions, e.g., strong acids, such as nitric acid, illustrated in U.S. Pat. No. 4,761,134. Other workers (see U.S. Pat. No. 4,761,134) propose to solve this problem by applying an impervious coating, generally a chemical vapor deposited silicon carbide (CVD SiC) coating on the surface of the silicon-filled silicon carbide, or on a porous silicon carbide that has not been filled with silicon (see U.S. Pat. No. 4,987,016). The drawback to these approaches is that any chip, break or crack in the coating will expose the undesirable substrate. U.S. Pat. No. 4,761,134 discusses this drawback as it pertains to CVD SiC applied on an untilled porous SiC substrate. However, the discussion neglects to point out that a similar weakness is inherent in the approach disclosed and claimed in this reference. U.S. Pat. No. 5,283,089 discloses depositing silicon carbide or silicon nitride onto a silicon carbide or silicon nitride matrix to form wafer boats and other components for semiconductor diffusion furnaces.
The preferred approach is to fabricate the carrier entirely from CVD SiC. In this approach, there is no possibility of a silicon-filled or porous substrate being exposed. The CVD SiC fixture also has the advantage of being cleaner than the cast and sintered, or reaction-bonded SiC carriers disclosed in the previously cited references.
The following references describe carriers that are composed entirely of SiC. U.S. Pat. No. 4,978,567 describes a CVD SiC fixture for processing a single wafer at a time, in a furnace designed to do single wafer processing. There is a clear need for a boat for batch processing, capable of holding from 25 to 50 or more wafers. The carrier described and claimed in U.S. Pat. No. 4,978,567 cannot be used for batch processing.
Japanese Patent Application No. JP 50-90184 describes a hollow beam made of CVD SiC to hold wafers. However, this device requires that three or four such beams be joined together by a means of support at the ends. While the boat described in JP 50-90184 fulfills the need for a boat that can hold a plurality of wafers during semiconductor processing, the boat is fragile and relatively complex, and hence costly to manufacture. There is a need for a carrier that uses a single piece of SiC to achieve the same result, and thus is stronger and more economical.
Japanese Patent Application No. Sho 55-82427 discloses a boat consisting of a single piece of silicon carbide, formed by CVD on a graphite substrate. However, the the boat has a rectangular cross-section, which is undesirable because it requires an inefficient use of furnace space. Moreover, the rectangular design causes the mass of the boat to be unnecessarily large, which adds excess thermal inertia, and distorts the thermal pattern developed in the wafers during processing. In diffusion processes, for example, the excess thermal mass of a boat can cause temperature variations across the wafer area, and thereby alter diffusion patterns. Such variations cannot be offset by changes in process parameters. Still further, excess wafer area is covered by the slot walls or the connecting end members. In addition, the design includes partially enclosed areas that will distort gas flow patterns, and will increase the time required to exaust gases contained in such partially enclosed areas.
JP 55-82427 also fails to reveal the size of the boat, relative to the size of the wafers to be carried. If the height of the boat is small relative to the wafers, the slots will not provide adequate horizontal support to maintain the wafers in a vertical position. If the height of the boat is large relative to the diameter of the wafers, adequate horizontal support will be provided, but the walls of the slots will then cover an excessive area of each wafer.
U.S. Pat. Nos. 3,962,391, 4,093,201 and 4,203,940 (all assigned to Siemens) describe methods for making carriers which hold a number of wafers and are produced by depositing CVD silicon or CVD silicon carbide on a generally cylindrical graphite form. However, these patents describe carriers that are not suitable for the most widely used wafer processes. The devices described in U.S. Pat. Nos. 3,962,391 and 4,093,201 do not have means for holding the wafers apart, with a uniform gap between each of the wafers which is required in most batch semiconductor processes. U.S. Pat. No. 4,203,940 describes a carrier design that requires the grinding of slots in a silicon or silicon carbide form to provide means for holding the wafers apart with a gap between each pair of wafers. However, the design described in the latter patent allows only two narrow slots to hold each wafer.
Since two slots do not provide adequate wafer support, the industry has developed carriers having three or four vertical support points to hold each wafer. This is beneficial in the processing of silicon wafers, since it allows the wafers to be held in a more uniform and more parallel position, while minimizing the wafer area covered by the support points. Minimizing the wafer area covered by the support points of the holder maximizes the area of the wafer available for productive use. The general guidelines for the design of these widely used wafer carriers is described in the SEMI International Standards, published by Semiconductor Equipment and Materials International, Mountain View, Calif. The information contained in these standards is incorporated herein by reference.
The above patents are directed primarily to the problems connected with boats to be used in horizontal furnaces, wherein the wafers are supported in a vertical position. Instead, the present invention is directed to boats to be used in vertical furnaces, wherein the wafers are supported in a horizontal position. There is no known example of a boat that works well for use in both vertical and horizontal furnaces.
SUMMARY OF THE INVENTION
The present invention provides a CVD SiC wafer boat for use in vertically oriented furnaces for the manufacture of semiconductor devices, including features that eliminate the disadvantages of the above-described structures, and having the added advantage of conforming with the dimensional requirements for standard furnace systems.
The preferred carrier of the present invention consists of a single piece of nonporous SiC having a uniform bulk density in excess of 3.18 grams per cubic centimeter (99% of maximum theoretical density), and a purity of at least 99.99%. It is configured as a generally cylindrical shell section, portions of which extend outwardly beyond the radius of the wafers to be held, while at least two separated portions have a more limited outward extension, just within the radius of the wafers to be held. These latter portions include a plurality of orthogonal slots or grooves, to provide the necessary wafer separation and support. Since the carrier is to be used in a vertical position, the wafers are supported in a horizontal position, parallel to each other.
In a preferred embodiment, the carrier walls have a substantially uniform thickness, except for the areas where the wafer slots are located. The slot areas of the carrier wall are preferably about one-half to three-fourths as thick as the remaining walls. This feature minimizes thermal interaction between the wafers and the carrier; and also reduces the amount of wafer back-surface covered by the slot walls.
The carrier portions that include wafer slots need not be inwardly convex, nor is it necessary for such portions to have a single curvature. For example, such portions may be shaped to include fiat and/or slightly concave central segments, such that the slots provided therein have a uniformly shallow depth, whereby only a minimum area of the wafer edges are covered, after insertion into the slots. In such a configuration the lower side of each slot provides vertical support for the wafer, and also provides alignment, to ensure a uniform parallel separation between adjacent wafers. In combination, the slots must be positioned to support each wafer at locations distributed along more than 180 degrees of wafer perimeter.
Both ends of the cylindrical section can be left open to form an open-ended carrier. Or, the ends can be closed to form a closed-end carrier. Open areas may be formed in the bottom or in the sides of the carrier, for gas circulation, or the draining of fluids used in cleaning or wet processing, or to reduce the mass of the carrier.
Another aspect of the invention is embodied in a process for making the carrier, which begins with the step of shaping the exterior of a substrate or mold, to provide the exact geometry required for the inside surface of the carrier. A graphite mold, for example, is shaped into the form of a cylindrical section, and is machined to provide at least two spaced-apart segments having a radius slightly less than the radius of wafers to be processed, while the remainder of the useful surface is provided with a radius slightly greater than the radius of the wafers to be processed. The mold is masked in areas where no deposition is desired.
Next, silicon carbide is formed on the mold surface, by chemical vapor deposition; and the resulting CVD shell is separated from the mold. Orthogonal slots or grooves are then machined into the reduced-radius portions, to provide wafer support locations. Other features of the boat may also be shaped by grinding, such as the length and height. Separation of the mold is usually achieved by destructively burning away the graphite, whereby only the deposited shell remains. Such grinding of the SiC may be performed before or after removing the mold, or a combination of before and after.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of one embodiment of the present invention.
FIG. 2 is a cross-sectional view of the embodiment of FIG. 1.
FIG. 3 is a side view of another embodiment of the invention.
FIG. 4 is a cross sectional view of the embodiment of FIG. 3.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIGS. 1 and 2, boat 20 is seen to comprise cylindrical shell section 22 of chemical vapor deposited SiC, having outwardly convex surface 23, inwardly concave surface 24, and fiat surfaces 25. A portion of each of surfaces 25 lies inside the radius of wafer 26, and these surfaces include wafer slots 27 and 28, respectively. Surfaces 23 and 24 lie outside the radius of wafer 27 to be supported. The slotted portions of cylindrical section 22 subtend an arc, i.e. angle α, of about 181 degrees to 330 degrees. The specific geometry of those portions of the boat lying outside the wafer radius may take many forms, but generally have a curved surface with a single radius, except for a transition segment between those portions lying inside and outside the wafer radius, respectively. Windows may be provided in surfaces 23 and 24, for example, to permit the flow of process gases as well as to decrease the weight of boat 20 by removing unnecessary mass.
Boat 20 has two slot-containing fiat surfaces 29 and 30 which extend partly within the wafer radius, and partly outside the wafer radius. Surfaces 29 and 30 are provided with a plurality of coplanar grooves or slots 31 and 32, respectively, into which the wafers are placed. The outermost extensions of slots 31 and 32 may lie slightly within the wafer radius, or slightly beyond the wafer radius.
The length, L, of slots 27 and 28 is calculated by determining the angle, θ, subtended by the slots. In the carriers of this invention, θ ranges from approximately 5° to approximately 50°.
FIG. 2 shows that the cross section of boat 20 includes three shell portions that lie outside the wafer radius, and four portions that lie inside the wafer radius. Coplanar slots 27, 28, 31 and 32 for supporting wafer 26 are provided in the portions that lie inside the wafer radius. The cross section must be configured so that the slots provide wafer support distributed over at least about 181 degrees of the perimeter of the wafer, so that gravity is not allowed to tilt or pivot the wafer, with respect to its diameter, or with respect to any other axis lying in the plane of the wafer. Of course, the amount of tilt would be small, because of the narrow width of each slot; but no tilt whatsoever should be allowed, because even a small departure from an exactly parallel relationship to the next adjacent wafer will severely affect the uniformity of the resulting deposition or diffusion.
FIGS. 3 and 4 illustrate a side view and a cross-section, respectively, of boat 40, including surfaces 41 through 47. Slots 48 in surface 41 are equally spaced along the length of the cylindrical shell. Note that each wafer extends through a slot and beyond the wall of boat 40.
In FIG. 4, boat 40 is seen to include three surfaces 41, 42 and 43, within the diameter of wafer 49, and four surfaces (44 through 47) outside the radius of wafer 49. Each of surfaces 41, 42 and 43 has a row of slots equally spaced along the length of the cylindrical shell. Note that vertical support for each wafer, and precise alignment, is provided only by the lower side of each slot or groove. In addition, the boat includes segments 44 and 45 that extend outwardly well beyond the radius of the wafers.
The thickness of the CVD SiC, "t", should be minimized to reduce the thermal effects on the wafer, yet be thick enough to provide sufficient strength. In the preferred embodiment, this thickness may be in the range of about 0.020 inch to about 0.15 inch or higher. Further t may vary over the body of the boat, due to the nature of the CVD process and/or the requirements of the semiconductor manufacturing process. For instance, it is advantageous to have a thinner CVD SiC thickness at the support points to reduce the thermal effect of the boat on the wafers.
While the previously cited references generally refer to high temperature processing of semiconductor devices, the present invention includes the use of the CVD SiC component in operations that are performed at lower temperatures, including room temperature or below. Many cleaning or etching processes take place at these lower temperatures in corrosive or oxidative liquids or gases. In addition to, or in place of, elevated temperatures, these processes may use ultrasonic, plasma or other processing techniques to produce the desired effect on the wafers. CVD SiC wafer boats of the present invention are more stable in these corrosive environments.
PROCESS FOR MAKING CVD SiC BOAT
In the process of making one or more carriers of the present invention, one or preferably multiple layers of SiC are deposited onto a cylindrical form or mold. The desired geometric shape of the boat is machined into the form, which is preferably graphite or other suitable substrate material for coating with CVD SiC. In the preferred embodiment, the graphite is purified using a high temperature chlorine process or other suitable purification process to minimize the content of elements other carbon.
The geometric shape of the boat is then machined into the cylindrical form. A mask is placed over the backside of the form to prevent the deposition of SiC. Similarly, the ends of the form can also be masked to prevent closing the ends when an opened end boat is being made. Alternatively, these areas may be left unmasked, and the subsequently coated surfaces can be ground or cut away to expose the graphite form.
The form is placed in a furnace suitable for applying a CVD SiC coating and a layer of CVD SiC is applied to the form using a chemical vapor deposition process. Suitable processes for applying the CVD SiC coating are well known in the industry. The process generally involves heating the form to a suitable temperature, introducing a gas or combination of gases which contain silicon and carbon atoms, the gases being at, above or below atmospheric pressure and allowing the gases to react to form a silicon carbide layer on the form. The SiC layer may be deposited in single or multiple steps to achieve the desired thickness of silicon carbide. Examples of the suitable processes are described in the previously cited U.S. Pat. Nos. 3,962,391; 4,093,201; 4,203,940; and 4,978,567 and Japanese Patent Publication JP 50-90184.
The masks, if used, are removed to expose the underlying form or, if masks are not used, the CVD SiC coating is cut or ground away from the back and/or ends of the form. The graphite form is then removed intact, or removed by grinding, machining, burning, grit blasting, chemically dissolving or oxidizing, or other suitable method or combination of these methods.
The resulting CVD SiC form is ground, using diamond grinding wheels and/or other commercially available methods of shaping ceramics, to form the slots, to reduce the form to the desired length and width, and to form the base and/or other features of the boat. In some instances it may be advantageous to perform some or all of the grinding prior to removal of the graphite form from the CVD SiC.
In some designs, it may be advantageous to grind holes completely through the CVD SiC, for instance, to provide open areas for gas circulation, for insertion of lifting devices to transport the boats, for the draining of fluids used in cleaning or wet processing, or for other reasons.
The method of the invention produces a boat having essentially the desired final shape, upon completion of the deposition step. Thus, subsequent grinding is required for only 25% or less of the inner and outer surface areas. An especially unique feature of the process is the selective formation of relatively thinner walls in the areas of the carrier where slots are provided to support the wafers.
EXAMPLE
A mold is prepared by machining a hollow graphite cylinder, to shape its outer surface in the exact configuration required for the inner surfaces of the wafer carrier. Since the carrier is designed to hold wafers having a radius of 2.46", the graphite mold is selected to have a slightly larger outer radius of 2.72".
The graphite cylinder is purified at 2,000 degrees C. with chlorine gas in a purification reactor. The ends of the cylinder are then masked to prevent the coating gases from entering the interior of the cylinder. The masked cylinder is then placed in a CVD reactor and silicon carbide is deposited on the exposed surfaces by the pyrolysis of methyltrichlorosilane. The CVD reactor is designed to rotate the parts to promote uniform coating. The deposition is completed in two separate runs, and the cylinder inverted after the first run. The masks are removed from the ends of the cylinder.
The cylinder is ground, using diamond tools, to the desired length of 7.0 inches, and is then ground longitudinally to remove the front portion of the cylinder. The graphite is removed by combustion in air at 1600 degrees F. The wafer slots are ground into the carrier. The slots were 0.2" deep, 0.20" wide and on 0.3" centers. The exposed corners of the carrier are then chamfered using a diamond grinding wheel.
Without departing from the spirit and scope of this invention, one of ordinary skill in the art can make many other changes and modifications to the wafer carrier of the present invention to adapt it to specific usages and conditions. As such, these changes and modifications are properly, equitably, and intended to be, within the full range of equivalents of the following claims.
For example, the invention includes boats that have five, six, or more separate surfaces with slots or grooves therein for supporting wafers. Also, the invention includes boats having slots distributed over more than 180 degrees of the wafer circumference, even though the boat itself does not have a perimeter that subtends an arc of more than 180 degrees, with respect to the central axis of the boat. This is readily apparent for an embodiment wherein the slot configuration allows the wafers to be inserted deep enough into the boat, so that the center of each wafer is located between the rear of the boat and the central axis of the boat.
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A single piece, high purity, full density semiconductor wafer holding fixture for holding a multiplicity of wafers and consisting essentially of chemical vapor deposited silicon carbide (CVD SiC). The wafer carrier is advantageous for the fabrication of electronic integrated circuits in a vertical furnace, where high temperatures and/or corrosive chemicals are present, where dimensional stability of the holder is advantageous to the process, and where introduction of contaminating elements is deleterious to the process. The method for making such an article comprises shaping a substrate, e.g. graphite, which on one surface has the form of the desired shape, said form comprising raised longitudinal sections to support the silicon wafers at the edges of the wafers, chemically vapor depositing a layer of silicon carbide onto the substrate, removing the substrate intact or by burning, machining, grinding, gritblasting and/or dissolving, and grinding the silicon carbide in any areas where a more precise dimension is required.
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This invention relates to a wall element for use in constructing walls, and a wall system constructed of two parallel rows of a plurality of the wall elements laid in courses in interconnecting relationship, the wall system being used as construction forms for retaining fluid concrete, or other materials such as sand, paper, insulation, or other filler materials, poured into the space therebetween, whereby the two walls remain as a permanent part of the completed wall system, and a method of constructing the described wall system from the wall elements and accessory parts.
BACKGROUND OF THE INVENTION
In concrete forming, to construct walls and the like, it is common practice, to construct a temporary form from lumber, or other materials, to provide a retaining space into which concrete alone, or in combination with other materials, is poured in its fluid condition, after which the concrete is allowed to set. After the concrete has set to a predetermined solid form capable of supporting itself, the form is stripped away. Sometimes, the surfaces of the concrete are cleaned and patched to give a smooth surface if that is required by the job specifications. The forming material is hauled away, perhaps to be discarded, or to be used on another job site, if the forming material can be so adapted.
Because of the considerable hydrostatic pressure that is created by the concrete when it is poured to any reasonable depth, considerable lumber, or other materials, and sturdy construction of the forms are required to provide the necessary strength to retain the heavy concrete. Considerable time and hence expense is required by carpenters or other assembly men to construct the forms which in the end serve only a temporary purpose, namely, retention of the poured-in-place concrete until it has set to a strength strong enough to support itself.
The result of this conventional method of forming concrete walls and the like usually gives an uneven surface showing the imprint of the form itself. Further, the concrete often is not tamped into all areas of the form sufficiently, thereby causing depressions, gaps or other imperfections in the poured-in-place concrete. These imperfections must subsequently be repaired by a cement patching technique which involves extra time and expense. Further, when the concrete forming technique described is used, decorative finishes to the concrete surface cannot be provided without further work and procedure.
The applicant is the owner of two Canadian patents, Canadian Pat. Nos. 922,495, granted Mar. 13, 1973, and Canadian Pat. No. 941,588, granted Feb. 12, 1974, both naming John Rudichuk as inventor. These two patents disclose and claim a wall forming system that comprises a series of wall elements that are laid in superimposed courses in two parallel rows, to provide a pour space therebetween. The two parallel rows of elements are held in place by a system of H-hooks. When the parallel walls have been erected with the H-hooks in place, the fluid concrete is poured in the pour space between the parallel walls and is permitted to set. The concrete sets with the wall elements and H-hooks in place to provide a unitary wall system.
In the Rudichuk wall system, the wall elements must be constructed to close tolerances with holes therein for receiving the legs of the H-hooks. The H-hooks must also be constructed to close tolerances so that they will fit in the holes in the wall elements. The holes in the wall elements and the close tolerances required increase the basic production cost of the wall elements and the H-hooks. The protruding legs of the H-hooks also slow erection time because the holes in the wall elements must be carefully fitted over the legs, a time consuming procedure. Furthermore, the wall elements are flat on the top, bottom and end surfaces and hence when they are placed in abutting relationship with each other, there is no barrier to the passing of moisture between the respective wall elements.
To provide further background for the invention, the following is a list of United States and British patents that disclose and claim various systems for forming walls using wall elements and various tying systems:
______________________________________U.S. Pat. No. Inventor______________________________________2,029,082 Odam2,181,698 Langenberg et al.2,372,038 Westveer3,238,684 Wood3,562,991 Custusch______________________________________British Patent No. Inventor______________________________________266,956 Bemis______________________________________
SUMMARY OF THE INVENTION
The present invention overcomes many of the disadvantages of the prior systems in the art by utilizing an outer form made up of two parallel rows of a plurality of wall elements held in fixed relation by horizontally disposed H-hooks, between which fluid concrete or other filling material such as sand, paper, insulation, or the like, is poured. The finished wall is comprised of the poured-in-place concrete, or other filling material, the H-hooks and the plurality of wall elements, the latter of which remain as part of the overall wall structure and make up the outwardly visible surface of the structure. The poured concrete or other filling material is concealed. The wall elements and the concrete or filling material poured therebetween, by being secured together by the system of H-shaped cross ties provides a wall structure that is held in place in somewhat the same manner as are concrete walls held together by steel reinforcing rods.
To add strength to the overall wall, a suitable adhesive material may be applied between the wall elements to cement them together. The adhesive material can also serve as a vapour barrier to prevent or inhibit the passage of water vapour between the wall elements.
The danger well known in the concrete construction art of having the wall collapse by the removal of forms before the concrete reaches its self-supporting strength is eliminated since the combination of wall elements and H-cross ties form part of the wall structure and thereby provide a basically self-supporting wall. A saving in time, labour and material costs may be realized over conventional concrete construction techniques because construction and subsequent removal and disposal of conventional forms is not required. The wall is complete once the concrete or other filling material has been poured into the cavity between the parallel rows of wall elements and adhesive material applied in the joints, if adhesive is being used.
With the precast members, subflooring construction can commence immediately after pouring, thus saving time. With the present invention, much of the conventional bracing and supports is not required, and also conventional excavation required to accommodate such supports is not required because the form is essentially self-supporting. In addition, because exterior supporting form work is not usually required, it is possible to erect a wall according to the subject invention very close to adjoining structures, or objects. Erection of the subject invention can also take place relatively quietly, and this is an advantage in areas where the usual construction noise cannot be tolerated or is prohibited.
The width of the concrete pour space between the form walls can be varied by using H-cross ties of varying cross bar size to suit the nature of the wall construction required. The size and configuration of the retaining wall elements themselves can be varied by selecting appropriate types and quantities of wall elements. The individual wall elements may be cast with assorted surfaces such that the completed wall provides a decorative block appearance, or a flat, uniform surface.
There are several main advantages of the subject invention over prior wall constructions known to the applicant. These advantages are discussed as follows:
(1) The basic wall elements, unlike most other wall building blocks taught in the art, have no holes, openings, or wells therein. The basic wall elements are of relatively simple construction, and this uncomplicated design lends itself to low cost and easy, reliable production of the basic wall elements. A static mold can be used to form the wall elements, and no moving parts are required in order to form holes, or other openings, in the wall element.
(2) The tongue and groove design of the basic wall element, particularly when the tongue and grooves extend on all four end surfaces of the wall element, provide upon interlocking with one another a natural moisture transmission barrier, a feature which is not present when the ends of the building blocks are formed with flat abutting edges. Moisture penetration into walls of buildings, and the like, can frequently be a troublesome problem, because moisture tends to promote deterioration and degradation of the wall system. To improve the water barrier properties or strength of the wall, adhesive can optionally be used in the tongue and groove joints.
(3) In the wall systems disclosed in Canadian Pat. Nos. 922,495, and 941,588, both naming John Rudichuk as inventor, an average of four H-ties per building block are required. In the present invention, only an average of two H-shaped cross-ties are required per wall element. A basic H-shaped cross-tie is a relatively expensive item and cutting in half the substantial number of H-shaped cross-ties that must be used in erecting the wall, can result in a considerable construction cost saving.
(4) The subject invention enables a wall to be erected in a very simple manner. The horizontally disposed H-cross tie design lends itself to simplicity in erecting the wall because there are no holes, openings or wells in which ties must be fitted, and no vertically extending legs of vertically disposed H-shaped cross-ties, over which holes or openings in the wall element in the next course of wall elements must be fitted. The elimination of any complex fitting step for each wall element increases the rate at which the wall can be erected. Moreover, while a wall can be erected to precise dimensions, tolerances within the components of the subject invention are less strict than with other wall construction techniques. This factor also promotes accelerated wall erection time.
(5) The rounded groove and the co-operating rounded tongue of the basic wall element permit the wall elements according to the subject invention to be slid easily into place over the matching tongue or groove of the wall blocks in a lower course in the wall. Furthermore, the rounded shape of the tongue and the groove tends to reduce chipping damage to the basic wall element and hence reduce the number of wall elements that must be discarded in erecting any particular wall. The matching tongue and groove design of the subject wall elements also tends to increase the lateral stability of the wall, thereby reducing the necessity to rely upon the H-shaped cross-ties for lateral stability. Further stability can be obtained by applying adhesive between the tongue and groove on adjoining wall elements.
(6) The protruding tongue construction of the basic wall elements provides a ridge behind which the leg of the H-cross-tie fits, thus providing improved holding characteristics for the wall element H-cross-tie combination over a simple groove in the surface of the element in which the leg of the H-cross-tie rests.
The invention in one embodiment is directed to a wall element for use in association with other similar wall elements in the construction of a wall, the wall element having a top, a bottom, two side and two end surfaces, and at least one longitudinal groove in the top or bottom surface thereof, and a matching longitudinal ridge in the opposite top or bottom surface thereof, second and third horizontal longitudinally extending grooves on at least the top surface of the wall element both being parallel to the first longitudinal groove, the second and third grooves being located in the region of the respective ends of the top surface of the wall element.
In the wall element described above, the wall element may be of generally rectangular shape on each of its broad opposing side surfaces, and the top, bottom and two end surfaces of the wall element may be relatively thin in thickness in comparison with the width and length of the two broad side surfaces.
In the wall element described, the second and third grooves on the top surfaces of the wall element may be adapted to receive at least a portion of the legs of two separate H-shaped cross-ties. The wall element may be constructed of concrete.
In the wall element described, the first longitudinal groove and the first longitudinal ridge may be of rounded shape when viewed in cross-section, and the radius of the rounded ridge and the radius of the rounded groove may be approximately the same.
The invention in another embodiment is directed to a wall constructed by utilizing a plurality of the wall elements as described above, wherein the wall elements may be laid in series end to end in at least two superimposed courses in two parallel opposing rows, each of the two parallel courses being of generally the same height and each wall element in each course having an opposite member directly across in the opposing row, the top and bottom surfaces of each wall element overlying or underlying and abutting members in the courses of wall elements above and below, the wall elements being secured together by horizontally disposed H-shaped cross-ties, one lower extension of the H-shaped cross-tie fitting into one of the second or third horizontal grooves on the top surface of one of the wall elements in one row, the other lower extension of the H-shaped cross-tie fitting into one of the second or third horizontal grooves on the top surface of the corresponding wall element in the opposite row, the cross-bar of the H-shaped cross-tie extending between the two opposing elements, one upper extension of the H-shaped cross-tie corresponding to the first lower extension fitting into one of the second or third horizontal grooves on the top surface of one of the wall elements in the same course abutting the first wall element in end-to-end relation, the other upper extension of the H-shaped cross-tie corresponding to the other lower extension fitting into one of the second or third horizontal grooves on the top surface of one of the wall elements in the same course abutting the wall element in end-to-end relation, in the opposite row of wall elements, the cross-bar of the H-shaped cross-tie extending between the two opposing wall elements and linking the two opposing wall elements together.
In a wall constructed by utilizing a plurality of wall elements as described above, the wall elements may be laid in series in a linear direction end to end in two parallel rows on a footing, and may be linked together by horizontal H-shaped cross-ties.
In a wall constructed by utilizing a plurality of wall elements as described above, the wall elements may also be laid in series in a linear direction end to end in two parallel rows on a footing, and the bases of the plurality of wall elements extending in two parallel rows rest in two parallel longitudinal grooves that are formed in the top surface of the footing.
The invention in another embodiment is also directed to a structure comprised of a permanent form and concrete or other filler material poured into the form, wherein the form has inner and outer conforming sides and a pour space in between, the inner and outer sides being comprised of a plurality of wall elements arranged in edge-to-edge and end-to-end abutting relationship, the wall elements having horizontal grooves in the top surfaces of the wall elements adapted to receive stabilizing elements in the shape of H-shaped cross-ties, the legs of the H-shaped cross-ties being adapted to engage in the horizontal grooves, the horizontal bar of the H-shaped tie extending between and securing together the inner and outer sides relative to one another.
In the structure described, the side members may be made of precast concrete. In the structure described, the outer faces of the side members may also have architecturally precast textured finishes.
In the structure described, the top and bottom surfaces of the wall elements may have matching tongue and groove designs so that when two wall elements are superimposed in bottom surface upon top surface relationship above one another, the upper wall element meshes with the lower element.
In the structure described, the respective end surfaces of the wall elements may have a matching tongue and groove design so that a first wall element placed in end-to-end abutting relationship with another wall element meshes with the other element.
The invention in another embodiment is also directed to a wall made up of inner and outer walls composed of two series of matching opposed wall elements arranged in superimposed courses in edge-to-edge and end-to-end abutting relationship, thereby providing a pour space between the inner and outer walls for filling with poured concrete or other suitable material, each wall element having on the top and bottom surfaces thereof respective co-operating tongue and grooves which fit with adjoining, abutting wall elements, the tongue and grooves on the top and bottom surfaces of the wall elements extending over the length of the wall elements, the wall elements being planar units being of relatively broad width and length and relatively thin thickness, the wall elements being linked together by horizontally disposed H-shaped cross-ties the legs of which co-operate with horizontal receiving grooves in the top surfaces of the wall elements in order to secure the two series of wall elements in rigid vertical and rigid spaced relationship to define the pour space between the walls, the pour space between the walls being filed with concrete or other suitable material.
In the wall described, each wall element used in constructing the wall may have at least one horizontal groove in the top surface thereof adapted to receive the horizontal leg of an H-shaped cross-tie, and a tongue and a matching groove being formed on at least the respective top and bottom surfaces of the wall element, the matching tongue and groove extending substantially the entire length of the top and bottom surfaces respectively of the wall element.
In the wall described above, the wall element may be of generally rectangular shape, on each of its broad opposing faces, the wall element being relatively thin in thickness in comparison with the width and length of the opposing broad faces, and the tongue and the matching groove on the top and bottom surfaces may respectively extend over the respective end surfaces of the wall element.
Further understanding of the invention may be had by reference to the accompanying drawings which illustrate specific embodiments of the invention.
DRAWINGS
In the drawings:
FIG. 1 represents an end view of a wall element according to one form of the invention.
FIG. 2 represents a top view of one form of the wall element.
FIG. 3 represents a top view of an alternative form of the wall element wherein tongue and grooves are formed on the end faces of the wall element as well as on top and bottom faces of the wall element.
FIG. 4 represents a perspective view of the manner in which two parallel rows of wall elements are linked together by horizontal H-cross ties to form a basic wall unit.
FIG. 5 represents a perspective view of a corner construction comprising two parallel rows of wall elements linked together with horizontal H-cross ties.
FIG. 6 represents a perspective view of a partially formed wall comprising two parallel courses of wall elements arranged in abutting end to end and superimposed relationship linked together by horizontal H-cross ties.
FIG. 7 represents a front view of an H-cross tie.
FIG. 8 represents a perspective view of alternative methods of forming corner constructions with two parallel rows of wall elements linked together with H-cross ties.
FIGS. 9, 10, 11, 12, 13 and 14 illustrate cross-sections of various constructions of footings.
DETAILED DESCRIPTION
Referring to FIG. 1, which represents an end view of a wall element 1, the wall element 1 is formed with a concave bottom groove 2, in the bottom face of the wall element 1, and a complementary convex top ridge or tongue 3, which is rounded so that it has the same general radius as concave bottom groove 2. Thus, top ridge 3 is formed to match and fit with the bottom groove 2 of a similarly constructed wall element 1. In the embodiment of wall element 1 shown in FIG. 1, the two end faces, one in full view and the other in hidden view, and the broad front and back faces, shown in profile, are flat.
Located on the top surface of the wall element 1 is a tie groove 4 which is located adjacent and parallel with top ridge 3. An optional lateral tie groove 5 may also be formed in the top face of wall element 1. The bottom face of wall element 1 adjoining bottom groove 2 is identified as bottom element face 6.
To avoid an unsightly monolithic broad face appearance to a wall erected with a plurality of abutting wall elements 1 in courses, a front face recess 7 is formed at the top front edge of the wall element 1. Thus, when a plurality of wall elements 1 is assembled in abutting end-to-end relationship superimposed upon each other to form courses, front face recess 7 provides a sight-relieving groove at each element intersection that extends the length of the front face of the wall erected from the plurality of wall elements 1.
Turning to FIG. 2, which shows a top view of wall element 1, it can be seen that the top rounded ridge 3 extends the length of the wall element 1. Two tie grooves 4 are positioned at the two respective ends of the top face of the wall element 1. The front face recess 7 also extends the length of the wall element 1. FIG. 2 also illustrates the optional lateral top face mid-groove 9, which can be located midway the length of wall element 1 to accommodate an additional H-cross-tie for extra stability.
With reference to FIG. 3, which illustrates a top view of an alternative embodiment of wall element 1, it can be seen that the wall element 1, in addition to rounded top ridge 3, and front face recess 7, can be constructed to have an end face groove 10 at one end face of the wall element 1, and a rounded end face ridge 11 at the other end of the wall element 1. The radius of curvature of end face groove 10 is substantially the same as rounded end face ridge 11 so that end ridge 11 of one wall element 1 will fit snuggly into the end face groove 10 of an adjoining wall element 1, when a plurality of wall elements 1 are laid in end to end abutting orientation.
FIG. 4 illustrates the manner in which a plurality of wall elements 1 are assembled together in superimposed relationship to form two adjacent parallel walls. In assembling a wall composed of two parallel rows of wall elements, two wall elements 1 are first set in parallel relationship, opposing one another, on a suitable foundation such as a footing, and then two corresponding wall elements 1 are laid on top of the first two parallel wall elements, the bottom grooves 2 of the upper two wall elements 1 fitting upon the respective top ridges 3 of the two underlying base wall elements 1. The opposing pairs of parallel wall elements 1 are held in place opposite one another by means of horizontally disposed H-shaped cross-ties 8, the legs of which fit in the tie grooves 4 formed at the ends of each of the top faces of the pairs of wall elements 1. By repeating the foregoing described assembly procedure, and utilizing additional wall elements 1 and H-cross ties 8, an entire wall system can be constructed, with two opposing parallel outside faces, and a pour space therebetween, which can be filled with poured concrete or some other suitable wall forming material.
FIG. 5 demonstrates the manner in which a corner can be formed from the basic wall element 1, laid in pairs. The 90° corner-type wall element 1 can be specially formed from specially designed molds, or the corner construction can be formed simply by vertically breaking basic wall elements 1 into required lengths in order to construct on site wall corners as required by the job specification. The ends of the respective parallel wall elements 1 are linked together by horizontally disposed H-cross-ties 8.
FIG. 5 also demonstrates how an H-shaped cross-tie 8 can be positioned in horizontal orientation at midpoint grooves 9 on the upper faces of opposing wall elements 1. The provision of H-cross ties 8 at midpoints along the top faces of the opposing wall elements 1 provide the outer wall elements 1 with additional strength to withstand translated hydrostatic pressures that may occur when concrete is poured in the space that exists between the opposing faces of the wall elements 1.
FIG. 6 illustrates in perspective view a partial assembly of a plurality of abutting wall elements 1 arranged in courses to form two parallel walls which run through a 90° corner, the two parallel walls being linked together by a plurality of H-cross ties 8 being set in the respective tie grooves 4 located on the top surfaces of each wall element 1. The wall assembly rests upon a footing 12, which is common construction practice.
A detail of the H-cross tie is shown in FIG. 7. This H-cross tie 8 is always laid horizontally so that the legs of the H-cross-tie are received in the horizontal tie grooves 4 formed in the top surfaces of the wall elements 1. The advantage of having the H-cross tie 8 lie in horizontal position is that no vertical projections exist over which overlying wall elements 1 must be fitted in place, as in the Rudichuk construction disclosed and claimed in Canadian Pat. Nos. 922,495 and 941,588. The absence of vertical projections increases wall erection time and minimizes the chance that such vertical projections will be bent or damaged.
FIG. 8 illustrates alternative corner constructions that can be used in place of the corner constructions illustrated in FIGS. 5 and 6 above. In FIGS. 5 and 6, no horizontally disposed H-cross ties were present at the precise corners. However, as demonstrated in FIG. 8, H-cross ties 8 can be located directly at the corner of the inside wall element so that in effect one H-cross tie 8a continues in a line with one of the interior wall elements 1a while the other H-cross tie 8b continues in a line with wall element 1b.
In a further alternative, H-cross ties 8a and 8b need not be present and a single diagonally oriented H-cross tie 8c can be used. In this system, the legs of H-cross tie 8c must be bent (which can be done on the job site) so that the overall cross-tie 8c takes on an "arrow" shape. This is necessary so that the legs of the H-cross tie 8c will fit in the angled tie grooves 4 of the respective corner wall elements 1.
In the construction of a basic wall made up of a plurality of wall elements 1, it is customary to first pour a concrete footing (See footing 12 in FIG. 6) to serve as a base for the wall. The top surface of the footing may be constructed to accommodate the overlying rows of parallel walls according to well-known construction techniques, for example, forming a pair of parallel grooves in the top surface of the footing so that the bases of the parallel rows of wall elements are received in the grooves. These grooves thereby provide a holding action against lateral pressure exerted on the bases of the plurality of wall elements caused by poured concrete or other filling material.
The two parallel walls are erected by laying a first course of wall elements 1 in end-to-end abutting relationship, and a second course of opposed parallel wall elements 1 directly opposed to the wall elements in the first wall, the two courses of parallel wall elements 1 thereby defining a pour space in between. The two parallel rows of wall elements are secured in place by laying H-cross ties 8 horizontally in each of the tie grooves 4 that are formed on the top surface at the ends of each of the wall elements 1. The cross-bar of the H-cross tie extends from the top of one wall element 1 in perpendicular manner directly across the pour space to the opposite wall element 1. It will be recognized that the inner and outer walls comprised of a plurality of wall elements 1 must be spaced apart a distance that corresponds basically with the length of the cross bar of the H-cross tie 8 so that the legs of each H-cross tie 8 are received in the respective horizontal tie grooves 4 of the wall elements 1. Furthermore, the opposing wall elements 1 in the parallel rows must be placed so that they are directly opposed to one another so that the tie grooves 4 are directly across from each other. This orientation enables the horizontal legs of the H-cross ties 8 to be laid in position in the grooves 4 located at the ends of the top surface of the opposing wall elements 1.
Once the first course of wall elements 1 is in place in the two parallel rows, the second course of inner and outer wall elements 1 is then placed in end-to-end abutting relationship on top of the first course of the two opposing parallel rows wall elements 1. It is customary, as in conventional brick-mortar wall construction, to stagger the position of the wall elements 1 of the second course of wall elements 1 so that the end joints of the second course of wall elements 1 meet at about the midpoint of the wall elements 1 forming the underlying first course of wall elements 1. The bottom grooves 2 of the overlying second course of wall elements 1 fit precisely over the top ridges 3 of the first course of wall elements 1, to provide a snug fit which is capable of withstanding lateral pressure being placed upon the courses of wall elements 1. The tongue and groove arrangement complements the strength provided by the cross-linking H-cross ties 8.
In the manner described, successive courses of wall elements 1, linked together by the tongue and groove construction and the required number of H-cross ties 8, are laid until a wall of desired height is reached. Once the desired height of wall is reached, the pour space formed between the opposing parallel walls can be filled with poured concrete or some other suitable filling material.
In an alternative embodiment of the invention, wall elements 1 which have grooves 10 and ridges 11 on the end faces of the wall elements 1, in addition to the ridges and grooves on the top and bottom surfaces, can be utilized. Such wall elements 1 can be used where it is desired to have the plurality of wall elements 1 mesh by tongue and groove technique not only on the respective top and bottom surfaces of the wall elements 1, but also at the respective ends of the wall elements 1. Wall elements 1 having the end grooves 10 and end ridges 11 are more expensive to construct, but the use of such wall elements 1 may be advisable where a particularly strong wall is required, or it is desired to provide a barrier between the abutting wall elements 1 to minimize the passage of moisture and other matter into the interior space of the opposing parallel rows of wall elements 1.
The wall elements 1 may be formed from pre-cast concrete, and may optionally incorporate embedded wire, or other reinforcing rods, to provide additional strength to the wall elements 1. This may be necessary to provide resistance to fracturing, particularly in applications where a relatively high lateral strength is required, such as in situations where walls of extreme height are being formed, or where the wall elements 1 are relatively thin in width.
FIGS. 9, 10, 11, 12, 13 and 14 illustrate cross-sectional views of various alternative methods whereby the wall element 1, may be positioned in pairs, on footings. These methods are merely exemplary and are not to be considered as exhaustive.
FIG. 9 illustrates the positioning of pairs of wall elements 1 in pairs of grooves 19 in the footing 12.
FIG. 10 illustrates a method whereby the wall elements are held in place by boards 13 which are temporarily nailed to the footing 12 by nails 14, which are removed after the wall has been built.
FIG. 11 illustrates a method whereby a single broad groove 15 is formed in the footing 12.
FIG. 12 illustrates a system of holding the wall elements in place by means of a U-shaped bracket 16 embedded in the footing 12.
FIG. 13 illustrates a construction where the pairs of wall elements 1 are held in place by pins 17 embedded in pairs in the footing 12.
FIG. 14 illustrates a method of holding the wall elements 1 in place by means of a U-shaped bracket 18 positioned on the footing 12.
While particular embodiments of this invention have been described and shown, it will be understood that many modifications may be made to the invention to adapt it to other models and designs without departing from the spirit of the invention, and it is contemplated by the appended claims to cover any such modifications as fall within the true spirit and scope of this invention.
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This invention relates to a wall element for use in constructing walls, and a wall system constructed of two parallel rows of a plurality of the wall elements laid in courses in interconnecting relationship, the wall system being used as construction forms for retaining fluid concrete poured into the space therebetween, whereby the two walls remain as a permanent part of the completed wall system, and a method of constructing the described wall system from the wall elements and accessory parts. The invention includes a wall element for use in association with other similar wall elements in the construction of a wall. The wall element has a top, a bottom, two side and two end surfaces, and at least one longitudinal groove in the top or bottom surface thereof, and a matching longitudinal ridge in the opposite top or bottom surface thereof, and second and third horizontal longitudinally extending grooves on at least the top surface of the wall element, both being parallel to the first longitudinal groove. The second and third grooves are located in the region of the respective ends of the top surface of the wall element.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims benefit of priority under 35 U.S.C. §119(e) from Canadian Patent Application No. 2,818,322, filed May 24, 2013. The contents in the aforementioned application are hereby expressly incorporated by reference in its entirety and for all purposes.
FIELD OF THE INVENTION
The present invention relates to modifications of bitumen and heavy oil upgrading processes to synthesize synthetic crude oil and other valuable hydrocarbon byproducts operations in an efficient manner and produce high quality refined fuel products such as naphtha, gasoline, diesel and jet fuel for commercial application.
BACKGROUND OF THE INVENTION
It is well established that certain forms of hydrocarbons require upgrading in order to either transport them or enhance value for sale. Further, conventional refineries are not suited to processing heavy oil, bitumen etc. and thus the viscosity, density and impurity content, such as heavy metals, sulfur and nitrogen, present in such heavy materials must be altered to permit refining. Upgrading is primarily focussed upon reducing viscosity, sulfur, metals, and asphaltene content in the bitumen.
One of the problems with heavy oil and bitumen upgrading is that the asphaltenes and the heavy fraction must be removed or modified to create value and product yield. Typical upgraders exacerbate the problem by the formation of petcoke or residuum which results in undesirable waste material. This material, since it cannot be easily converted by conventional methods, is commonly removed from the process, reducing the overall yield of valuable hydrocarbon material from the upgrading process.
The Fischer-Tropsch process has found significant utility in hydrocarbon synthesis procedures and fuel synthesis. The process has been used for decades to assist in the formulation of hydrocarbons from several materials such as coal, residuum, petcoke, and biomass. In the last several years, the conversion of alternate energy resources has become of great interest, given the escalating environmental concerns regarding pollution, the decline of world conventional hydrocarbon resources, and the increasing concern over tailings pond management, together with the increasing costs to extract, upgrade and refine the heavy hydrocarbon resources. The major producers in the area of synthetic fuels have expanded the art significantly in this technological area with a number of patented advances and pending applications in the form of publications. Applicant's co-pending U.S. application Ser. No. 13/024,925, teaches a fuel synthesis protocol.
Examples of recent advances that have been made in this area of technology includes the features taught in U.S. Pat. No. 6,958,363, issued to Espinoza, et al., Oct. 25, 2005, Bayle et al., in U.S. Pat. No. 7,214,720, issued May 8, 2007, U.S. Pat. No. 6,696,501, issued Feb. 24, 2004, to Schanke et al.
In respect of other progress that has been made in this field of technology, the art is replete with significant advances in, not only gasification of solid carbon feeds, but also methodology for the preparation of syngas, management of hydrogen and carbon monoxide in a XTL plant, the Fischer-Tropsch reactors management of hydrogen, and the conversion of carbon based feedstock into hydrocarbon liquid transportation fuels, inter alfa. The following is a representative list of other such references. This includes: U.S. Pat. Nos. 7,776,114; 6,765,025; 6,512,018; 6,147,126; 6,133,328; 7,855,235; 7,846,979; 6,147,126; 7,004,985; 6,048,449; 7,208,530; 6,730,285; 6,872,753, as well as United States Patent Application Publication Nos. US2010/0113624; US2004/0181313; US2010/0036181; US2010/0216898; US2008/0021122; US 2008/0115415; and US 2010/0000153.
The Fischer-Tropsch (FT) process has several significant benefits when applied to a bitumen upgrader process, one benefit being that it is able to convert previously generated petcoke and residuum to valuable, high quality synthetic crude oil (SCO) and high quality refined products with notably increased paraffinic content. A further significant benefit is that the raw bitumen yield to refined products is near or greater than 100%, more specifically greater than 130% yield, a 35% to 65% product yield increase relative to certain current upgrader processes. Another benefit is that there is no petcoke and residuum waste product to impact the environment thus improving overall bitumen resource utilization.
A further benefit of the application of the FT process to a bitumen upgrader is that the FT byproducts can be partially and fully blended with the distilled, separated or treated fractions of the bitumen or heavy oil feed stream to formulate and enhance the quality of refinery products such as diesel and jet fuel. The significant overall benefit is the carbon conversion efficiency is greater than 90%, providing significant reduction in facility GHG emissions and 100% conversion of the bitumen or heavy oil resource without the formation of wasteful byproducts.
A further benefit of the application of the FT process to a bitumen upgrader is that a sweet, highly paraffinic and high cetane content synthetic diesel (syndiesel) is produced. More specifically, beneficial byproducts of the FT process such as paraffinic naphtha and FT vapours (such as methane and liquid petroleum gases (LPG)), have particular value within the bitumen upgrader process and upstream unit operations. FT vapours, virtually free from sulfur compounds can be used as upgrader fuel or as feedstock for hydrogen generation to offset the requirement for natural gas. FT naphtha, primarily paraffinic in nature, can also be used in the generation of hydrogen, but further, due to its unique paraffinic nature, it can also be used as an efficient deasphalting solvent not readily available from current upgrader operations.
It has also been well documented that the use of FT paraffinic naphtha as a solvent for an oil sands froth unit improves the operation and efficacy of fine tailings and water removal at a reduced diluent to bitumen (D/B) ratio and relatively low vapour pressure. This has significant advantages in terms of lowering the size and cost of expensive separators and settlers and increasing their separation performance and capacity rating. This results in virtually dry bitumen froth feed (<0.5 basic sediment and water) to the upgrader, while improving impact on the tailings pond.
Having thus generally discussed the appropriateness of the Fischer-Tropsch technique in synthesizing syngas to FT liquids, a discussion of the prior art and particularly the art related to the upgrading and gasifying of heavy hydrocarbon feeds would be useful.
One of the examples in this area of the prior art is the teachings of U.S. Pat. No. 7,407,571 issued Aug. 5, 2008, to Rettger et. al. This reference names Ormat Industries Ltd. as the Assignee and teaches a process for producing sweet synthetic crude oil from a heavy hydrocarbon feed. In the method, the patentees indicate that heavy hydrocarbon is upgraded to produce a distillate feed which includes sour products and high carbon byproducts. The high carbon content byproducts are gasified in a gasifier to produce a syngas and sour byproducts. The process further hydroprocesses the sour products along with hydrogen gas to produce gas and a sweet crude. Hydrogen is recovered in a recovery unit from the synthetic fuel gas. The process also indicates that further hydrogen gas is processed and hydrogen depleted synthetic fuel gas is also produced. Further hydrogen gas is supplied to the hydroprocessing unit and a gasifying step is conducted in the presence of air or oxygen. The gas mixture is scrubbed to produce a sour water and a clean sour gas mixture. The sour gas mixture is subsequently processed to produce a sweet synthetic fuel gas and a hydrogen enriched gas mixture from the synthetic fuel gas using a membrane. The overall process is quite effective, however, it does not take advantage of the conversion of synthesized streams which are useful for introduction into the hydroprocessing unit for production of synthetic crude, the recycling of unique streams for use in the upgrader, nor is there any teaching specifically of the integration of the Fischer-Tropsch process or the recognition of the benefit to the process of using a SMR and/or ATR in the process circuit to maximize SCO yields and reducing dependence on natural gas.
Iqbal et. al. in U.S. Pat. No. 7,381,320 issued Jun. 3, 2008, teaches a process for heavy oil and bitumen upgrading. In overview, the process is capable of upgrading crude oil from a subterranean reservoir. The process involves converting asphaltenes to steam power, fuel gas, or a combination of these for use in producing heavy oil or bitumen from a reservoir. A portion of the heavy oil or bitumen are solvent deasphalted to form an asphaltene fraction and a deasphalted oil, referred to in the art as DAO as a fraction free of asphaltenes and with reduced metals content. The asphaltene fraction from the solvent deasphalting is supplied to the asphaltenes conversion unit and a feed comprising the DAO fraction supplied to a reaction zone of a fluid catalytic cracking (FCC) unit with an FCC catalyst to capture a portion of the metals from the DAO fraction. A hydrocarbon effluent is recovered from this having a reduced metal content. Similar to the process taught in U.S. Pat. No. 7,407,571, this process has utility, however, it limits the conversion of the otherwise wasteful asphaltene to production of solid fuel or pellets or conversion to syngas for fuel, hydrogen or electric power production. There is no teaching specifically integrating the Fischer-Tropsch process.
In U.S. Pat. No. 7,708,877 issued May 4, 2010 to Farshid et. al. there is taught an integrated heavy oil upgrader process and in line hydro finishing process. In the process, a hydroconversion slurry reactor system is taught that permits a catalyst, unconverted oil and converted oil to circulate in a continuous mixture throughout a reactor with no confinement of the mixture. The mixture is partially separated between the reactors to remove only the converted oil while allowing unconverted oil in the slurry catalyst to continue on to the next sequential reactor where a portion of the unconverted oil is converted to a lower boiling point. Additional hydro processing occurs in additional reactors for full conversion of the oil. The so called fully converted oil is subsequently hydrofinished for nearly complete removal of heteroatoms such as sulfur and nitrogen.
This document is primarily concerned with hydroconversion of heavy hydrocarbon, while not being suitable for bitumen upgrading. It also fails to provide any teaching regarding the use of Fischer-Tropsch process, usefulness of recycle streams, hydrogen generation or other valuable and efficient unit operations critical to successful upgrading of raw bitumen.
Calderon et. al. in U.S. Pat. No. 7,413,647 issued Aug. 19, 2008, teach a method and apparatus for upgrading bituminous material. The method involves a series of four distinct components, namely a fractionator, a heavy gas oil catalytic treater, a catalyst regenerator/gasifier and a gas clean up assembly. The patent indicates that in practicing the method, the bitumen in liquid form is fed to the fractionator for primary separation of fractions with the bulk of the bitumen leaving the bottom of the fractionator in the form of a heavy gas oil which is subsequently pumped to the catalytic treater and sprayed on a hot catalyst to crack the heavy gas oil, thus releasing hydrocarbons in the form of hydrogen rich volatile matter while depositing carbon on the catalyst. The volatile matter from the treater is passed to the fractionator where condensable fractions are separated from noncondensable hydrogen rich gas. The carbon containing catalyst from the treater is recycled to the regenerator/gasifier and the catalyst, after being regenerated is fed hot to the treater.
The method does not incorporate the particularly valuable Fischer-Tropsch process or provide a unit for effecting the Fischer-Tropsch reaction and further, the method is limited by the use of the catalyst which would appear to be quite susceptible to sulfur damage and from this sense there is no real provision for handling the sulfur in the bitumen.
In United States Patent Application, Publication No. US 2009/0200209, published Aug. 13, 2009, Sur)) et. al. teach upgrading bitumen in a paraffinic froth treatment process. The method involves adding a solvent to a bitumen froth emulsion to induce a settling rate of at least a portion of the asphaltenes and mineral solids present in the emulsion and results in the generation of the solvent bitumen-froth mixture. Water droplets are added to the solvent bitumen-froth mixture to increase the rate of settling of the asphaltenes and mineral solids. The focus of the publication is primarily to deal with the froth. There is no significant advance in the upgrading of the bitumen.
A wealth of advantages are derivable from the technology that has been developed and which is described herein. These are realized in a number of ways including:
a) near 100% or greater yield of total refinery products slate from heavy oil or bitumen without the wasteful production of petcoke or residuum; b) high quality synthetic hydrocarbon byproducts such as synthetic naphtha, syndiesel, synjet, synthetic lubes and synthetic wax is produced to highest quality commercial standards; c) maximum utilization of carbon in heavy oil and bitumen to form high quality synthetic hydrocarbon byproducts, with the significant reduction (greater than 50%) in GHG from the facility; d) the distilled and treated streams are substantially void of undesirable chemical and physical properties such as heavy metals, sulfur, Conradson Carbon (CCR) and naphthenic acid (TAN number); e) less natural gas is required to generate hydrogen for upgrading as the FT naphtha, refinery fuel gas, LPG, FT vapours and hydroprocessing vapours can be recycled to generate a hydrogen rich syngas; f) pure hydrogen can be generated from the hydrogen rich syngas using membranes, absorption or pressure swing adsorption units, for use in the hydroprocessing (hydrocracking, isomerisation, hydrotreating) units; g) Fischer-Tropsch (FT) liquids are primarily paraffinic in nature improving the quality and value of refinery product slate; h) FT naphtha is rarely available in any quantity in current upgraders and would be very preferentially used for deasphalting distilled bottoms in a Solvent Deasphalting Unit (SDA) and in a oil sands Froth Treatment Unit; and i) concentrated CO 2 is available from the gasifier (XTL) syngas treatment unit, allowing the upgrader to be a low cost carbon capture ready CO 2 source for carbon capture and sequestration (CCS) projects.
As part of the further advancements that are within the ambit of the technology set forth herein, the refinery aspect is addressed.
In this embodiment of the invention, a process is elucidated to fully upgrade light crude oil typically having an API density of between 22 and 40 and heavy oil with an API density of between 12 to 22 or extra heavy oil or bitumen with a density of less than API 12 API without the production of undesirable hydrocarbon byproduct, such as petcoke, heavy fuel oil or asphalt. The process combines the Fischer Tropsch hydrocarbon synthesis unit with conventional refinery processing steps to produce full commercial specification refined products, such as, but not limited to, naphtha for petrochemicals feedstock, naphtha for gasoline blending, gasoline, diesel, jet fuel, lubricants, wax, inter alfa.
Generally, conventional or simple topping, hydroskimming and light conversion refineries are designed to receive sweet or sour light crude oils >22 API, more specifically 30 to 40 API density for the production of refined fuels. Light refineries are primarily focused on production of gasoline, jet and diesel fuel and if required, the refinery will manage refinery bottoms as asphalt or fuel oil sales. Usually the volume of bottoms is minimal for crude densities greater than 30 API.
In recent years the supply and availability of light crude oil has fallen appreciably and become very costly relative to discounted heavier crude costs. Many conventional refineries have been recently reconfigured to medium conversion refineries to accept further lower cost heavy crude oils (20 to 30 API) resulting in higher fractions of the crude oil converting to residue and being converted to asphalt, sour heavy fuel oil or petcoke. In addition, many refineries have been forced to further upgrade the hydrotreating facilities to produce ultra-low sulfur gasoline (ULSG) and ultra-low sulfur diesel (ULSD) to meet tighter regulatory commercial market specifications. Economics of these modified refineries have become very challenging due to significant capital and processing costs without additional product yield or significant revenue gain.
To further complicate issues, the large volumes of low value world crude oil supplies now take the form of extra heavy crude (12 to 22 API) or bitumen (6 to 11 API) sources from in situ or mining oilsands operations. Complex refinery conversions are now required, involving the addition of deep conversion refinery units such as deep hydrocracking and coking, to accommodate the extra heavy oil and bitumen feeds. These deep conversion refineries, are capital intense and produce significantly lower value byproducts such as petcoke with significant increased emissions of GHG (Green House Gases). Refinery product yields based on extra heavy and bitumen crude oil are about 80 to 90 volume %.
Petcoke has undesirable properties, such as difficult and costly handling, storage and transportation requirements, major environmental impact and contains high levels of sulfur (6+wt %) as well as toxic heavy metals such as nickel and vanadium (1000 ppm+). Therefore petcoke has limited markets and is often a commercial and environmental liability as it is stored or marketed at very low or negative returns.
As the world oil supply transitions more towards the supply of extra heavy oil (12 to 20 API) and bitumen (6 to 12 API), the vacuum bottoms approaches 60 vol % of the whole crude assay. Accordingly, there is a need for an improved process to convert all the heavy oil and bitumen feed to commercial high value product without the production of byproducts such as petcoke and CO2 (GHG), with reduced impact on the environment.
The refinery process to be discussed addresses the needs in this area. Advantages attributable to the process include:
a) Transformation of refiner bottoms, typically >950+F material to synthetic fuels such as FT naphtha, synthetic diesel, synthetic jet fuel, synthetic lube oils, waxes, etc.; b) Elimination of the production of low value hydrocarbon byproducts such as heavy fuel oil, road asphalt and petcoke, resulting in full (100 wt %) utilization of the crude feed regardless of density or blended densities of crude slate; c) Retention and conversion of greater than 90% of all carbon in the feed streams (i.e. crude oil, natural gas, etc) resulting in greater than 50% reduction in CO2 or GHG emissions; and d) Substantial reduction of the Conradson Carbon (CCR), Naphthenic Acid (TAN) and heavy metals and significant amount of sulfur from the main conventional refinery processes. This is advantageous since it permits the use of lower cost, conventional hydroprocessing units (hydrocrackers) with single or multiple fixed bed catalyst systems to upgrade the heavy fractions to high value refinery fuels.
SUMMARY OF THE INVENTION
One object of the present invention is to provide an improved heavy oil and bitumen upgrading methodology for producing refined products and synthesizing hydrocarbons with a substantially increased yield without the production of waste byproducts such as petcoke or residuum.
A further object of one embodiment of the present invention is to provide a process for upgrading heavy oil or bitumen to formulate refined hydrocarbon byproducts, comprising:
(a) providing a feedstock source of heavy oil or bitumen; (b) treating said feedstock to form a distilled fraction and non-distilled bottoms fraction; (c) feeding said bottoms fraction to a syngas generating circuit for formulating a hydrogen lean syngas stream via a partial oxidation reaction and reacting said syngas in a Fischer-Tropsch reactor to synthesize hydrocarbon byproducts; (d) removing at least a portion of fully refined hydrocarbon byproduct for commercial application; and (e) adding an external source of hydrogen to said hydrogen lean syngas to optimize the synthesis of hydrocarbons at least one of which is synthetic hydrocarbon byproduct.
A further object of one embodiment of the present invention is to provide a process for upgrading heavy oil or bitumen to formulate refined hydrocarbon byproducts, comprising:
(a) providing a source of bitumen or heavy oil feedstock and treating said feedstock with distillation to form a distilled and non-distilled bottoms fraction; (b) feeding the non-distilled bottoms fraction to a syngas generating circuit for formulating a hydrogen lean syngas stream via a partial oxidation reaction; (c) treating at least a portion of the said hydrogen lean syngas stream to a water gas shift (WGS) reaction to generate an optimum Fischer-Tropsch syngas; (d) treating said optimum Fischer-Tropsch syngas stream in a Fischer-Tropsch unit to synthesize hydrocarbon byproducts and; (e) removing at least one of upgraded portion of fully refined synthetic hydrocarbon byproducts for commercial application.
The present technology mitigates the oversights exemplified in the prior art references. Despite the fact that the prior art, in the form of patent publications, issued patents, and other academic publications, all recognize the usefulness of a Fischer-Tropsch process, steam methane reforming, autothermal reforming, hydrocarbon upgrading, synthetic oil formulation, stream recycle, and other processes, the prior art when taken individually or when mosaiced is deficient a process that provides the efficient upgrading of bitumen and heavy oil in the absence of residuum and/or petcoke generation.
Synthetic crude oil (SCO) and refined hydrocarbon byproducts, such as naphtha, gasoline, diesel and jet fuel is the output from a bitumen/heavy oil upgrader facility used in connection with bitumen and heavy oil from mineable oilsands and in situ production. It may also refer to shale oil, an output from an oil shale pyrolysis. The properties of the synthetic crude or refined hydrocarbon byproducts depend on the processes used in the upgrading configuration. Typical full upgraded SCO is devoid of sulfur and has an API gravity of around 30 to 40, suitable for conventional refinery feedstock. It is also known as “upgraded crude”. The processes delineated herein are particularly effective for partial upgrading, full upgrading or full refining to gasoline, jet fuel and diesel fuel. Conveniently, the flexibility of the processes allows for fuel synthesis and synthetic crude oil partial upgrading within the same protocol or the partial upgrading as the entire process.
The present invention amalgamates, in a previously unrecognized combination, a series of known unit operations into a much improved synthesis route for a high yield, high quality production of synthetic hydrocarbons. Integration of a Fischer-Tropsch process, and more specifically the integration of a Fischer-Tropsch process with a hydrogen rich syngas generator which uses FT naphtha and/or FT upgrader vapours as primary fuel in combination with natural gas, in a steam methane reformer (SMR) and/or an autothermal reformer (ATR) results in a superior sweet synthetic hydrocarbon byproduct which is synthesizable in the absence of petcoke and residuum.
It was discovered that, by employing a steam methane reformer (SMR) as a hydrogen rich syngas generator using Refinery Fuel, Refinery LPG, FT LPG, FT naphtha and FT/upgrader vapours, in combination with natural gas, significant results can be achieved when blended with the hydrogen lean syngas created by the gasification of non-distilled or treated bitumen or heavy oil bottoms. A significant production increase in middle distillate synthetic hydrocarbons range is realized. The general reaction is as follows;
Natural Gas+FT Naphtha( v )+FT Upgrader Vapours+Steam+Heat→CO+ n H 2 +CO 2 .
As is well known to those skilled in the art, steam methane reforming may be operated at any suitable conditions to promote the conversion of the feedstreams, an example as shown in above equation, to hydrogen H 2 and carbon monoxide CO, or what is referred to as syngas or specifically as hydrogen rich syngas. Significant benefits resulted in greater than 100% increase in middle distillate synthesized hydrocarbon. Steam and natural gas is added to optimize the desired ratio of hydrogen to carbon monoxide to approximate range of 3:1 to 6:1. External CO2 can optionally be added to minimize the formation of undesirable CO2 and maximize the formation of CO in the hydrogen rich syngas. A water gas shift reaction (WGS), pressure swing adsorption (PSA) or membrane unit can also be added to any portion of the SMR syngas circuit to further enrich the hydrogen rich stream and generate a near pure hydrogen stream for hydroprocessing use. Generally natural gas, FT Vapours, Refinery Gas or any other suitable fuel is used to provide the heat energy for the SMR furnace.
The steam reformer may contain any suitable catalyst, an example of one or more catalytically active components such as palladium, platinum, rhodium, iridium, osmium, ruthenium, nickel, chromium, cobalt, cerium, lanthanum, or mixtures thereof. The catalytically active component may be supported on a ceramic pellet or a refractory metal oxide. Other forms will be readily apparent to those skilled.
It was further discovered that employing an autothermal reformer (ATR) as a sole hydrogen rich syngas generator or in combination with the SMR or as a hybrid combination of an ATR/SMR referred to as a XTR, significant benefits resulted in a greater than 200% increase in the FT middle distillate synthetic hydrocarbons. Feedstreams for the ATR or XTR consist of FT naphtha, FT vapours, H 2 rich upgrader vapours, CO 2 , O 2 and natural gas.
Similarly, as is well known to those skilled in the art, autothermal reforming employs carbon dioxide and oxygen, or steam, in a reaction with light hydrocarbon gases like natural gas, FT vapours and upgrader vapours to form syngas. This is an exothermic reaction in view of the oxidation procedure. When the autothermal reformer employs carbon dioxide, the hydrogen to carbon monoxide ratio produced is 1:1 and when the autothermal reformer uses steam, the ratio produced is approximately 2.5:1, or unusually as high as 3.5:1.
The reactions that are incorporated in the autothermal reformer are as follows:
2CH 4 +O 2 +CO 2 →3H 2 +3CO+H 2 O+HEAT.
When steam is employed, the reaction equation is as follows:
4CH 4 +O 2 +2H 2 O+HEAT→10H 2 +4CO.
One of the more significant benefits of using the ATR is realized in the variability of the hydrogen to carbon monoxide ratio. An additional significant benefit of using the ATR is that external CO 2 can be added to reaction to effect a reverse shift reaction to create additional carbon monoxide for enhancement of the FT synthesis unit and reduction of overall facility GHG emissions. In the instant technology, an ATR may also be considered as a hydrogen rich syngas generator, as described previously. It has been found that the addition of the ATR operation to the circuit separately or in combination with the hydrogen rich syngas generation circuit, shown in the example above as a steam methane reformer (SMR), has a significant effect on the hydrocarbon productivity from the overall process. Similarly, a water gas shift reaction (WGS), pressure swing adsorption (PSA) or membrane unit can also be added to any portion of the ATR and combined ATR/SMR or XTR syngas circuit to further enrich the hydrogen rich stream and generate a near pure hydrogen stream for hydroprocessing use.
The present invention further amalgamates, in a previously unrecognized combination, a series of known unit operations to integrate the Fischer-Tropsch process, using a water gas shift reaction for syngas enrichment resulting in a valuable sweet synthetic hydrocarbon byproduct which is synthesizable in the absence of petcoke and residuum.
Accordingly, it is another object of one embodiment of the present invention to provide the process, wherein the water gas shift reactor (WGS) is introduced to at least a protion of the hydrogen lean syngas stream to optimize the hydrogen content for the Fischer-Tropsch process.
Referring now to the drawings as they generally describe the invention, reference will now be made to the accompanying drawings illustrating preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a process flow diagram of methodology known in the prior art for processing of mineable and in situ heavy oil and bitumen;
FIG. 2 is a process flow diagram similar to FIG. 1 , illustrating a further technique known in the art;
FIG. 3 is a process flow diagram illustrating a further variation of the prior art technology;
FIG. 4 is a process flow diagram illustrating a further variation of the prior art technology;
FIG. 5 is a process flow diagram illustrating an embodiment of the present invention;
FIG. 6 is a process flow diagram illustrating a further embodiment of the present invention;
FIG. 7 is a process flow diagram illustrating yet another embodiment of the present invention;
FIG. 8 is a process flow diagram illustrating one embodiment for a low conversion refinery;
FIG. 9 is a process flow diagram illustrating a medium conversion refinery; and
FIG. 10 is a process flow diagram illustrating a deep conversion refinery
Similar numerals employed in the figures denote similar elements.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIG. 1 , shown is a first embodiment of a bitumen production flow diagram based on the prior art. The overall process is denoted by 10 . In the process, the heavy oil or bitumen source 12 may comprise a bitumen reservoir which may be minable or in situ. Generally speaking, the bitumen then may be transported to a heavy oil or bitumen production unit 14 into which diluent or solvent may be introduced via line 16 from a heavy oil or bitumen upgrader 18 . The diluent or solvent can comprise any suitable material well known to those skilled in the art such as suitable liquid alkanes as an example. Once the diluent is introduced via line 16 into the production unit 14 , the result is a mobilizable bitumen blend (dilbit). Once the dilbit or diluted bitumen blend is processed in the upgrader 18 , the so formed synthetic crude, globally denoted by 20 is then treated in a petroleum refinery 22 where subsequently refined products are formulated and with the refined products being globally denoted by 24 .
The production unit 14 primarily removes water and solids from the stream. The diluent or solvent 16 is added to the raw bitumen to provide for the necessary mobilization and separation parameters, primarily providing a reduction in viscosity. In a situation where the bitumen is an oil sand derived bitumen, water is added to the raw material to provide a slurry for transport to the extraction and froth treatment plant and upgrader 18 , as further described in FIG. 2 . Dewatered bitumen is then transported by pipeline (not shown) as a diluent blend or dilbit to the upgrader 18 . The dry raw bitumen is treated to primary and secondary treatment to create a sweet or sour crude oil (SCO). The SCO is transported to the petroleum refinery 22 to be further processed into refined product 24 as indicated above, examples of which include transport fuel such as gasoline, diesel and aviation fuels, lube oils and other feedstocks for petrochemical conversion.
With respect to FIG. 2 , shown is a schematic process flow diagram of oil sands operation for bitumen upgrading. The overall process in this flow diagram is indicated by 30 . Other than the embodiment shown, the system relates to a minable oil sands bitumen production process where raw mined oil sands ore, generally denoted by 32 , from the mine are mixed with water 34 in an ore preparation unit 36 and subsequently hydrotransported to a primary extraction plant, denoted by 38 . In the extraction plant 38 , the greater portion of water 34 and course tailings 40 are separated and returned to a tailings pond 42 .
Partially dewatered bitumen, generally denoted by 44 is transferred to a froth treatment unit 46 . This is where a solvent, typically highly aromatic naphtha (derived from bitumen) or paraffinic solvent (derived from natural gas liquids) is added at 48 to separate the remaining water and refined clays as well as fine tailings. The froth is then treated in a solvent recovery unit 52 where the majority of the solvent is recovered for recycle to the froth treatment unit. The separated fine tailings passes through a tailings solvent recovery unit 50 for final recovery of solvent. The fine tailings are transferred into the tailings pond 42 . The clean dry froth is then introduced into the bitumen upgrader, generally denoted by 54 and illustrated in FIG. 2 in dashed line. Generally speaking the bitumen upgrader 54 incorporates two general processes, a primary and secondary upgrading. The primary upgrader typically consists of two processing methodologies. The first, namely, carbon rejection or coking where the heavy fraction of the bitumen is removed as petcoke. Generally, the synthetic crude oil yield is between about 80 to about 85% by volume and the remaining portion converted primarily by petcoke is returned for storage to the mine. Further the coking process is a severe processing method and leads to higher aromatic content in the synthetic crude oil. The second process, namely hydrogen addition, uses a slurry based catalytic hydroprocessing system with the addition of hydrogen to treat the bitumen blend and produce an unconverted asphaltene reject stream and a synthetic crude oil product. The volume yield of the synthetic crude oil typically is 95% to 103% due to product swelling.
The hydrocarbon product streams from primary upgrading are further treated in secondary upgrader, consisting of hydrotreating units using hydrogen to stabilize synthetic crude products generally indicated as 56 and reduce sulfur and nitrogen impurities. Natural gas is used in a hydrogen unit to generate hydrogen requirements for the upgrader and co-generate electric power for upgrader use. The overall operations in the bitumen upgrader are indicated within the dash lines and these operations are well known to those skilled in the art.
Turning to FIG. 3 , shown is a further partial upgrading process known in the prior art, in this arrangement, the process flow diagram delineates an in situ bitumen production unit. The overall process is denoted by 60 . In such an arrangement, the in situ heavy oil or bitumen is exposed to steam to extract the oil. The raw bitumen 62 is treated in a conventional SAGD or CSS plant 64 to remove water 66 . Diluent 68 is typically added to raw bitumen 62 in plant 64 to create water oil separation and to further provide a diluted blend for pipeline transportation, more commonly referred to in the art as “dilbit” denoted by 70 . The dilbit can be transported over long distances in a pipeline (not shown) to remote refineries where it is blended with conventional crude as a feedstock. More integrated configurations may use distillation, deasphalting or visbreaking, a processing to create a near bottomless sour heavy crude for feed to refineries. This operation creates an asphaltene or vacuum residue stream requiring disposal. This partially upgraded bitumen is suitable for pipeline transportation for heavy oil feed streams greater than 15 API. For heavy oil and bitumen feed streams less than 15 API, some quantity of diluent is still required to meet crude pipeline specifications. The dilbit is processed in a bitumen partial upgrader denoted by 72 with the operations being shown within the dashed line box. The transportable bitumen is denoted by 74 in FIG. 3 . The diluent is often separated at the refinery and returned to the in-situ operation resulting in significant overall inefficiencies. The option to this is external makeup diluent is provided locally at a significant expense.
As will be appreciated by those skilled, the process variations shown in FIGS. 1 through 3 of existing bitumen and heavy oil production facilities either create a waste product such as petcoke or residuum which leads to significant losses or further requires significant quantities of hydrogen or diluent to upgrade the product in order to be suitable as a refinery feedstock. Essentially, the existing processes do not provide a technology capable of capturing the full intrinsic value of the bitumen or heavy oil and has resulted in environmental impact related to disposal and management of undesirable waste products.
Turning to FIG. 4 , shown is a further variation in the prior art of an enhanced bitumen upgrading process. It is the subject matter of Canadian Patent No. 2,439,038 and its United States homolog, U.S. Pat. No. 7,407,571 issued to Rettger, et. al. (Ormat Industries Ltd.).
The overall process is denoted by 80 .
Dilbit or froth 70 is introduced into an atmospheric distillation unit 82 with the non-distilled heavy bottoms being transported and introduced into a solvent deasphalting unit (SDA) 84 and the asphaltene bottoms are then subsequently fed into a gasifier 86 , which gasifier is within the Ormat gasification unit, globally denoted by 88 . The deasphalted material, commonly denoted as DAO is transferred to the hydroprocessing unit 108 for upgrading to synthetic crude oil. As an option, there may be a vacuum distillation unit 110 in the circuit which may introduce captured vacuum gasoils for introduction into hydroprocessing unit 108 . Similarly, the vacuum bottoms are introduced into the SDA 84 to optimize process configuration.
The sour syngas generated by the gasification unit is then passed into a syngas treater 90 for acid gas removal. The acid gas is removed at 92 and treated in sulfur plant 94 producing at least products such as liquid sulfur 96 and CO 2 98 . The treated or “sweet” syngas is then processed in a water gas shift reaction (WGS) process as denoted in the FIG. 4 and referred to as a CO shift reactor 100 . Steam 102 is augmented in the reactor 100 . The water gas shift reaction is merely a shift from the CO to CO 2 to create a hydrogen rich syngas. The hydrogen rich syngas may be then further treated in a typical pressure swing unit (PSA) or a membrane unit where the hydrogen is concentrated to greater than 99 percent. It occurs in unit 104 . The hydrogen generated by 104 , denoted by 106 is then the feedstock for the hydroprocessing unit 108 . Once the hydroprocessing occurs, the result is synthetic crude oil (SCO) denoted by 116 representing about 95 vol % yield and fuel gas denoted by 114 .
Returning briefly to the hydrogen recovery unit 104 , the byproduct of the unit 104 is a tailgas or a low BTU syngas which is used in the SAGD thermal steam generators as fuel to offset the need for natural gas as the primary fuel. The process has merit in that if natural gas is in short supply or there can be significant historic price fluctuation, the enhanced upgrader process is less dependent on the natural gas and can rely on the synthesized fuel for the overall process benefits.
Turning to FIG. 5 , shown as a first embodiment of an enhanced bitumen upgrading circuit process incorporating Fischer-Tropsch technology and hydrogen synthesis. The embodiment of the overall process is denoted by 120 . The overall process is particularly beneficial relative to the processes that were previously proposed in the prior art in that sweet carbon rich syngas is not passed through a water gas shift reaction, as denoted as 100 in FIG. 4 , but rather is supplemented with external hydrogen 138 to create the optimum syngas composition, typically a ratio of hydrogen to carbon monoxide of greater than 1.8:1 to 2.2:1, and preferred as 2 : 1 as feed to Fischer-Tropsch reactor for producing high quality paraffinic Fischer-Tropsch liquids.
It is by the recognition of the usefulness of the Fischer-Tropsch reactor together with the avoidance of waste petcoke/residuum generation and the subsequent hydrogen source addition to maximize conversion of gasified carbon, that draws the proposed interim technology into the realm of being economical, convenient and highly efficient given the yields that are generated for the synthetic crude oil (SCO), greater than 115 vol %, and more specifically greater than 135 vol %.
As is evident, there are a number of unit operations which are common with those in the prior art, namely the atmospheric distillation, vacuum distillation, solvent deasphalting, hydroprocessing, gasification, and syngas treatment.
In the embodiment shown, the Ormat gasification, commonly denoted as unit 88 and discussed with respect to FIG. 4 is replaced with a further sequence of operations (the XTL operations) shown in dashed lines and indicated by 122 . In this embodiment, the gasifier 86 converts the non-distilled bottoms residue with typically oxygen (O 2 ) 124 to generate a hydrogen lean or carbon rich syngas 88 having a hydrogen to carbon dioxide ratio in range of 0.5:1 to 1.5:1, more specifically about 1:1, an example of which is shown in Table 1.
TABLE 1
Typical XTL Gasifier Hydrogen Lean Syngas Compositions
Feedstock Type
Heavy
Vacuum
Syngas Composition (mole %)
Fuel Oil
Residue
Asphaltene
CarbonDioxide (CO 2 )
2.75%
2.30%
5.0%
Carbon Monoxide (CO)
49.52%
52.27%
50.4%
Hydrogen (H 2 )
46.40%
43.80%
42.9%
Methane (CH4)
0.30%
0.30%
0.3%
Nitrogen (+Argon)(N 2 )
0.23%
0.25%
0.4%
Hydrogen Sulfide (H 2 S)
0.78%
1.08%
1.0%
A common byproduct, containing heavy metals and ash, from the gasification is discharged as slag denoted as 126 . The hydrogen lean syngas 88 is then passed into the syngas treatment unit 90 for removal of acid gases 92 to create a sweet hydrogen lean syngas 91 . Additional scrubbing, adsorption and washing technologies (not shown), well known to those skilled in the art, are typically employed to ensure that the sweet syngas is devoid of contaminants such as sulfur compounds which will have significant detrimental impact on the Fischer-Tropsch catalyst. The acid gas is further treated in the sulfur plant 94 to generate elemental sulfur 96 and carbon dioxide (CO 2 ) as was the case with respect to the process of FIG. 4 . The sweet hydrogen lean syngas 91 is then passed into a Fischer-Tropsch unit reactor denoted by 128 . As a possibility, the hydrocarbon by products that are formed subsequently to reaction within the Fischer-Tropsch reactor 128 includes Fischer-Tropsch vapours 184 (CO+H 2 +C1+C2+C3+C4), naphtha 130 , light Fischer-Tropsch liquids 132 (LFTL) and heavy Fischer-Tropsch liquids (HFTL) 134 or commonly know as FT wax.
In order to trim or improve the efficiency of the overall process, the XTL unit 122 and specifically in advance of the syngas treatment unit 90 and/or the Fischer-Tropsch reactor 128 may be augmented with an external supply of hydrogen, indicated by 136 and 138 , respectively. Further, at least some of the vapour from the Fischer-Tropsch reactor may be reintroduced in advance of the syngas treatment unit 90 as indicated by 140 , and/or be used a fuel 114 in the upgrader. The liquids 130 , 132 and 134 are introduced into hydroprocessing unit 108 . This may also be augmented by straight run distillate naphtha 144 may be introduced from atmospheric distillation operation 82 , vacuum gas oil (VGO) 142 from the vacuum distillation operation 110 and optionally, deasphalted oil 112 (DAO) from the SDA unit 84 . A range of hydroprocessing treatments 108 , as an example, hydrocracking, thermal cracking, isomerization, hydrotreating and fractionation, may be applied to the combined streams, individually or in desired combinations, well known to those skilled in the art, to create at least the synthetic crude oil product 116 . As further options, any portion of the Fischer-Tropsch naphtha 130 particularly the paraffinic naphtha indicated by 150 may be reintroduced into the deasphalting unit 84 at 152 or further distributed as the solvent make up 156 for introduction into the oil sands froth treatment unit (not shown but generally noted by 158 ).
Further, additional hydrogen may be introduced into the hydroprocessing unit 108 and hydrotreating unit 160 at 166 and 164 . The hydrogen supply may be taken from the hydrogen supply noted herein previously. From each of the fractionator, hydrotreater 160 , hydroprocessing unit 108 and Fischer-Tropsch unit 128 , product from each of these operations denoted by 170 or 172 , 184 respectively is introduced to fuel gas 114 . Further, a portion of 172 and 170 rich in hydrogen may be combined with the hydrogen lean syngas at 88 or 91 to enrich this stream for optimum performance of the Fischer-Tropsch unit.
Turning to FIG. 6 , shown in the process flow diagram is yet another variation on the methodology of the instant invention. The overall process in this embodiment is denoted by 180 . Similar unit operations from those established in FIGS. 4 and 5 are applicable in FIG. 6 .
The primary changes with respect to FIG. 5 versus FIG. 6 , includes modification of the XTL, unit 122 and incorporation of hydrogen rich syngas generation and recycle of hydrogen rich syngas generated in the Fischer-Tropsch unit 128 .
In greater detail, the XTL, unit 122 is modified to incorporate a hydrogen rich syngas generator, denoted by 182 . The hydrogen rich syngas generator 182 is typically composed of a steam methane reformer (SMR) (not shown) or an auto thermal reformer (ATR) (not shown) and combinations thereof. Natural gas 188 , Fischer-Tropsch vapours 184 , hydrogen rich fuel gas 174 , etc. from the hydroprocessor 108 and fractionation unit 160 and Fischer-Tropsch naphtha 186 may be supplied individually or in combination to unit 122 to generate hydrogen rich syngas 190 where the ratio between the hydrogen and the carbon monoxide is in range of 2:5 to 6:1. This is an important aspect of the invention and works in concert with the Fischer-Tropsch 128 to provide the effective results realized by practicing the technology as discussed herein with respect to FIGS. 5 through 6 . Natural gas 188 , depending on the current market situation at any location or time, may be used as a primary feedstock to the hydrogen rich syngas generator 182 and the steams 174 , 130 and 184 may be used to maximize upgrader operation. Alternately, if the natural gas market is less favourable, streams 174 , 130 and 184 may be fully utilized to offset the need for natural gas. The hydrogen rich syngas 190 can be introduced in advance of the syngas treatment unit 90 at 190 if treatment is required, or alternately, any portion of the hydrogen rich syngas 190 may be routed directly to the Fischer-Tropsch unit 128 .
In this manner, the hydrogen rich syngas 190 is combined with the carbon rich syngas to create an optimum Fischer-Tropsch syngas where the ratio of the hydrogen to carbon monoxide is preferred 2:1. The combined feed streams to unit 122 reduces the amount of natural gas needed to achieve the optimum Fischer-Tropsch feed stream, thereby offering a commercial advantage of the upgraders dependence on natural gas, but also takes advantage of current low cost supply of natural gas.
Additionally, a portion of the hydrogen rich syngas 190 can be introduced to hydrogen unit 192 where a purified hydrogen stream 164 is generated for use in the hydroprocessing unit 108 and fractioning/hydrotreating unit 160 . The hydrogen unit 192 may consist of a pressure swing adsorption (PSA), membrane or absorption technology, well known to those skilled in the art.
Turning to FIG. 7 , the process flow diagram illustrates a further variation on the overall concept of the present invention and in this manner, the XTL unit 122 undergoes further variation where the hydrogen unit 192 and hydrogen rich syngas generator 182 inherent in the embodiment FIG. 6 are replaced with a water gas shift (WGS) reaction unit operation. The overall process of FIG. 7 is denoted by 200 . The water gas shift unit is denoted by 202 and is disposed between the syngas treatment unit 90 and the Fischer-Tropsch unit 128 processing at least a portion of the sour or sweet syngas. As is known in the art and particularly by those skilled, the water gas shift reactor is useful to enrich the raw syngas which, in turn, results in optimization of the hydrogen to carbon monoxide ratio for the Fischer-Tropsch syngas. Steam supply for the WGS reaction unit 202 may be provided from the gasifier 86 shown as 204 . Additionally, hydrogen rich gas 171 and 173 from the hydroprocessor units may be combined with the FT vapours 140 to enrich the FT syngas feed.
Referring now to FIG. 8 , shown schematically is an example of a conventional simple low conversion refinery 230 that would receive 30+API (light crude) crude oil, examples of which include Escravos 34 API and/or Bonny light 35 API at a volume of 100,000 BPD having 1600 ppm sulphur and 1178 ppm N2 with a specific gravity of 0.85, CCR of 1.4% by weight and 11 ppm nickel and vanadium content. This type of refinery targets the production of high value ultra lowsulfur (ULSG) gasoline and (ULSD) diesel and produces about 7 vol % of the crude feed as refinery bottoms, denoted as 284 . Such refineries are currently experiencing challenges in maintaining a market for products from low value refinery bottoms and typically convert the bottoms to road asphalt and/or fuel oil. Such refineries are facing continuing economic challenges in accessing low density crude (30+API) at competitive costs. To maintain commercial viability, these refineries pursue lower value discounted heavy oil (20 to 25 API) feedstocks to blend with conventional light 30+API crude. The addition of the heavier crude oil increases the production of undesirable refinery bottoms.
The light crude oil is treated in atmospheric distillation unit 82 with 35,010 BPD of atmospheric tower bottoms at 19.6 API being produced referenced by numeral 232 . From the ADU 82 , light straight run oil (LSR) 234 in an amount of 5,370 BPD at 80 API are generated along with 26,000 BPD of heavy straight run (HSR) 236 oil at an API of 48. Kerosene 238 is produced in an amount of 13,510 BPD at an API of 35.7 and diesel 240 at 31 API in an amount of 20,110 BPD.
The LSR 234 is then treated in a C5/C6 isomerization unit operation with the isomerate 244 collected for the refinery product slate 246 as gasoline blend stock. The HSR 236 is treated in a naphtha hydrotreating unit (NHTU) 248 and then in reformer 250 with the reformate 252 subsequently forming part of the slate 246 , also as gasoline blend stock.
The kerosene 238 is treated in a kerosene Merox unit 254 to remove sulfur with the ultra low sulfur kerosene/jet fuel 256 then forming part of the product slate 246 .
Diesel 240 is generated in an amount of 20,110 BPD with an API of 33. The diesel 240 is treated in a hydrotreating unit 258 to form (ULSD) ultra low sulfur diesel 260 , then forming part of the product slate 246 .
Returning to the atmospheric tower bottoms 232 , the material is treated in the vacuum distillation unit 110 to yield 19,330 BPD of 23 API light vacuum gas oil 262 and 8,990 BPD of 19 API heavy vacuum gas oil 264 . Each of these products is then treated in hydrotreating unit 266 to yield distillate 268 forming part of the product slate 246 with a portion of the naphtha formed from treatment in unit 266 passed into NHTU 248 . A further portion, namely gas oil 272 is treated in a (FCC) fluid catalytic cracking unit 274 for production of gasoline blends.
Unconverted light cycle oil (LCO) 276 exiting the FCC unit 274 is further blended and treated in unit 258 to synthesize further ultra low sulfur diesel 260 for slate 246 . Alkylates 278 , light gasoline 280 and heavy gasoline 282 are then passed into gasoline pool of the product slate 246 .
A portion 284 of the vacuum bottoms from unit 110 at 6,690 BPD and API density of 10.7 and containing 121 ppm (nickel and vanadium), together with 80 million standard cubic feet per day (MMSCFD) of natural gas 286 and oxygen 288 in an amount of 1400 tons per day (TPD) is treated in the Fischer-Tropsch unit, described as FTCrude unit to formulate synthetic hydrocarbon byproducts.
Such processing has been discussed herein previously. The resulting product streams of liquid petroleum gas (LPG) 292 , FT naphtha 294 , synthetic jet fuel 296 and synthetic diesel 298 are passed into the isomerisation unit 242 , unit 248 and product slate 246 , respectively. Slate 246 accepts both steams 296 and 298 , while stream 294 is optionally blended into feed to unit 248 , then reformer 250 prior to passage to gasoline pool in product slate 246 .
A supply of hydrogen in an amount of 40 MMSCFD also is produced from unit 122 for use in the hydroprocessing units.
A sulfur recovery unit 302 recovers 21.8 TPD of sulfur.
Subsequent to all of the operations, the slate 246 results in 1,500 BPD of C3/C4 liquid petroleum gas (LPG) 304 , 61,800 BPD of regular/premium gasoline (ULSG) 306 having an API of 55 and specific gravity of 0.76, 13,500 BPD of jet fuel 308 having an API of 36 and a specific gravity of 0.84, 38,400 BPD of ultra lowsulfur diesel (ULSD) 310 having an API of 41 and a specific gravity of 0.82. The volume % yield is 115% and the weight % yield is 100%.
Beneficially, the process results in:
a) significant high product yield supporting much improved refinery economics; b) full utilization of the heavy crude resources; c) lower refinery capital and operating costs; d) reduced environmental impact, lower GHG, eliminates heavy metals, sulfur, petcoke, heavy sour fuel oils, etc.; e) a refinery configuration which can handle heavier crude assay; and f) synthetic diesel quality of greater than 55 cetane, meeting most efficient diesel specification for high performance and high efficiency diesel engines.
In summary, the addition of a FTCrude unit receives the additional vacuum residue without the need to form undesirable fuel oil, petcoke or road asphalt and converts it to high value synthetic fuels such as synthetic diesel and synthetic jet fuel. Significant benefits are realized in that greater than 110 vol % product yield or more specifically greater than 115 vol % product yield can be achieved, without the production of unmarketable byproducts and with a 40 to 80% GHG reduction.
Turning to FIG. 9 illustrates an example of a typical medium conversion refinery that receives the entire crude feed as heavy oil (18 to 22 API) crude oil and targets production to ULSD diesel/jet fuel with the option for naphtha sales or further conversion to ULSD gasoline. FIG. 9 also illustrates the addition of a FTCrude or hydrocarbon synthesis unit to receive additional vacuum residue (approximately 24 vol % of the crude slate) and convert it to high value synthetic fuels such as synthetic diesel and synthetic jet fuel. Significant benefits are realized in that greater than 120 vol % product yield result or more specifically, 130 vol % product yield results, without the production of undesirable byproducts and with a 40 to 80% GHG reduction.
In greater detail of FIG. 9 , the overall process is denoted by numeral 312 . The refinery process uses a heavy crude oil as an initial feedstock, the heavy crude oil being denoted by numeral 314 in a volume of 100,000 BPD. In this example, the crude is Angola crude having an API of 22 with 0.7 weight percent sulfur with a specific gravity of 0.92 and a metal content of 94 parts per million (ppm) of nickel and vanadium. The heavy crude oil 314 is introduced into ADU unit 82 for processing. The processing steps are well known to those skilled in the art and will not be discussed herein. Subsequent to processing in the ADU unit 82 , the result is a stream of sweet fuel gas 316 , as well as a stream of straight run naphtha and light gas oil in a combined volume of 42,900 BPD with a specific gravity of 0.82 and an API of 41. The straight run naphtha and light gas oil is denoted by numeral 318 . A further stream of product is atmospheric bottoms in a volume of 57,100 BPD having an API of 19. This is denoted by numeral 320 . The atmospheric bottoms 320 are introduced into a vacuum distillation unit 110 with the result being vacuum gas oil 322 in a volume of 33,300 barrels per day (BPD) having a specific gravity of 0.92 and an API of 19 with 0.8 weight percent of sulfur and a CCR equivalent to 0.9 weight percent. Both the straight run naphtha and light gas oil 318 and the vacuum gas oil 322 are subsequently introduced separately or combined into the hydro-processing unit 108 . In the example, the hydro-processing unit 108 includes unit operations directed to hydrocracking and hydrotreating. This has been generally discussed herein previously with respect to the other embodiments. Subsequent to treatment in hydro-processing unit 108 , the naphtha that is produced, denoted by numeral 324 is introduced into a naphtha recovery unit 326 for stabilization and sulphur removal, where light vapour is subsequently passed into the fuel gas stream 316 for removal of further removal of sulfur (H2S) and use as refinery fuel. Similarly, second sour vapour stream 328 from the hydroprocessor units 108 is passed directed to the fuel gas stream 316 . All the LGO and VGO is converted and sweetened to primarily produce stream 330 exiting hydro-processing unit 108 as (ULSD) ultra-low sulfur diesel in a volume of 72,800 BPD at 33 API with less than 15 parts per million of sulfur and a specific gravity of 0.86. This is passed into the refinery product slate 246 . Similarly, stream 332 exiting naphtha recovery unit 326 comprises sweet, stabilized naphtha in a volume of 9,900 BPD having an API of 55 and a specific gravity of 0.76 and less than 30 parts per million of sulfur. This is also passed into the refinery product slate 246 or can be further processed by reforming to gasoline (not shown) as shown in FIG. 8 as unit 250 .
Returning to the vacuum distillation unit 110 , a stream 334 comprising a vacuum resid bottom volume of 23,800 BPD at an API of 5 and a specific gravity of 1.04 with a CCR equivalent to 19 weight percent and a sulfur content of 1.3 weight percent is introduced together with process oxygen 288 in an amount of 4,100 TPD and natural gas 286 in an amount of 300 MMSCFD into the FTCrude unit 122 . As has been delineated previously in the specification, the FTCrude unit involves XTL operations which include, but are not limited to gasification, syngas generation, the Fischer-Tropsch process unit and the Fischer-Tropsch upgrader. The FTCrude further provides through unit 122 a hydrogen stream 336 in the amount of 80 MMSCFD for use in the hydro-processing unit 108 . Product streams exiting the processing unit 122 include the FT LPG (not shown), FT naphtha 294 in an amount of 5,200 BPD having an API of 72 and a specific gravity of 0.69, FT diesel 298 in an amount of 43,400 BPD having an API of 53 and a specific gravity of 0.77, as well as FT process carbon dioxide in an amount of 2,700 tones per day as denoted by numeral 338 , FT sulfur in an amount of 51 TPD and FT process water in an estimated amount of 50,000 BPD.
As is illustrated in the flow diagram, the FT diesel 298 and FT naphtha 294 are passed to the product slate 246 . FT LPG is generally integrated into the refinery fuel supply.
The result of the refinery products stated in accordance with this embodiment of the present invention includes naphtha 344 in an amount of 15,100 BPD and an API of 60 and a specific gravity of 0.72 with less than 30 parts per million of sulfur, ultra-low sulfur (ULSD) diesel 346 in an amount of 69,700 BPD with an API of 43 and a specific gravity 0.81 with less than 15 parts per million of sulfur and optional ultra-low sulfur jet fuel 348 in an amount of 46,500 BPD with an API 50 and a specific gravity of 0.84 with less than 15 parts per million or ppm of sulfur. The volume percent yield for this process is 132% and the weight percent yield is 100%.
FIG. 10 illustrates an example of a deep conversion refinery that receives the entire crude feed as extra heavy oil (12 to 18 API) crude oil and/or bitumen (6 to 11 API) crude oil and primarily targets production of ULSD diesel and naphtha, with the option to further convert to ULSD gasoline. Extra heavy crude oil and bitumen are typically received at the upgrader as diluted crude referred to as DilBit. The diluent is recovered at the upgrader and returned to the crude provider. FIG. 10 also illustrates the addition of a FTCrude or hydrocarbon synthesis unit to receive the significant additional vacuum residue (approximately 60 vol % of the crude slate) and converts it to high value synthetic fuels such as synthetic diesel and synthetic jet fuel. As shown in FIG. 10 , it is preferred to further treat the vacuum residue with a solvent deasphalting unit, (SDA), capable of producing a clean deasphalted oil (DAO) for further hydroprocessing into high value diesel/jet products. A host of benefits are realized in that greater than 120 vol % product yield result or more specifically 137 vol % product yield results, without the production of undesirable byproducts and with a 40 to 80% GHG reduction. Generally, the increased product yield represents about 65+% product yield increase over conventional carbon rejection technologies, such as coking, and a 35+% product yield increase over conventional hydrogen addition technologies such as heavy reside hydrocracking.
In greater detail, in this embodiment the ADU unit 82 may receive an initial feedstock of dilbit 315 in an amount of 142,800 BPD with an API 21 and a specific gravity of 0.93, which contains bitumen 352 in an amount of 100,000 BPD having an API of 8.5 and a sulfur content of 4.5% by weight and a specific gravity of 1.02. Subsequent to treatment in the ADU unit 82 , the light vapours is taken off as stream 316 and subsequently treated for use a fuel and stream 318 comprises the combined straight run naphtha and light gas oil in an amount of 18,804 BPD at 44 API. In one embodiment of this invention, atmospheric bottoms is processed directly in a Solvent Deasphalting Unit (SDA) 84 , whereby deasphalted oil (DAO) 354 in an amount of 57,862 BPD at an API of 14 with a sulfur content of 4% by weight and a metals content of less than 20 ppm (nickel and vanadium) having a specific gravity of 0.97 and CCR equivalent of 3.3% by weight is produced as idea feed to a conventional hydrocracker unit. Streams 318 and 354 are optionally passed into the hydro-processing unit 108 with the produced naphtha 324 being stabilized and treated in naphtha recovery unit 326 and the vapours subsequently passed into sweet fuel gas 316 . In this embodiment, the naphtha stream 332 coming from naphtha recovery unit 326 is in the amount of 8,300 BPD at an API of 55 having a specific gravity of 0.76 with less than 30 ppm of sulfur which can optionally be further processed in a Reformer to be produced into gasoline, as previously discussed. The ultra-low sulfur (ULSD) diesel/jet fuel in a volume of 73,150 BPD having an API of 33 with a sulfur content of less than 15 parts per million (ppm) and a specific gravity of 0.86 is primarily produced from the hydroprocessing unit 108 . Both streams 332 and 330 are passed into a refinery product slate 246 .
In this embodiment, the arrangement includes a deasphalting unit 84 into which a stream 356 from unit 82 is introduced. The stream 356 comprises atmospheric bottoms in a volume of 85,092 BPD having an API of 7 with a 4.6 weight percent content of sulfur and a metals content of 340 ppm (nickel and vanadium) with a specific gravity of 1.02 and a CCR equivalent of 16.7 weight percent. In another embodiment of the present invention, the atmospheric bottoms can optionally be feed a vacuum distillation unit (VDU) and the subsequent vacuum bottoms can feed the SDA unit. From the SDA unit 84 , the stream 358 therefrom together with process oxygen 288 in an amount of 4,700 TPD and natural gas 286 in an amount of 370 MMSCFD is introduced into FTC crude unit 122 . Stream 358 comprises liquid asphaltene stream in an amount of 27,229 BPD having an API of -6 with a sulfur content of 6.2 percent per weight and a metals content of 730 ppm (nickel and vanadium) with a specific gravity of 1.4 and a CCR equivalent of 37 percent by weight. Subsequent to the treatment in unit 122 , the result is the production of, similar to the embodiment in FIG. 9 , the FT LPG (not shown), FT naphtha with a volume of 6,050 BPD at an API of 72 and a specific gravity of 0.69 as well as FT diesel 298 in an amount of 49,500 BPD having an API of 53 and a specific gravity of 0.77. To reiterate, streams 298 , 294 , 330 and 332 form the refinery product slate 246 and are blended or sold separately as high value refined products. The result of this is a naphtha content of 14,350 BPD with a 60 API and a specific gravity of 0.72 together with a sulfur content of less of 30 ppm, this being denoted by 344 , which may be optionally further reformed to produce gasoline or marketed as petrochemical feedstock. The slate also includes ultra-low sulfur (USLD) diesel 346 and a volume of 73,590 BPD with an API of 43 and a sulfur content of less than 15 ppm with a specific gravity of 0.81. The slate can further optionally include ultra-low sulfur jet fuel 348 in a volume of 49,060 BDP having an API of 50 and a sulfur content of less than 15 ppm with a specific gravity of 0.84. The volumes of diesel and jet fuel can be further optimized as is well known by those skilled in the art. In this process, the results of streams 338 , 340 and 324 are 2,700 TPD, 270 TPD and an estimate of 50,000 BPD, respectively.
It will be appreciated by those skilled in the art that the processes described herein provide a variety of possibilities for refining, partial upgrading or full upgrading, owing to the fact that the unit operations can be reconfigured to achieve the desired result. As an example, the bottoms fraction that is sent to the syngas generating circuit described herein previously can be used for formulating a hydrogen lean gas stream via a partial oxidation reaction. The reaction may be catalytic or non-catalytic. This reaction product can be then treated in a Fischer-Tropsch reactor to synthesize hydrocarbon byproducts while at least a portion of synthetic hydrocarbon byproducts can be removed for commercial market distribution.
While the preferred embodiments of the invention have been shown and described, modifications thereof can be made by one skilled in the art without departing from the spirit and teachings of the invention. Reactor design criteria, hydrocarbon processing equipment, and the like for any given implementation of the invention will be readily ascertainable to one of skill in the art based upon the disclosure herein. The embodiments described herein are exemplary only, and are not intended to be limiting. Many variations and modifications of the invention disclosed herein are possible and are within the scope of the invention. Use of the term “optionally” with respect to any element of a claim is intended to mean that the subject element is required, or alternatively, is not required. Both alternatives are intended to be within the scope of the claim.
Accordingly, the scope of protection is not limited by the description set out above, but is only limited by the claims which follow, that scope including all equivalents of the subject matter of the claims. Each and every claim is incorporated into the specification as an embodiment of the present invention. Thus the claims are a further description and are an addition to the preferred embodiments of the present invention. The discussion of a reference in the Background of the Invention is not an admission that it is prior art to the present invention, especially any reference that may have a publication date after the priority date of this application. The disclosures of all patents, patent applications and publications cited herein to the extent that they provide exemplary, procedural or other details supplementary to those set forth herein.
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A bitumen and heavy oil upgrading process and system is disclosed for the synthesis of hydrocarbons, an example of which is synthetic crude oil (SCO). The process advantageously avoids the waste attributed to residuum and/or petcoke formation which has a dramatic effect on the yield of hydrocarbon material generated. The process integrates Fischer-Tropsch technology with gasification and hydrogen rich gas stream generation. The hydrogen rich gas generation is conveniently effected using singly or in combination a hydrogen source, a hydrogen rich vapor from hydroprocessing and the Fischer-Tropsch process, a steam methane reformer (SMR) and autothermal reformer (ATR) or a combination of SMR/ATR. The feedstock for upgrading is distilled and the bottoms fraction is gasified and converted in a Fischer-Tropsch reactor. A resultant hydrogen lean syngas is then exposed to the hydrogen rich gas stream to optimize the formation of, for example, the synthetic crude oil.
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The present application is a continuation-in-part application of application Ser. No. 08/835,920 filed Apr. 10, 1997 now U.S. Pat. No. 5,795,911.
FIELD OF THE INVENTION
The present invention relates to methods for treating the hyperplasia caused by a papilloma virus, such as Condyloma acuminata or genital warts which involves administering an extract of tea containing catechins (camellia sinensus).
BACKGROUND OF THE INVENTION
Papilloma viruses comprise a DNA virus which infects epithelial cells of mammals and which causes uncontrolled cell replication. There are many types of papilloma virus which infect human and animal species, but they all can infect the basal epithelial cells and persist in an episome or as DNA integrated into the host genome. The mechanism by which they cause tissue growth may be related to the E4 and E5 proteins they all produce in related forms, which appear to interact with p54 and other host proteins which control the cell cycle. The effects of papilloma virus which have been described include genital warts or Condylomata acuminata, common warts, plantar warts, bovine papillomas, and cervical intra-epithelial neoplasia in women.
The detection of human papilloma virus ("HPV") in Condyloma acuminata involve a method of taking a tissue sample or a smear from the infected area and determining the DNA of the virus. According to this method, the detection rate is almost 100%.
Types HPV6 and 11 of the virus are the ones most commonly detected and because HPV16 has been detected in malignant squamous cell carcinoma from cancer of the penis, cancer of the cervix and Condyloma acuminata, there is a strong possibility that HPV16 is related to the malignancy of Condyloma acuminata.
Means for the treatment of Condyloma acuminata caused by human papilloma virus which have been tried include physical means such as surgical excision, electrocauterization, cryosurgery, laser therapy, etc., and medications such as applications of Podophyllin, 5-Fluorouracil, Bleomycin, Interferon, Imiquimod, etc., which are presently available. However, surgical treatment is distressing for the patient, considering the site of infection, and with topical applications there is the concern of side-effects. The aforesaid medications work either by cytotoxic tissue destruction or by enhancing the cellular immune response by causing local inflammation. Accordingly, a conclusive treatment has heretofore not been available.
Condyloma acuminata has a high rate of recurrence, and a complete cure is difficult unless treated constantly. Therefore, treatment which has a high degree of safety and is convenient strongly desired.
A treatment of Condyloma acuminata or other diseases caused by papilloma virus is desired which would be easy for the patient to take. For example, it would desirable to have a medication which can be applied to the affected area by the patients themselves and which would provide good results after a relatively short period of use and have no side-effects.
SUMMARY OF THE INVENTION
The present inventors searched for a natural substance which has no side-effects, may be safely applied for a long period of time by the patients themselves and is notably effective. After extensive testing, the inventors discovered that catechin, a component of tea which is an everyday beverage, is effective for treating hyperplasia caused by papilloma virus, and thus the present invention was developed.
Accordingly, the present invention relates to a method for the treatment of hyperplasia caused by papilloma virus, comprising administering to a human an effective anti-hyperplasia amount of a tea extract containing catechin as a main component. More specifically, the present invention concerns the treatment of Condyloma acuminata, common warts, plantar warts and cervical infra-epithelial neoplasia by local administration i.e., topical administration, or oral administration, or a combination of topical and oral administration of tea catechin.
DETAILED DESCRIPTION OF THE INVENTION
The tea catechin for use in the present invention is shown below in the following formula I ##STR1## wherein R 1 represents H or OH and R 2 represents H or ##STR2##
The tea catechins are more specifically, epicatechin, epicatechin gallate, epigallocatechin gallate, gallocatechin, etc. (including derivatives thereof). These catechins can be used singly, or two or more may be mixed together. Out of these it is particularly desirable to have (-)-epigallocatechin gallate as a main component. Examples of tea catechin compositions for use in the present invention include the following: POLYPHENON 100™ (produced by Mitsui Norin Co.; Composition: (+)-gallocatechin 1.44%, (-)-epicatechin 5.81%, (-)-epigallocatechin 17.57%, (-)-epicatechin gallate 12.51%, (-)-epigallocatechin gallate 53.90w; or POLYPHENON E™ (produced by Mitsui Norin Co.; Composition: (-)-epicatechin 10.8%, (-)-epigallocatechin 9.2%, (-)-epicatechin gallate 6.5%, (-)-epigallocatechin gallate 54.8%, (-)-gallocatechin gallate 4.0%).
The tea catechin or tea catechin composition for the treatment of, for example, Condyloma acuminata, of the present invention could be used, for example, in the form of an ointment such as a cream, a jelly, or an emulsion; or in the form of a suppository such as a capsule, and usually the tea catechin component is combined with an excipient, an extending agent, an emulsifier, a dispersing agent, etc. Vaseline is suitable as a base for the ointment. For the ointment, the content of tea catechin should be between 2-20% by weight, preferably between 12-18% by weight, and more preferably 15% by weight. In the case of a suppository, the content of tea catechin should be 50-500 mg/capsule, preferably 200-300mg/capsule, or more preferably 250mg/capsule.
A typical usage example for the ointment is to apply the ointment directly to the infected area of the external genital organs or vagina, a vaseline cream containing 2-20% by weight catechin, from once to several times everyday for a period of 1-2 months. A typical usage example for the suppository in the case where, for example, the infected area is the cervix or the vagina, is to insert a capsule containing 50-500mg tea catechin, from once to several times everyday for a period of 1-2 months.
There is no danger of side-effects from the use of tea catechins for the treatment of, for example, Condyloma acuminata, since the tea catechins are natural substances derived from tea, which is commonly consumed regularly, and it may be taken for long periods of time. Moreover this medication may be easily applied to or inserted in the infected area by the patients themselves. The composition of the present invention for a treatment of, for example, Condyloma acuminata, has a very high potential for practical use.
The tea catechin compounds utilized in the present invention can be administered orally in the form of tablets, capsules, granules, powders or syrups. The pharmaceutical preparations for oral administration can be produced in a conventional manner using adjuvants that are generally known in the art, such as excipients, binders, disintegrating agents, lubricants, stabilizers, corrigents and the like. Although the dosage may vary depending upon the symptoms and age of the patient, the nature and severity of the disease or disorder, in the case of oral administration to an adult human patient, the tea catechin compounds used in the present invention may normally be administered at a total daily dose of from 100 to 2,000 mg, either in a single dose, or in divided doses, for example, two or three times a day.
EXAMPLES
The present invention will be explained in more detail with reference to the following examples which are in no way meant to limit the scope of the invention.
Test Example 1
An ointment consisting essentially of a vaseline based vaginal lubricant containing, as the main component, tea catechin (Trade name: "POLYPHENON 100", produced by Mitsui Norin Co. Ltd., its main component: (-)-epigallocatechin gallate) was applied to the cervix of healthy mice (50 mice in a group) in catechin dosages of 8mg, 15mg, and 38mg for a period of 7 consecutive days. After this time, pathological and histological examinations were carried out and it was determined that except for a mild inflammatory reaction in the cervix of the group of mice administered with the 38mg dose, no toxic effect was observed.
Example 1
Clinical tests of the present invention were carried out at the Cancer Institute, Chinese Academy of Medical Sciences in Beijing, China, with a group of 11 women who had been diagnosed with HPV-infected Condyloma acuminata. All patients were confirmed to have Condyloma in the vulva (external genital organs) and cervix according to clinical examination, cytologic, colposcopic and pathologic tests. Warts were from 0.2 to 2cm in diameter.
Tests were carried out on these 11 patients using either a vaseline-based ointment containing 10 wt % of tea catechin (Trade name: "POLYPHENON 100", produced by Mitsui Norin co., Ltd., crude catechin content is about 90 weight % and its main component is (-)-epigallocatechin gallate) or using a suppository containing 300 mg/capsule of the above tea catechin. Applying the ointment to the external genital organs and applying the suppository to the cervix, the treatments of the present invention were used continuously once a day for about two months.
During the period of treatment, examinations and colposcopic tests of the infected areas were carried out. Results obtained are shown in Table 1. As shown in Table 1 hereinbelow, when the infected area completely disappeared it was judged to be cured, when 50% or more disappeared, it was judged to be improved and when less than 50% or nothing disappeared, it was judged that there was no effect.
TABLE 1______________________________________ No. ofInfected Area Patients Cured Improved No Effect______________________________________External 9 4 3 2genital organsCervix 2 1 0 1______________________________________
As is evident from Table 1, 7 cases out of 9 (77.8%) of Condyloma acuminata of the external genital organ showed a clear effect (being either cured or improved). In one case of the cervical infection, the tumor completely disappeared, and thus was cured. During this period, apart from some patients who experienced slight pain or inflammation in the infected area and a few other patients who felt some itching, there were no obvious side-effects observed.
Example 2
The clinical tests at the Cancer Institute, Chinese Academy of Medical Sciences in Beijing, China were conducted in the same manner as in Example 1, using a vaseline-based ointment containing 15 weight % tea catechin on external and internal warts, with a group of 33 female patients diagnosed with HPV-infected Condyloma acuminata. In this group, 8 of the patients were infected in two areas. Results are shown in Table 2 hereinbelow. As is evident from Table 2, 92% of Condyloma acuminata of the external genital organs and 70% of the vaginal Condyloma acuminata were cured or improved, and in the case of the cervical Condyloma acuminata, all cases were cured. 25 cases out of 41 cases showed were cured, and the curing ratio was 61%.
TABLE 2______________________________________ No. ofInfected Area Patients Cured Improved No Effect______________________________________External 26 18 6 2genital organsVagina 10 2 5 3Cervix 5 5 0 0Total (%) 41 25 11 5 (61.0) (26.8) (12.2)______________________________________
Example 3
The clinical tests at the Cancer Institute, Chinese Academy of Medical Sciences in Beijing, China were conducted in the same manner as in Example 2, except that the ointment contained 15 weight % of a different tea extract ("POLYPHENOL E", produced by Mitsui Norin Co., Ltd., which is similar to "POLYPHENOL 100"; the crude catechin content of "POLYPHENOL E" is about 82 weight %, and its main component is (-)-epigallocatechin gallate) with a group of 22 female patients diagnosed with HPV-infected Condyloma acuminata. Results are shown in Table 3 hereinbelow. As is evident from Table 3, out of 16 cases of Condyloma acuminata of the external genital organs, 7 were cured and 6 improved; a total of 13 (81.3%) being effected. In the case of Condyloma acuminata of the vagina, out of 6 cases 3 were cured and 2 were improved; a total of 83.3% was confirmed to be effected.
TABLE 3______________________________________ No. ofInfected Area Patients Cured Improved No Effect______________________________________External 16 7 6 3genital organsVagina 6 3 2 1Total (%) 22 10 8 4 (45.5) (36.4) (18.2)______________________________________
The entire disclosure of Japanese Patent Application No. 8-321195 filed on Nov. 18, 1996, including the specification, claims and summary, is incorporated herein by reference in its entirety.
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A method for a treatment of hyperplasia caused by papilloma virus, such as for treating Condyloma acuminata which comprises administering tea catechin. Tea catechins do not involve the risk of side-effects and may be easily applied to or inserted in the infected area by the patients themselves.
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RELATED APPLICATION
[0001] This application claims benefit under 35 U.S.C. §119(e) of U.S. Provisional Application Ser. No. 61/709,895, titled “A System For Thermoelectric Energy Generation,” Attorney's Docket 017083.0341, tiled Oct. 4, 2012, by Joshua E. Moczygemba and U.S. Provisional Application Ser. No. 61/745,413, titled “A System For Thermoelectric Energy Generation,” Attorney's Docket 017083.0343, filed Dec. 21, 2012, by Joshua E. Moczygemba,
TECHNICAL FIELD
[0002] This disclosure relates to generally to energy generation and more particularly to a system for thermoelectric energy generation.
BACKGROUND
[0003] The basic theory and operation of thermoelectric devices has been developed for many years. Presently available thermoelectric devices used for cooling typically include an array of thermocouples that operate in accordance with the Peltier effect. Thermoelectric devices may also be used for heating, power generation, and temperature sensing.
[0004] A thermoelectric device produces electrical power from heat flow across a temperature gradient. As the heat flows from hot to cold, free charge carriers in the thermoelectric material are also driven to the cold end. The resulting voltage is proportional to the temperature difference via the Seebeck coefficient.
SUMMARY
[0005] In one embodiment, a system includes a first plate and a second plate. The first plate is arranged to be thermally coupled to a first surface and the second plate is arranged to be thermally coupled to an environment. The environment has a temperature that is different than the first surface. The system also includes a thermoelectric device that includes a plurality of thermoelectric elements. The thermoelectric device includes a third plate coupled to the plurality of thermoelectric elements and thermally coupled to the first plate. The thermoelectric device also includes a fourth plate coupled to the plurality of thermoelectric elements and thermally coupled to the second plate. The system also include sa dielectric fluid arranged between the first plate and the second plate. The thermoelectric elements are submersed in the dielectric fluid.
[0006] In some embodiments, a gasket may be situated within a groove of the first plate. The system may include a wall situated between the first plate and the second plate. The wall may be situated around the thermoelectric device. The wall may include thermally insulative material.
[0007] In one embodiment, a method includes thermally coupling a first plate to a first surface and thermally coupling a second plate to an environment. The environment has a temperature that is different than the first surface. The method further includes generating electricity using a thermoelectric device based on a temperature gradient between the first plate and the second plate. The thermoelectric device includes a plurality of thermoelectric elements submersed in a dielectric fluid. The thermoelectric device also includes a third plate coupled to the plurality of thermoelectric elements and thermally coupled to the first plate as well as a fourth plate coupled to the plurality of thermoelectric elements and thermally coupled to the second plate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Reference is now made to the following description taken in conjunction with the accompanying drawings, wherein like reference numbers represent like parts.
[0009] FIGS. 1A and 1B illustrate one embodiment of a system that is configured to generate electric energy.
[0010] FIG. 2 is an exploded view of one embodiment of a thermoelectric generator.
[0011] FIG. 3 is a side view of one embodiment of a thermoelectric generator including a diaphragm.
[0012] FIG. 4 is a side view of one embodiment of a thermoelectric generator that incorporates a fin.
[0013] FIG. 5 is a side view of one embodiment of a thermoelectric generator that incorporates an electronic device.
[0014] FIG. 6 illustrates one embodiment of a thermoelectric device.
[0015] FIGS. 7A and 7B are a set of charts depicting examples of performance characteristics of embodiments of thermoelectric generators.
DETAILED DESCRIPTION
[0016] FIGS. 1A and 1B illustrate one embodiment of system 100 that is configured to generate electrical energy. In some embodiments, pipe 120 is in a high pressure (e.g., 100-10,000 psi) environment 140 (e.g., deep sea water, such as 10,000 feet below sea level at approximately 40 degrees Fahrenheit) and contains a hot (e.g., between 100 and 300 degrees Fahrenheit) medium (e.g., liquid or gas). As such, there is a temperature gradient between pipe 120 and environment 140 (e.g., a gradient between 50 and 200 degrees Fahrenheit). Thermoelectric generator 110 is situated such that one side of generator 110 is thermally coupled to pipe 120 (e.g., by being secured directly to pipe 120 or with suitable thermal interface materials such as graphite pads, grafoil, or other thermal pads situated between pipe 120 and generator 110 ) while another side of generator 110 is exposed to environment 140 . Thermoelectric generator 110 is situated inside insulation 130 that covers pipe 120 such that a side of generator 110 is still exposed to environment 140 (as depicted in FIG. 1B ). Thermoelectric generator 110 is configured to generate electricity based on the temperature difference between pipe 120 and environment 140 using the Seebeck effect. In some embodiments, generator 110 may be a reliable source of electrical energy suitable to power electronics such as sensors due to the near constant temperature difference between pipe 120 and environment 140 . In some embodiments, pipe 120 may contain a cold medium and environmental 140 may be hot; thermoelectric generator 110 may provide electrical energy in this situation due to the temperature difference between pipe 120 and environment 140 .
[0017] In some embodiments, high pressure environment 140 may include environments such as deep sea water. Another example of environment 140 is the interior of a pressure vessel. Yet another example of environment 140 is the interior of a pipeline. Thus, while the present disclosure discusses deep sea water as an example environment, the disclosure is applicable in other environments, such as those that have higher than normal pressure and those that lead to temperature gradients between the environment and devices in the environment.
[0018] In some embodiments, system 100 may be a continuous power source designed to harvest thermal energy (e.g., from subsea pipelines). The large temperature gradients between the pipelines and water may facilitate sustained, long term thermal energy harvesting. An example utility of this is avoiding battery replacement which may not be an economical option in such an environment. Example advantages of embodiments of system 100 are that system 100 may provide perpetual or continual, no maintenance power for subsea or deep sea applications. As another example, system 100 can be used to implement a sustainable, low-cost solution to monitoring ocean floor pipelines. Typically, ocean floor pipelines are costly to monitor and repair, especially after they have been substantially damaged. Using system 100 , problems may be detected beforehand and costly repairs can be avoided. For example, electrical energy produced by system 100 can then be used to power low-power electronics that can be used to monitor a pipeline in a convenient package which can be attached to the pipeline during a field jointing process.
[0019] FIG. 2 is an exploded view of one embodiment of thermoelectric generator 200 that may be used to implement thermoelectric generator 110 of FIGS. 1A and 1B . Cold side plate 230 is fastened to hot side plate 280 using fasteners 220 (e.g., nails, screws, and/or rivets). Thermoelectric device 250 is situated between plates 230 and 280 such that one side of thermoelectric device 250 is thermally coupled to plate 230 while another side of thermoelectric device 250 is thermally coupled to plate 280 . Immediately surrounding thermoelectric device 250 is wall 260 . Plates 230 and 280 as well as wall 260 may have grooves that are configured to receive gaskets 240 and 270 . Plate 230 may also include an orifice that allows for fluid to be poured into generator 200 once it is assembled and that orifice may be sealed using plug 210 .
[0020] In some embodiments, plates 230 and 280 can be titanium, stainless steel, aluminium, 90Cu10Ni alloy, or any bare or coated metal. In some embodiments, plates 230 and 280 may provide long term protection against sea water. In some embodiments, exterior sided edge insulation (suck as insulation 130 ) may be placed around the side edges of the housing (e.g., around plates 230 and 280 ) to further insulate thermoelectric generator 200 from thermal shorting (e.g., due to sea water in applicable circumstances).
[0021] In some embodiments, gaskets 240 and 270 may be hydraulic gaskets. Materials such as viton, nitrile, hydrogenated nitrile, fluorsilicone, epdm, silicone may be employed to form gaskets 240 and 270 . Gaskets 240 and 270 may prevent mixing of hydraulic fluid and sea water.
[0022] In some embodiments, wall 260 may be a low conductivity wall. For example, thermally insulative materials (e.g., polysulfone, Teflon, polycarbonate, nitrile, acrylic) may be used to form wall 260 . This may reduce, minimize, or prevent thermal shorting from the hot side to the cold side of thermoelectric generator 200 . This can be used to help force heat through thermoelectric device 250 .
[0023] In some embodiments, thermoelectric generator 200 may produce electrical energy when a temperature difference exists between plates 230 and 280 . Gaskets 240 and 270 may allow generator 200 to operate in aquatic environments such as deep sea water. Wall 260 may allow generator 200 to operate in the presence of high pressure such as those encountered in deep sea water. An example advantage is that gaskets 240 and 270 as well as low pressure differences between the inside of thermoelectric generator 200 and its environment may allow for using materials with low thermal conductivity to reduce or minimize reduction in performance due to thermal shorting. Another example advantage is that thermal shorting effects through housing of thermoelectric generator 200 may be reduced. For example, materials used for plates 230 and 280 as well as wall 260 can be chosen to avoid thermal shorting. As another example, thermal shorting can be avoided by allowing for plates 230 and 280 to have different shapes and thicknesses than what is typically used in high pressure environments.
[0024] In some embodiments, a configuration of thermoelectric generator 200 may eliminate wall 260 as well as gaskets 240 and 270 and replace them with a single hydraulic gasket. The size, shape and material of this single hydraulic gasket could be tailored to minimize conduction between plates 230 and 280 . One or more thin layers of dielectric hydraulic fluid (e.g., mineral oil, silicone oil, or vegetable oil) may serve as thermal interfaces between thermoelectric device 250 and plates 230 and 280 . In some embodiments, graphite pads, grafoil, or other thermal pads may serve as thermal interfaces between thermoelectric device 250 and plates 230 and 280 . Dielectric hydraulic fluids may be used in combination with thermal pads as thermal interfaces between thermoelectric device 250 and plates 230 and 280 .
[0025] FIG. 3 is a side view of one embodiment of thermoelectric generator 300 . Thermoelectric generator (“TEG”) 300 may be used to implement thermoelectric generator 200 of FIG. 2 and thermoelectric generator 110 of FIGS. 1A and 1B . Cold side plate 310 i fastened to hot side plate 320 using fastener 340 through channel 330 . Thermoelectric device 380 is situated between plates 310 and 320 such that one side of thermoelectric device 380 is thermally coupled to plate 310 and another side of thermoelectric device 380 is thermally coupled to plate 320 . Orifice 350 provides a manner in which to introduce substances into thermoelectric generator 300 such as fluid 390 . Orifice 350 is sealed using plug 360 . Diaphragm 370 may interface with plug 360 . Some or all of the spaces between and/or around thermoelectric elements of thermoelectric device 380 may include baffles 385 (e.g., open cell hexagonal strips). In some embodiments, thermoelectric generator 300 can handle very large isostatic pressures. Testing has shown that 10,000 psi under isostatic conditions poses no significant change to performance of thermoelectric device 380 .
[0026] In some embodiments, diaphragm 370 can allow for pressure equalization in the event air is trapped in the interior portion of the block. One mechanism by which this could occur with thermoelectric modules is the collapsing or air pockets entrained in solder joints as isostatic pressure increases. In such a case, diaphragm 370 would be sized so as to compensate for he change in internal volume of housing in TEG 300 . Diaphragm 370 would then displace, rather than housing of TEG 300 needing to support, the pressure differential.
[0027] In some embodiments, fluid 390 may be a low thermal conductivity, dielectric, incompressible fluid. In some embodiments, a fluid counteracts the external pressure of the seawater at large depths (reducing the need for thick walls for housing of TEG 300 ) and evenly distributes the pressure to every surface of the TEG module. For example, a hollow egg crushes quickly at low depth, but the same egg completely filled with an incompressible fluid could be submerged to large depths (e.g., the bottom of the Marianas Trench) without rupture. Also, since fluid 390 has a low thermal conductivity, transfer of heat from hot pipe to cold plate through the fluid is minimized. In some embodiments, the need for thick housing walls and strong materials is also reduced, significantly reducing thermal bypass through these walls (around TEG 300 ) from hot to cold side. In some embodiments, such a design significantly increases power output of TEG 300 (because the excess heat does not saturate the cold plate). Fluid 390 may be a hydraulic fluid (e.g., k=0.13 W/m-K), such as mineral oil, silicone oil, or vegetable oil to minimize thermal conductions losses through fluid 390 from hot to cold reservoirs. In some embodiments, liquid 390 may include a low thermal conductivity, non-compressible filer (e.g., a powder that is incompressible and not electrically conductive such as aluminum oxide, silicate, or ceramic type powders) or other suitable alternatives. The filler can be used to prevent convection currents. Also, a thin layer of fluid 390 can serve to aid or replace thermal interface material between thermoelectric device 380 and plates 310 and 320 thereby reducing the thermal interface contact resistance.
[0028] In some embodiments, thermoelectric generator 300 includes aspects that may facilitate generation of electric energy in high pressure environments such as deep sea water based on temperature differences between plates 310 ad 320 . For example, dielectric fluid 390 may be used to alleviate differential pressures. As another example, baffles 385 and/or filler material may be used to suppress convection currents.
[0029] FIG. 4 is a side view of one embodiment of thermoelectric generator (“TEG”) 400 that incorporates fin 440 . Thermoelectric generator 400 may be used to implement thermoelectric generator 200 of FIG. 2 and thermoelectric generator 110 of FIGS. 1A and 1B . Cold side plate 410 and hot side plate 420 are each thermally coupled to different sides of thermoelectric device 430 . Fin 440 is situated on cold side plate 410 and may assist in heat transfer to the environment in which thermoelectric generator 400 is situated (e.g., deep sea water).
[0030] In some embodiments, fin 440 may be any fixture capable of increasing the surface area over which TEG 400 may exchange thermal energy with its environment. For example, fin 440 may be a zipped or stacked fin heat exchanger comprising a plurality of closely-spaced fins separated from one another by a series of spaces. Each fin may include one or more flanges or other features operable to interlock the plurality of fins together into a single, unitary array. For example, flanges may be a series of frusto-conically-shaped perforations in fin 440 that are nested inside one another to link each of the individual fins together. Fin 440 may include a plurality of zipped fin structures, with each having a flat bottom coupled to a plurality of parallel fins. Fin 440 may be implemented using extrusion or skiving processes. Fin 440 may be a folded fin structure comprising a single sheet of material that has been consecutively folded over onto itself to create a single array of closely spaced fins. Fin 440 may include a lateral (e.g., generally L-shaped) fold at one end that, when aggregated together, form a flat.
[0031] FIG. 5 is a side view of one embodiment of thermoelectric generator 500 that incorporates an electronic device. Cold side plate 510 and hot side plate 520 are each thermally coupled to different sides of thermoelectric devices 530 . Electrical energy is generated by thermoelectric device 530 as a result of temperature differences between plates 510 and 520 and can be directed to electronic component 550 via leads 540 a - b . Electronic component 550 is situated within cold side plate 510 . Examples of electronic component 550 include circuit boards, power storage, sensors, and transmitters.
[0032] FIG. 6 illustrates one embodiment of thermoelectric device 600 that may be used to implement thermoelectric device 250 of FIG. 2 , thermoelectric device 380 of FIG. 3 , thermoelectric device 430 of FIG. 4 , and thermoelectric device 530 of FIG. 5 . Thermoelectric device 600 includes a plurality of thermoelectric elements 630 disposed between plates 610 and 620 . Electrical terminals 640 and 650 are provided to allow thermoelectric device 600 to be electrically coupled with to one or more devices that use, transform, or store electrical power.
[0033] In some embodiments, thermoelectric elements 630 fabricated from dissimilar semiconductor materials such as N-type thermoelectric elements and P-type thermoelectric elements. Thermoelectric elements 630 are typically configured in a generally alternating N-type element to P-type element arrangement and typically include an air gap disposed between adjacent N-type and P-type elements. In many thermoelectric devices, thermoelectric materials with dissimilar characteristics are connected electrically in series and thermally in parallel.
[0034] Examples of thermoelectric devices and methods of fabrication are shown in U.S. Pat. No. 5,064,476 titled Thermoelectric Cooler and Fabrication Methods; U.S. Pat. No. 5,171,372 titled Thermoelectric Cooler and Fabrication Method; and U.S. Pat. No. 5,576,512 titled Thermoelectric Apparatus for Use With Multiple Power Sources and Method of Operation.
[0035] N-type semiconductor materials generally have more electrons than would be found in the associated ideal crystal lattice structure. P-type semiconductor materials generally have fewer electrons than would be found in the associated ideal crystal lattice structure. The “missing electrons” are sometimes referred to as “holes.” The extra electrons and extra holes are sometimes referred to as “carriers.” The extra electrons in N-type semiconductor materials and the extra holes in P-type semiconductor materials are the agents or carriers that transport or move heat energy between plates 610 and 620 through thermoelectric elements 630 when subject to a DC voltage potential. These same agents or carriers may generate electrical power when an appropriate temperature difference is present between plates 610 and 620 . Terminals 640 and 650 may be coupled to one of plates 610 and 620 in a manner that withstands high temperature environments, such as resistance welding, tungsten inert gas (TIG) welding, and laser welding.
[0036] In some embodiments, thermoelectric elements 630 may include high temperature thermoelectric material. Examples of high temperature thermoelectric materials include lead telluride (PbTe), lead germanium telluride (PbxGel-xTe), TAGS alloys (such as (GeTE)0.85(AgSbTe2)0.15), bismuth telluride (Bi2Te3) based alloys, and skutterudies.
[0037] In some embodiments, thermoelectric elements 630 may include a diffusion barrier that includes refractory metals (e.g., a metal with a melting point above 1,850° C.). Suitable refractory metals may include those that are metallurgically compatible with high temperature thermoelectric materials and metallurgically compatible with other components of thermoelectric device 600 . For example, a molybdenum diffusion barrier may be used. This may be advantageous in that molybdenum may be metallurgically compatible with various aspects of thermoelectric device 600 . For example, as further discussed below, thermoelectric device 600 may include an aluminum braze that is metallurgically compatible with a molybdenum diffusion barrier. Such a diffusion barrier may prevent or reduce the change or occurrence of Kirkendall voiding in thermoelectric device 600 . Other suitable examples of diffusion barrier materials that could have similar properties to molybdenum include tungsten and titanium.
[0038] In some embodiments, alternating thermoelectric elements 630 of N-type and P-type semiconductor materials may have their ends connected by electrical conductors. Conductors may be metallization formed on thermoelectric elements 630 and/or on the interior surfaces of plates 610 and 620 . Conductors may include aluminum. Ceramic materials may be included in plates 610 and 620 which define in part the cold side and hot side, respectively, of thermoelectric device 600 . In some embodiments, the ceramic materials may provide electrical isolation from hot and cold side sources. Aluminum metallized ceramics may accommodate thermal stresses (i.e., due to high temperature exposure) of the ceramic/aluminum bond. Examples of suitable ceramic materials include anodized aluminum, aluminum oxide, aluminum nitride, and beryllium oxide.
[0039] In some embodiments, thermoelectric elements 630 may be coupled to plates 610 and 620 using a medium. The medium may include brazes and/or solders. For example, aluminum-based brazes and/or solders may be used, such as aluminum-silicon (Al—Si) braze family and/or zinc-aluminum (Zn—Al) solder. In some embodiments, using such brazes and/or solders may provide for high temperature operation and allow for flexible joints. Kirkendall voiding may be prevented or reduced.
[0040] FIGS. 7A and 7B are a set of charts depicting examples of performance characteristics (based on models and experiments) of embodiments of thermoelectric generators configured as described above with respect to FIGS. 1A-6 . Chart 700 depicts power output (both of a model and experimental results) of a thermoelectric generator, such as thermoelectric generator 110 of FIG. 1A , as a result of the amount of temperature difference present (e.g., the difference in temperature between pipe 120 and environment 140 of FIG. 1A ). The following table provides examples of the values used in chart 700 :
[0000]
Temperature
Power
Model
Difference (F.)
(Watts)
(Watts)
200.192
1.067
1.050
200.176
1.066
1.050
158.731
0.707
0.691
157.284
0.696
0.679
128.209
0.474
0.465
94.964
0.268
0.262
73.661
0.164
0.160
54.983
0.093
0.090
45.232
0.063
0.061
44.779
0.062
0.060
32.362
0.033
0.032
32.011
0.032
0.031
25.349
0.020
0.019
25.103
0.020
0.019
21.568
0.015
0.014
21.353
0.014
0.014
17.838
0.010
0.010
13.450
0.006
0.006
10.690
0.004
0.003
7.576
0.002
0.002
5.546
0.001
0.001
3.719
0.001
0.000
2.878
0.000
0.000
[0041] Charts 710 and 720 indicate power outputs of a thermoelectric generator, such as thermoelectric generator 110 of FIG. 1A , as compared to the temperature of a pipe (e.g., pipe 120 of FIG. 1A ) to which the thermoelectric generator is attached. Chart 710 is the result of experiments where ice water (“ICE”), at 4.44 degrees Celsius, is used and where room temperature (“RT”) water, at 25 degrees Celsius, is used. The following tables provide examples of the values used in chart 710 :
[0000]
Ice
Pipe Temperature
Power
(F.)
(Watts)
42.8
0.0
49.6
0.001
67.1
0.009
80.6
0.021
98.6
0.047
103.6
0.057
108.5
0.067
120.2
0.095
131.0
0.125
152.6
0.196
162.5
0.233
176.5
0.288
196.3
0.371
210.7
0.435
225.5
0.505
260.2
0.681
[0000]
Room Temperature
Pipe Temperature
Power
(F.)
(Watts)
42.8
0.000
49.6
0.000
67.1
0.000
80.6
0.000
98.6
0.008
103.6
0.012
108.5
0.016
120.2
.095
131.0
0.049
152.6
0.097
162.5
0.125
176.5
0.170
196.3
0.244
210.7
0.304
225.5
0.372
260.2
0.543
[0042] Chart 720 is the result of experiments where water at 40 degrees Fahrenheit is used. The following table provides examples of the values used in chart 720 :
[0000]
Pipe Temperature
Power
(F.)
(Watts)
266
0.551
230
0.403
194
0.272
158
0.157
122
0.071
86
0.018
[0043] Depending on the specific features implemented, particular embodiments may exhibit some, none, or all of the following technical advantages. By enabling deep sea operation, TEG energy harvesting may be a solution for deep water monitoring of oil pipe lines. A housing for a thermoelectric generator that can withstand significant amount of pressure yet also allow heat to be transferred through a thermoelectric device has been described. Other technical advantages will be readily apparent to one skilled in the art from the preceding figures and description as well as the proceeding claims and appendices. Particular embodiments may provide or include all the advantages disclosed, particular embodiments may provide none of the advantages disclosed.
[0044] Although several embodiments have been illustrated and described in detail, it will be recognized that modifications and substitutions are possible.
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A system includes a first plate and a second plate. The first plate is arranged to be thermally coupled to a first surface and the second plate is arranged to be thermally coupled to an environment. The environment has a temperature that is different than the first surface. The system also includes a thermoelectric device that includes a plurality of thermoelectric elements. The thermoelectric device includes a third plate coupled to the plurality of thermoelectric elements and thermally coupled to the first plate. The thermoelectric device also includes a fourth plate coupled to the plurality of thermoelectric elements and thermally coupled to the second plate. The system also includes a dielectric fluid arranged between the first plate and the second plate. The thermoelectric elements are submersed in the dielectric fluid.
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BACKGROUND AND SUMMARY OF THE INVENTION
This invention relates to emission controls for vehicles powered by internal combustion engines and in particular to the filtering of particulates from engine exhaust gases and more specifically, to the periodic incineration of the collected particulates in the filter through a temporary increase in the exhaust gas temperature by backpressuring of the engine.
Federal and State governments have adopted stringent new standards for particulate emissions for all diesel powered road vehicles. These new standards necessitate a device in the diesel engine exhaust system for removal of the particulates. Such exhaust treatment systems typically consist of a particulate trap to collect particulates from the exhaust gas stream during engine operation. Such particulates consist largely of carbon and heavy hydrocarbon particles which, with continued operation, tend to plug the exhaust filter, causing a restriction to the normal exhaust gas flow. Periodic cleaning of the particles from the exhaust gas filter is required in order to avoid the increase in the engine exhaust backpressure which adversely affects the fuel economy and vehicle performance.
In order to burn the filtered particulate it is necessary to increase the exhaust gas temperature in the filter or trap. Under typical operation, diesel engine exhaust temperatures high enough to burn the particulate are not experienced for sufficient time periods to clean the trap. Therefore, either a separate device is required to provide sufficient heat to burn the accumulated particulates or a separate means of obtaining increased exhaust gas temperatures must be found.
One means for increasing the exhaust gas temperature is to use a burner upstream of the filter. This may be accomplished by any practical burner mechanism such as the mechanism disclosed in the copending U.S. patent application Ser. No. 794,346, filed on Nov. 1, 1985 and entitled "Diesel Engine Particulate Trap Regeneration System". However, burners have several disadvantages, which include the use of additional fuel, the pumping transport and injection of that fuel and the general problems of stable combustion at low pressures.
The present invention has been developed to eliminate the need for a burner device to be used in cooperation with the particulate filter. According to the apparatus of the present invention, a particulate trap regeneration system used in association with a turbocharged or naturally aspirated engine comprises an exhaust gas particulate trap within the engine exhaust system downstream of the engine, a backpressuring valve within the engine exhaust gas flow downstream of said engine, an actuator to control the movement of the backpressure valve and a microprocessor for receiving relevant engine operating parameters from sensors and controlling the actuator. Under normal operating procedure, the backpressure valve remains in a wide open position. However, when the particulate trap pressure drop reaches a value indicating a significant amount of particles are present, as sensed by the microprocessor, the backpressure valve is partially closed. At this time the microprocessor activates the actuator to close the valve, thus increasing the particulate trap temperature; which in turn allows oxidation of the trapped debris.
It is an object of the present invention to provide a diesel engine particulate trap and regeneration system in order to reduce pollution.
It is another object of this invention to provide an improved system for controlling the regeneration cycle of the particulate trap. The resulting system will cause a minimum performance and efficiency loss to the engine and will be mechanized in a simple and reliable manner.
It is a further object of this invention to provide a regeneration system which is capable of raising the exhaust gas temperature to levels sufficient to cause incineration of the trapped particulate without the use of an auxiliary burner.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a turbocharged diesel engine and the exhaust gas particulate trap regeneration system of the present invention.
FIG. 2 is a schematic view of the engine and exhaust gas particulate trap regeneration system of FIG. 1 including a charge air cooler in the system.
FIGS. 3a and 3b are end and side cross-sectional views of the backpressure valve of the present invention.
FIG. 4 is a engine map of the loaded trap pressure vs. rack position at two engine speeds.
FIG. 5 is an engine map of engine back pressure vs. fuel input (rack position) for one engine speed and intake temperature.
FIG. 6 is an engine map of lines of constant backpressure required to obtain a 1200° F. trap inlet temperature plotted with fuel input and engine speed as coordinates.
FIG. 7 is an engine map of engine back pressure vs. engine air flow.
FIG. 8 is an engine map of air flow vs. fuel input.
FIG. 9 is an engine map of air/fuel ratio vs. fuel input.
FIG. 10 is an engine map of valve area vs. fuel input.
DETAILED DESCRIPTION OF THE INVENTION
An engine particulate trap system is shown in FIGS. 1 and 2 and generally comprises a combustion engine 12, such as a diesel powered internal combustion engine having a plurality of combustion cylinders, for rotatably driving an engine crank shaft. While shown to be used with a turbocharger 20, the particulate trap system of the present invention can be used with a naturally aspirated engine. The engine includes an air intake manifold 16 through which air is supplied by means of a compressor 18 of the turbocharger 20. In operation the turbocharger compressor 18 draws in ambient air through an air filter 22 and compresses the air with a rotatable compressor impeller to form so-called charge air for supply to the engine 12 via the inlet manifold 16 for combustion purposes.
Exhaust products are discharged from the engine 12 through an exhaust manifold 28 for supply to a turbine 24 of the turbocharger 20. The high temperature exhaust gas rotatably drives a turbine wheel (not shown) within the turbine housing at a relatively high rotational speed (up to 190,000 RPM) to correspondingly drive the compressor impeller within the compressor housing 18. In this regard, the turbine wheel and compressor impeller are carried for simultaneous rotation on a common shaft supported within the turbocharger center housing. After driving communication with the turbine wheel, the exhaust gases are discharged from the turbocharger 20 to an exhaust gas outlet 30 which includes the exhaust gas particulate trap 32 and noise abatement equipment. Located within the exhaust gas outlet 30 is a backpressure valve 34.
As shown in FIG. 1, the particulate trap regeneration system comprises the exhaust gas particulate trap 32, the backpressure valve 34 preferably located upstream of the particulate trap, an actuator 36 for electronically controlling the movement of the backpressure valve, and a microprocessor 38 for receiving relevant engine operating parameters and controlling movement of valve 34 via the actuator 36. Alternatively, the backpressure valve can be located upstream of the turbocharger 20 or downstream of the trap 32.
The exhaust gas particulate trap can be made of any suitable material or configuration capable of trapping and holding substantial quantities of particulates from the engine exhaust gas stream without creating an excessive restriction to the exhaust gas flow. It must also be able to withstand the elevated temperature required during incineration of the trapped particles. When used with a turbocharged engine, the particulate trap 32 should be located as close downstream of the turbocharger 20 as possible in order that the exhaust gas retain its high temperature. The trap 32 should have as low a pressure drop as possible in order to minimize the effect on engine performance.
Backpressure valve 34 can be any type of valve which provides control over the flow area; for example a butterfly valve. However, it has been found that it is important to provide accurate flow rates near shut off condition, therefore, a valve as shown in FIG. 3 is preferred. The valve 34 includes a casing 42 which converts the circular flow area of the inlet conduit into a generally rectangularly shaped cross-sectional flow area within the valve, see FIG. 3b. A valve head 44 having pivot pins 45 at each side is mounted within the casing 42. Pins 45 extend into bores in the casing 42 to pivotably support the valve head 44. One of the pins is connected to a suitable valve arm 46 which is connected to and pivoted by actuator 36. One edge 48 at the inlet and outlet of the valve is tapered in order to provide venier control near the shut-off point of the valve.
In addition to reducing exhaust emissions, the backpressure valve offers an additional important benefit; braking. As shown in FIG. 6, the combination of closing the back-pressure valve to increase back pressure and reduction of fuel flow makes the diesel engine an energy absorber rather than a energy producer. It is visualized that the backpressure valve will communicate with the vehicle control system to provide braking at various times. Of particular significance is use of the valve to brake on long steep grades without use of the vehicle friction brakes. Use of the back pressure valve for braking has three advantages: (1) Safety--it is a back up to the vehicle friction brake system; (2) Economy--it extends the life of the vehicle friction brake system; and (3) Utility--use of the back pressure valve for braking will automatically provide a degree of particulate trap regeneration.
Actuator 36 (FIGS. 1 and 2) can be of any suitable type; mechanical, electrical, pneumatic or any combination thereof. Actuators 36 receives a signal from the microprocessor 38 and converts it into the appropriate movement of valve arm 46 (FIG. 3) for proper positioning of the valve head 44.
As shown in FIG. 2, a charge air cooler 60 can be used in association with the turbocharged engine system of FIG. 1. When used, the charge air cooler 60 is located downstream of the compressior 18 and operates to reduce the temperature of the charge air in order to increase the density of the charge air supplied to the engine 12. A fan 62, run by a motor 63, can be located adjacent to the charge air cooler 60 for purposes of supplying cooling air through the charge air cooler. Located in parallel relationship to the charge air cooler is a charge air bypass conduit 64 having a charge air bypass valve 66 therein for controlling the amount of air flow to the charge air cooler 60.
Shown in FIGS. 1 and 2 are the controls which function to determine when the trap needs regeneration and then to maintain a nearly constant, high exhaust temperature over a wide range of engine speeds and loads during the time the trap is being regenerated. As shown, microprocessor 38 receives inputs from a selected number of inputs depending on the desired engine parameters used: a pressure sensor 68 located upstream of the backpressure valve 34, temperature sensors 70 and 72 located immediately upstream and downstream of trap 32, an air flow measurement device 74 located between the air filter 22 and the compressor 18, engine speed sensor 76, rack position or fuel flow sensor 78, oxygen sensor 82 in the exhaust manifold and signal 84 from a driver activated override lever. It it to be understood that a rack position sensor and a fuel flow sensor are interchangeable, however, a fuel flow sensor will provide a more desireable measurement.
The most likely method of determining when the trap needs regeneration is to sense pressure drop across the trap. When this pressure drop exceeds a value that represents a loaded trap pressure trop (see FIG. 4), the control will initiate the regeneration mode. The regeneration mode will then be continued until the particulates in the trap 32 are essentially all oxidized. Alternatively, continuing the regeneration mode for a certain time interval is an adequate and simple means for accomplishing this.
The pressure drop through the loaded trap will vary with engine load and speed. A map of the loaded trap pressure drop versus rack position or fuel flow and rpm will need to be developed for each engine and exhaust system. FIG. 4 is a typical map for a typical engine.
Each map can best be developed by running tests but can also be approximated by analytical means. The map will then be programmed into the memory of the microprocessor 38. Whenever the pressure drop exceeds the value on the stored map for a given load and speed, the regeneration mode will be triggered. In addition, the driver activated lever mounted near the vehicle steering wheel can send a signal 84 which can be used to close the valve 34 when braking is desired.
During the regeneration mode the control should modulate the back pressure valve 34 so that an essentially constant trap inlet temperature is maintained. This temperature should be approximately 1100° F. to 1200° F. for uncatalyzed traps and 750° F. to 850° F. for catalyzed traps. The most direct means for controlling exhaust temperature is to sense the exhaust temperature at 70; and to close the back pressure valve 34 incrimentally whenever the exhaust temperature is lower than the desired temperature and to open the valve whenever the temperature exceeds the desired temperature. Use of temperature as the controlling parameter requires careful dynamic matching of all system components to prevent valve overtravel and the attendent overshooting of the exhuast gas temperature which could damage the particlate trap and adversely effect engine emission and performance.
Care must also be taken to prevent exhaust gas over temperature during regeneration and following a sudden increase in fuel flow. The back pressure valve must open quickly when the engine fuel input is suddenly increased. The back pressure valve must open very quickly because the fuel input can increase from nearly zero input to maximum input within two revolutions of the engine. This quick response requires some means of anticipating the change in fuel input and/or a means of slowing the rate of increase in fuel. Hence, a rack position sensor 78 may be incorporated into the control system.
There are other less direct means for controlling exhaust temperature. For example, an engine map can be developed that will show what back pressure is needed to obtain the desired exhaust temperature for each combination of rack position or fuel flow, engine rpm and intake temperature. Using these parameters to control the back pressure and exhaust temperature is less direct than controlling temperature, but it would suffer less from response and overshoot problems. FIG. 5 is a typical map of backpressure vs fuel input (rack position) for one speed and intake temperature. FIG. 6 is an engine map of the backpressure required to obtain 1200° F. trap inlet temperature plotted as a function of fuel input and engine speed. Hence, for any given fuel flow and engine speed the microprocessor can signal the actuator to open or close the backpressure valve in order to obtain the desired backpressure.
A map of exhaust pressure required to obtain a desired exhaust temperature for each combination of engine air flow, rack position or fuel flow and intake temperature can be developed as shown in FIGS. 7 and 8.
Where the air/fuel ratio can be sensed accurately with an oxygen sensor 82 over a range from 18:1 to 80:1, this parameter could also be used along with engine speed and trap inlet temperature to signal the control system what back pressure is required to obtain a desired exhaust temperature. FIG. 8 shows a plot of air/fuel ratio vs air flow required to achieve various trap inlet temperatures.
The back pressure valve position might be used instead of back pressure to maintain the desired trap regeneration temperature providing the valve flow area can be accurately related to position for areas of 10.0 sq. in. down to approximately 0.2 sq. in. FIG. 10 shows valve flow area vs. fuel input.
Various modifications to the depicted and described system will be apparent to those skilled in the art. Accordingly, the foregoing detailed description of the preferred embodiment of the invention should be considered exemplary in nature, and not as limiting to the scope and spirit of the invention as set forth in the appended claims.
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A diesel engine exhaust particulate trap and regeneration system for trapping of particulates in the engine gases and periodic burning thereof is disclosed. Collected particulates are burned in the trap by increasing the trap temperature utilizing a backpressure valve in the exhaust gas line. A microprocessor, which receives engine operating parameters via sensors, compares the sensed parameter valves to engine maps stored in its memory and opens or closes the valve via an actuator in response thereto.
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TECHNICAL FIELD
[0001] The present invention relates generally to building construction products and more specifically to an elongated cap for a fence panel.
BACKGROUND OF THE INVENTION
[0002] Perimeter and accent fencing is extremely popular in residential home construction. Homes and apartments, as well as a variety of other buildings, often incorporate fencing into their design to create boundaries for foliage displays, pool and garden areas, and pet zones. Additionally, fences are commonly utilized to provide privacy and security by minimizing visual and physical unauthorized access.
[0003] Wood products traditionally have been the primary source of materials for use in fence and deck construction. However, wood products are becoming increasingly scarce due to the harvesting of trees at ever faster rates and the rather limited rate at which timber resources can be replenished. Also, environmental concerns and regulations directed to conservation or preservation of forests tend to restrict the availability of wood products. With the diminishing availability of timber resources, wood products are becoming increasingly expensive. There is, therefore, a substantial need for long-lasting substitute construction materials that can lessen the need to harvest timber resources.
[0004] One potential approach to addressing the above need is to provide substitute fence and decking products made of plastic, rather than wood. Plastic fence products provide a long-lasting alternative to wood. In addition, plastic fence products alleviate the need for costly painting and repainting. A variety of plastic building products are known. For example, U.S. Pat. No. 4,045,603 describes a three-layer synthetic construction material made from recycled waste thermoplastic synthetic resin material and cellulose fiber aggregate. This material includes face surfaces consisting essentially of re-hardened fused and rolled thermoplastic synthetic resin material bits, and an intervening core material consisting essentially of a compressed non-homogenous mixture of cellulose aggregate material bits and re-hardened fused thermoplastic synthetic resin material bits. Such plastic material can be used to create fencing elements.
[0005] Some of the essential elements of deck and fence construction are the railing and post members. The space or section between two posts, the panel, must be substantially solid when a fence is intended to provide privacy and security. Therefore, panel members need to provide an effective screen. The traditional fencepost and rail assembly incorporating spindle-type panel members is undesirable. However, a panel formed from a series of strategically placed boards provides an effective barrier.
[0006] Modular boards can easily be employed to construct such a panel, resulting in a long-lasting fence with all of the benefits described above for these substitute building materials. As a result of the manufacturing process, however, one feature of modular boards is a hollow interior. This affords a beneficially lightweight plank, but also creates an open end that requires covering. When modular boards are employed as cross-supports or railings, the open ends may be secured against a post. When utilized as planks in a vertical panel, a separate capping device is necessary. Known caps can be effective if planks are adequately spaced to allow for individual coverage and if the panels have a flat upper edge. However, where a more solid panel or an aesthetically arced panel is desired, such caps are disadvantageous. Furthermore, attachment of individual caps is time consuming and labor intensive.
[0007] A need yet remains in the art for an elongated cap that can adequately cover any fence panel regardless of board spacing or panel arc, that has an aesthetically pleasing appearance, and that can be installed quickly and easily. It is to the provision of such a cap that the present invention is primarily directed.
SUMMARY OF THE INVENTION
[0008] Briefly described, in a first preferred form the present invention both overcomes the above-mentioned disadvantages and meets the recognized need for such a device, by providing an elongated cap for a fence panel.
[0009] Generally, the present device is an elongated cap comprising a foam core surrounded by a durable casing. In a preferred form, the elongated cap is flexible to allow for adaptation to a variety of fence panel shapes. In a preferred form, the cap is aesthetically shaped and defines a substantially rectangular channel to allow the cap to be secured to the upper edge of a fence panel. Within the scope of the present device, it should be understood that the cap could define a different shape or style, depending on the shape of the corresponding panel members and the users preference. Preferably, channel walls are slightly angled toward each other to assist in effectively gripping corresponding boards, thus allowing the cap to remain secure along the fence panel.
[0010] An object of the present invention is to provide an elongated cap for a fence panel.
[0011] A further object is to provide an elongated cap which securely covers a fence panel, is strong and sturdy, and is weather-resistant.
[0012] Another object of the invention is to provide a flexible, elongated cap to fit a vertically or horizontally arcuate fence panel.
[0013] A further object of the invention is to provide an elongated cap that can be easily installed and removed.
[0014] Another object of the present invention is to provide a fence cap that does not require the use of screws/nails and that is aesthetically pleasing.
[0015] Still a further object of the invention is to provide an elongated cap having the strength to withstand external forces, yet remain flexible and lightweight.
[0016] These objects, advantages, and features of the present invention will become more apparent upon reading the following specification in conjunction with the accompanying drawing figures.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
[0017] The present invention will be better understood by reading the Detailed Description of the Preferred Embodiment with reference to the accompanying drawing figures, in which:
[0018] [0018]FIG. 1 is a cross-sectional view of the elongated cap according to a preferred form of the invention, where the cap is shown positioned on a board A.
[0019] [0019]FIG. 2 is a perspective view of the elongated cap of FIG. 1, where the cap is shown secured on a substantially flat fence panel.
[0020] [0020]FIG. 3 is a perspective view of the elongated cap of FIG. 1, where the cap is shown secured on a substantially arcuate fence panel.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] In describing the preferred and alternate embodiments of the present invention, specific terminology is employed for the sake of clarity. The invention, however, is not intended to be limited to the specific terminology so selected.
[0022] Referring now in detail to the drawing figures, wherein like reference numerals represent like parts throughout the several views, FIGS. 1 - 3 show an elongated cap 10 according to a preferred form of the invention. The cap 10 preferably comprises a casing 20 , a channel 30 and a foam core 40 .
[0023] In the preferred form, the elongated cap 10 is a one-piece modular extrusion wherein the casing 20 is molded plastic surrounding a foam core 40 . However, one skilled in the art will recognize that alternative materials may be used such as, for exemplary purposes only, rubber or glass fiber. Preferably, the casing 20 is formed by a peripheral wall 22 defining an interior cavity 24 . The peripheral wall 22 generally has a top exterior wall 26 , two side exterior walls 28 a and 28 b , and channel walls 30 a , 30 b and 30 c . In the preferred form, the peripheral wall 22 is preferably of sufficient density and thickness to provide strength and durability yet remain lightweight and flexible. Although the thickness of the peripheral wall 22 may vary, the preferred thickness is 0.010 to 0.100 inches. The casing 20 surrounds the foam core 40 , shaping the three-dimensional cap 10 into the desired cross-sectional design.
[0024] The channel 30 has an upper wall 30 c and two side walls 30 a and 30 b thereby defining corners 36 a and 36 b . The channel 30 is substantially rectangular shaped and dimensioned to snugly receive a plurality of boards A. Preferably, the upper wall 32 is substantially flat to buttress the end of the boards A. To further secure the boards A within the channel 30 , sidewalls 30 a and 30 b preferably extend from upper wall 30 c at an angle slightly less than ninety degrees. As such, when the boards A are slid into the channel 30 , the sidewalls 30 a and 30 b are urged inward onto the board A thereby acting as a claw or clamp to secure cap 10 thereto.
[0025] The foam core 40 fills the interior cavity 24 of the elongated cap 10 thereby providing lightweight and flexible support for the peripheral wall 22 . The foam core 40 is preferably formed from 0.6 density foam, thus resulting in a formable yet flexible core. The flexibility of the foam core 40 allows the elongated cap 10 to be adapted to fit a variety of fence panel shapes.
[0026] In use, the elongated cap 10 is preferably positioned with the upper wall 30 c of the channel 30 substantially flush with an upright board A. The channel 30 , however, may be formed with a sufficient depth to allow for secure positioning of the elongated cap 10 without the upper wall 30 c being substantially flush with an upright board A. The pre-formed length of elongated cap 10 is preferably trimmed to fit between two upright fence posts, as desired. As best seen in FIG. 2, the elongated cap 10 may be utilized substantially along a straight line wherein the boards A of a fence panel are substantially coplanar and wherein the ends of the boards A are substantially parallel. The elongated cap 10 may also be utilized at a fixed or variable angle wherein the boards of a fence panel may be of substantially equivalent length, but advance on a slope. As best seen in FIG. 3, the elongated cap 10 may be utilized on a substantially arcuate fence wherein the boards A of a fence panel are not coplanar. Elongated cap 10 can also be utilized to cover boards that were either manufactured or cut with slight imperfections to provide a level decorative covering.
[0027] In an alternative form, adhesive may be utilized within the channel 30 to provide a more permanent method of securing the elongated cap 10 to a fence panel.
[0028] In an alternative form, the elongated cap 10 could be formed with a plurality of fastening apertures to allow a screw, bolt, nail, or other fastening device to extend through at least one of the two side exterior walls 28 a and 28 b , and through at least one of the respective side walls 30 a and 30 b of channel 30 , and attach to the board A.
[0029] Although a preferred shape of elongated cap 10 is shown in the figures, it is contemplated that the elongated cap 10 could be of varied shapes to complement a variety of fence styles and user preferences.
[0030] Having thus described the preferred and alternative forms of the present invention, those skilled in the art will readily recognize that the within disclosure is exemplary only, and that various other alternatives, adaptations, and modifications may be made therein within the spirit and scope of the present invention as set forth in the following claims.
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A flexible elongated cap for topping a fence panel. The elongated cap comprises a durable casing surrounding a foam core wherein the casing defines a channel for receiving the upper end of the fence panel. The side walls of the channel are angled inward to provide a clamping affect over the upper end of the fence panel. The cap is aesthetically shaped and is flexible to allow for adaptation to a variety of fence panel shapes.
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BACKGROUND OF THE INVENTION
(a) Field of the Invention
The present invention refers to a new composition based on a natural, artificial and/or synthetic polymer, having self-extinguishing properties. In the description of the present invention, "synthetic polymer" means in particular a polyamide, a copolyamide, a polyester, or a copolyester; "artificial polymer" means in particular regenerated cellulose materials; and "natural polymer" means in particular cotton.
The present invention further refers to a process for rendering a composition based on said polymer or polymers, self-extinguishing, by adding a particular self-extinguishing additive, which will be better specified hereinafter, to the polymer itself, or, in the case of synthetic polymers, said additive may be added during the polymerization or before their transformation into formed materials. Further objects of the present invention will be indicated hereinafter.
(b) The prior art
It has been known for many years that the polymers of natural, artificial or synthetic origin constitute a danger because of their inflammability. This danger is particularly intensified in the case of textile materials, which contribute to a high percentage of accidents due to ignition of wearing apparel or textile products for furniture. The textile materials in regard to which the inflammability problem is particularly felt, are those derived from cellulosic fibres (rayon and/or cotton), synthetic fibres (such as polyamide, polyester) and also mixtures of cellulosic with synthetic fibres.
In general, in order to render a product self-extinguishing there exist mainly the following techniques:
(1) to use in the polymerization comonomers having self-extinguishing properties; and/or
(2) to add substances having self-extinguishing properties to the polymers by means of extrusion operations in an extruder; and/or
(3) to apply finishes containing self-extinguishing substances onto articles, e.g. fabrics, films, curtains, etc.
In order that one of methods (1) or (2) may be successful, it is necessary that the self-extinguishing agents employed should not produce or promote degradation reactions or other harmful reactions during the polymerization or whenever they are added. For instance, in the case of the polyamides, some types of products which impart self-extinguishing properties and which are used successfully for other classes of polymers, such as polyethyleneterephthalate, have proved to be unsuitable. Among these may be cited the halogenated compounds, in particular organic brominated or chlorinated compounds, which in the case of the polyamides cause a strong degradation of the polymer without significantly delaying the propagation of the flame.
Also certain phosphorated additives, which are notoriously self-extinguishing, especially in the presence of nitrogen containing substances, exert their self-extinguishing activity on the polyamides only when they are added in such high amounts as to affect negatively the peculiar characteristics of the polymer, such as spinnability, mechanical properties, color, etc.
Finally, certain substances containing nitrogen and sulphur, such as thiourea, ammonium sulphamate, thiocyanates, are not adapted for the polyamides when employed as comonomers or added by mixing them with the polymer in the molten state since they promote viscosity degradation and colour alteration of the polymer. For this reason such products or the polymers derived therefrom (urea, thiourea with formaldehyde and/or with melamine) are employed as self-extinguishing components only according to method (3), for polyamidic textile articles. Melamine, which confers to the polyamide a certain degree of flame retardant properties, has the disadvantage that it is not soluble in polycapronamide even at a concentration of 0.5%. Actually, the requirement of the homogeneity of the flame retardant agent in the polymer is fundamental, if the polymer is intended to be used as a fibre.
Therefore it is natural that when method (1) or (2) cannot be used to impart properties of resistance to the flame, it becomes necessary to resort to method (3), which consists in the application of self-extinguishing finishes. Such method further is the only one available for imparting self-extinguishing properties to certain products of cellulosic origin, such as cotton products.
It is also known that mixtures of fibres of cellulosic origin with thermoplastic fibres (polyester, polyamide fibers), are not self-extinguishing even if one fibre component has been treated with a self-extinguishing additive. Therefore for such mixtures it is advantageous to effect finishing treatments with additives that are effective to impart self-extinguishing properties both to the cellulose and to the thermoplastic fibre. In these cases however, the choice of the additive or additives is a difficult one because their activity, understood as the capability to impart self-extinguishing properties, is not the same for different materials.
A suitable solution for rendering a synthetic polymer (based on a polyamide or a polyester) self-extinguishing, when it is desired to employ self-extinguishing additives to be added to the molten polymer, consists in finding substances that will not cause undesirable thermodegradation of the polymer and will not negatively interfere with its colour and/or its physico-chemical and mechanical characteristics. Because of the many negative factors hereinbefore mentioned, the production of flame retarded or self-extinguishing polymers of the classes mentioned (polyamides and/or polyesters) by the addition of self-extinguishing compounds to the molten polymer and/or by copolymerization with self-extinguishing monomers, has remained a problem to the present time.
SUMMARY OF THE INVENTION
The Applicants have now surprisingly found an additive which is particularly effective with regard to the combustion of said polymers; this product does not give rise to thermodegradative reactions and/or to irreversible alterations of the polymer to which it is added either during addition in an extruder or during thermoforming or even during polymerization (in the case of synthetic polymers). Said additive includes one or more products derived from the transformation of melamine, preferably in the presence of water, in an acid medium: said acidity may be provided by inorganic acids and/or anhydrides or by organic acids and/or corresponding anydrides or even by mixtures of organic and/or inorganic compounds of an acid character.
One object of the present invention is, therefore, to provide compositions based on a synthetic polymer, in particular a polyamide, a copolyamide, a polyester, or a copolyester, an artificial polymer in particular regenerated cellulose materials, or a natural polymer such as cotton, having self-extinguishing properties, characterized by the fact that they contain as a self-extinguishing additive, one or more products (A) derived from the transformation of melamine, preferably in the presence of water, and of at least a compound having an acid character chosen from the group consisting of an organic acid, an anhydride of an organic acid and an inorganic acid, wherein in the case that polyamide are treated, said product (A) may be further modified with caprolactam.
It is also to be understood that it is possible to employ as an acid medium, according to the invention, a mixture comprising one or more organic acids and/or inorganic acids in the presence or in the absence of one or more organic anhydrides, any combination between organic acids, inorganic acids and/or organic anhydrides being possible.
As an organic acid, formic, acetic or butyric acid is preferably employed; as anhydride of an organic acid, acetic, propionic, butyric or phthalic anhydride is preferably employed; and as an inorganic acid, sulphuric or phosphoric acid is preferably employed.
Product (A) may be added, in the case of synthetic polymers, for instance:
(1) by addition during the polymerization to monomers which form polyamides and/or copolyamides, polyesters and/or copolyesters;
(2) by addition in an extruder during the extrusion operation; the granules containing the additive may be used to obtain moulded bodies or may be used for melt spinning in order to obtain fibres and therefore textile manufacts which are self-extinguishing;
(3) by application of finishes essentially comprising an aqueous suspension and containing a binder capable of binding product (A) onto the fabric under heating.
In the case of regenerated cellulose materials, such as rayon, product (A) may be directly added to the viscose and subsequently precipitated in the coagulating bath (whereby product (A) remains incorporated in the cellulosic material) or may be applied by a finishing operation to the cellulosic fabric, analogously to what has been described for synthetic polymers under (3).
Further, in the case of fabrics comprising polyester/cotton mixtures, with different cotton percentages, or in the case of cotton alone, said fabrics may be rendered self-extinguishing with a suitable finishing operation as previously described under (3) for synthetic polymers.
Product (A) is preferably present in the polymeric composition in amounts from 0.5% to 30% inclusive, more preferably from 2% to 15% inclusive; said percentages being by weight with respect to the weight of the polymer.
In the preparation of the self-extinguishing additive (product A), the molar ratio of melamine to anhydride and/or to acid may vary widely; at any rate, it is preferred to operate with ratios from 4 to 0.1, preferably from 2 to 0.5.
According to the present invention, the transformation of the melamine in an aqueous-acid medium may occur under conditions known in the art for this type of reaction. The temperature may vary from 100° to more than 300° C., provided that the reaction vessel is capable of withstanding the autogenous pressure. Preferably, in order to take advantage of an appreciable reaction speed, the temperature should be above a lower limit of at least 130° C., or preferably between 150° C. and 180° C.
The product (A), which has self-extinguishing properties, obtained by the present invention, is constituted by carbon, hydrogen, nitrogen and oxygen. In particular, the carbon content is comprised in the range 25-60%, the nitrogen content is comprised between 3% and 60%, the rest being hydrogen and oxygen, the carbon content being more often 25-33%.
Additive (A) is a product which has shown a considerable versatility, inasmuch as it is effective both for synthetic polymeric materials, in particular those having amidic functional groups (e.g. polycaprolactam and hexamethylenediamine polyadipate), and for cellulosic materials (cotton and rayon) and/or textile mixtures rayon-polyester or cotton-polyester. Sometimes the additives of the art, which impart self-extinguishing properties to cellulosic fabrics, are not equally effective for the materials obtained from synthetic fibres or the additive itself has such a chemical structure and thermal stability that it must be employed only in finishes.
On the contrary, the additive of the present invention is possessed of other advantages, besides that of imparting self-extinguishing properties. In particular said additive exhibits the following properties:
(a) it is only slightly soluble in hot water (solubility less than 1 gr/lt), whereby the articles containing product (A) can maintain their self-extinguishing properties even after contact with water;
(b) it has very high melting and/or degradation temperatures (above 300° C.) and therefore it is possessed of a considerable thermal stability under the normal conditions of extrusion, moulding, polymerization, spinning of the materials for which it is intended;
(c) it disperses homogeneously in the polyamides up to substantial concentrations, e.g. greater than 10% by weight with respect to the polyamide.
A further object of the present invention is to provide a process for the preparation of the compositions based on synthetic, artificial or natural polymers, having self-extinguishing properties. Said process is characterized in that product (A) is added in an amount from 0.5% to 30%, preferably from 2% to 15%, inclusive (by weight), to the polymer, or, in the polymerization stage, to the monomers from which the polymer derives. More particularly said product (A) may, for instance, be added to and mixed with the polymer in an extruder in the extrusion operation or by application of a finish essentially constituted by an aqueous suspension and containing a binder capable of binding the product (A) onto the fabric by heat, or even may be added to the melt under stirring during the polymerization of the monomer or monomers which form the synthetic polymers such as polyamides, copolyamides, polyesters and copolyesters.
The self-extinguishing polymeric compositions which are an object of the present invention, are particularly adapted for uses as textile fibres (including non-woven fabrics), films, and articles extruded or formed in any way. Such fibres, films, articles, and the like containing the additive (product A) according to the invention, are also an object of the present invention.
Other compounds which may be optionally added together with product (A), are products which are known to be effective against thermo-oxidative degradations and are therefore effective in maintaining the white colour of the polymers, in particular in the case of polyamides. A chain extender, such as diphenylcarbonate, may also be added in amounts up to 0.5% by weight with respect to the polyamide; this product is effective against any possible decrease in the viscosity due to the flame retardant component, when this is added in substantial amounts, e.g. more than 10% by weight with respect to the polyamide.
The tests which have been carried out to determine the effectiveness of product (A) in imparting self-extinguishing properties, according to the invention, are known by the denominations: DOC FF 3-71 (standard for night pajamas for children, size 0-6); limiting oxygen index (L.O.I.) which indicates the minimum oxygen concentration necessary for combustion; U.L. (Underwriter's Laboratory) bulletin 94; ISO-TC 92 DOC 382 of the "Radiant Panel" (generally employed for wall coverings, ceilings, flooring, carpets). Finally, an empirical but highly significant test which permits evaluating the degree of the self-extinguishing properties on small amounts of thermoplastic polymer (e.g. polyamides), consists in determining the number of ignitions required for the complete combustion of a twine constituted by a pluraity of monofilaments of a given length, as will be described in the following examples.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The following examples illustrate but do not limit the present invention. Examples 1,2,17,19 and 20, refer to the preparation of a product (A) according to the invention, while the remaining examples refer to the preparation of the compositions based on the self-extinguishing polymeric compositions and to the inflammability tests relative thereto.
All the parts are by weight unless otherwise stated.
EXAMPLE 1
Preparation of a self-extinguishing product (A), obtained by the reaction in an aqueous medium of melamine and acetic anhydride in equimolecular amounts
189.2 parts of melamine and 153.1 parts of acetic anhydride are suspended in 1500 parts of water in a suitable reactor provided with a stirrer; the suspension is heated to 175° C. in a nitrogen atmosphere. The heating is continued for 20 hours at the said temperature; the pressure rises to 8-9 atmospheres. The product is filtered and is washed twice with 2000 parts of water heated to 90° C., whereby 113 parts of a white product (A) are obtained.
On the product (A) thus obtained, the following determinations are carried out:
Melting Point, above 320° C.;
Solubility in water 0.4 gr/lt at 20° C.;
Elemental analysis: C=27.4%, H=3.5%, N=49.1%;
Equivalent weight determined by titration with sodium hydroxide 156.5;
Equivalent weight determined by titration with perchloric acid in acetic acid 132.2.
The infrared spectrum shows main absorptions at 3470 cm -1 , 2720-2690 cm -1 , 1720 cm -1 , 1630 cm -1 , 1515 cm -1 , 1190 cm -1 , 980 cm -1 , 785 cm -1 , 540 cm -1 , 440 cm -1 .
EXAMPLE 2
Preparation of a modified self-extinguishing product (A), obtained by the reaction in an aqueous medium of melamine and acetic anhydride in equimolecular amounts in the presence of caprolactam
189.2 parts of melamine, 153.1 parts of acetic anhydride, 12.73 parts of caprolactam and 1500 parts of water are added to one another in the reactor used in Example 1.
The operations are carried out in the same way as in the preceding Example. 117 parts of modified product (A) are obtained after washing.
The following determinations are carried out on the modified product (A):
Melting Point, above 320° C.;
Solubility in water, 0.28 gr/lt at 20° C.;
Elemental analysis: C=28.3%, H=3.5%, N=49.0%;
Equivalent weight determined with sodium hyroxide, 123.3;
Equivalent weight determined by titration with perchloric acid in acetic acid, 133.9.
The infrared spectrum shows main absorptions at 3460 cm -1 , 2720-2690 cm -1 , 1730 cm -1 , 1660 cm -1 , 1440 cm -1 , 1190 cm -1 , 980 cm -1 , 790 cm -1 , 540 cm -1 , 440 cm -1 .
EXAMPLE 3
Moulding of self-extinguishing polyamide-6 (polycapronamide) and inflammability test relative thereto
6 parts of product (A) modified, obtained according to Example 2, were mixed and extruded in a Creusot-Loire extruder with 94 parts of polyamide-6 (relative viscosity 2.67, measured at 20° C. at a concentration of 1 gr/100 cm 3 of 96% sulphuric acid) at 255° C. The polymer containing the additive was moulded in a Negri and Bossi extruding machine (type V 7-9 F.A.) under the following conditions: pressure 100 Kg/cm 2 , duration of the injection 2 seconds, temperature of the moulds 20° C.; the pieces obtained from the moulding are subjected to test U.L. 94.
The pieces with thicknesses 1/4, 1/8, and 1/16 of an inch are classed in class SE-O. Such a classification means that the pieces are self-extinguishing and do not dribble.
EXAMPLE 4
Preparation and spinning-stretching of a composition based on self-extinguishing polyamide-6 (polycapronamide) and inflammability test relative thereto
6.3 parts of modified product (A) (obtained according to Example 2) and 93.6 parts of granules of polyamide-6 (relative viscosity 2.67, measured as in the preceding Example) were extruded in a Creusot-Loire extruder. The temperature of the extruder head is 245° C.
The polymer containing the additive (relative viscosity 2.56) is spun to a count of 40/10 den. under the following conditions:
spinneret temperature: 265° C.;
draw ratio: 3.08.
The fibre has a tenacity of 3.4 gr/den and an elongation of 31.6%. A twine 50 cm long, composed of 300 monofilaments, has been obtained from said yarn; this is subjected to an empirical but significant test to evaluate the self-extinguishing effect. The test consists in determining the number of ignitions necessary for the complete combustion of the twine.
An average of 23 ignitions is required for the sample containing the self-extinguishing additive, whereas an identical twine made from polyamide-6 without any additive requires an average of 4 ignitions to burn completely.
EXAMPLE 5
Spinning and bulking of the self-extinguishing polyamide-6 (polycapronamide) yarn and inflammability test carried out on a carpet made from said yarn
7.1 parts of product (A) obtained according to Example 1 and 92.9 parts of polyamide-6 (relative viscosity 2.67) were extruded in a Creusot-Loire extruder.
The polymer containing the additive, thus obtained, (relative viscosity 2.52), is continuously spun to a count of 15 denier per filament (the temperature of the head is 257° C.). The yarn is then stretched and bulked; then a "loop" type carpet is made from said yarn on a primary foundation of polypropylene non-woven fabric.
The sample carpet is subjected to the test ISO-TC 92 DOC 382, in which it is classed in class 1.
A similar carpet, which however has been obtained using normal polyamide-6, is classified in class 2 according to the same test, viz. its behaviour to the flame is inferior.
EXAMPLE 6
Preparation of a self-extinguishing composition based on polyamide-6,6 (hexamethylenediamine polyadipate) and inflammability test relative thereto
8 parts of modified self-extinguishing product (A) (obtained according to Example 2) and 92 parts of polyamide-6,6 (relative viscosity 2.70) are melted at 290° C. under a nitrogen stream in a glass container provided with a stirrer.
The polymer containing the additive was spun and a 50 cm long twine was prepared from 7 monofilaments.
The test consists in determining the number of ignitions necessary for the complete combustion of the twine. The aforesaid twine required on the average 21 ignitions, whereas a similar twine made from polyamide-6,6 without the additive has required 2 ignitions on the average to burn completely.
EXAMPLES 7-8
Treatment of a cellulosic fabric with a self-extinguishing composition containing the product (A) obtained according to Example 1
19.5 parts of said product (A), finely comminuted (particle size: 1-5 microns) was suspended in a solution containing 6.5 parts of trimethylolmelamine (TMM), 1.6 parts of polyethylene glycol having molecular weight 800 (PEG-800), 0.065 parts of zinc chloride and 0.015 parts of an emulsifier in 72 parts of water acidified to pH 2.5 with phosphoric acid.
A fabric of cellulosic fibre sold under the trademark "Koplon" of the Snia Viscosa Company, having a weight of 130 gr/m 2 , was treated by immersion into the suspension having the aforesaid composition.
After drying, a weight increase of 25.7% was noted. The oxygen index (L.O.I.) of the product thus treated is 29.2% whereas a sample of the same cellulosic fabric treated with the same finishing composition not containing however the product (A) exhibited an oxygen index of 19%.
A second sample of "Koplon" fabric treated in the same way and with the same finishing suspension containing product (A), is kept in an air oven at 160° C. for 4 minutes. After drying to constant weight, the weight increase was found to be 30.6%; the oxygen index (L.O.I.) is 31.9%.
EXAMPLES 9-10
Treatment of cellulosic fabrics with a self-extinguishing composition, followed by exposure to an ammonia stream
A sample of a fabric of "Koplon" (Snia Viscosa) cellulosic fibre is treated in the same way as described in Example 7 and with the same self-extinguishing finishing composition in aqueous suspension, indicated in Example 7.
After said treatment, the sample, placed in a suitable vessel, is homogeneously contacted by a stream of ammonia gas at 70° C. for 60 minutes. After degasifying, the fabric is dried in an oven for 12 hours at 105° C. under a partial vacuum. The weight increase has been calculated to be 31%, the oxygen index (L.O.I.) is 32%.
The same fabric sample treated for 45 minutes with water at 60° C. and with an aqueous solution of sodium bicarbonate at 0.5%, loses 6% of the additive. Therefore the increase in self-extinguishing composition with respect to the initial weight has been 26%; the corresponding oxygen index is 27%.
The Example just described is repeated on a cotton fabric (weight 91 gr/m 2 ); the weight increase was 23% and the oxygen index (L.O.I.) 28.1%. The same fabric of untreated cotton has an L.O.I. of 18.5%.
EXAMPLES 11-12
Treatment of cellulosic fabrics with a self-extinguishing finishing composition containing, besides product (A), also a phosphorus derivative (V)
The self-extinguishing composition comprises 13.8 parts of product (A) of Example 1, 4.6 parts of TMM (trimethylolmelamine), 7.9 parts of sodium polyphosphate, 1.2 parts of PEG-800, 0.05 parts of zinc chloride and 0.011 parts of emulsifier in 72 parts of water. A sample of "Koplon" fabric treated with the said composition, after being kept at 160° C. for 4 minutes and after successive drying at 105° C. under a partial vacuum, shows a weight increase of 28.3%; the oxygen index (L.O.I.) is 35%. Five test samples derived from said fabric sample pass the standard set by DOC FF 3-71. A sample of the same fabric analogously treated with the same finishing composition except that it does not contain product (A), has an oxygen index of 21%. Test pieces derived from this sample do not pass the standard set by DOC FF 3-71.
Similarly, a cotton sample, also treated with the said self-extinguishing composition containing product (A), shows a weight increase of 31% and the oxygen index is 32.7%. In this case too the standard set by test DOC FF 3-71 is passed.
EXAMPLES 13-14
Treatment of polyester fabric, also mixed with cellulosic fibre, with self-extinguishing composition
A fabric made from polyester fibre is treated with the same self-extinguishing composition and in the same way as indicated in Example 7.
After drying, the weight increase was 26.8% and the oxygen index is 29.7%. A sample of the same fabric treated with the same finishing composition except that it does not contain the product (A) had an oxygen index of 23%.
A fabric obtained from a mixture comprising 65 parts of polyester fibre and 35 parts of "Koplon", was subjected to the same treatment with the self-extinguishing composition containing product (A), indicated in Example 7. After drying, the weight increase was 29.8%; the oxygen index was 31.1%.
A sample of the same fabric treated with the same composition except that it does not contain product (A), has an oxygen index of 22%.
EXAMPLES 15 and 16
Product (A) synthesized from melamine in the presence of organic acid (butyric anhydride and acetic acid)
The operations are carried out as in Example 1, in the presence of 168.2 parts of melamine, 40 parts of acetic acid, and 106 parts of butyric anhydride in 1000 parts of water.
The product (A) is found to be identical as to its characteristics, to those previously analyzed, as to melting point, solubility in water, titration with perchloric acid, and infrared absorption spectrum.
A twine prepared from yarn containing the aforesaid product (A) as additive, exhibits an identical behaviour as to combustion: 17 ignitions are required.
EXAMPLES 17 and 18
Product (A) synthesized from melamine in the presence of propionic anhydride
The operations are carried out as in Example 1, using 168.2 parts of melamine, 175 parts of propionic anhydride, and 1000 parts of water.
The product (A) thus obtained has identical characteristics to those previously analyzed, as to its melting point, solubility in water, titration with perchloric acid and infrared absorption spectra.
A twine prepared from yarn containing the aforesaid product (A) as additive, exhibits an identical behaviour as to its combustion: 17 ignitions are required.
EXAMPLE 19
Preparation of a product (A) by reaction between melamine and phthalic anhydride in molar ratio 2:1 in an aqueous medium
189.1 gr of melamine (1.5 mols), 111.1 gr of phthalic anhydride (0.75 mols) and, subsequently, 1300 cm 3 of water are loaded into a 2 lt autoclave provided with a stirrer. The autoclave is closed and is heated up to 160° C. in an oxygen free nitrogen atmosphere. The heating is continued for 20 hours at the said temperature, under stirring; the autogenous pressure rises to 6-7 atmospheres. The suspension obtained is cooled to room temperature and is filtered, separating the solid part from the mother liquors. The solid is repeatedly washed with water heated to 80°-90° C.; the residue of said washings is 104 gr (product A). From the concentrated wash waters 42.1 gr of phthalic acid are obtained.
The said product (A) has the following characteristics:
Melting point above 320° C.;
Elemental analysis: C=38.3%, H=3.8%, N=52.2%;
Equivalent weight determined by titration with KOH, 316.
The infrared spectrum shows main absorptions at 3350 cm -1 , 2700-2100 cm -1 , 1730 cm -1 , 1440 cm -1 , 1190 cm -1 , 790 cm -1 , 550 cm -1 .
EXAMPLE 20
Preparation of a product (A) by reaction between melamine and phthalic anhydride in molar ratio 1:1 in an aqueous medium
(a) 252.3 gr of melamine (2 mols), 296.2 gr of phthalic anhydride (2 mols) with 1500 cm 3 of water are loaded into the apparatus described in Example 19. The same operations as described in Example 19 are carried out. The reaction is continued for 18 hours at 160° C. After cooling, the solid is separated from the water; the residue is washed repeatedly with hot water and extracted with methyl alcohol under reflux.
The residue of the extractions (product A) is in the amount of 369.6 gr. After uniting the mother liquors with the wash waters, 155.2 gr of phthalic acid and 124.4 gr of phthalic anhydride are recovered by concentration.
The said product (A) has the following characteristics:
Melting point above 320° C.
Solubility in water at 100° C., 0.07%;
Elemental analysis: C=41.1%, H=4.0%, N=44.7%;
Equivalent weight determined by titration with KOH, 214.
The infrared spectrum shows main absorptions at 3350 cm -1 , 2700-2100 cm -1 , 1730 cm -1 , 1440 cm -1 , 1190 cm -1 , 990 cm -1 , 780 cm -1 , 630-660 cm -1 , 540 cm -1 .
(b) When the reaction between melamine and phthalic anhydride in equimolecular ratio was prolonged for 30 hours at 160° C., 368.4 gr of product (A) were obtained after extraction with hot water and 194.8 gr of phthalic acid are recovered.
This product (A) has a melting point above 320° C., equivalent weight 215, and the following elemental analysis: C=42.0%, H=4.5%, N=46.5%.
EXAMPLE 21
Preparation and spinning of self-extinguishing polyamide-6 (polycapronamide) and inflammability test relative thereto
12.15 Kg of polyamide-6 chips (relative viscosity 3.2, measured in 96% sulphuric acid at a concentration of 1% and at 20° C.) together with 780 gr of a mixtures of products (A) obtained according to Examples (20a) and (20b), in equal parts by weight (6.4% by weight with respect to the polyamide-6), 39 gr of diphenylcarbonate and 13 gr of titanium dioxide are extruded in a Creusot-Loire extruder. The temperature of the extruder head is 245° C.
1 Kg. of polyamide-6 chips containing the self-extinguishing additive, thus prepared, is spun to a count 40/10 (40 den, 10 filaments) under the following conditions:
Temperature of the spinning heads 231° C.;
Take-up speed 680 mt/min;
Draw ratio 3.52;
Temperature of the first cylinder 85° C.
The fibre thus obtained has a tenacity of 2.86 gr/den, and an elongation of 378%. The relative viscosity of the yarn, measured as hereinbefore described, is 2.0. Fifteen samples of stockings obtained from said yarn (weight 100 gr/m 2 ) were subjected to the test DOC FF 3-71. All of the samples passed the required standard (on each test, three glass filaments are interwoven). Under the same conditions, the same polyamide without the additive did not pass the test.
EXAMPLE 22
Preparation of a moulding mass from self-extinguishing polyamide-6 (polycapronamide) and inflammability test relative thereto
1 Kg of polyamide-6 chips containing 3.2% of flame-retardant product (A) as described in Example 19, are moulded in an extruding machine Negri and Bossi (type V 7-9 F.A.) under the following conditions: pressure about 100 Kg/cm 2 ; duration of the injection 1 second, temperature of the moulds 80° C.
Samples having thickness of 1/4, 1/8, and 1/16 of an inch, five for each thickness, are subjected to the U.L. test. The combustion lengths are 0.8, 0.7 and 0.2 cm respectively for the three thicknesses. All the samples are classed in class SE-O.
EXAMPLE 23
Preparation of a self-extinguishing composition based on polyamide-6,6 (hexamethylenediamine polyadipate) and inflammability test relative thereto
48.5 gr of polyamide-6,6 (relative viscosity 2.65) are melted together with 1.5 gr (3.1%) of the product (A) obtained according to Example 19, at 290° C. in a glass container provided with a stirrer, under nitrogen stream (O 2 less than 10 ppm). After complete melting, the mass is stirred in a nitrogen stream for 10 minutes.
The polymer containing the additive has a relative viscosity of 2.1. A twine of 7 monofilaments obtained from this product required 22 ignitions to burn completely whereas a comparable twine from the same polyamide but not containing the additive, required only 2 ignitions.
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A new composition is described comprising a synthetic, artificial or natu polymer and a flameproofing additive imparting self-extinguishing properties to the composition and to the articles, such as moulded, spun or woven articles, made therefrom, said additive being the product of the reaction of melamine with acidic compounds, such as organic acids or anhydrides and inorganic acids. The process for making said additive by said reaction, preferably in the presence of water, is also described. The said composition may be made by introducing said additive in any manufacturing stage, viz. to the monomers (if the polymer is a synthetic one), to the molten polymer, to polymer solutions such as viscose dope, to polymer chips during extrusion, or to finished products e.g. by applying a finish to fabrics.
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This application is a continuation of Application Ser. No. 126,390, filed Nov. 30, 1987, now abandoned.
FIELD OF THE INVENTION
This invention relates to negative air pressure asbestos removal, and in particular relates to negative pressure asbestos removal provided with localized make-up air.
BACKGROUND OF THE INVENTION
The removal of asbestos materials from buildings has evolved into a procedure with fairly standard practices and environmental controls. These have been reinforced by recent State and Federal (OSHA) regulations controlling the construction and renovation industry which now mandate practices of isolation, HEPA (high efficiency particular air) air filtration, and establishing a negative pressure enclosure. Prior art, such as the patent to Natale, U.S. Pat. No. 4,604,111, also teaches the use of negative pressure in the removal of asbestos.
A typical asbestos removal site is prepared by sealing all penetrations into the work area and covering floors, walls, and horizontal surfaces with plastic sheeting. An artificial "bubble" is thus created into which there is only one entrance which serves both as the worker's access and decontamination facility. Fans with highly efficiency HEPA filters are situated within the work area to exhaust air from within the enclosure to the surroundings. Make-up air is provided through the worker's access/decontamination unit, and the constant exhausting of large volumes of filtered air from within the work area relative to the much smaller amounts of make-up air admitted through the decontamination unit creates a negative static pressure relative to the surrounding spaces. The dual features of these ventilation units, namely--the production of a negative static pressure within the enclosure and the air filtration capability of the HEPA filters, has caused an unclear perception with regard to the actual purpose and applicability of this widespread engineering technique. This standard feature of asbestos work zones is presently not clearly defined from the perspective of industrial hygiene ventilation and retains features of an industrial hygiene as well as an environmental control. Consideration of the "negative air" concept as industrial hygiene ventilation allows a more clear description of its capabilities and limitations, as well as enabling alternatives from current practice in controlling airborne asbestos.
The basic concept and empirical derivations of industrial hygiene ventilation that are standard today have evolved over the last forty or fifty years. The variety of aerosols and vapors to be controlled in classical industrial hygiene settings have generally been incidental to the formuation of some desired material, and engineering solutions to these airborne hazards have taken two approaches. General dilution ventilation (the first approach) as been most applicable where the generation of a relatively low hazard contaminant evolves from such a widespread area that point control by local exhaust at the source is impractical. An example of this would be the general ventilation necessary to maintain an office environment free of excessive cigarette smoke.
The object of the general dilution type of control method is to bring enough fresh air into an area to reduce airborne concentrations to some acceptable concentration, which is either some guideline value, regulatory standard, or comfort level. Factors such as contaminant characteristics (e.g., toxicity), quantities generated, seasonal variations, and building configuration have led to standardized formulas describing quantities of air necessary for this type of control.
Local exhaust ventilation, the second fundamental technqiue of industrial contaminant control, attempts to confine a contaminant-generating process as much as possible within an enclosure termed a hood. Through the use of exhaust fans and the hood configuration, the contaminant is captured as close as possible to the source. From there it can be channeled via ductwork to some location where the toxic agent can be controlled for disposal or some appropriate treatment. Recognizing that for effective capture, certain hood/ductwork design and fan capacities are necessary to create enough "capture velocity" for a given contaminant, several empirically derived design formulas are currently the industrial hygiene engineer's guidelines in designing the local exhaust system.
These two approaches characterize the industrial hygienist's attempts at contaminant control and the distinction between the two has usually been clearly defined. In the asbestos control industry however, standard negative air ventilation techniques as well as the features of the typical work site are somewhat different from the seen in the typical industrial or manufacturing setting. The mose obvious difference is that a typical asbestos control site is in a non-industrial structure. This not only requires controls of the obvious occupational exposure within the work containment, but also necessitates that the airborne asbestos dust be confined so that space to protect the surrounding environment.
Additionally, because asbestos control (i.e., removal projects often are conducted in occupied buildings, the potential for exposure of other persons outside the asbestos removal work area to asbestos dust (if not effectively contained) initiates concerns for non-occupational exposure. While there are presently no legal standards for such exposure, the liability implications are far-reaching. Therefore, the very nature of an asbestos project mandates control over the occupational exposure within the work area as well as an environmental control to prevent contamination into the adjacent (and often occupied) spaces. An apparent conflict thus arises, since confining airborne asbestos to the work area inherently produces an increased exposure to personnel working in that area. In turn, increased exposure caused by the confinement necessitates more cumbersome personal protective equipment, and results in a reduction in worker productivity.
Because the common operation of negative pressure enclosures is based upon exhaust fans drawing make-up air through the decontamination unit entrance from the adjacent clean spaces, the system superficially performs the function of dilution ventilation. Current industrial hygiene practice dictates that dilution ventilation is acceptable for low hazard solvents in which quantities of fresh air will lower the concentration of a contaminant below a certain acceptable level. The quantities of air necessary can be calculated since the rate of contaminant (vapors) generation is generally predictable for a specific operation and the air can be distributed to localized areas via ductwork. The nature of asbestos removal, however, is such that the rate of airborne asbestos fiber generation is seldom constant due to the variety of asbestos-containing building products encountered. Even if dilution were applicable to particulates rather than vapors, the dilution capacity that may be adequate in maintaining a specific work area airborne asbestos particulate concentration while removing low asbestos percentage acoustical plaster will not maintain the same airborne concentrations when removing a high percentage deck fireproofing. (Asbestos fireproofing for example, may result in short term personnel exposures from the action limit to 100 fibers/cc depending upon work practices.) Architectural configuration of work zones is another consideration which makes dilution capacity difficult to determine, since office partitions, corridors,, etc., influence air flow and fresh air mixing, and vary greatly from one worksite to the next.
The fact that large quantities of air are exhausted and filtered during the negative pressure asbestos removal process has led to a misconception that the primary purpose of the air filtration is to "clean the air" and thereby reduce the worker exposure. While this may occur to a limited degree, the dilution ventilation capability of the typical negative air arrangement is inferior for reduction of worker exposure since the contaminant of concern, asbestos, has a high toxicity, the generation rate is highly variable, and the asbestos exposure is a result of several point sources within a large area. This is especially true where a high asbestos percentage surface coating (e.g., fireproofing) is being removed.
If asbestos removal is the enclosed work area is analogous to working in a large hood (i.e., enclosed process with exhaust fans), then consideration of the negative air enclosure can be made in terms of local exhaust ventilation. Air filtration units are commonly placed at convenient locations within the work area, usually at the perimeter with an exhaust duct leading to a "clean" area outside the work zone. In the alternative, the intake force of the filter may protrude through the containment or isolation barrier of the work zone, while the bulk of the machine which houses the HEPA filter fan and exhaust duct is situated in the adjacent "clean" space. This latter arrangement facilitates cleaning of the unit at the end of work (as opposed to its location within the work areas); regardless of the position of the filter, the velocity of intake air, which defines the ability to capture the generated asbestos dust, is virtually non-existent at any substantial distance from the face of these units. One need only visualize air flow via smoke at various distances to verify that the capture velocity into the unit is negligible. Perimeter placement of the air filtration device as described above can be characterized, in terms of local exhaust ventilation, as a flanged hood. The air velocity into such a hood is described by the formula: ##EQU1## where: Q=volume of air exhaust in cubic feet per minute
A=area of the hood opening (approximately 3.35 square feet for the common 22 inch square intake)
x=distance from the hood in feet
V=velocity of air at distance X in feet per minute
The two areas of highest air velocity in a work area are the decontamination entrance (theoretically the only make-up air inlet) and the intake face of the air filtration devices. The distance between these two locations is characterized by a negligible flow of air with "dead spots" (a common problem in dilution ventilation) and virtually no air exchanges depending on the dimensions and non-uniformity (i.e., alcoves, office partitions, etc.) of the work area.
Considerations up to this point have been with regard to quiescent, inactive conditions. However, when one considers the high activity in the asbestos removal zone (work area) and the fact that simply walking at a normal pace generates air flow of 50-70 feet per minute (fpm), it is quite unreasonable to expect air filtration devices to substantially reduce personnel exposure when their "capture velocity" is 140-180 feet per minute at a one foot distance, and less than 75 feet per minute at two feet from the intake. (This can be compared to the recommended velocity for local exhaust for an enclosed asbestos debagging operation in industry of 200 feet per minute in an enclosed hood.)
The design of negative air systems too often only gives consideration to total air volumes exhausted without recognizing the characteristics of exhaust ventilation. The proximity of the exhaust units to the worker's removal activity within the work area is more a determining factor than total air flow if a local exhaust capability is desired. Unfortunately, workmen are not inclined to position air filtration devices close enough (i.e., within a foot) to the actual removal activity for effective collection of airborne asbestos dust. While the filtration devices can be equipped with an intake manifold and extended flex duct (12 inch diameter), the flow of air into a round open duct is described as ##EQU2##
This provides at best a capture velocity of 140-180 feet per minute at a one foot distance from the dust opening, and less than 50 feet per minute at a distance of two feet. Thus, normal work activity negates any local exhaust ventilation capability for most asbestos work areas, since no substantial velocity exists for airborne asbestos to be captured by air filtration devices.
The current practice in the asbestos industry is to specify four air changes per hour for the work enclosure. However, determination of ventilation requirements based upon air changes is generally viewed as an unacceptable criteria by ventilation engineers, but is an unfortunate convenience due to the variability of exposure in asbestos work and the nature of changing work sites as previously discussed. The four air changes per hour "standard" is best viewed not as a method of controlling exposure to workers, but rather as a guideline to exhaust a sufficient quantity of air to maintain the negative static pressure within the work area. The guideline static pressure differential of 0.02 inch w.g. has also become standard, and is generally accepted as sufficient since this will produce noticeable drafts around windows, doors, etc. in general building ventilation. An effectively contained asbestos removal zone should contain only small leaks (if any), and with a draft initiated by a 0.02 inch w.g. differential, escape of airborne asbestos through such openings should be prevented. The fact that the exhaust from the air filtration units is filtered enables discharge of uncontaminated air to the surroundings, but does not necessarily relate to any appreciable reduction in work exposure within the contained work area during active removal.
OBJECT OF THE INVENTION
It is an object of this invention to provide an improved method and apparatus for use in conjunction with a negative air environment for asbestos removal from a confined area.
It is an object of this invention to provide an improved distribution of make-up for asbestos removal from a confined area.
It is an object of this invention to provide a method of negative pressure asbestos removal from a confined area wherein localized make-up air is directed to the site of asbestos removal activity.
It is an object of this invention to provide an improved method of negative pressure asbestos removal from a confined area wherein air flow within the removal area or work zone is described in terms of desired air velocity and not simply air changes per hour.
It is an object of this invention to provide a method for more effectively entraining asbestos fibers for removal by filtration equipment.
It is an object of this invention to provide a method of negative pressure asbestos removal from a confined area wherein the make-up air can be obtained directly from outside the structure where the asbestos is being removed.
It is an object of this invention to provide a manifold for use in a method of negative pressure asbestos removal from a confined area so that make-up air to the confined area can be obtained directly from outside the structure.
It is an object of this invention to provide a manifold for use in a method of negative pressure asbestos removal from a confined area wherein the amount of make-up air admitted into the confined work area can be adjusted.
It is an object of this invention to provide a method of negative pressure asbestos removal from a confined area wherein make-up air can be obtained from inside the structure while by-passing the usual decontamination unit.
It is an object of this invention to provide a manifold for obtaining make-up air in a process of negative pressure asbestos removal from a confined area from inside the structure while by-passing the decontamination unit.
It is an object of this invention to provide a method of negative pressure asbestos removal from a confined area wherein the make-up air flow into the removal area or work zone can be increased with a minimum diminishment of negative pressure differential.
SUMMARY OF THE INVENTION
These and other objects of this negative pressure asbestos removal invention are achieved by providing a method for removing airborne contaminant material from a work area where contaminant material is being removed by isolating the work area from the surrounding environment and providing at least one entrance into said isolated work area. A negative pressure is created within the isolated work area by exhausting air therefrom and make-up air is ducted into the isolated work area directly to the vicinity where the contaminant material is being removed in order to entrain the airborne contaminant material created when the contaminant material is being removed. The air containing the entrained contaminants is exhausted from the isolated work area and filtered to remove the contaminant material therefrom.
In order to perform the method, the invention also provides a manifold for placement in a window frame within the isolated work area. The manifold has a plurality of ports therethrough with sleeves attached to the ports on the side of port within work area. Ducting is connected to the ports to conduct air incoming through the ports directly to the vicinity where the contaminant material is being removed. A damper is provided within the sleeve to control the air flow through the sleeve and duct. The end of the duct opposite the end connected to the sleeve has a closure member which closes the duct in the event the air pressure within the work area becomes greater than the air pressure within the duct.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and many of the attendant advantages of the instant invention will become more readily appreciated when the same become better understood by reference to the following detailed description considered in conjunction with the accompanying formal drawings wherein:
FIG. 1 is a schematic drawing showing the present invention in a contaminated work area;
FIG. 2 is a perspective view showing the manifold of the present invention;
FIG. 3 is a side plan view showing an alternative embodiment of the manifold and ducting of the present invention;
FIG. 4 is a perspective view of the duct closure of the present invention;
FIG. 5 is a perspective of the alternate embodiment of the manifold of the present invention shown in FIG. 3;
FIG. 6 is a graphical representation of static pressure differential verses the number of dampers opened; and
FIG. 7 is an enlarged section view taken along the line 7--7 in FIG. 2.
DETAILED DESCRIPTION OF THE INVENTION
It is known in the art of asbestos removal, particularly for asbestos removal from ceiling insulations, to seal all points of penetration into the work space and to cover the floors, walls and horizontal surfaces with plastic sheeting to in essence provide an artifical bubble with the only entrance into the bubble being through a special area which serves as the workers' access and decontamination facility. Fans with high efficiency HEPA filters (exhaust units) are situated within the enclosed or confined work area to exhaust air from within the work area or in the alternative the exhaust units are located outside the work area with only the intake ducted into the contaminated area. Make-up air is provided only through the access/decontamination unit. The constant removal of large volumes of filtered air from within the work area by these HEPA filter units creates a negative static pressure relative to the surrounding spaces. Air flow through any possible openings would therefore be into, and not out of, the work space.
The present invention relies on much the same principles of providing a negative pressure enclosure; however, the present invention provides a more effective source of make-up air than simply allowing the air to enter through the access/decontamination unit, increases the velocity of make-up air and thus the particulate capture of entrapment ability of the make-up air, and provides the make-up air directly at the asbestos removal location.
Referring in detail to the various figures of the drawings wherein like reference characters refer to like features, the method and apparatus of the present invention are graphically presented.
As shown schematically in FIG. 1, a contaminated work area 10 is provided which is completely prepared as known in the prior art by sealing all penetrations into the space, and by covering the floors, the walls and all horizontal surfaces with plastic sheeting. An isolation barrier 11 separates the work area 10 from the non-contaminated area 12. A decontamination unit 20 like that known in the prior art is provided as the sole access for workers and supplies into the work area 10. Within the work area 10 are specific work sites 13 denoted by broken lines wherein asbestos removal activity is conducted by the workers. The work area 10 also has windows 15 thereinto. These windows 15 are preferably sealed, except as described later herein. A plurality of HEPA equipped exhaust units 16 are provided within the area 10 to exhaust air therefrom. This arrangement as shown in FIG. 1 is essentially the same as the standard negative pressure asbestos removal environment, except for the specific location of the HEPA units, which will be discussed later.
In the present invention, rather than only provide make-up air (Arrow A, FIG. 1.) through the decontamination unit 20, which is the known method, an adjustable manifold 100 is positioned into one or more of the windows 15 from which the glass has been removed to allow make-up air to enter into the workspace 10 (Arrow B, FIG. 1.) Connected to the manifold 100 are ducts 200. These ducts 200 are lightweight and are of sufficient length to be directed easily to each of the work sites 13 so that the make-up air is expelled directly at each work site 13. The make-up air thus enters through the manifold 100 and flows directly to the work site 13. Like the prior methods, make-up air may also enter uncontrolled through the decontamination unit 20, however, it is preferred to have the make-up air enter throught the manifold where the amount of air can be controlled.
A more detailed view of the preferred embodiment of the adjustable manifold 100 is shown in FIG. 2. The manifold 100 includes a backboard 102 which fits into and is sealed (such as by sealing the edges by duct tape) within the frame of the window 15 from which the glass has been removed. Through the backboard 102 are a plurality (in this instance, eight) cut-out holes or ports 104(a-h). As shown at the upper left hand port 104(a), a sheet metal sleeve 106 is attached in an air-tight manner through the port 104(a). (While a plurality of sleeves 106 may be supplied, one each through the ports 104(a-h), in order to simplify the description, reference will be made to only one sleeve 106.) As better seen in FIG. 7, within the sleeve 106 is a rotatable circular damper 108 of the type usually found in a duct. The damper 108 includes a circular disk 110 rotatably mounted in the sleeve 106 on two pivot pins 111, 112 respectively. A knob 113 is attached to the lower pivot pin 112 which extends through the sleeve 106. By turning the knob 113, the position of the disk 110 within the sleeve 106 can be altered to control the flow of make-up air through the sleeve 106 and port 104.
Flexible ducting 200 is provided for attachment over the outside of the sleeves 106. (Again, for purposes of simplification, the description will be made with respect to a single duct 200 fitted to the sleeve through port 104(b). Additional ducts may be provided for the remaining ports.) Standard canvas spiral flex duct might be used for each of the ducts, or instead of canvas spiral flex duct, smooth, light-weight polyethylene duct may be substituted. The polyethylene material is lighter in weight and provides for a smaller loss in pressure or flow due to reduced friction loss. Furthermore, while ducts of plastic material are preferred, it has been found that spiral plastic ducts are most preferable, because collapsible ducts require so much air flow just to inflate the duct that a substantial reduction in air velocity is created at the duct outlet. In the preferred embodiment, the ducts 200 are clamped onto the sleeve 106 by using a hose clamp 205 which may be screw tightened.
In FIG. 2, positioned over the top four ports 104(a-d) is, preferably, a cabinet 109. This cabinet 109 has a top 114, a bottom 115, two sides 118, 120 and a front panel 122. Through the front panel 122 are four additional cut-out ports 124(a-d) corresponding to and aligned with the cut-out ports 104(a-d) in the backboard 102. As shown in FIG. 2, the ducts 200 pass through the cut-out ports 124(a-d) in the cabinet 109.
The cabinet 109 prevents unwanted manipulation of the dampers 108 once the dampers have been appropriately adjusted for proper air flow and also prevents the ducts from being accidentally removed from the sleeves. Access into the cabinet is gained by providing a hinged door on one of the side panels, thereby creating a door into the cabinet. As shown in FIG. 2, the side panel 118 is formed with a hinged door 119. In order to lock the panel, a hasp 126 and corresponding U-shaped member 128 positioned to receive the opening through the hasp 126 are installed so that a padlock (not shown) can be installed to lock the panel and prevent the panel from being opened.
The manifold 100 shown in FIG. 2 only has the cabinet 109 positioned over four of the cut-out ports 104(a-d) in the backboard. The four additional cut-out ports 104(e-h) are not utilized in this particular embodiment, and accordingly are covered with air-tight seals 132(e-h) which prevent air from entering or exiting through these ports. If it is necessary to provide increased air flow into the work space, a larger cabinet can be installed and additional dampers and ducting can be provided, or more windows can be removed and additional backboards and cabinets installed. Also, the additional cut-out ports 104(e-h) may be used as exit openings for dispelling filtered air from the work area by attaching ducting from the HEPA units to metal sleeves (not shown) fitted through these openings. As further shown in FIG. 7, a flange member 107 is preferably fitted around the sleeve 106 at the cut-out ports 104. These flange members 107 help to increase the air flow into the metal sleeves 106.
The end of one of the ducts 200 extending into the work area 10 is shown in FIGS. 3 and 4. The end of the duct 200 is fitted onto a cap or closure member 400. The cap member 400 includes a sleeve 402 connected to a board member 404 having an openings 405 therein aligned with the sleeve 402. The duct member 200 fits tightly around the sleeve 402 and may be secured thereto by a hose clamp (not shown). Affixed to the board member 404 at the top edge 406 thereof is a light-weight covering or flap 408. The flap 408 can simply be attached to the edge 406 by tape 410 as shown in FIG. 4.
When the damper 108 is adjusted to allow air flow through the duct 200, the air pressure is sufficient to move the flap 408 away from the opening 405 at the end of the duct 200 to allow air to flow into the work area 10. However, should the air pressure (which is maintained in a negative state within the work area) become greater than the pressure within the duct 200, the flap 408 will immediately close by forcing against the board member 404 to seal the opening 405, and thus prohibit any contaminated air within the work area 10 from passing outward through the duct 200. Thus, contaminated air cannot escape through the duct 200 due to increase of pressure within the work area 10.
Within each contaminated work area 10, at least one window 15 is removed and a manifold 100 installed within that window. The manifold 100, of course, is constructed to the appropriate size to fit the window or the opening created in the window. The desired number of ducts 200 are attached at one end to the sleeves 106 and the opposite ends of the ducts connected to the cap members 400 are positioned at the specific work sites 13 where asbestos removal activity is being conducted. As shown in FIG. 4, because the ducts are made of lightweight material, they can be easily suspended from the ceiling grid 142 by means of wires 144.
While the HEPA units 16 may be positioned anywhere within the contaminated area 10 and ducted out of the area through ports in the manifold, it has been found that removal of the airborne contaminant material, e.g., asbestos, is greatly enhanced by positioning the HEPA units at the end of the contaminated area 10 in the direction which the removal work is proceeding. Furthermore, it has been determined that providing a number of HEPA units across the end of the contaminated area as shown in FIG. 2 is much more effective at removing the contaminated air than simply providing one large, centrally located unit. By spacing numerous units across the end of the contaminated area, it appears that an "air sweep" affect is created in the contaminated area 10 which causes an air flow in one direction in the contaminated area similar to that which is created on a smaller scale by providing a slotted hood in a hood-type ventilation chamber. Accordingly, it is preferred that a plurality of HEPA units 16 be provided across one end of the contaminated area. These units can be exhausted through ducts 204 through manifolds 101 positioned in windows 15 which only allow exhaust through the ports and do not have any inlet ducts connected thereto.
Before asbestos removal begins, the HEPA units are started to bring the work area 10 into a negative pressure condition with respect to the surrounding environment. The dampers 108 are opened and air from the outside is allowed to flow through the ducts 200 to the work sites 13 within the negative pressure work area 10. Unlike the prior art processes where make-up air enters only through an opening in the decontamination facility 20, the entrance from the decontamination facility 20 in this instance can be closed or sealed from the work area 10 so that the flow of all make-up is controlled through the manifold 100. As discussed previously, when the damper controls are properly adjusted the manifold cabinet 109 can be locked to prevent any further adjustment of the manifold unless specifically required.
Oftentimes it is not possible to position the manifold 100 in a window, especially when none is available or the work area 10 is isolated from the exterior windows. In such instances it is necessary to install the manifold 100 through the isolation barrier 11 in order to obtain make-up air from the non-contaminated area 12 outside the contaminated work area 10. As shown in FIGS. 1, 3 and 5, a manifold 300 is positioned through the isolation barrier 11 and is connected to a duct 200 which extends into the contaminated work area 10. While there is no particular requirement for the material used for the isolation barrier 11, so long as it functions to isolate the non-contaminated clean area 12 from the contaminated work area 10, it is preferred that isolation barrier be of a rigid material, such as plywood.
The manifold 300 includes a cabinet 309 surrounding an opening or port 304 through the isolation barrier 11. Extending through the port 304 is a metal sleeve 306 attached to the isolation barrier in an air-tight manner. The sleeve 306 has a damper 308 therein constructed similarly to the damper 108 described previously. The sleeve 306 has an extended portion 307 which projects through the port 304 into the contaminated area 10 as shown in FIG. 3. The cabinet 309 is affixed to the isolation barrier 11 and includes top and bottom panels 314, 315 and side panels 318, 320. Attached by hinges 317 is an end panel 322 which can be moved between an open position exposing the sleeve 306 or a closed position which isolates the sleeve 306 within cabinet 309 and prohibits communication between the sleeve 306 and the non-contaminated area 12. A locking arrangement (not shown) may also be provided.
As described in the previous embodiments, the duct 200 is fitted and clamped onto the extended portion 307 of the sleeve 306 within the contaminated work area 10. Attached to the end of the duct 200 within the work area 10 is a cap member 400 with a moveable flap 408, as previously discussed.
By using the manifold 300, it is possible to obtain make-up air from the non-contaminated area 12 and deliver it into the contaminated work area 10 by simply opening the end panel 322 and adjusting the damper control 308 in the sleeve 306. While FIG. 1 shows only two ports 304, 304 through the isolation barrier 11, it is readily apparent that additional ports may be provided.
The embodiment shown in FIG. 1 shows the generally preferred arrangement of ducting 200 and HEPA unit placement. The ducts 200 from either window manifolds 100 or the isolation barrier manifolds 300 (or both) are situated in the work area 10 so that they are up stream of the work site where the contaminant material is being removed. In this manner, the air exiting the duct at the work sites entrains the airborne contaminant particles and carries them toward the HEPA units which are downstream from the work sites 13. Asbestos removal proceeds across the work area 10 in the direction of the HEPA units. The air flow from the ducts continuously blows in the direction of the HEPA units 16 to not only act in directing the air toward the filter units, but also to help prevent the contaminant laden air from dispursing rearwardly to areas which have already been cleaned. This helps to speed up the final cleaning of the contaminated area.
As shown in FIG. 1, the ducts 200 are all positioned so that the air flow is directed toward the HEPA units, thereby creating the "air sweep" toward the filter units spaced across the end of the work area discussed earlier. While both manifolds 300 and 100 are shown as being used in FIG. 1, the combined use of both is optional. Also, make-up air (arrow A) can be provided through the decontamination unit, as known in the prior art, but it is not as easily controlled as by adjusting the dampers in the manifolds.
Also, shown in FIG. 1 by way of demonstration, an HEPA unit 17 is shown connected to a manifold 100. As discussed earlier, the manifolds 100 may also be used to connect HEPA filtering units thereto through the lower ports 104(e-h).
Several case studies using the manifold and ducted localized make-up air technique of this invention have been completed. The projects involved asbestos removal from several floors of two metropolitan high rise buildings. One building contained 95% amosite fireproofing sprayed and tamped onto the corrugated steel deck, while the other building contained 20-25% chrysotile fireproofing sprayed onto the beams with considerable overspray onto adjacent structure.
Standard design of negative pressure enclosures dictates that the primary air make-up should be through the decontamination chamber, in which air enters through an approximately 20 square foot opening or doorway and rapidly disperses when entering into the larger work space. Except for the short time while the workers' are entering and exiting the work area, when the air flow through the decontamination unit prevents the workers from possibly bringing airborne asbestos back into clean spaces, this air flow does not serve any substantial purpose other than to provide make-up air volume. By shutting the decontamination entrance and supplying air either through the extended flex ducts connected to the strategically situated window manifolds, a controlled, directed air stream was produced. This helped to alleviate the static dead spots typical of an asbestos removal zone (such as where make-up air enters only through the decontamination entrance) and provided better movement of the airborne filters to the filtration devices for eventual capture.
In the amosite-containing building, air was evacuated via air filtration devices from various size work zones (5,000 ft-20,000 ft) which translated into the equivalent of approximately twelve air changes per hour. Wooden manifolds such as those described herein were installed in various windows to control the make-up air. Recognizing that a pressure drop in the flex duct attached to the inlets would limit the length of the extension of the duct into the work area, manifolds were spaced based upon anticipated air flow capabilities. This allowed an air supply to be controlled and directed as work activities progressed. Cost factors (e.g., removal and replacement of windows) influence the number of windows that can realistically be used. Therefore, full window plywood manifolds were constructed to serve both as supply air as well as a filtration exhaust. In the second building, a 40,000 square feet work zone (25% chrysotile) was arranged in similar fashion with an exhaust equivalent of eight air changes per hour.
Three parameters were identified to evaluate the effectiveness of the altered ventilation configuration. The primary goal was to increase and control the velocity of air entering the work area. Therefore, determination of velocity of make-up air through the auxiliary ventilation ports at various damper configurations, and at some distance downstream at the mouth of attached flex duct, was necessary.
In the amosite containing building, several field tests determined the velocity of the make-up air at the inlets to be 1100-1500 feet per minute. Ducting the make-up air approximately 50 feet produced a velocity at the face of the open duct of 400-800 feet per minute under normal asbestos work zone conditions.
In the second building, velocity measurements at the open face of thirty foot ducts were 800 feet per minute.
To monitor differential pressures between the isolated work area and the surrounding area, 1/4 polyethylene pneumatic tubing was installed with two open taps in each of four quadrants of the occupied floor above. Each of the lines was connected to a Dwyer manometer permanently installed in or adjacent to the decontamination chamber of the work area floor below. These were compared to a static line installed in the work area with the open tap in the approximate center of the work area.
The supply and return ductwork of the building's HVAC system which supplied the work floor were blanked, while the fans controlling the adjacent floors operated on a modified schedule to increase the positive pressure on the adjacent occupied floors.
The dampers of the window mounted manifolds were then individually opened and velocity measurements recorded as indicated by a factory calibrated ALNOR (Model 6000) velometer. In so doing, not only were individual velocities recorded, but simultaneous static pressure measurements, as an average of the static input lines from the floor above, were recorded as the ports were opened. These were compared to the static pressure in the work area and in the decontamination chamber.
Finally, a 30 foot canvas spiral flex duct was connected to one of the ports and extended to the site of asbestos removal with two right angles. An average of eight readings were also taken at the face of this open, extended flex duct to test the velocity loss (pressure drop) caused by the anticipated work practice of ducting the air flow.
Average velocities at the inlet port varied from approximately 1,050 feet per minutes to 1,400 feet per minute, and were consistent throughout the test procedures. No decrease in velocity was noted as a result of opening all of the ports to the maximum of twelve tested.
The ducting of air from the ports via the length of flex duct indicated an approximate 40% loss in velocity, dropping from an average of 1,400 feet per minute to 850 feet per minute. (This agrees reasonably well with theoretical predictions of loss through this type of ductwork with the length and configuration tested.)
A drop in static pressure between the work area and the occupied floor above, as the various manifold ports were opened, was anticipated and fairly well predicted in a straight line relationship (FIG. 6). However, the differential did not go below 0.08 inch of water, which still exceeds the current accepted 0.02 inch of water differential between work area and adjacent spaces.
The configuration of the inlet ports only permitted velocity measurements at approximately two feet from the intake of outside air (where flex ducts were not attached). This area would have been characterized by some turbulence (vena contracta) and which would have contributed to some variability in the velocity measurement. It should also be noted that duct flow evaluation was performed with a canvas spiral flex duct (substantial velocity loss due to friction) having two right angle elbows to simulate worst case conditions. Smooth, light-weight polyethylene duct if properly supported at elbows and junctions is a better duct material due to lower friction loss. In addition, if the duct/port locations can be situated so that only one right angle would be necessary to effectively direct air flows, friction losses are reduced as well.
The data indicate that a substantial flow of air can be ducted and directed to the specific work site by manipulation of the make-up air supply. This is particularly significant in a larger asbestos work area such as an entire evacuated floor of an office building, where the distances involved present the problem of sizable dead spots and negligible air flow with make-up air only being admitted through the decontamination unit. While the use of the standard corrugated flex duct poses large velocity/pressure losses, (due to friction) which would be unacceptable in most ventilation application, the lengths of ducting necessary in even a large work zone are usually short enough and the velocities low enough that this does not pose a significant hindrance. While there was no specific desired velocity targeted, a velocity of 500-850 feet per minute from a sustantial length of duct was viewed as an improvement over the standard negative air enclosure conditions where make-up air is provided only through the decontamination unit.
Loss of a negative pressure differential (the primary engineering control during asbestos removal), is a potential problem any time substantial quantities of air are allowed into a negative pressure enclosure. Therefore, any auxiliary make-up scheme must be diligently monitored for loss of pressure differential, and adjusted accordingly. As can be seen from the graph in FIG. 6, even though there was a loss in negative pressure differential as more ports were opened, the differential remained well above the currently accepted 0.02 inch of water.
The manually controlled dampers were sufficient to control the auxiliary air flow and are essential to ensure pressure differentials between the work area and surrounding spaces are maintained. Control of unusual flow rates as may develop via changing atmospheric conditions must also be considered, and for this reason, damper controlled ports are necessary.
The use of air changes per hour as a criteria for engineering controls has well recognized shortcomings. Here, a negative air circulation scheme has been described in terms of spedific velocity and negative pressure differential requirements for a specific operation. This is a solution to some of the problems inherent in the typical negative air enclosure of asbestos work sites.
Without further elaboration the foregoing will so fully illustrate our invention that others may, by applying current or future knowledge, adopt the same for use under various conditions of service.
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A method of removing airborne contaminant material from a work area by isolating the work area from the surrounding environment, providing at least one entrance into the isolated work area, and creating a negative pressure within the isolated work area by exhausting the air therefrom. Make-up air is introduced into the isolated work area by ducting the air directly to the vicinity where the contaminant material is being removed in order to entrap airborne contaminant material created when the contaminate material is being removed. The air being exhausted from the isolated work area is filtered to remove the contaminant material therefrom. A manifold and ducting assembly are also provided to regulate and direct the flow of make-up air to the vicinity where the contaminatn material is being removed.
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BACKGROUND OF THE INVENTION
This invention relates to framing systems and, more particularly, to connectors for interconnecting elongated frame members into structurally stable, freestanding frames, building frame modules, lattice-type framework and the like.
Space structures may be defined as two and three-dimensional assemblies of elements resisting loads which can be applied at any point, inclined at any angle to the surface of the structure and acting in any direction. These structures can be built up economically from simple prefabricated units, in most cases of standard size and shape. Such units, mass produced in the factory, can be easily and rapidly assembled on site by semi-skilled labor. At the same time, the small size of the units simplifies greatly the problems of handling and transportation.
Many things influenced the rapid recent development of space frames, including the reduction in the complexity of analysis of such systems and in the joining of several members in space at different angles. These difficulties have been overcome by several present day connectors produced mainly for prefabricated steel or aluminum structures. Through mass production, their cost has been reduced and their use enables the erection of highly complex space structures by semi-skilled personnel.
A connector is the most important part of any prefabricated system and the final commercial success relies directly on its effectiveness and simplicity. Many different types of connectors have been proposed for space structures; some of them have been used in practice, but only a few have survived the test of time.
Heretofore, designers have tried to produce a universal connector suitable for many types of structures, but have ended up with an unnecessarily complex connector consisting of too many parts.
Thus, a need exists for a connector and the resulting framing structure which has the advantage of flexibility in use, yet is simple to manufacture and easy to use by semi-skilled personnel.
DESCRIPTION OF THE PRIOR ART
The Triodetic Structures Limited of Ottawa, Ontario, Canada, developed a joint for connecting space structures involving the cold forming of the ends of structural members to produce a key and an extruded or formed hub connection into which the members fit.
The MERO-TRIGONAL system of Dr. Ihg Max Mengeringhauser discloses in an article entitled Space Grid Structures, by John Barrego, The MIT Press, copyrighted 1968, a threaded steel ball which enables up to eight members to be connected to any of the three planes at angles of 45 degrees.
U.S. Pat. No. 3,921,360 discloses a connector for a framework-type structure having the shape of an irregular polyhedron.
U.S. Pat. No. 3,255,721 discloses a joint which will receive structural members at several mutually perpendicular angles.
U.S. Pat. No. 2,371,493 discloses a metallic splice member having angularly extending arms, each of which has a dovetail cross-sectional formation received within correspondingly formed slots provided in the adjacent ends of angularly extending frame bars.
U.S. Pat. No. 3,747,261 discloses a ball and socket linkage for polyhedral members utilizing a connector in the shape of a cube to receive the ball-shaped member.
U.S. Pat. No. 3,982,841 discloses a connector 20 having slots which limit the movement of the structural members.
U.S. Pat. No. 3,648,404 discloses a ball and socket connector with the balls on the connector rather than on the structural member.
U.S. Pat. No. 3,600,825 discloses triangular framing members.
SUMMARY OF THE INVENTION
In accordance with the invention claimed, a new and improved space framing system and connectors therefor are provided for the erection of supporting lattice-type frameworks for buildings, furnishing for the building, shelving and the like comprising elongated structural members or struts which can be joined to one another by novel connectors to form the desired shape framework. The struts and the connectors may be fabricated off site and transported to and assembled at the sites where the framework is to be erected.
It is, therefore, one object of this invention to provide a new and improved structural framework.
Another object of this invention is to provide a new and improved lattice-type support structure for buildings and the like, which component parts may be economically fabricated at a location remote from the building site and then quickly and economically transported to and assembled at the building site.
A further object of this invention is to provide new and improved connectors for coupling the elongated structural members or struts forming a lattice-type framework which assures the structural stability of the framework, enables the use of struts of identical or different lengths, and avoids the necessity of bending or otherwise distorting the struts to effect the final assembly.
A still further object of this invention is to provide a new and improved connector arm that is removably attached to an end of an elongated structural member and adapted to engage and be firmly held by an appropriately sized aperture located in a connector.
A still further object of this invention is to provide a new and improved connector assembly that is removably inserted into the end of an elongated, tubular frame member to form a connection therewith.
A still further object of this invention is to provide a new and improved framing system which can be erected by semi-skilled labor.
A still further object of this invention is to provide a new and improved framing system which may have three or more panels intersecting along a central axis to operate in a fixed, hinged or sliding arrangement at any angle while independent of the other panels.
Further objects and advantages of the invention will become apparent as the following description proceeds; and the features of novelty which characterize this invention will be pointed out with particularity in the claims annexed to and forming part of this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
This invention may be more readily described by reference to the drawings, in which:
FIG. 1 is a perspective view of a space frame with the far side removed for purposes of clarity, the elongated members of which are interconnected by a plurality of different types of connector assemblies embodying the invention;
FIG. 2 is an exploded perspective view of one of the connectors and connector arm assemblies shown in FIG. 1;
FIG. 3 is a cross-sectional view of FIG. 2 taken along the line 3--3;
FIG. 3A is an enlarged perspective view of a bearing dish for a movable connector arm assembly;
FIG. 4 is an illustration of an immovable connector arm for use in the structure shown in FIG. 2;
FIG. 5 is a view of a modification of the immovable connector arm shown in FIG. 4 in a different arm extended position;
FIG. 5A is a modification of the socket connecting end of the connector arms shown in FIGS. 4 and 5 disclosing a snap-on connecting means;
FIG. 6 is a partial cross-sectional view of FIG. 2 taken along the line 6--6;
FIG. 7 is a perspective view of a modification of a male extension plug formed in a triangular bar configuration;
FIG. 7A is a cross-sectional view of FIG. 7 taken along the line 7A--7A;
FIG. 8 is a perspective view of a further modification of the male extension plug shown in FIG. 7;
FIGS. 9-14 are partial perspective views of further modifications of the tubular frame members shown in FIGS. 1, 2, 6 and 29;
FIGS. 15A-15D are cross-sectional views of the tubular frame member in FIGS. 9-14;
FIG. 16 is an exploded perspective view of combination of connectors and a partial view of a connector arm assembly embodying the invention;
FIG. 17 is a cross-sectional view of FIG. 16 taken along the line 17--17;
FIG. 18 is an exploded view partly in section of an adaptor for use with the connector shown;
FIG. 19 is an exploded view of a pair of connectors interconnected by an adaptor that, for example, is shown connected with a movable connector arm assembly;
FIG. 20 is a perspective view of a modification of an anchor for use movable connector arms shown in FIG. 19;
FIG. 21 is a perspective view of a further modification of the anchors shown in FIGS. 19 and 20;
FIG. 22 is a plan view of a further modification of the connector arm shown in FIGS. 2, 4, 5 and 19;
FIGS. 23-28 are cross-sectional views of various modifications of tubular frame members;
FIG. 29 is a partial perspective view partly in cross-section of a portion of a structure employing a pair of different connectors and various connector arm assemblies for use therewith, some being angularly adjustable and some being stationary; and
FIG. 30 comprises a connector with some of its faces having more than one socket.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring more particularly to the drawings by characters of reference, FIG. 1 discloses, for purposes of illustration, a space frame 30 usable for two- and threedimensional framing systems formed of a plurality of homogeneous parts. Although a building is shown which may be a greenhouse, the framing system may be used to create many other types of architectural structures differing in size and shape, such as geodesic domes and space structures. Not only is the framing system usable for various building configurations, but it may be easily adapted for the creation of stair fixtures, display cabinets and cases, window frames, shelving components in a storage system, fixtures, such as hand rails, bathroom fixtures, and the like.
As shown in FIG. 1, framework 31 is formed of a plurality of tubular framing members 32 interconnected at various corners and joints by a plurality of connector assemblies forming joiner hubs and associated connector arms which are shown in the various figures of the drawings.
The joiner hubs comprise universal and fixed ball and socket connector arms which join one or more elongated members such as the tubular framing arms 32 together with the arms being capable of motion in all directions relative to the joint. Since the linkages of this invention permit 360 degrees of rotation of the connector arm assemblies relative to one another, it enables an almost unlimited variation of assemblages thereof.
FIGS. 2-4 and 6 illustrate a basic connector 33 in this instance formed in the shape of a cube, having six faces 35 each having a socket 36 formed in its center. A fixed ball assembly 37 applied to one end of a connector arm 38 is threadedly connected to a male extension plug 39 although a suitable snap-on connection may be employed. Plug 39 is inserted in one end of tubular framing member 32 in the manner shown in FIG. 2 and held therein by connections, for example, set screws 40 extending through the connector arms into threaded holes 41 in plug 39, as shown in FIG. 6.
The fixed ball assembly 37 is adapted to threadedly engage or snap fit into socket 36 with its concave portion extending into a pocket or hole therein. The pocket 42 is in the shape of a partial sphere positioned at the end of each hole formed by the socket and is provided with an expansion ring or groove 43 extending outward of the inside periphery of the hole, in the manner shown in FIG. 3, to form an expansion ring groove for use with a connector arm employing an expansion flange around its ball-shaped configuration as hereinafter explained.
The fixed ball assembly, as shown in FIGS. 2 and 4, comprises a partial sphere 45 integrally formed with an externally threaded base 46 which is necked down to a spherical configuration or ball projection 47 formed at one end of connector arm 38. The other end of connector arm 38 is provided with an externally threaded shank 48 for threadedly engaging internally with the extension plug 39, as shown in FIG. 6. Although connector arm 38 is shown as being threadedly connected with extension plug 39, a friction or snap-on connection may be used and fall within the scope of this invention.
With either a threaded or snap-on connection, connector arm 38 is arranged to extend outwardly of connector 33 in a perpendicular direction from one of its faces 35.
As noted from FIG. 2, a mounting plate 49 having at least one externally threaded hub 50 extending laterally outwardly from one face thereof may be used to threadedly engage with its spherically shaped end 51 one of the sockets 36 in connector 33. Plate 49 may be secured to a base (not shown) by pin connections such as screws or bolts extending through holes 52 formed in each corner thereof.
FIG. 3A illustrates an insert 53 forming a seat 54 that may be inserted into the open threaded end of a universal or movable ball assembly as shown in FIGS. 19 and 29.
FIG. 5 illustrates a modification of the connector arm 38 shown in FIGS. 2, 4 and 6 wherein connector arm 38' is rigidly formed with the fixed ball assembly 37 to extend outwardly thereof in a non-perpendicular arrangement.
FIG. 5A illustrates a modification of the connector arms 38 and 38' shown in FIGS. 4 and 5 wherein the connector arm 38" comprises a partial sphere 45' integrally formed with a base 46' which is necked down to a spherical configuration of ball projection 47'. A flange 45A, formed of a suitable resilient material and of any suitable shape, is arranged around the periphery of the partial sphere 45', as shown, and tapered so as to move into the expansion grooves 43 of a connector such as connector 33, shown in FIGS. 2 and 3. Thus, the ball assemblies of the connector arms 38 and 38' may be fabricated without the threaded connecting means of FIGS. 2 and 3 and in place provided with the expansion ring 45A and make a "snap-on" connection with the interior of connector 33 and fall within the scope of this invention. This "snap-on" connection may be utilized by connector arm 38" even though the interior of the sockets of connector 33 may be provided with the interior threads shown in FIG. 3. Thus, connector 33 may be used with both threaded and snap-on connector arms.
It should be noted that when the ball head of any of the connector arms disclosed, whether it be a threaded or snap-on connector arrangement, rests within the pocket 42, the spherical surface of the head engages the interior of the pocket forming a bearing surface for the spherical ends of spheres 45, 45', thus absorbing some of the forces on the arm otherwise applied only to its threaded or "snap-on" connecting means.
The "snap-on" connecting means, i.e., flange 45A and groove 43, may be used on the connector arms 38, 38' alone or in combination with its threaded connection 37A as shown by the combination of threaded connection and expansion flange arrangement on the adaptor plugs 79 and 82 of FIGS. 18 and 19.
In FIGS. 2 and 4, the male extension plug 39 is shown as being of a cylindrical configuration for connecting with a stretcher or tubular framing member 32.
FIGS. 7 and 7A illustrate a modification of this plug wherein extension plug 54 comprises a triangular configuration having a longitudinally extending, axially arranged bore 55 extending therein from its base plate end 56. Bore 55 is arranged for threadedly receiving therein the threaded end of one of the connector arms 38, 38'. As heretofore explained, bore 55 may be adapted to slidingly receiving and engaging in a snap-on arrangement the connector arms, if so desired.
The extension plug 54 is further provided with one or more spacedly-arranged threaded holes 57 for receiving therein pin connectors such as bolts (not shown) which clamp thereon a stretcher arm or tubular framing member 58 shown in FIG. 10. Framing member 58 is positioned on plug 54 in substantially the same manner as tubular framing member 32 telescopically or slidingly fits its associated male extension plug 39. Holes 59 in the tubular framing member 58 are used for receiving pins or bolts (not shown) for clamping the male plug and tubular framing member together.
FIG. 8 illustrates a further modification of the male extension plugs 39 and 54 shown in FIGS. 2, 6 and 7 wherein an extension plug 60 comprising a rectangular configuration having a square cross-sectional shape is telescopically or slidingly connected to a suitable tubular framing member in the manner shown in FIGS. 9, 11 and 12.
Extension plug 60 further comprises a base 61 having a bore 62 extending inwardly thereof along its axis a predetermined distance and having an internally threaded end 63 for receiving a threaded shank end 48 of a connector arm such as connector arm 38 of FIG. 4. A pair of internally threaded holes 64 are provided in one of the faces 65 of the extension plug 60 for threadedly receiving pin connections such as bolts extending through a suitable framing member telescopically or slidingly associated therewith in the same arrangement as described above for extension plugs 39 and 54. Other like holes may be formed in any of the other faces 65 of extension plug 60, if so desired.
Framing member 66 and 67 shown in FIGS. 9 and 11, respectively, may be bolted to one or more of the faces of extension plug 60 in the manner defined for the other extension plugs. FIG. 11 shows framing member 67 as comprising two members 67A and 67B which may be, for example, attached to opposite sides of extension plug 60.
FIGS. 12-14 illustrate further modifications of framing members for use with the extension plugs 54 and 60 of FIGS. 7 and 8. In FIG. 12, the framing member 68 comprises a platform 69 supported by a pair of diagonally-arranged legs 70, 71 with either the top or legs or both being provided with bolt holes 72 for using in securing the framing members to one of the male extension plugs 54 or 60 disclosed in FIGS. 7 and 8.
FIG. 13 discloses a framing member 73 which may be attached to extension plugs 54 and 60 by means of pin connections such as bolts extending through holes 74 for threadedly engaging with holes 57 and 64 in plugs 54 and 60, respectively.
FIG. 14 discloses a triangular shaped framing member 75 which may telescopically or slidingly receive therein extension plug 54 and be connected thereto by pins or bolts (not shown) extending through holes 76 selectively positioned therein.
FIGS. 15A--15D illustrate various ways the framing members shown in FIGS. 9-14 may be connected together.
In FIG. 15A, the parts 67A and 67B of framing member 67 are secured to extension plug 68 in the manner shown. In FIG. 15B, the parts 67A and 67B of framing member 67 are secured to framing member 66. In FIG. 15C, the parts 67A and 67B of the framing member 67 are secured to framing member 73 and in FIG. 15D the framing members 66, 68 and 75 are secured together as shown.
FIG. 16 discloses a connector assembly 78 comprising a plurality of different geometrical configurations. As shown, a number of connectors 33 are interconnected by adaptor plugs 79 that are threadedly received by sockets 36 in juxtapositioned like connectors. It should be recognized that these plugs may on one or both ends be formed without the threaded configuration and in place thereof employ the expansion flange 45A of FIG. 5A. Thus, the flanges of the plugs would snap into grooves 43 in sockets 36 in the manner heretofore explained. These plugs make it possible to position like faces 35 of connectors 33 in coplanar touching arrangement.
As shown in FIGS. 16 and 17, a plurality of connectors 80 comprising a different geometrical configuration is provided with sockets 36' and expansion flanges 43' in its various faces 35' to connect with connectors 33 by means of plugs 79 to form, for example, an eight-sided connector 78.
Sockets 36 and 36' in the various connectors 33 and 80 may be used to receive and connect with ball assemblies 37 of various connector arm assemblies 38 and tubular framing members 32 in the manner heretofore defined.
The unused sockets of connectors 33 and 80 may be covered by a suitable cap 81 as shown in FIG. 16.
FIG. 18 illustrates a modification of adaptor plugs 29 wherein adaptor plug 82 comprising two hemispherical ends 83 and 84 each having expansion flanges 85 and 86 are interconnected by an externally threaded portion 87. The smaller hemispherical end 84 is provided with an externally threaded shank 88 for threadedly connecting with a socket 89 in a connector 90. The expansion flange 86 interlocks with the associated groove inside of the socket in connector 90 in the manner explained for connector 33. Connector 90 and its internally threaded socket 89 is smaller than connector 33 and its socket 36 and by means of plug 82 are used to interconnect structural elements of various sizes. As shown, the end 83 of plug 82 is provided with an expansion flange 88 for snap fitting into groove 43' of connector 80.
FIG. 19 is an exploded cross-sectional view of various parts of the disclosure illustrating one method of interconnection. A universal ball assembly 91 is shown connectably to one of the sockets 36 of a connector 33 by means of a bearing dish 92 which is inserted in the spherical opening 42 of the socket. Arm assembly 91 having a ball head 93 is held in the socket by pressure applied thereto by a cap 94 which threadedly engages with the internal threads of socket 36 or with the expansion ring groove if cap 94 is provided with a suitable expansion flange in the manner shown in FIG. 5A. Cap 94 loosely fits around ball head 93 with the remainder of arm assembly 91 extending outwardly thereof through an opening 95 formed in cap 94.
FIGS. 20 and 21 disclose anchors 96 and 97 which may be threadedly or snappingly attached to sockets 36 of connector 33 and used for interconnecting various universal ball assemblies to connector 33.
FIG. 22 discloses a plan view of a modified universal ball assembly 77 shown in FIGS. 19 and 29.
FIGS. 23-28 disclose cross-sectional views of various stretcher or tubular framing members for connecting with connector 33 in the manner shown in the illustrative structural assembly shown in FIG. 29.
FIG. 23 illustrates a cylindrical configuration 98 having a flange 99 extending outwardly thereof for mounting around extension plug 39. A second open cylindrical configuration 100 having a flange 101 extending outwardly thereof is arranged in a limited rotating manner around the outer periphery of the cylindrical configuration 98.
An arcuate cleat 102 having flanges 103 and 104 extending outwardly thereof is arranged to be bolted to plug 39 between flanges 99 and 101 of the cylindrical configurations 98 and 100 by a pin connection or bolt extending through hole 105 into plug 39 to hold them in a fixed or movable orientation, as shown in FIG. 29. As shown in FIG. 29, the cylindrical configuration 98 may be provided with a slot 106 extending partially around its periphery for permitting a pin connection or bolt extending through hole 105 in cleat 102 to reach plug 39 and/or to be used to lock the cylindrical configurations 98 and 100 together.
FIG. 25 illustrates a different relative portion of the cylindrical configurations 98 and 100 held together by a pin connection bolt (not shown) extending through slots 106 and 107 into plug 39 without the benefit of cleat 102.
FIG. 26 illustrates the manner of slidingly receiving two elongated arcuate configurations 108 and 109 which may be bolted to plug 39 in the manner heretofore described to hold these members together to form framing members or cleats for the space frame.
FIG. 27 illustrates a cross-sectional view of a further modification of the framing members or cleats wherein two arcuate protions 110 and 111 are shown which may be bolted to plug 39 in any desirable arrangement.
FIG. 28 illustrates a cross-sectional view of a further modification of the framing members or cleats wherein an arcuate portion 112 fits between a pair of cooperating arms 113 and 114 of a further arcuate portion 115 in the manner shown.
FIG. 29 further illustrates that two cleats 116 and 117 may be fastened to plug 39 by pin connections or bolts (not shown) extending through their slots 118 and 119 to hold cylindrical configurations 98 and 100 in given relative positions.
As shown in FIG. 29, suitable panels 118 may be secured to the various flanges of the stretcher arms or framing members to complete a building or building module.
Although the connectors 33 are shown as having only one socket 36 per face, it should be recognized that more than one socket may be used in each face as shown in FIG. 30 and still fall within the scope of this invention.
FIG. 30 comprises a further modification of connector 33 wherein a cubical configuration 119 is shown having one or more socket 36 formed in one or all of its faces 120. For purposes of illustration, one socket 35 is shown in its top surface and more than one socket 35 is shown in the two sides shown. Each of the sockets is arranged to receive in the manner discussed one of the connector arm assemblies disclosed.
Although but a few embodiments of the present invention have been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.
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A framing system for interconnecting elongated frame members into structurally stable, free-standing frames, building frame modules, lattice-type framework and the like employing novel connectors and associated connector arms.
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FIELD OF THE INVENTION
[0001] The invention concerns a device in an drill string component for percussive rock drilling including a thread for threading together with another drill string component being provided with a complementary thread, wherein the thread includes a thread groove formed by two thread flanks and an intermediate thread bottom, and wherein the thread groove has an essentially equally shaped sectional form along its axial extension. The invention also concerns a thread joint and a drill string component.
BACKGROUND OF THE INVENTION
[0002] In order to joint drill string components for percussive rock drilling it is well known to use so called trapezoidal threads, wherein one end of a drill string component comprising a male thread is threaded together with a female thread at an end of the next drill string component. Alternatively, both ends of drill rods to be joined are threaded together over sleeves being provided with female threads at both ends.
[0003] Thread joints for drill string components or percussive rock drilling are subjected to high instantaneous loads and hostile environments. The threaded joints have to be drawn to moment levels that prevent loosening during operation, which means that large forces influence the respective thread wall of the male as well as the female thread. The working life length of the drill string components is related to the ability of the thread joints to resists the loads they are subjected to during operation. For that reason it is desired to provide threaded joints having the ability to better resists these loads and thereby give the components prolonged working life.
[0004] Another important aspect is producibility at low cost.
[0005] From U.S. Pat. No. 4,040,756 is previously known a threaded joint with inclined thread tops. When it concerns thread bottoms of the female as well as of the male thread, they are, however, provided with continuously curved configuration. The thread bottoms are going evenly, tangentially, over into adjacent thread flanks.
[0006] As further examples of the background art can be mentioned U.S. Pat. No. 6,196,598 and U.S. Pat. No. 4,687,368, whereof the latter concerns a more traditional trapezoidal thread.
THE AIM AND MOST IMPORTANT FEATURES OF THE INVENTION
[0007] It is an aim of the present invention to provide a further development of the devices according to the background art and to provide a device in a drill string component including a male thread as well as a drill string component and a method, wherein a resulting thread joint can be given greater resistibility to fatigue and thereby drilling can be performed with better economy.
[0008] These aims are obtained in respect of a device and a drill string component according to the above in that said thread bottom exhibits at least three surface portions with part-circular shape, as seen in an axial section, and that said surface portions with part-circular shape have increasing radiuses, as seen from each thread flank to an intermediate surface portion of the thread bottom.
[0009] Hereby is achieved that tension concentrations occurring in a most sensitive region of the thread, namely in connection to the root area of the pressure flank, will be widened and be levelled out as compared with the case of a conventional thread, irrespective if it concerns a trapezoidal type thread with partly linearly extending thread bottom or if it concerns a thread with evenly curved thread bottom.
[0010] According to the invention this is achieved in a thread that is economically advantages producible when the thread groove has an essentially equal shaped sectional shape along its extension and thereby can be produced with conventional production methods. Use of circular shapes of the surface portions results in simple and economically advantageous production. Determining the extension of the surface portions having part-circular shape in order to obtain the desired tension reducing effect can be made using conventional calculation methods.
[0011] It should be noted that a reduced tension concentration in this area of the thread bottom is very advantageous for the working life of the threaded joint, since already small reductions of the tension level in this area result in better resistibility to fatigue fractures and thereby thread failure.
[0012] Through the features of the invention it is achieved that the forces affecting the pressure flank, and to be received in the form of inner tensions in the material of the thread, will be received in a more advantageous way by the shape of the thread bottom being adapted for the reduction of forms that could increase tension concentrations. In particular it has unexpectedly been shown that the inventive construction results in extending tension distribution to at larger superficial portion of the thread bottom area and thereby reduced resulting maximal tension. In respect of the inventive construction, the surface portion having part-circular shape closest to the pressure flank is followed by a surface portion with greater radius or even with a plurality of surface portions having successively increasing radiuses, as seen in a direction towards an intermediate surface portion of the thread bottom.
[0013] A further advantage of the inventive construction compared to a conventional trapezoidal thread is that in a thread profile of a male thread according to the invention it will become easier to induce compressive stresses into the material through shot peening or through any other method that will plasticise material on a micro level, compared to the case in conventional threads. The reason for this is that accessibility for ejected shots will become better which leads to more even and more secure treatment of the thread.
[0014] Suitably said intermediate surface portion of the thread bottom is a central surface portion of the thread bottom.
[0015] It is preferred that said surface portions having part-circular shape are evenly passing over to one another and to an adjacent thread flank respectively. Hereby is intended that it exists tangential passages without tension inducing angles. It is preferred that they also pass directly over into each other without the intermediate or for example linear portions, since such passages do not contribute to tension level reduction.
[0016] Suitably a relation between a radius of a respective surface portion closest to a thread flank and a radius of a central surface portion of the thread bottom amounts to about 0.05-0.7, preferably to around 0.3-0.6, and most preferred to 0.35-0.55.
[0017] In one aspect of the invention, the thread groove, and in particular the thread bottom is asymmetrical as seen in said axial section. Asymmetric here means that the thread bottom as seen in the axial section lacks symmetry in respect of an imagined radial line (as indicated with interrupted line at L in FIG. 2 ) between two adjacent thread ridges.
[0018] Hereby the thread bottom suitably comprises such shape that a surface portion having part-circular shape adjoining to a thread flank, which is opposite to the pressure flank, extend more inwardly towards a symmetry axis of the drill string component than a surface portion with part-circular shape joining to a thread flank, which comprises the pressure flank. Preferably a thread flank being opposite to the pressure flank extends longer towards the symmetry axis of the drill string component than a thread flank forming the pressure flank does. A ratio between a radius of the surface portion having part-circular shape adjoining to the thread flank forming pressure flank and a radius of the surface portion having part-circular form adjoining to the thread flank being opposite to the pressure flank is thus in this embodiment greater than 1 and suitably between 1 and 10.
[0019] It is preferred that the thread flanks have linear extension as seen in an axial section of the drill string component.
[0020] In an embodiment of the invention, the thread is a conical thread, wherein a suitable cone angle of the conical thread is a cone angle of 2°-8°.
[0021] Preferably the thread bottom, at least in a surface area adjoining to a thread flank not being the pressure flank is constructed with such depth in respect of a height of a thread top of the thread that, in case of an angular deviation of a connected thread joint, contact is established between an adjacent thread top of the male thread and a thread bottom of the female thread whereby contact in said surface area adjoining to the second thread flank with a thread top of said female thread is avoided.
[0022] Hereby is achieved that the properties of the thread joint for drilling with obliquely deviating joint are enhanced.
[0023] In a non insignificant obliqueness resulting from relatively strongly curved drill holes, the risk of fatigue fracture of the threaded joint with loss of the drill string component into the drill hole as the result would otherwise increase.
[0024] Through this aspect is achieved that also in case of obliquely deviating thread joints, contact is avoided between the thread top of the female thread and a thread root portion of the male thread, whereby contact thus is avoided where the greatest tension concentration would have resulted. Such contact would otherwise lead to heating in the contact area, wherein the material would be unhardened and easily damaged which tends to bring about drawbacks with fatigue fractures of the male thread, since potential tension concentrations would occur in a highly unwanted position.
[0025] Through the invention is achieved that tension reduction and avoiding contacts in the bottom of the male thread according to the above in an advantageous manner can be combined, and in particular in respect of asymmetrically shaped thread grooves, the male thread can be shaped to satisfy principally different aims closest to the respective thread flank. Hereby the thread can be shaped such that a smallest cross section of the thread can be made greater compared to what would be the case according to the background art.
[0026] In a particularly preferred aspect, the thread is a male thread for threading together with a complementary female thread arranged on another drill string component. The thread is however, also advantageously a female thread for threading together with a complementary male thread arranged on another drill string component.
[0027] The invention also relates to a thread joint including a male thread and a female thread, wherein the thread joint is constructed with a device according to the above.
[0028] The invention further concerns a drill string component from the group: a drill bit, a drill rod, a joining sleeve, a shank adapter, which includes at least one device according to the above.
BRIEF DESCRIPTION OF DRAWINGS
[0029] The drawings show:
[0030] FIG. 1 diagrammatically different drill string components equipped with inventive devices,
[0031] FIG. 2 a part of an axel section through a thread joint,
[0032] FIG. 3 shows a detail of a thread joint according to FIG. 2 in an oblique condition,
[0033] FIG. 4 a is a computer simulation of a load situation and the figure shows a partial section through the inventive thread profile with indication of obtained tension distribution over the area of and below the thread bottom,
[0034] FIG. 4 b is also a computer simulation of a load situation and the figure shows a partial section through a conventional thread profile with indication of obtained tension distribution over the area of and under the tread bottom,
[0035] FIG. 5 shows in an axial section a conical thread joint according to the invention, and
[0036] FIGS. 6 a - c and 7 a - b show details of a thread according to the invention.
DESCRIPTION OF EMBODIMENTS
[0037] The group “drill string components”, being intended with this invention, includes drill bits, drill rods, shank adapters, joining sleeves and transfer adapters.
[0038] In FIG. 1 are shown different exemplary drill string components and parts thereof with devices according to the invention, namely:
[0000] a) A drill rod with a male thread as well as with a female thread.
b) A shank adapter with a male thread.
c) A part of a drill rod with a conical thread.
d) Parts of drill rods with a male thread and a female thread, respectively.
e) A drill bit with a female thread.
f) A joining sleeve with two female threads.
[0039] The thread joints are for threading together drill string components for percussive drilling. Inside the drill string components extends axially continuously a flushing channel for transfer of flushing flow to the drill bit.
[0040] In FIG. 2 is shown a detail of an inventive thread joint, wherein a first thread ridge 7 and a second thread ridge 7 ′ are shown belonging to the male thread. A thread ridge of the female thread is indicated with 8 . Between the thread ridges 7 and 7 ′ is positioned a thread groove 9 , that receives the thread ridge 8 in turn having an essentially equal sectional shape along its extension.
[0041] The thread groove 9 has a thread bottom 12 , exhibiting a plurality of surface portions having part-circular shape, which pass over into each other, namely a first surface portion Y 1 having a radius RA closest to a first thread flank 10 comprising pressure flank, a second surface portion Y 2 having a radius RC closest to a second thread flank 11 and an intermediate, here central, surface portion YC having a radius RB. The surface portions pass evenly, that is tangentially, over into each other. This is preferred, even if it can exist linear passages and also, which is not recommended uneven passages having angular steps between the surface portions. The treaded flanks form the same angle to a symmetry axis of the thread. Normally, this angle is 35°. In certain cases other angles can exist for example 45°.
[0042] The radius RB of the central surface portion YC is greater than both radiuses closest to the two thread flanks 10 and 11 . Suitably there is a ratio between RA respectively RC and RB of about 0.05-0.70, preferably of about 0.30-0.60, and most preferred of 0.35-0.55. Hereby the advantages are obtained relating to reduced tension levels that are presented in the above introductory part of the description.
[0043] In one aspect of the invention, the thread bottom 12 , in a surface area adjoining to the second thread flank 11 exhibits such a depth in respect of a height of the thread ridge 7 ′, that in the event of an oblique position of the threaded joint, contact is established first between the thread top of the thread ridge 7 ′ of the male thread with a thread bottom 13 of the female thread.
[0044] An imagined radial line between two adjacent thread walls is indicated with L. A smallest cross sectional radius with B. 6 indicates a flushing channel.
[0045] This is more evident in detail from FIG. 3 , wherein an oblique positioning has occurred between the female thread 3 and the male thread 2 . A central axis of the female thread is indicated with double-pointed line whereas a central axis of the male thread is indicated with a single-pointed line. The oblique position is in FIG. 3 exaggerated for clarity and is indicated with the angle α.
[0046] As is shown from FIG. 3 , contact has thus been established in the area 13 - 14 , which corresponds to contact having been reached by the thread top 14 of the male thread having come to contact with the thread bottom at 13 of the female thread. In the surface area indicated with 15 being the root area of the thread ridge of the male thread, at the second thread flank 7 ′, there is no contact between the thread top of the female thread and the thread bottom of the male thread, which results in that burning or pitting in this area is avoided, whereby thus is avoided the otherwise resulting above discussed heating of the area 15 , unhardening of the same and risk of fatigue damages to the male thread.
[0047] FIG. 4 a shows obtained tension distribution of the area of and below a thread bottom of a male thread 2 , which is screwed together with a not shown female thread. The figure shows a number of lines indicating the same tension, wherein the numerals (60%-85%) concerns percentage of the maximal tension which will occur in a comparative thread being a conventional trapezoidal thread according to FIG. 4 b . It should be noted that load distribution is the same for the two comparative objects in the FIGS. 4 a and 4 b.
[0048] As is evident from FIG. 4 a , the greatest tension concentration is localized to a superficial area relatively close to the pressure flank 10 . The maximal registered tension is somewhat over 85° of the maximal tension occurring in respect of the comparative thread. From the figure it is also evident that the tension is distributed over a great area and that the tension extends without jumps and unevennesses.
[0049] As is clear from FIG. 4 b , the greatest tension concentration is also here localized to a superficial area being relatively small and being relatively close to the pressure flank 10 . The maximal registered tension in respect of the comparative thread is of course by definition 100%. From the figure it is evident also that the tension is distributed in a smaller area.
[0050] A comparison between the results in FIGS. 4 a and 4 b reveals that the maximal tension in the root area of a thread according to the invention has been reduced with up to 12-15%. Further, it is evident that the tension distribution in respect of the conventional thread, in spite of the higher tension level, is more concentrated, which results in higher effect on the material during load.
[0051] This good result for a thread according to the invention is surprising and indicates at the considerable enhancement can be expected as concerns resistance to fatigue of the device according to the invention in comparison to the conventional thread.
[0052] In FIG. 5 is shown a conical thread according to the invention with a male thread 2 and a female thread 3 . Also in this embodiment the respective thread groove has an essentially equal sectional shape along its extension.
[0053] In FIG. 6 a is shown a detail of a thread groove with two surface portions having part-circular shape (with the respective radius RA and RB) passing evenly and directly over into each other. In FIG. 6 b is shown a detail of a thread groove having two surface portions with part-circular shape (with respective radius RA and RB) passing directly over into each other over a linear portion indicated with x. In FIG. 6 c is shown a detail of a thread groove having two surface portions with part-circular shape (with the respective radius RA and RC) passing unevenly over into each other, there is no tangential passage at the unfilled arrow.
[0054] In FIG. 7 a is shown a detail of a thread groove having a thread flank 10 and a surface portion with part-circular shape (with radius RA) passing evenly and directly over into each other. In FIG. 7 b is shown a detail of a thread groove having a thread flank 10 and a surface portion with part-circular shape (with radius RA) passing unevenly over into each other, that is no tangential passage at the unfilled arrow.
[0055] The present invention relates to drill string components for percussive rock drilling with contact surfaces between a male thread and a female thread, wherein particular and hard requirements on the behaviour of the thread is crucial for reliable function. Generally seen is intended that the present thread provides flank angles of 20°-50° and more preferred about 22.5°-47.5°. As is indicated above a usual value of the flank angle is 35° but other angle values are preferred in certain cases, for example 45°.
[0056] Because of the demanding conditions for devices according to the invention, drill string components for percussive rock drilling, the thread in question is relatively shallow having a relationship between (thread) profile height and (thread) profile width of 0.10-0.30, more preferred 0.20-0.30 and most preferred 0.23-0.25. With profile height is here intended the distance from the bottom of the thread (the thread groove) to the thread top, and with profile width is here intended the distance between the intersections of two straight lines extending in a central axial section along two adjacent thread flanks in a thread groove with a thread top line.
[0057] A ratio between profile height (see above) and pitch of the thread in an inventive device is generally 0.05-0.25 and more preferred 0.13-0.17.
[0058] The invention is adaptable in different types of drill string components and is particularly advantageous in respect of male threads, since in respect of these, tension concentrations are of particularly great importance for the working life, simple because of the construction of the male threads and their relative sensitivity to load. Female threads in sleeve forms can be shaped with greater inherent resistance to load.
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A device in a drill string component for percussive rock drilling including a thread for threading together with another drill string component including a complementary thread. The thread includes a thread groove formed by two thread flanks and an intermediate thread bottom. In operation one of the flanks forms a pressure flank. The thread groove has an essentially equally shaped sectional form along its axial extension. The thread bottom exhibits at least three surface portions with part-circular shape, as seen in an axial section. The surface portions with part-circular shape have increasing radiuses, as seen from each thread flank to an intermediate surface portion of the thread bottom. Also a thread joint and a drill string component.
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BACKGROUND
[0001] The technical field generally to which this application and the within-described invention applies relates to the protection of young or otherwise vulnerable plants growing outdoors naturally or in a planned garden or landscaped setting. Such plants, especially when in the form or developmental phase as seedlings, sprouts, “starts,” or as new transplants, are especially exposed to potential damage and destruction from various animals and insects, commonly referred to individually and/or collectively as “garden pests,” and are likewise susceptible to damaging effects from the more severe types of weather conditions and natural environmental elements that can occur or otherwise be present, such as high heat, intense sunlight, frost, heavy rain, falling or blowing debris, wind or hail. One of the main reasons young plants are so vulnerable to garden pests is that they can be especially tender and tasty during the above-referenced stages of development, and can provide a ready and desirable food source for garden pests that are able to gain access. The loss of and/or replacement of seedlings and other young or vulnerable plants destroyed or damaged by garden pests or natural-elements can be time-consuming, costly, dispiriting, and highly frustrating. There have heretofore been various attempts to fashion or create various implements, devices or other inventions to attempt to protect plants from these types of damages; however, many if not all of the current designs (whether or not presently commercially available) are bulky, cumbersome, costly, flimsy, heavy, ineffective, poorly designed or constructed, more appropriate for fully-developed plants rather than young plants, damaging or detrimental to plants in other unintended respects, and/or difficult to assemble, use, ship, transport, move about, and/or store. Therefore, further technological developments and inventions in this field which are not encumbered with such imperfections, limitations or difficulties are necessary and desirable.
SUMMARY
[0002] One embodiment of the present application includes a plant (in the botanical sense) protection apparatus. Other embodiments include unique plant protection apparatuses, systems, and methods. Further embodiments, inventions, forms, objects, features, advantages, aspects, and benefits of the present application are otherwise set forth or become apparent from the descriptions, drawings and illustrations included herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] The descriptions herein make reference to the accompanying drawings wherein like-referenced numerals refer to like parts, areas, placements, locations or physical positions throughout the several views, and wherein:
[0004] FIG. 1 is an illustrative embodiment of a plant protector, which can be assembled from various individual pieces, as described below, or made in one complete unit as a whole, as similarly described below.
[0005] FIG. 2 is an illustrative embodiment of a top panel or cover (also referred to as a “lid”) of a plant protector.
[0006] FIG. 3 is an illustrative embodiment of a side panel of a plant protector, with an attached, downwardly-protruding ground retention mechanism or member, also referred to as a “leg.”
[0007] FIG. 4 is a cut-away (enlarged, isolated) perspective of a portion of FIG. 3 (such portion being shown on FIG. 3 as 312 ), illustrating a tab and a tab receiving mechanism or member (also referred to as a “slot”).
[0008] FIG. 5 depicts an illustrative embodiment of a plurality of plant protectors in a collapsed or unassembled, stacked state.
[0009] FIG. 6 depicts an illustrative embodiment of a plurality of fully-assembled plant protectors in a stacked state (one inside the other).
[0010] FIG. 7 depicts an illustrative embodiment of a plurality of side panels as fully assembled and connected to one another to form an initial frame, but prior to the attachment thereto of a lid.
DETAILED DESCRIPTION
[0011] For purposes of promoting an understanding of the principles, design and utility of the within invention, reference(s) will now be made to the embodiments illustrated in the accompanying drawings, as well as to additional and separate embodiments which are not in fact illustrated in such drawings, and specific language will be used to describe the same. It will nevertheless be understood that no limitation or diminution of the scope of the invention is thereby intended, and that any alterations, enhancements and/or further modifications regarding the illustrated device or the various embodiments thereof as described herein, and any further applications of the principles of the invention as illustrated or described herein, are hereby deemed and declared expressly or impliedly contemplated and included therein and herein as would normally or obviously occur to one skilled in the art to which the invention relates.
[0012] FIG. 1 illustrates one particular embodiment of the present invention. A fully-assembled plant protector 100 forms an open-air and substantially open-to-sunlight and open-to-moisture enclosure which can be placed over a plant, such as a seedling, and securely anchored/attached to the ground by use of the attached legs 106 . The plant protector 100 can be utilized to provide protection to the plant from various animals, insects and other common garden pests, and can also be utilized to help shield the plant from intense sunlight and heat, heavy rains and downpours, wind, hail, supplemental frost-protection coverings, and blowing or falling debris. The fully-assembled plant protector enclosure 100 , as shown, is constructed of a plurality of side panels 102 and a lid 108 .
[0013] As is illustrated in FIGS. 1-3 , the side panels 102 and lid 108 include within the interior area of their respective outside boundaries a gridded mesh or screening portion 114 (hereinafter sometimes referred to simply as “mesh”). In some forms, each of the side panels 102 and lid 108 are almost entirely constructed of a mesh area 114 , as is shown in said illustrations. The additional non-mesh portions of the side panels and lid, including without limitation the somewhat thickened members 305 , 314 , 118 , 320 , 201 (also referred to herein as “sides,” “top rails” “bottom rails,” “edges” and/or “perimeters”) located along the outside perimeters of the side panel 102 and lid 108 , can be used: (a) to assist in the manufacturing process 202 , 202 a , 204 , 204 a , (b) to provide support, strength, bracing and rigidity 305 , 314 , 118 , 320 , 201 to the overall enclosure 100 , (c) to connect and attach the plurality of pieces to one another 208 , 310 in order to form the overall plant protector enclosure 100 , (d) to anchor and secure the overall structure to the ground 106 , and (e) to provide an area for use in product marketing, trademark or patent status disclosure, and promotion 106 a , 204 .
[0014] The incorporation and use of the mesh construction 114 within the interior areas of the side panels 102 and lid 108 permits the plant protector 100 to provide protection to the plant from garden pests, while still allowing sufficient air, sunlight and moisture to freely penetrate the enclosure to provide nutrients and other natural elements necessary for the health and vigor of the growing plant enclosed by the plant protector 100 . The mesh 114 can take or implement a variety of forms, thicknesses, dimensions, shapes, patterns, and spacings depending on the desired design and specific application of the user, as would be known or obvious to one of ordinary skill in the art.
[0015] As mentioned, the meshed side panels and lid 102 and 108 can also include thickened members along their respective outside edges 305 , 314 , 118 , 320 , 201 to provide for a rigid and strengthened construction (the ultimate thicknesses, dimensions and particular shapes for which can provide an array of differing levels of rigidity and strength, as desired by the user). In addition, the bottom rails 118 of the side panels 102 , when fully assembled as shown in FIGS. 1 and 7 , will provide a firm, ground-level base of support for the plant protector 100 when in use. The rigidity of the illustrated side panels 102 and lid 108 is such that, when they are connected and attached together to form the plant protector 100 , the overall plant protector 100 becomes a unified, integrally-connected structure that is self-supporting and self-bracing, the strength and rigidity of which is made especially more so when the slightly-angled legs 106 are properly and fully positioned in the ground.
[0016] As would be understood by or obvious to one of ordinary skill in the art, the desired overall rigidity, size, shape, weight, mesh opening sizes, and ultimate specific design of the side panels and lid 102 and 108 , including without limitation the size, length, thickness and angle of the attached legs 106 , can depend upon individual user requirements or desires, including, but not limited to, in the first instance: (a) the size, foraging habits, prevalence, sensory capabilities, aggressiveness, physical strength and capabilities, mobility, ambulatory capabilities, and specific type(s) of garden pests desired to be excluded and against which protection is sought, and (b) the type, prevalence and intensity of local weather conditions and other natural outdoor environmental elements from which protection is sought. Additionally, the overall size and design of the side panels 102 and lid 108 , and of the mesh 114 , can depend upon, in the second instance: (a) the size, number and/or spacing of the seedling(s) or plant(s) desired to be protected by the plant protector 100 at the time the plant protector 100 is first applied, (b) the horticultural needs, ongoing vulnerability, and growth characteristics of the plant during the time it is expected to remain protected within the enclosure, and (c) the overall anticipated height and girth of the plant at the time the user expects to remove the plant protector 100 from continued use; all as would be known or obvious to one of ordinary skill in the art.
[0017] The side panels 102 and lid 108 , as well as the overall plant protector 100 , can be constructed and/or manufactured utilizing a variety of techniques, methods and materials in order to obtain the utility for which they and it are designed and intended. It is contemplated, for example, that the side panels 102 and lid 108 can be constructed of one or more pieces of metal (and of one or more types of metal) through, for example, a stamping, pressing, cutting, molding and/or folding process or other forming techniques as would be understood by one of ordinary skill in the art. In another form, it is contemplated that the side panels 102 and lid 108 , as well as the overall plant protector 100 , can be constructed of a polymer such as plastic or resin, whether in one piece or from a plurality of individual and separate pieces. In one specific embodiment, as detailed and illustrated in this application, the side panels 102 and lid 108 are formed via plastic injection molding. However, it should be appreciated that other materials and forming and construction techniques suitable to yield the side panels 102 and lid 108 , as well as the overall plant protector 100 , are herein contemplated within the scope of the present invention, as would be known or obvious to one of ordinary skill in the art.
[0018] FIGS. 2 and 3 illustrate one embodiment of a side panel 102 and one embodiment of a lid 108 , respectively, each formed of injection molded plastic. An injection site (injection point) 204 , 204 a is illustrated for each piece, where molten plastic is injected into a mold to spread throughout and fill a pre-formed cavity within the mold. Although the injection points 204 and 204 a are illustrated in FIGS. 2 and 3 , respectively, as having a square shape and as centrally located within the respective mesh 114 areas, the injection points 204 and 204 a could also be of a different size or shape, and could be positioned at another location within or leading to the respective mold cavities of the side panel 102 and lid 108 . A plurality of ejection pin points 202 , 202 a can be disposed throughout the mesh portions 114 in the side panels and lids 102 , 108 , at various intersection points of the mesh 114 and in a variety of patterns and/or spacing. These ejection pin points 202 , 202 a allow for and assist with the ejection of the respective injection-molded pieces from the respective molds after the polymer has at least partially set. As can be appreciated, the ultimate location, size, shape and number of ejection pin points 202 , 202 a can depend on various design and specific manufacturing aspects that are selected or desired, including but not limited to, the type of polymer used (including any additives) and the physical characteristics thereof, the strength, size and spacing of the formed mesh, as well as the overall dimensions of the desired plant protector 100 .
[0019] Referencing FIG. 3 , and as mentioned above, one embodiment of a representative side panel 102 formed of injection molded plastic is illustrated. As shown, the width (horizontal distance) 306 of the top rail 305 of the side panel 102 is less than and centered-symmetrical to the width (horizontal distance) 308 of the bottom rail 118 of the side panel 102 , thereby creating an angle away from vertical when moving from one of the far ends of the top rail to the opposing far end of the bottom rail along the outside edges of the side panel 102 , and thereby giving the side panel 102 an overall trapezoidal shape. See FIG. 3 .
[0020] The smaller width 306 of the top rail 305 relative to the larger width 308 of the bottom rail 118 , i.e., the trapezoidal shape of the side panel 102 , permits a plurality of plant protectors 100 , once assembled, to be stacked one on top of and/or one inside of the other for more efficient storage and transport of the plant protectors 100 when not in use. See, e.g., FIG. 6 . This is because the trapezoidal shape of the side panel 102 , when attached to and connected with a plurality of additional side panels 102 in the manner illustrated, will create an overall “flat-topped” 4-sided pyramidal shape. See, e.g., FIGS. 1, 6 and 7 . Referring to FIGS. 1 and 6 , the square, top portion 108 of one plant protector 100 can be placed within the square, open-air bottom base area 118 a (defined by the plurality of bottom rails 118 of the connected plurality of side panels 102 ) of a second plant protector 100 , such that the first plant protector 100 , when pushed or placed completely into the open-air interior space of the second plant protector 100 , will fit symmetrically within said space, and will securely nest within the second plant protector 100 . See FIG. 6 . As mentioned, this nesting and stacking capability of a plurality of plant protectors 100 will allow for ease of storage, transport and/or shipping of said plurality when not in use. In addition to the benefits obtained from the aforementioned symmetrical stacking capability, the trapezoidal shape of the side panels 102 , when fully assembled with a plurality of other side panels 102 and a lid 108 into a complete plant protector 100 , also creates an angle away from vertical for the legs 106 when placed into the ground, thereby increasing the strength and resistance capabilities of the overall plant protector 100 when and if lateral forces are applied thereto (i.e., it will be more difficult for a garden pest animal to lift it from the ground, knock it over, or pull it over).
[0021] It must be stated, however, that the respective trapezoidal and flat-topped pyramidal shapes of the side panel 102 and the overall plant protector 100 as illustrated in this application are not required for the overall utility and/or functionality of the invention. Rather, different shapes and sizes of the side panels 102 and of the overall plant protector 100 may be implemented and used in an unlimited variety of additional embodiments, including as an example but without limitation, by using square-shaped or rectangular-shaped side panels 102 , which if implemented and assembled into an overall design would thereby create a cube-shaped or box-shaped structure for the overall plant protector 100 . As a result of the particular embodiment used as an example, square-, rectangular-, cubed- or box-shaped plant protectors 100 would not be able to fit one inside the other unless they were of different overall shapes and/or sizes.
[0022] Furthermore, the plant protector 100 does not need to include any built-in legs 106 or other ground retention devices in order to retain the basic utility or functionality intended for the overall invention. Although it would likely provide less security if larger or stronger types of garden pests were present, an embodiment of the plant protector 100 without built-in ground retention devices would nevertheless provide some level of protection from smaller garden pests (and from the elements) even if used without such built-in ground retention devices. Additionally, an embodiment of the plant protector 100 without built-in ground retention devices could provide substantial protection from garden pests and from the elements if alternative or supplemental ground retention devices, such as “j-hooks,” tent-type stakes or weighted items, were used to help hold the plant protector 100 in place.
[0023] However, the plant protector 100 will provide the most favorable and dependable protections, as well as ease of use, if at least one or a plurality of ground retention devices or members, such as the illustrated legs 106 , are built-in and integrated to the plant protector 100 . The embodiment of the plant protector 100 as depicted in this application includes such built-in ground retention members or “legs” 106 . See FIGS. 1 and 3 . The leg 106 extends downwardly from the base or bottom rail 118 of at least one of the side panels 102 . It can so extend downwardly from any point along the horizontal base rail 118 of the side panel 102 . In one form, as shown in FIGS. 1 and 3 , each side panel 102 can include a leg or ground retention member 106 that extends downwardly from the center point of the horizontal base rail 118 of the side panel 102 . Using such center point for the attachment and downward extension of the leg 106 allows the user of the plant protector 100 to apply the maximum amount of downward force and pressure to the overall structure in order to properly seat the legs 106 into the ground when initially used and positioned above the plant to be protected. If the user finds the ground to be dry or compacted when attempting to place the plant protector 100 , however, the user is advised to first make small pilot holes in the ground at the spot of each leg tip 106 , using a pointed hand tool, so as to allow the legs 106 to more easily penetrate into the ground and to avoid putting undue pressure thereon. In fact, using such center point of the bottom rail 118 of the side panel 102 for the point of attachment and downward extension of the leg 106 also allows the assembler of the plant protector 100 to gain substantial increased support for the base of the plant protector 100 during the assembly process, and especially at the point in such process when the lid 108 is attached to the frame of the plurality of side panels 102 , as more particularly discussed below.
[0024] The ground retention member (or leg) 106 , as its descriptive name implies, is structured and designed to hold the overall plant protection enclosure 100 securely to the ground. Retaining the plant protection enclosure 100 securely to the ground will prevent movement of the plant protector 100 relative to the protected plant within the interior, thereby avoiding potential damage to the plant from undue contact with the plant protector 100 , and secure retention can also prevent or deter animal garden pests from lifting or pulling on the plant protector 100 in an attempt to knock it over or to enter the enclosure. The specific design, shape, length and size of the ground retention member 106 can take a variety of forms, including, but not limited to a ground retention member in the general shape of a tine, stake, spear-head or arrowhead, pointed or barbed peg, or any other spiked-type shape, such that the ground retention member 106 can aid in the holding of the plant protector 100 securely to the ground.
[0025] Referring to FIGS. 1-3 , the plurality of side panels 102 are connected together such that an interior boundaried area, the “base” area, 118 a , is formed along and within the plurality of horizontal bottom rails 118 of the plurality of the side panels 102 . This boundaried base area 118 a defines the anticipated “ground-level” portion of the interior of the plant protection enclosure 100 as bounded by the horizontal bottom rails 118 of the plurality of connected side panels 102 . The plurality of connected side panels 102 and the lid 108 (including the mesh 114 incorporated within same), when all properly attached to one another and properly secured to the ground with the legs 106 , can prevent entrance to the interior of the plant protector enclosure 100 by a variety of common animal and insect garden pests, whether such entry is attempted through the sides or from the top of the plant protector enclosure 100 or from immediately underneath the horizontal bottom rails 118 of the side panels 102 . Additionally, the side panels 102 act as integrated structural support for the overall plant protector 100 .
[0026] A top panel, covering or “lid” 108 may or may not be used with the plant protector 100 as framed by a plurality of side panels 102 . See FIG. 7 . If the user elects to forego the use of a lid 108 , the user will retain free and ready access to the interior of the plant protector 100 from above. Having such access could benefit or assist the user for purposes of ease of watering, fertilizing, weeding, thinning, mulching, pruning or providing other general plant maintenance or care to the plant being protected within the enclosure. However, electing to forego the use of a lid 108 would also allow free and ready access to the interior of the plant protector 100 from above by any garden pest capable of reaching, climbing to, crawling to, jumping to, or flying to the open top of the plant protector 100 , which would likely be an unacceptable risk or otherwise undesirable to the user, as well as a significant departure from and a detriment to the overall protections designed to be afforded by the plant protector 100 . Furthermore, an election to forego the use of a lid 108 would significantly limit the ability of the plant protector 100 to help shield the protected plant from the more severe elements, as it is designed to do, such as from intense sunshine or heat, heavy rains, wind, hail, or falling debris. Finally, an election to forego the use of a lid 108 could make it more difficult to gently and evenly push the legs 106 of the plant protector 100 into the ground.
[0027] As well, the user could elect to use the lid 108 or any other similarly-shaped or adapted covering device as an easily removable, unattached cover for the plant protector 100 as framed by a plurality of side panels 102 , accomplishing such characteristics simply by forgoing the use of any attachment device or system for the lid, such as by electing not to use the built-in tab 310 and slot 208 attachment system that has been designed and incorporated into the side panels 102 and the lid 108 as shown in the embodiments depicted in this application. Such application and use of an unattached yet covering lid 108 would also provide the user with free and ready access to the interior of the plant protector 100 from above by simply removing the lid cover 108 temporarily, and would provide some level of shielding from the more extreme elements as mentioned above, but would nonetheless and in any event be more susceptible of being removed, displaced, lifted, or knocked away by larger, stronger or more aggressive or determined garden pests.
[0028] More robust and dependable protective capabilities can be enjoyed by the overall plant protector 100 by securely attaching the lid 108 to the frame of the assembled side panels 102 at a point on or along the length of at least one of the top horizontal rails 305 of at least one of the side panels 102 . Such a “one-sided” attachment scheme can be accomplished by any practical method, such as by using supplemental wire ties or removable clips, by use of a hinge or hinges, or by use of other common types of attachment or clamping devices, and thereafter, depending upon the attachment method so used, the user could enjoy both ready and free access to the interior of the plant protector 100 from above (for the purposes identified above), and the plant protector 100 with a one-sided attached lid 108 would provide a much enhanced level of protection from access by garden pests and for shielding the plant from the more extreme elements (likewise as identified above).
[0029] The strongest and most dependable protective capabilities of the plant protector 100 , however, can be achieved by securely attaching the lid 108 to the frame of the assembled plurality of side panels 102 at at least two oppositely-facing points along at least two of the top horizontal rails 305 of at least two of the side panels 102 . For example, but without limitation, such secure, opposing attachments of the lid 108 to the side panels 102 could be made (a) at one of the top corners of the overall structure 109 where a corner of the lid 108 meets the top of the connected corner of two of the side panels 102 , and then also at the opposite top cross-corner 109 a , or (b) at the central point 105 a of one horizontal top rail 305 of one side panel 102 and then also at the central point 105 b of the horizontal top rail 305 of the opposing side panel 102 . As mentioned, by securely attaching the lid 108 to the frame of the assembled plurality of side panels 102 at at least two points, the user gains the benefit of the strongest and most dependable protective capabilities of the plant protector 100 , yet loses the ability to gain free and ready access to the interior of the plant protector 100 to perform such gardening tasks as weeding, thinning, mulching or pruning (while watering and fertilizing tasks can typically still be accomplished with the lid 108 in place). Such loss of ready access can be easily overcome, however, simply by temporarily removing the plant protector enclosure 100 from the ground, performing the tasks desired with respect to the protected plant and/or the interior base area 118 a (such as weeding, thinning or pruning), and then replacing the plant protector 100 as it was prior to the temporary removal.
[0030] In one form as embodied in the depictions and illustrations herein, the entire perimeter portion 206 of the lid 108 can be easily, fully and securely attached and connected to the top horizontal rails 305 of each of the side panels 102 , by use of a built-in tab 310 and slot 208 attachment system that has been designed and incorporated directly into the side panels 102 and the lid 108 as integral, polymeric parts thereof, without the need to use any additional or supplemental parts or connecting devices, and without the need to use any tools during the assembly process, all as is illustrated in FIGS. 1-4 . The complete connection of the lid 108 to the frame of the plurality of side panels 102 by use of all eight pairings of the applicable tabs 310 and slots 208 yields a fully-assembled, freestanding, and ready-to-use plant protector 100 . See FIG. 1 . Maximum overall rigidity, shape- and form-retention capabilities, self-supporting capabilities, protective capabilities, and overall strength of the structure is attained through actual use thereof, when the plurality of legs 106 of the plant protector 100 are evenly, fully and securely placed into the ground.
[0031] In one form, the plant protector 100 is fully comprised as a unitary, one-piece structure that does not require further assembly or the use of supplemental parts, pieces or devices to obtain the overall design, i.e., it is comprised as a single complete unit ready for use. For example, but without limitation, and as would be known or obvious to one of normal skill in the art, with relatively slight engineering and technical modifications, revisions and/or enhancements, the individual configurations of the two separate mold cavities contemplated for use to manufacture the side panels 102 and the lid 108 as depicted herein by plastic injection molding, see FIGS. 1-3 , could be combined and attached seamlessly to one another along the various lengths of the current attachment points through further and fairly simple CAD procedures to create a single cavity for a unitary, one piece, polymeric structure. In other words, the overall shape and design of the plant protector structure 100 , as embodied in FIG. 1 , could be easily re-drawn and re-engineered as a single unit rather than a multi-pieced enclosure assembled from a plurality of interlocking individual parts, and could be easily manufactured with a single larger mold, rather than two separate smaller molds. In addition, it should be understood that a variety of production and manufacturing processes, methods, materials and techniques can be utilized to yield a unitary one-piece plant protector 100 , for example, but without limitation, by using metal or wire, screened or woven mesh, ceramics or glass, or any other malleable and structurally sound materials, and/or by using a process of bending, welding, stamping, pressing, molding, stapling, cutting, folding and/or any other commonly-known methods of shaping or forming such materials.
[0032] The form, design and method of attachment of the side panels 102 to one another, and of the lid 108 to the frame of a plurality of side panels 102 , as embodied in the illustrations herein, and as described herein by reference to the built-in tab 310 and slot 208 integrated attachment system, is specifically designed and intended to create a “locking” feature or characteristic with respect to said system, so that, when a tab 310 is fully inserted into a slot 208 , the head of the tab 310 , being slightly thicker than the width of the slot 208 , may pass through the slot 208 only with some small amount of straight-ahead or linear directional force and pressure being applied to the tab 310 , and so that, once the head of the tab 310 is pushed fully through the slot 208 , the head of the tab 310 , after it emerges from the far side of the slot 208 , will “lock” into place in a secure fashion, and whereby an effort to thereafter extract or remove the tab 310 from the slot 208 would be difficult at best, and in fact could require the use of a specialized leveraging or prying-type tool, as well as the need for specialized skill, to un-do or de-construct the original connection. In other words, the fully-assembled plant protector 100 , in the form described and illustrated herein, see FIG. 1 , is specifically intended and designed to be difficult to take apart by hand and/or to otherwise “collapse” it back into its individual plurality of pieces once it has been properly assembled and all of the plurality of pieces are properly connected. This “locking” feature of the tabs 310 and slots 208 provides added strength and rigidity to the overall plant protector enclosure 100 , and gives added assurance to the user that the plant protector 100 , when in use, will retain its shape and overall structural integrity even if small levels of external lateral forces are applied, and therefore the plant protector 100 will be made much more difficult to breach by an animal garden pest attempting to gain access. A final benefit of the “locking” feature makes it less likely that de-constructed individual pieces would be lost, misplaced or damaged when not in use.
[0033] In another form, the design and function of the attachment system to be used for the assembly of the plant protector 100 is such that the frame of the plurality of side panels 102 and the lid 108 , once fully assembled and connected to one another, are more easily severable and retractable from one another, i.e., by not requiring the use of any special tool or skill, and as a result the overall structure can easily be collapsed back into the several individual and distinct plurality of pieces as existed at the beginning of the initial assembly process, and therefore which can be selectively coupled and decoupled at the will and desire of the user.
[0034] Referring to FIGS. 1-4 , in one form the plurality of side panels 102 are attached to one another through a plurality of tabs 310 extending outward from the left-side edge 320 of each side panel 102 , and a plurality of tab receiving members, or “slots” 208 , are integrally positioned at identical but opposing locations along the right-side edge 314 of the side panel 102 . See FIG. 3 . To begin the assembly process, the user selects a “first” side panel 102 (shown as 116 in FIG. 1 ), and inserts the tabs 310 protruding from the left side edge 320 into and through the corresponding slots 208 of a “second” side panel 102 (shown as 110 in FIG. 1 ) until all of the plurality of tabs 310 of the first side panel 102 are fully engaged within and pushed through the plurality of corresponding slots 208 of the second side panel 102 , thereby creating a fully assembled “corner” or “combined-corner rail” 125 with respect to the two just-connected side panels 102 . The aforementioned assembly steps are then similarly repeated for the third and fourth side panels 102 , and then also and finally with respect to the plurality of tabs 310 of the first side panel 102 being inserted into the plurality of corresponding slots 208 of the fourth side panel 102 , thereby completing the 4-sided structural frame for the plant protector 100 . See FIG. 7 .
[0035] It should be noted here that a tab receiving member or slot 208 can take a variety of forms, shapes and sizes, such that the resulting aperture associated therewith can be structured to engage fully and securely with an inserted tab 310 , thereby making it difficult to remove, or it can be structured to engage fully yet more loosely with an inserted tab 310 , thereby making the tab 310 relatively easy to remove or retract from the slot 208 if desired by the user. The benefits and detractions of both of such attachment methods, and/or as may result from any compromise between or combination of the two, are as described hereinabove.
[0036] Referring to FIGS. 1-4 and 7 , in one form the lid 108 is attached to the frame of a plurality of previously-attached and assembled side panels 102 by use of a plurality of tabs 310 extending upward from the top horizontal rail 305 of each side panel 102 , and by using a plurality of tab receiving members, or “slots” 208 , that are integrally positioned at corresponding pre-determined locations along the outside perimeter 206 of the lid 108 . See FIGS. 1-4 and 7 . To begin the process of attaching the lid 108 to the frame of a plurality of previously-attached and assembled side panels 102 (see FIG. 7 ), the assembler/user selects one of the corners 205 of the lid 108 , and carefully positions the two slots 208 associated with that corner 205 directly above the two corresponding tabs 310 extending upward from each side of the top of the attached corner 707 created by two of the assembled side panels 102 making a part of the overall frame 125 . See FIG. 7 . When properly aligned and positioned, the two slots 208 of the selected lid corner 205 are gently pushed down and onto the heads of the two tabs 310 below 707 , and with further gentle downward force (while at the same time also giving support to the corner 111 of the side panel 102 base so as not to put undue pressure on the legs 106 ), the tabs 310 of said side panels 102 are caused to pass fully through said slots 208 , thereby engaging them and “locking” them into place 109 . This procedure is then repeated sequentially for the other three corners 205 of the lid 108 with respect to the other three corresponding pairs of tabs 310 extending upwards from the other three top corners 707 of the assembled side panel 102 frame, as a result of which, when completed, the lid 108 will be fully secured and attached to the frame of the plurality of assembled side panels 102 around the entire perimeter 206 of the lid 108 , and the plant protector 100 is now ready for use. See FIG. 1 .
[0037] In one specific embodiment of the plant protector 100 , the top horizontal rail 305 of a side panel 102 can include at least one or a plurality of tabs 310 extending upwards from said top rail 305 , and similarly each side edge 201 of a corresponding lid 108 to be subsequently attached thereto can include at least one or a plurality of tab receiving members or slots 208 . Similarly, a side panel 102 can include at least one or a plurality of tabs 310 extending outward from the left-side edge 320 of the side panel 102 , and can include at least one or a plurality of corresponding and similarly-aligned slots 208 on the opposing, right-side edge 314 of the side panel 102 . In another form, as depicted and illustrated herein: (a) each side panel 102 can include: (i) three tabs 310 extending outwardly from the left-side edge 320 of the side panel 102 , and three similarly-aligned tab receiving members or slots 208 integrated within the right-side edge 314 of the side panel 102 , and (ii) two tabs 310 extending upwardly from the top rail 305 of the side panel 102 , and (b) each lid 108 can include two properly-aligned slots 208 on each side of the perimeter 206 of the lid 108 , so that the lid 108 can be fully attached to the corresponding side panels 102 and tabs 310 thereof. See FIGS. 1-3 .
[0038] It should be understood and noted that while certain specified tab 310 and slot 208 placements, numbers, and alignments have been particularly described for specific embodiments as referenced herein, the invention is not limited to or restricted by these particular or specific tab 310 and slot 208 placements, numbers and/or alignments as so described. Rather, any combination or number or plurality of tabs 310 and tab receiving members 208 , and any variety, combination or alternatives of placements and/or alignments thereof in a final design, is expressly contemplated as being within the scope of the invention herein described, such that any such combination, number, plurality, variety or alternative with respect to the tabs 310 and slots 208 can ultimately be implemented in any design so as to cooperate with one another in order to assemble and connect the side panels 102 to one another and also to connect a frame of the assembled plurality of side panels 102 to the lid 108 .
[0039] As was previously discussed, in one form the lid 108 and the side panels 102 can be decoupled from one another and collapsed into individual pieces. As well, when a plant protector 100 is first being assembled from a plurality of individual pieces, those pieces are first obtained by the assembler/user as individual, decoupled, separate pieces. FIG. 5 illustrates a plurality of decoupled and stacked side panels 102 and lids 108 . In fact, this FIG. 5 also illustrates a stacked plurality of individual side panels 102 and individual lids 108 as they might appear immediately after being manufactured, and prior to any assembly procedures being undertaken. The capability of side panels 102 and lids 108 to be symmetrically and evenly stacked one on top of another while retaining a relatively low profile, whether done immediately after manufacture or whether done as a result of decoupling after a prior assembly, can provide ease of shipping, transport and storage. One example 502 of such a storage or shipping configuration, but without limitation, is as illustrated in FIG. 5 , therein showing an assembled configuration of side panels 102 and lids 108 sufficient to construct ten separate plant protectors 100 . As one of ordinary skill in the art can appreciate, any number or variety of possible stacking, shipping and/or storage configurations can be contemplated, depending upon the number of side panels 102 and/or lids 108 that are desired to be stacked, shipped and/or stored. In addition, one of ordinary skill in the art can likewise appreciate that the plurality of individual pieces of a collapsed and/or stacked plant protector 100 will take up much less overall space than a fully-assembled plant protector 100 . Cf., FIGS. 1, 5 and 6 .
[0040] While the invention herein has been described in connection with what is presently considered to be the most practical and preferred embodiment(s), it is to be understood that the invention is not to be limited to the disclosed embodiment(s), but on the contrary, is intended to cover various modifications and equivalent arrangements and structures included within the spirit and scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent arrangements and structures as permitted under the law. Furthermore, it should be understood that while the use of the word preferable, preferably, or preferred in the description above indicates that the feature so described may be more desirable, it nonetheless may not be necessary to achieve the intended and desired functionality and utility of the invention, and any further or separate embodiment lacking the same shall therefore be contemplated as within the scope of the invention, that scope being defined by the claims that follow.
[0041] In reading and reviewing the foregoing descriptions, it is intended that when words or phrases such as “a,” “an,” “at least one” and/or “at least a portion” are used therein, there is no intention to limit the description to only one item or subject matter unless specifically stated to the contrary in the description. Further, when the phrases “at least a portion” and/or “a portion” are used in a description, the item or subject matter being referenced may include a portion and/or the entire item or subject matter, unless specifically stated to the contrary. Finally, when reference is made within a description to “a plant,” “the plant,” and/or “the protected plant,” such references shall be deemed to mean a plant in the botanical sense, and shall also be deemed to include a plurality of plants, such as “plants,” “the plants,” and/or “the protected plants.”
[0042] Further, in reading and reviewing the claims that follow, it is intended that when words or phrases such as “a,” “an,” “at least one” and/or “at least a portion” are used within a claim, there is no intention to limit the claim to only one item or subject matter unless specifically stated to the contrary in the claim. Further, when the phrases “at least a portion” and/or “a portion” are used in stating a claim, the item or subject matter being referenced may include a portion and/or the entire item or subject matter unless specifically stated to the contrary. Finally, if a claim makes reference to “a plant,” “the plant,” and/or “the protected plant,” such references shall be deemed to mean a plant in the botanical sense, and shall also be deemed to include a plurality of plants, such as “plants,” “the plants,” and/or “the protected plants.”
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A plant protection apparatus includes a plurality of side panels. Each of the plurality of side panels includes a mesh portion and a width of each side panel is greater at a lower portion of the side panel than a width of each side panel at an upper portion of the side panel. A side portion of each side panel is operably connected to a side portion of another of the plurality of side panels thereby defining a boundaried area. A lid includes a mesh portion and a perimeter portion of the lid is operably connected to the upper portion of each side panel to yield a self-supporting plant enclosure.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Provisional application: U.S. Ser. No. 61/843,479
[0002] Filing date: Domestic Jul. 8, 2013
Foreign Jul. 17, 2013
FEDERAL SPONSORED RESEARCH OR DEVELOPMENT
[0004] “Not Applicable”
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM COMPACT DISC APPENDIX
[0005] “Not Applicable”
BACKGROUND OF THE INVENTION
[0006] Reloading of the tubular magazine of the (Marlin Model 60) semi-automatic 0.22 long rifle caliber, rifle has been historically slow. In order to comply with Marlin's only recommended loading procedure, rounds must be loaded into the tubular magazine loading port, FIG. 1 (a). Rigid plastic speed loaders existing prior to my invention, due to their rigidity are unwieldy and make it impossible to use the loading port. My speed loader is flexible and readily controllable allowing for a very safe, rapid, and controlled loading process using the loading port.
[0007] Being transparent it also allows the loader to ensure that the rounds are being loaded correctly preventing a misfeed. My speed loader can also be easily modified, by the purchaser, to conform to smaller round capacity, if required by a particular state law.
BRIEF SUMMARY OF THE INVENTION
[0008] Object of the speed loader is to allow for safe controlled rapid reloading of the (Marlin Model 60) semi automatic 0.22 long rifle caliber rifle via the loading port, FIG. 1 (a) on the rifle's tubular magazine. The speed loader is flexible so that it can be readily aligned to the tubular magazine loading port prior to the loading. It is clear so that the person loading can see that the rounds are being safely loaded bottom first preventing a misfeed. It can be modified to hold exactly the right number of rounds conforming to the magazine capacity of the rifle and to any state laws that may apply.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0009] FIG. 1 Shows the loading port on the tubular magazine. (The only manufacturer's recommended method of loading).
[0010] FIG. 2 Shows the components of the speed loader. (Loaded with cartridges).
[0011] FIG. 3 Shows the cartridges being loaded into the loading port via the speed loader.
DETAILED DESCRIPTION OF THE INVENTION
[0012] This newly invented, speed loader is manufactured with 3 components, FIG. 2 ).
[0013] First, (a) the tube which houses the cartridges, is flexible, weather proof, clear vinyl ( 5/16) inches inside diameter and ( 7/16) inches outside diameter, (the tube is cut to the desired length to accommodate the desired magazine load capacity) second (b), the nylon hole plug ( 5/16) inches in diameter (which seals one end of the open tube), is attached with super glue, lastly (c) the rubber stopper which is ( 5/16) inches in diameter on its smaller end seals the other end of the tube, this is the end that the speed loader is loaded and unloaded from. The rubber stopper is used to seal the tube after the cartridges are loaded. FIG. 3 , (b) the Marlin Model 60 tube magazine with a cartridge loading port (which is cut into the rifle's tube magazine) that ensures that cartridges are loaded safely bottom down ensuring proper loading into the breech, however that makes loading slow and tedious. My design is simply, more weather proof due to all plastic construction, easier to control due to its flexibility, and safer. Because of the unrestricted visibility into the speed loader, it is easy to verify that the speed loader is loaded with the cartridges bottom down so that when loading there are no miss feeds, therefore no chance of a jam. To load the speed loader, (first) remove the rubber stopper FIG. 2 (c), (second) load the cartridges into the tube (a) nose first (this will ensure that when you load the rifle's tube magazine the cartridges will be loaded into the magazine bottom first). (Third), seal the speed loader with the rubber stopper (c). (Fourth), verify visually that each cartridge is properly loaded nose first and that the bottom of the cartridges are facing the rubber stopper.
[0014] To load the Marlin Model 60 FIG. 3 , holding the rifle upright at a slight angle , rifle butt on the ground, remove the rubber stopper (c)of the speed loader pinching the opened end (with your fingers) where the stopper was, to keep the cartridges from coming out, (third) align the speed loader to the rifle's opened loading port (b) in the tubular magazine, when aligned relax the pinched tube and the cartridges will flow into the magazine.
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This invention, conforms to Marlin's (the manufacturer) only recommended loading method, utilizing the magazine loading port. It can be easily modified by the purchaser to conform to any laws limiting magazine round capacity.
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FIELD OF THE INVENTION
The present invention relates to: microspheres having a mean diameter ≧0.1 and <1 μ, comprising a biocompatible polysaccharide polymer and optionally at least one active ingredient, pharmaceutical compositions containing said microspheres administrable by oral, nasal, pulmonary, vaginal or rectal route, the use of microspheres having a mean diameter ranging from 0.1 to 1 μ as carriers for the preparation of pharmaceutical compositions for human genic therapy, for the preparation of diagnostics and in the agroalimentary industry, a process for the preparation of microspheres having a mean dimension of between 0,1 and 1 μ comprising the precipitation of said polymer induced by means of a supercritical antisolvent (SAS).
TECHNOLOGICAL BACKGROUND
Major advances have recently been made in pharmaceutical technology to research new methods for the preservation of the intrinsic activity of polypeptides and to render them absorbent. Formulations able to ensure a reproducible absorption of these active molecules have the advantage of lacking side effects, unlike synthetic polymers. Of all the most widely used natural polymers, the category of acidic polysaccharides is of particular interest. One of these, hyaluronic acid, a polysaccharide widely distributed throughout animal organisms, is constituted by units of D-glucuronic acid and N-acetyl D-glucosamine in alternate order. Its molecular weight can vary according to the methods used for its extraction and/or purification (EP 0138572 reg. on 25.7.90; EPA 0535200 published on 7.4.93; PCT Application No. WO 95/04132 published on 9.2.95; PCT Patent Application No. WO 95/24497 published on 14.9.95).
Besides the polymer's chemical-physical properties, the release methods and systems for biologically active molecules are also particularly important, such as microspheres which seem to be among the most versatile release systems. EPA 0517565 discloses a process for the preparation of microspheres, whose dimensions range between 1-100 μm, wherein the polysaccharide ester dissolved in an aprotic solvent such as DMSO, is added to a mixture of a high-viscosity mineral oil containing a non ionic surface active agent and ethyl acetate, which is a solvent for DMSO and the mineral oil, but not for the polysaccharide ester, which therefore precipitates in the form of microspheres having therefore the above mentioned dimensions.
Today, various techniques are known which involve the use of supercritical fluids for the production of finely subdivided particles with a narrow granulometric distribution curve. The supercritical antisolvent process is generally performed at moderate temperatures and enables the solvent to be completely removed from the precipitation environment. The applications concern substances that are heat-sensitive or difficult to handle, such as explosives (Gallagher, P. M. et al.. 1989, Supercritical Fluid Science and Technology —Am. Chem. Soc. 334-354). Other applications concern the production of polymers in the form of fibers (Dixon, D. J. et al, 1993, J. Appl. Polym. Sci. 50, 1929-1942) and in the form of microparticles, including microspheres (Dixon, D. J.,et al., 1993, AIChE J., 39, 1, pp 127-139). In the pharmaceutical field, the main interest is in the treatment of proteins (Tom, J. W., et al, 1994, Supercritical Fluid Engineering Science , pp 238-257, ACS Symp. Chap. 19, Ed. H. Kiran and J. F. Brennecke; Yeo, S. D., et al, 1993, Biotech. and Bioeng., 41, pp 341-346) and biodegradable polymers, such as poly(L-lactic acid) (Randolph, T. W., et al, 1993, Biotechnol, Prog., 9, 429-435; Yeo, S. D., et al, 1993, Macromolecules, 26, 6207-6210). Various methods have been devised for precipitation with a supercritical antisolvent. The semi-discontinuous method (Gallagher et al., 1989), involves injection of the antisolvent in the liquid solution which has already been prepared in the desired working conditions. The operation must be performed in a stepwise fashion to ensure that the liquid is removed, the final quantities of product are very limited and the spheres measure far more than 1 μ in size. Precipitation with a compressed antisolvent (PCA) involves injection of the solution in the high-density supercritical fluid (SCF) (Dixon et al., 1991; Dixon and Johnston, 1993). The injection times are much reduced to guarantee complete dissolution of the liquid, so the quantity of precipitate is very low, giving microfibers with an ordered structure.
The continuous process (Yeo et al., 1993a) enables the solution and the antisolvent to be injected simultaneously in the precipitation environment; the liquid expands and evaporates in the continuous phase, constituted by the SCF. The solution is injected through a micrometric nozzle with a diameter ranging between 10 and 30μ. Solutions must be diluted to avoid blocking the nozzle and to prevent reticulate structures being formed. Consequently, the quantity of solid solute injected is very low. Moreover, a high ratio between the volume of antisolvent and solution must be used to continuously remove the liquid solvent from the precipitation vessel.
When the solution is placed in the precipitator and the container is loaded by means of SCF up to the desired pressure, the process assumes a completely discontinuous character (Yeo et al., 1993 a,b). By this technique, microspheres with a diameter of over 1 μ have been obtained. All the methods described here are accompanied by a final washing step to prevent the precipitate being resolubilized by the solvent. However, none of the cited techniques has been specifically applied to the production of high-molecular-weight biocompatible polysaccharide polymers and in particular the HYAFFs, namely the ester of hyaluronic acid, which are obtained by the procedure described in U.S. Pat. No. 4,851,521.
SUMMARY OF THE INVENTION
The Applicant has unexpectedly found that with the discontinuous SAS technique it is possible to obtain in quantitative yields microspheres with a diameter of less than 1 μ comprising an ester of a biocompatible acidic polysaccharide polymer, selected from the group consisting of: hyaluronic acid esters, crosslinked esters of hyaluronic acid, esters of chitin, esters of pectin, esters of gellan, esters of alginic acid.
Object of the present invention are therefore microspheres having a mean dimension ≧0.1 μ and <1 μ comprising a biocompatible polysaccharide a polymer.
A further object of the present invention are pharmaceutical compositions administrable by oral, nasal, pulmonary, vaginal or rectal route, containing said microspheres as vehicling agents or carriers in combination with at least one active ingredient and optionally with further conventional excipients.
A further object of the present invention relates to said microspheres further comprising at least one of the following active principles: a pharmaceutically active polypeptide, a Granulocyte Macrofage Colony Stimulating Factor (GMCSF), a trophic factor, an immunoglobulin, a natural or a synthetic derivative of a ganglioside, an antiviral, an antiasthmatic an antiinflammatory agent, an antibiotic and an antimycotic agent.
A further object of the present invention relates to pharmaceutical compositions administrable by oral, nasal, pulmonary, vaginal or rectal route containing the microspheres inglobating the above mentioned active principles, optionally in combination with other conventional excipients.
A further object of the present invention relates to the use of said microspheres as carriers in the preparation of diagnostics and in agroalimentary industry. Moreover the microspheres having a diameter ranging from 0.1 to 1 μ containing a biocompatible acidic polysaccharide ester selected from the group consisting of:hyaluronic acid esters, esters of chitin, esters of pectin, esters of gellan, esters of alginic acid can be advantageously used as vehicling agent or carriers of a gene, for the preparation of pharmaceutical compositions for the treatment of diseases associated with genic defects.
A further object of the present invention resides in the discontinuous a process for the preparation of microspheres having a dimension comprised between 0.1 and 1 μ and comprising the precipitation of said polymer induced by means of a supercritical antisolvent (SAS). The process object of the present invention comprises the following steps:
a) dissolving the polysaccharide biocompatible polymer in an aprotic solvent at concentrations ranging from 0.1 to 5% by weight,
b) charging the solution of step (a) in a pressure proof container having at the top and at the base steel filters with an average cutoff lower than 0.1 μ;
c) loading from underneath the antisolvent until reaching the pressure at which said fluid becomes supercritical at a temperature ranging from 25 to 60° C.,
d) removing the aprotic solvent, by flowing said supercritical fluid,
e) depressurizing the pressure proof container and collecting the precipitated product.
Contrarily to what one could foresee from the above mentioned prior art (teaching that, with the SAS discontinuous technique, process times are longer than with the continuous one, nucleation occurs in the bulk liquid phase where the supercritical antisolvent is dissolved and therefore the formation of large particles with broad granulometric distribution is expected) surprisingly the expanding conditions adopted with the process according to the present invention enable the onset of the nucleation process in a well-expanded media so that the formation of a high number of nucleation centers is achieved. This factor, combined with the amorphous nature of the solid solute, leads to the formation of microspheres whose dimension is comprised in the above mentioned range and moreover with a narrow granulometric distribution curve.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 represents a SEM photograph (Scanning Electron Microscope) of -HYAFF-11 microspheres obtained by following the operating conditions reported in Example 1, starting from a HYAFF concentration in DMSO equal to 1% w/w (bar=1 micron);
FIG. 2 is a photograph of the sample relative to FIG. 1 with a higher magnification (bar=1 micron);
FIG. 3 represents a SEM photograph of HYAFF-11 microspheres obtained according to the working conditions of Example 2, starting from a HYAFF concentration in DMSO equal to 1% w/w (bar=1 micron);
FIG. 4 represents a SEM photograph of HYAFF-7 microspheres prepared by following the operating conditions described in Example 3, starting from a HYAFF concentration in DMSO equal to 1% w/w (bar−1 micron);
FIG. 5 represents a SEM photograph of ACP p10 microspheres obtained by following the operating conditions described in Example 4, starting from an ACP concentration in DMSO equal to 1% W/W (bar=1 micron);
FIG. 6 represents a SEM photograph of ALAFF microspheres, prepared by following the operating conditions described in Example 5 starting from an ALAFF concentration in DMSO equal to 1% w/w (bar=1 micron).
DETAILED DESCRIPTION OF THE INVENTION
The biocompatible polysacharide polymer which is comprised in the microspheres according to the present invention is preferably an ester of a polysaccharide said such a hyaluronic acid ester, selected from those described U.S. Pat. No. 4,851,521, which we incorporate by reference, a crosslinked ester of hyaluronic acid selected from those disclosed in EP 0341745 B1 which we incorporate by reference, an ester of chitin selected from those described in PCT WO93/06136, which we incorporate by reference, an ester of pectin selected from those mentioned in PCT WO93/14129, which we incorporate by reference, an ester of gellan selected from those disclosed in U.S. Pat. No. 5,332,809, which we incorporate by reference, an ester of alginic acid selected from those reported in U.S. Pat. Nos. 5,264,422 and 5,336,668, which we incorporate by reference. Particularly preferred esters are the total or partial benzyl ester of hyaluronic acid. Among the partial ester a particularly preferred ester is the benzyl ester with 75% of the carboxy function of hyaluronic acid esterified with benzyl alcohol.
The pharmaceutical compositions according to the present invention containing said microspheres as vehicling agents or carriers, in combination with at least one active agent can optionally be formulated in a controlled release form, in order to have the desired rate of absorption, with suitable excipients normally used for preparing this type of formulations.
Preferred pharmaceutically active polypeptides which can be comprised in the microspheres according to the present invention are calcitonin, insulin, preferred trophic factors, which can be incorporated in the microspheres according to the present invention are the Nerve Growth Factor (h-NGF), the Ciliary Neuronotrophic Growth Factor (h-CNTF). The pharmaceutical compositions containing the above microspheres incorporating the above listed active principles, can optionally be formulated in controlled release form, in order to have the desired rate of absorption, with suitable excipients normally used for preparing this type of formulations.
As pointed out above the microspheres having a mean diameter ≧0.1 μ and <1 μ can be advantageously used as vehicling agents in the preparation of diagnostics. In particular, according to the type of technique to be used for diagnostic analysis, such as NMR, ultrasound, X rays, the microspheres can be loaded with paramagnetic agents such as magnetite, or they may be concave in structure, or, alternatively, they may be loaded with nonionic contrast agents, or, lastly, with radioactive isotopes such as TC 99m .
As a matter of fact vehicling of the contrast agents by means of microspheres limits interaction with the blood, thus reducing the onset of the side effects typically caused by contrast agents.
As previously pointed out, another important sector in which the microspheres having a diameter comprised between 0.1 and 1 μ according to the present invention can be advantageously used is the preparation of pharmaceutical compositions for the treatment of diseases associated with genic defects.
Much effort is currently being put into scientific research in this field to find remedies for genetic-type malformations or metabolic diseases of a genetic origin. Most of the work being done is aimed at identifying and preparing vehicling systems for healthy genetic material to be administered to patients suffering from such malformations and diseases. One of the possibilities is represented by the encapsulation of healthy genes in microspheres which are able to penetrate more deeply into the tissues and sustain contact with the cell surfaces to be treated for longer periods of time. It follows that the adherence of the microspheres to the cell surfaces enables the release of genetic material transported to the close vicinity of the target cells. In particular, the microspheres having a mean diameter ranging from 0.1 to 1 μ containing the biocompatible polysaccharide polymer according to the present invention represent an ideal transport system for biological material, and in this particular case for healthy genes, thanks to their very small dimensions and specific mucoadhesiveness. Among the possible applications for said microspheres in the treatment of human diseases associated with genic defects a preferred one is in their use as vehicling agents of single genes which encode specific enzymes, for the treatment of diseases caused by a deficit of the same enzymes. There are in fact numerous diseases which derive from an enzyme deficit or hyperactivity, which is caused by defects occurred in the specific gene encoding this enzyme.
For example diseases of this type are:
phenylketonuria, due to a deficit of phenylalanine hydroxylase,
alkaptonuria, due to a deficit of homogentisic acid oxidase,
albinism due to a deficit of tyrosinase and many other diseases involving amino acid Metabolism;
diseases involving glycogen accumulation, some of which are fatal at birth, due to deficit of enzymes such as glucose-6-phosphatase, brancher or de-brancher enzymes, and α-lysosomal glucosidase enzymes;
carbohydrate metabolism disorders
Wilson's disease, involving a defect in ceruloplasma, the protein which transports copper
porphyria caused by a deficit in porphobilinogen deaminase, uroporphyrinogen oxydase, protoporphyrinogen oxydase coproporphyrinogen oxydase,
gout due to hypoxanthine-guanine-phosphoribosyl transferase deficiency, or hyperactivity of 5-phosphoribosyl-1-pyrophosphate
transferase,
diseases involving lysosomal accumulation such as gangliosidosis, due to β-galactosidase deficiency, leukodystrophy, Niemann-Pick's disease due to sphingomyelinase deficiency, Gaucher's disease due to glucosyl-ceramidase deficiency, Fabry's disease, due to α-galactosidase deficiency, mucopolysaccharidosis etc.,
connective tissue disorders (brittle bone syndrome, Ehlers-Danlos syndrome, Marfan syndrome),
Besides their use in enzymatic deficits, the microspheres can be used to vehicle single genes in any pathologies wherein such genes are altered, such as malformative diseases of genetic origin (Down's syndrome, arachnodactyly etc.), hereditary diseases such as:
hemoglobinopathies (sickle-cell anaemia, thalassaemia etc),
cystic fibrosis,
primitive hyperlipoproteinemia and other lipid metabolism disorders, wherein single or multifactorial gene disorders with hereditary transmission and complex modalities of different genes, interact with environmental factors, thus determining hyperlipoproteinemia having a different degree of seriousness in different members of the same family,
cancer wherein it has been ascertained that genetic alterations exist at the level of the differentiation and of the failed control of cellular growth.
Finally as pointed out above, the microspheres having a mean diameter ≧0.1 μ and <1 μ can be advantageously used in the agro-alimentary sector, for example as a vehicle for plant treatments or for the preservation of additives.
The preferred supercritical fluid used as antisolvent in the process according to the present invention is selected from carbon dioxide (CO 2 ) and hydrofluorocarbons, such as trifluoromethane.
In this specific case when CO 2 in step (c) it is charged with a loading rate or pressure gradient ranging from 3 to 20 bar/min, preferably 10 bar/min, until a pressure is reached in the pressure proof container ranging from 80 to 120 bar/min, more preferably 100 bar/min.
Precipitation of the polymer in this step is induced by the supercritical antisolvent which, by solubilizing and expanding the solution, causes a decrease in the solvent power of the liquid and simultaneous evaporation. The dissolved product, not soluble in the SCF, separates as a solid.
The particles in step (d) are washed with the antisolvent to remove the liquid completely before the precipitator is depressurized.
The depressurization in step (e) of the process according to the present invention is preferably carried out using a pressure gradient of 5 bar/min.
The preferred solvent used in step (a) to dissolve the biocompatible polysaccharide polymer is selected from dimethylsulfoxide and N-methylpyrrolidone.
The microspheres according to the present invention further comprising at least one of the above mentioned active principles can be prepared in two alternative ways.
The first one encompasses the addition of the active principle in step (a) of the process according to the present invention, after the dissolution of the biocompatible polysaccharide polymer in the aprotic solvent.
The coprecipitation of the active principle in step (c) with the biocompatible polysaccharide polymer does not alter the form or morphology of the precipitate.
According to the latter way, the microspheres coming from step (e), are suspended in a buffered solution preferably a phosphate buffer solution containing the desired active principle at a suitable concentration in order to obtain the desired active ingredient titer/mg of microsphere, and the suspension is subjected to liophylization at the liquid nitrogen temperature.
We report hereafter, for purely illustrative purposes, some examples of how to obtain microspheres made with polymer alone or with polymer containing pharmacologically active substances. Any variations which would be obvious to an expert in the field are to be considered as coming within the scope of the present invention.
EXAMPLE 1
Preparation of Microspheres Wherein the Starting Polymer is HYAFF-11 (Benzyl Ester of Hyaluronic Acid)
A hyaluronic acid ester, wherein all the carboxy groups of hyaluronic acid are esterified with benzyl alcohol, is dissolved in an aprotic solvent, such as dimethylsulfoxide (DMSO), at a concentration varying between 0.1 and 5% in weight, generally 1% w/w. Once the polymer has solubilized, the solution is poured into a pressure-proof container (precipitator), thermostatically controlled with a heated ethylene glycol jacket. Porous steel filters with an average cut-off of less than 0.1 μ are screwed onto the base and top of the precipitator.
The liquid is unable to seep through by gravity alone.
Once the container is closed, it is loaded from underneath with hyperpure carbon dioxide (CO 2 ) until the working pressure is reached (80-120 bar, preferably 100 bar). The CO 2 is dispersed in the solution through the filter. This antisolvent, which is first gaseous and then supercritical, can be mixed perfectly with the liquid solvent (DMSO) but it is a nonsolvent for the polymer.
The loading rate, or the pressure gradient over time, is set in a range of 3-20 bar/min, preferably 10 bar/min. The temperature in the precipitator is kept constant in a range of between 25° C. and 60° C., preferably 40° C.
When the working pressure has been reached, the flow of CO 2 is switched off for 10 minutes to obtain the desired pressure and temperature conditions inside the precipitator. The washing operation is begun by supplying antisolvent to the precipitator and regulating the outlet flow from the top of the precipitator by means of a millimetric valve.
The outlet fluid, constituted by antisolvent and DMSO, is directed towards the DMSO collector, which is kept at room pressure; the DMSO separates after expansion and consequent cooling, while the gaseous CO 2 comes out of the top of the container and is released into the atmosphere. The solid particles, on the other hand, are trapped by the porous filters at the top and base of the precipitator.
The operation is continued to allow the DMSO to be completely removed from the precipitator. The time it takes for the organic solvent to be removed by the supercritical antisolvent depends on the temperature in the precipitation chamber, when fixed amount of liquid solution an antisolvent flow rate are set up.
At the end of washing, the supply of CO 2 is cut off and the container is depressurized at a race of 5 bar/min. The container is opened, the microspheres are collected and placed in suitable containers where they are stored at 4° C. The yield of microspheres is almost total. There is no appreciable incorporation of solvent in the precipitate.
The DMSO is collected in the expansion container.
The mean particle size in these working conditions is 0.6 μ.
EXAMPLE 2
Preparation of Microspheres Wherein the Starting Polymer is HYAFF-11 p75 (Partial Benzyl Ester of Hyaluronic Acid)
A hyaluronic acid ester, wherein 75% of the carboxy groups of hyaluronic acid are esterified with benzyl alcohol, while the remaining part is salified with sodium, is dissolved in an aprotic solvent such as dimethylsulfoxide (DMSO), at a concentration varying between 0.1 and 5% in weigh, generally 1% w/w. Once the polymer has reached solubilizaticn, the solution is poured into a pressure-proof container (precipitator) thermostatically controlled by a heated ethylene glycol jacket. Porous steel filters with a cut-off of 0.1 μ are screwed onto the top and base of the precipitator. The liquid is unable to seep through by gravity alone.
Once the vessel is close, it is loaded from underneath with hyperpure carbon dioxide (CO 2 ) until the working pressure is reached (80-120 bar, preferably 100 bar), he CO 2 is distributed in the solution through the porous filter. This antisolvent, which is first gaseous and then supercritical, can be mixed perfectly with the liquid solvent (DMSO) but it is a nonsolvent for the polymer.
The loading rate, or the pressure gradient over time, is set in a range of 3-20 bar/min, preferably 10 bar/min. The temperature in the precipitator is kept constant in a range of between 25° C. and 60° C., preferably 40° C.
When the working pressure has been reached, the flow of CO 2 is switched off for 10 minutes to obtain the desired pressure and temperature conditions inside the precipitator. The washing operation is begun by supplying antisolvent to the precipitator and regulating the outlet flow from the top of the precipitator by means of a 10 millimetric valve.
The outlet fluid, constituted by antisolvent and DMSO, is directed towards the DMSO collector, which is kept at room pressure; the DMSO separates after expansion and consequent cooling, while the gaseous CO 2 comes out of the top of the vessel and is dispersed in the atmosphere. The solid particles, on the other hand, are trapped by the porous filters at the top and bottom of the precipitator.
The operation is continued to allow the DMSO to be completely removed from the precipitator. The time it takes for the organic solvent to be removed by the supercritical antisolvent depends on the temperature in the precipitation chamber, when fixed amount of liquid solution and antisolvent flow rate are set up.
At the end of washing, the supply of CO 2 is cut off and the vessel is depressurized at a rate of 5 bar/min. The vessel is opened, the microspheres are collected and placed in suitable containers where they are stored at 4° C. The yield of microspheres is almost total. There is no appreciable incorporation of solvent in the precipitate. The DMSO is collected in the expansion container.
The mean particle size in these working conditions is 0.8 μ (FIG. 3)
EXAMPLE 3
Preparation of Microspheres Wherein the Starting Polymer is HYAFF-7 (Ethyl Ester of Hyaluronic Acid)
A hyaluronic acid ester, wherein all the carboxy groups of hyaluronic acid are esterified with ethyl alcohol, is dissolved in an aprotic solvent such as dimethylsulfoxide (DMSO), at a concentration varying between 0.1 and 5% in weight, generally 1% w/w. Once the polymer has reached solubilization, the solution is poured into a pressure-proof vessel (precipitator), thermostatically controlled by a heated ethylene glycol jacket. Porous steel filters with a cut-off of 0.1 are screwed onto the top and bottom of the precipitator. The liquid is unable to seep through by gravity alone.
Once the vessel is closed, it is loaded from underneath with hyperpure carbon dioxide (CO 2 ) until the working pressure is reached (80-120 bar, preferably 100 bar). The CO 2 ) is distributed in the solution through the porous base. This antisolvent, which is first gaseous and then supercritical, can be mixed perfectly with the liquid solvent (DMSO) but it is a nonsolvent for the polymer.
The loading rate, or the pressure gradient over time, is set in a range of 3-20 bar/min, preferably 10 bar/min. The temperature in the precipitator is kept constant in a range of between 25° C. and 60° C., preferably 40° C.
When the working pressure has been reached, the flow of CO 2 is switched off for 10 minutes to obtain the desired pressure and temperature conditions inside the precipitator. The washing operation is begun by supplying antisolvent to the precipitator and regulating the outlet flow from the top of the precipitator by means of a millimetric valve.
The outlet fluid, constituted by antisolvent and DMSO, is directed towards the DMSO collector, which is kept at room pressure; the DMSO separates after expansion and consequent cooling, while the gaseous CO 2 comes out of the top of the vessel and is released into the atmosphere. The solid particles, on the other hand, are trapped by the porous filters at the top and base of the precipitator. The operation is continued to allow the DMSO to be completely removed from the precipitator. The time it takes for the organic solvent to be removed by the supercritical antisolvent depends on the temperature in the precipitation chamber, when fixed amount of liquid solution and antisolvent flow rate are set up.
At the end of washing, the supply of CO 2 is cut off and the vessel is depressurized at a rate of 5 bar/min. The vessel is opened, the microspheres are collected acid placed in suitable containers where they are stored at 4° C. The field of microspheres is almost total. There is no appreciable incorporation of solvent in the precipitate. The DMSO is collected in the expansion container.
The mean particle size in these working conditions is 1.0 μ (FIG. 4 ).
EXAMPLE 4
Preparation of Microspheres Wherein the Starting Polymer is a Crosslinked Polysaccharide of Hyaluronic Acid (ACP)
A hyaluronic acid derivative, wherein 10% of the carboxy groups of hyaluronic acid are bound with inter- or intramolecular hydroxy groups and the remaining part is salified with sodium, is dissolved in an aprotic solvent such as dimethylsulfoxide (DMSO), at a concentration varying between 0.1 and 5% in weight, generally 1% w/w. The procedure described in Example 1 is then performed. The mean particle size is 0.6 μ (FIG. 5 ).
EXAMPLE 5
Preparation of Microspheres Wherein the Starting Polymer is an Ester of Alginic Acid (ALAFF)
A derivative of alginic acid, wherein all the carboxy groups of alginic acid are esterified with benzyl alcohol, is dissolved in an aprotic solvent, such as dimethylsulfoxide (DMSO), at a concentration varying between 0.1 and 5% in weight, generally 1% w/w. The procedure described in Example 1 is then performed. The mean particle size is 0.8 μ (FIG. 6 ).
EXAMPLE 6
Preparation of Microspheres Wherein the Starting Polymer is an ester of pectinic acid
A derivative of pectinic acid, wherein all the carboxy groups are esterified with benzyl alcohol, is dissolved in an aprotic solvent, such as dimethylsulfoxide (DMSO), at a concentration varying between 0.1 and 5% in weight, generally 1% w/w. The procedure described in Example 1 is then performed.
The mean particle size is 0.7 μ.
EXAMPLE 7
Preparation of Microspheres wherein the Starting Polymer is HYAFF-11 (Benzyl Ester of Hyaluronic Acid) and which are Loaded with Calcitonin
A hyaluronic acid ester, wherein all the carboxy groups of hyaluronic acid are esterified with benzyl alcohol, is dissolved in an aprotic solvent such as dimethylsulfoxide (DMSO), at a concentration varying between 0.1% and 5% in weight, generally 1% w/w. Once the polymer has reached solubilization, the calcitonin is added to the polymeric solution at the set concentration, eg 1.5 I.U. per mg of polymer.
The solution thus obtained is poured into a pressure-proof vessel (precipitator), thermostatically controlled by a heated ethylene glycol jacket. Porous steel filters with a cut-off of 0.1 μ are screwed onto the top and base of the precipitator. The liquid is unable to seep through by gravity alone. Once the vessel is closed, it is loaded from underneath with hyperpure carbon dioxide (CO 2 ) until the working pressure is reached (80-120 bar, preferably 100 bar). The CO 2 is distributed in the solution through the porous base. This antisolvent, which is first gaseous and then supercritical, can be mixed perfectly with the liquid solvent (DMSO) but it is a nonsolvent for the polymer and the polypeptide calcitonin.
The loading rate, or the pressure gradient over time, is set in a range of 3-20 bar/min, preferably 10 bar/min. The temperature in the precipitator is kept constant in a range of between 25° C. and 60° C., preferably 40° C.
When the working pressure has been reached, the flow of CO 2 is switched off for 10 minutes to obtain the desired pressure and temperature conditions inside the precipitator. The washing operation is begun by supplying antisolvent to the precipitator and regulating the outlet flow from the top of the precipitator by means of a millimetric Waive.
The outlet fluid, constituted by antisolvent and DMSO, is directed towards the DMSO collector, which is kept at room pressure; the DMSO separates after expansion and consequent cooling, while the gaseous CO 2 comes out of the top of the vessel and is released into the atmosphere. The solid particles, on the other hand, are trapped by the porous filters at the top and base of the precipitator. The operation is continued to allow the DMSO to be completely removed from the precipitator. The time it takes for the organic solvent to be removed by the supercritical antisolvent depends on the temperature in the precipitation chamber, when fixed amount of liquid solution and antisolvent flow rate are set up.
At the end of washing, the supply of CO 2 is cut off and the vessel is depressurized at a rate of 5 bar/min. The vessel is opened, the microspheres are collected and placed in suitable containers where they are stored at 4° C. The yield of microspheres is almost total. There is no appreciable incorporation of solvent in the precipitate. The DMSO is collected in the expansion container.
The mean particle size in these working conditions is 0.5 μ. The quantity of incorporated calcitonin is 1.3 I.U. per mg of microspheres.
EXAMPLE 8
Preparation of Microspheres Wherein the Starting Polymer is HYAFF-11 p75 (Benzyl Ester of Hyaluronic Acid) and Which are Loaded with calcitonin
A hyaluronic acid ester, wherein 75% of the carboxy groups of hyaluronic acid are esterified with benzyl alcohol, while the remaining part is salified with sodium, is dissolved in an aprotic solvent such as dimethylsulfoxide (DMSO), at a concentration varying between 0.1 and 5% in weight, generally 1m% w/w. Once the polymer has reached solubilization, calcitonin is added to the polymeric solution at a set concentration, eg 1.0 I.U. per mg of polymer.
The solution thus obtained is poured into a pressure-proof vessel (precipitator), thermostatically controlled by a heated ethylene glycol jacket. Porous steel filters with a cut-off of 0.1 μ are screwed onto the top and base of the precipitator. The liquid is unable to seep through by gravity alone.
Once the vessel is closed, it is loaded from underneath with hyperpure carbon dioxide (CO 2 ) until the working pressure is reached (80-120 bar, preferably 100 bar). The CO 2 is distributed in the solution through the porous filter. This antisolvent, which is first gaseous and then supercritical, can be mixed perfectly with the liquid solvent (DMSO) but it is a nonsolvent for the polymer and the polypeptide calcitonin.
The loading rate, or the pressure gradient over time, is set in a range of 3-20 bar/min, preferably 10 bar/min. The temperature in the precipitator is kept constant in a range of between 25° C. and 60° C. preferably 40° C.
When the working pressure has been reached, the flow of CO 2 is switched off for 10 minutes to obtain the desired pressure and temperature conditions inside the precipitator. The washing operation is begun by supplying antisolvent to the precipitator and regulating the outlet flow from the top of the precipitator by means of a millimetric valve.
The outlet fluid, constituted by antisolvent and DMSO, is directed towards the DMSO collector, which is kept at room pressure; the DMSO separates after expansion and consequent cooling, while the gaseous CO 2 comes out of the top of the vessel and is released into the atmosphere. The solid particles, on the other hand, are trapped by the porous filters at the top and base of the precipitator.
The operation is continued to allow the DMSO to be completely removed from the precipitator. The time it takes for the organic solvent to be removed by the supercritical antisolvent depends on the temperature in the precipitation chamber, when fixed amount of liquid solution and antisolvent flow rate are set up.
At the end of washing, the supply of CO 2 is cut off and the vessel is depressurized at a rate of 5 bar/min. The vessel is opened, the microspheres are collected and placed in suitable containers where they are stored at 4° C. The yield of microspheres is almost total. There is no appreciable incorporation of solvent in the precipitate. The DMSO is collected in the expansion container.
The mean particle size in these working conditions is 0.8 μ. The quantity of incorporated calcitonin is 0.9 I.U. per mg of microspheres.
EXAMPLE 9
Preparation of Microspheres wherein the Starting Polymer is HYAFF-7 (Ethyl Ester) of Hyaluronic Acid, and which are Loaded with Calcitonin
A hyaluronic acid ester, wherein all the carboxy groups of hyaluronic acid are esterified with ethyl alcohol, is dissolved in an aprotic solvent such as dimethylsulfoxide (DMSO), at a concentration varying between 0.1 and 5% in weight, generally 1% w/w. Once the polymer has reached solubilization, calcitonin is added to the polymeric solution at a set concentration, eg 15 I.U. per mg of polymer.
The solution thus obtained is poured into a pressure-proof vessel (precipitator), thermostatically controlled by a heated ethylene glycol jacket. Porous steel filters with a cut-off of 0.1 μ are screwed onto the top and base of the precipitator. The liquid is unable to seep through by gravity alone.
Once the vessel is closed, it is loaded from underneath with hyperpure carbon dioxide (CO 2 ) until the working pressure is reached (80-120 bar, preferably 100 bar). The CO 2 is distributed in the solution through the porous base. This antisolvent, which is first gaseous and then supercritical, can be mixed perfectly with the liquid solvent (DMSO) but it is a nonsolvent for the polymer and the polypeptide calcitonin.
The loading rate, or the pressure gradient over time, is set in a range of 3-20 bar/min, preferably 10 bar/min. The temperature in the precipitator is kept constant in a range of between 25° C. and 60° C., preferably 40° C.
When the working pressure has been reached, the flow of CO 2 is switched off for 10 minutes to obtain the desired pressure and temperature conditions inside the precipitator. The washing operation is begun by supplying antisolvent to the precipitator and regulating the outlet flow from the top of the precipitator by means of a millimetric valve.
The outlet fluid, constituted by antisolvent and DMSO, is directed towards the DMSO collector, which is kept at room pressure; the DMSO separates after expansion and consequent cooling, while the gaseous CO 2 comes out of the top of the vessel and is released into the atmosphere. The solid particles, on the other hand, are trapped by the porous filters at the top and bottom of the precipitator.
The operation is continued to allow the DMSO to be completely removed from the precipitator. The time it takes for the organic solvent to be removed by the supercritical antisolvent depends on the temperature in the precipitation chamber, when fixed amount of liquid solution and antisolvent flow rate are set up.
At the end of washing, the supply of CO 2 is cut off and the vessel is depressurized at a rate of 5 bar/min. The vessel is opened, the microspheres are collected and placed in suitable containers where they are stored at 4° C. The yield of microspheres is almost total. There is no appreciable incorporation of solvent in the precipitate. The DMSO is collected in the expansion container.
The mean particle size in these working conditions is 1.0 μ. The quantity of incorporated calcitonin is 13 I.U. per mg of microspheres.
EXAMPLE 10
Preparation of Microspheres Wherein the Starting Polymer is HYAFF-11 (Benzyl Ester of Hyaluronic Acid), and which Contain GMCSF (Granulocyte Macrophage Colony Stimulating Factor).
A hyaluronic acid ester, wherein all the carboxy groups of hyaluronic acid are esterified with benzyl alcohol, is dissolved in an aprotic solvent such as dimethylsulfoxide (DMSO), at a concentration which varies between 0.1 and 5% in weight, generally 1% w/w. Once the polymer has reached solubilization. GMCSF is added to the polymer solution at a set concentration. eg 1% of the polymer mass. The solution thus obtained is poured into a pressure-proof vessel (precipitator), thermostatically controlled by a heated ethylene glycol jacket. Porous steel filters with a cut-off of 0.1 μare screwed onto the top and base of the precipitator. The liquid is unable to seep through by gravity alone.
Once the vessel is closed, it is loaded from underneath with hyperpure carbon dioxide (CO 2 ) until the working pressure is reached (80-120 bar, preferably 100 bar). The CO 2 is distributed in the solution through the porous base. This antisolvent, which is first gaseous and then supercritical, can be mixed perfectly with the liquid solvent (DMSO) but it is a nonsolvent for the polymer and the polypeptide GMCSF.
The loading rate, or the pressure gradient over time, is set in a range of 3-20 bar/min, preferably 10 bar/min. The temperature in the precipitator is kept constant in a range of between 25° C. and 60° C., preferably 40° C.
When the working pressure has been reached, the flow of CO 2 is switched off for 10 minutes to obtain the desired pressure and temperature conditions inside the precipitator. The washing operation is begun by supplying antisolvent to the precipitator and regulating the outlet flow from the top of the precipitator by means of a millimetric valve.
The outlet fluid, constituted by antisolvent and DMSO, is directed towards the DMSO collector, which is kept at room pressure; the DMSO separates after expansion and consequent cooling, while the gaseous CO 2 comes out of the top of the vessel and is released into the atmosphere. The solid particles, on the other hand, are trapped by the porous filters at the top and base of the precipitator.
The operation is continued to allow the DMSO to be completely removed from the precipitator. The time it takes for the organic solvent to be removed by the supercritical antisolvent depends on the temperature in the precipitation chamber, when fixed amount of liquid and antisolvent flow rate are set up.
At the end of washing, the supply of CO 2 is cut off and the vessel is depressurized at a rate of 5 bar/min. The vessel is opened, the microspheres are collected and placed in suitable containers where they are stored at 4° C. The yield of microspheres is almost total. There is no appreciable incorporation of solvent in the precipitate. The DMSO is collected in the expansion container.
The mean particle size in these working conditions is 0.5 μ. The quantity of incorporated GMCSF is 9 μg. per mg of microspheres.
EXAMPLE 11
Preparation of Microspheres Wherein the Starting Polymer is HYAFF-11 p75 (Benzyl Ester of Hyaluronic Acid), and which Contain GMCSF Granulocyte Macrophage Colony Stimulating Factor)
A hyaluronic acid ester, wherein 75% of the carboxy groups of hyaluronic acid are esterified with benzyl alcohol while the remaining part is salified with sodium, is dissolved in an aprotic solvent such as dimethylsulfoxide (DMSO), at a concentration varying between 0.1 and 5% in weight, generally 1% w/w. Once the polymer has reached solubilization, GMCSF is added to the polymeric solution at a set concentration, eg 2% of the polymer mass.
The solution thus obtained is poured into a pressure-proof vessel (precipitator), thermostatically controlled by a heated ethylene glycol jacket. Porous steel filters with a cut-off of 0.1 μ are screwed onto the top and base of the precipitator. The liquid is unable to seep through by gravity alone.
Once the vessel is closed, it is loaded from underneath with hyperpure carbon dioxide (CO 2 ) until the working pressure is reached (80-120 bar, preferably 100 bar). The CO 2 is distributed in the solution through the porous base. This antisolvent, which is first gaseous and then supercritical, can be mixed perfectly with the liquid solvent (DMSO) but it is a nonsolvent for the polymer and the polypeptide GMCSF.
The loading rate, or the pressure gradient over time, is set in a range of 3-20 bar/min, preferably 10 bar/min. The temperature in the precipitator is kept constant in a range of between 25° C. and 60° C., preferably 40° C. When the working pressure has been reached, the flow of CO 2 is switched off for 10 minutes to obtain the desired pressure and temperature conditions inside the precipitator. The washing operation is begun by supplying antisolvent to the precipitator and regulating the outlet flow from the top of the precipitator by means of a millimetric valve.
The outlet fluid, constituted by antisolvent and DMSO, is directed towards the DMSO collector, which is kept at room pressure; the DMSO separates after expansion and consequent cooling, while the gaseous CO 2 comes out of the top of the vessel and is released into the atmosphere. The solid particles, on the other hand, are trapped by the porous filters at the top of and base of the precipitator.
The operation is continued to allow the DMSO to be completely removed from the precipitator. The time it takes for the organic solvent to be removed by the supercritical antisolvent depends on the temperature in the precipitation chamber, when fixed amount of liquid solution and antisolvent flow rate are set up.
At the end of washing, the supply of CO 2 is cut off and the vessel is depressurized at a rate of 5 bar/min. The vessel is opened, the microspheres are collected and placed in suitable containers where they are stored at 4° C. The yield of microspheres is almost total.
There is no appreciable incorporation of solvent in the precipitate. The DMSO is collected in the expansion container. The mean particle size in these working conditions is 0.8 μ. The quantity of incorporated GMCSF is 17 μg per mg of microspheres.
EXAMPLE 12
Preparation of Microspheres Wherein the Starting Polymer is HYAFF-7 (Ethyl Ester of Hyaluronic Acid), and which are Loaded with GMCSF (Granulocyte Macrophage Colony Stimulating Factor)
A hyaluronic acid ester, wherein all the carboxy groups of hyaluronic acid are esterified with ethyl alcohol, is dissolved in an aprotic solvent such as dimethylsulfoxide (DMSO), at a concentration varying between 0.1 and 5% in weight, generally 1% w/w. Once the polymer has reached solubilization, GMCSF is added to the polymeric solution at a set concentration, eg 0.1% of the polymer mass.
The solution thus obtained is poured into a pressure-proof vessel (precipitator), thermostatically controlled by a heated ethylene glycol jacket. Porous steel filters with a cut-off of 0.1μ are screwed onto the top and base of the precipitator. The liquid is unable to seep through by gravity alone.
Once the vessel is closed, it is loaded from underneath with hyperpure carbon dioxide (CO 2 ) until the working pressure is reached 80-120 bar, generally 100 bar). The CO 2 is distributed in the solution through the porous base. This antisolvent, which is first gaseous and then supercritical, can be mixed perfectly with the liquid solvent (DMSO) but it is a nonsolvent for the polymer and the polypeptide GMCSF.
The loading rate, or the pressure gradient over time, is set in a range of 3-20 bar/min, preferably 10 bar/min. The temperature in the precipitator is kept constant in a range of between 25° C. and 60° C., preferably 40° C.
When the working pressure has been reached, the flow of CO 2 is switched off for 10 minutes to obtain the desired pressure and temperature conditions inside the precipitator. The washing operation is begun by supplying antisolvent to the precipitator and regulating the outlet flow from the top of the precipitator by means of a millimetric valve.
The outlet fluid, constituted by antisolvent and DMSO, is directed towards the DMSO collector, which is kept at room pressure; the DMSO separates after expansion and consequent cooling, while the gaseous CO 2 comes out of the top of the vessel and is released into the atmosphere. The solid particles, on the other hand, are trapped by the porous filters at the top and bottom of the precipitator.
The operation is continued to allow the DMSO to be completely removed from the precipitator. The time it takes for the organic solvent to be removed by the supercritical antisolvent depends on the temperature in the precipitation chamber, when fixed amount of liquid solution and antisolvent flow rate are set up.
At the end of washing, he supply of CO 2 is cut off and the vessel is depressurized at a rate of 5 bar/min. The vessel is opened, the microspheres are collected and placed in suitable containers where they are stored at 4° C. The yield of microspheres is almost total. There is no appreciable incorporation of solvent in the precipitate. The DMSO is collected in the expansion container.
The mean particle size in these working conditions is 1.0 μ. The quantity of incorporated GMCSF is 0.9 μg per mg of microspheres.
EXAMPLE 13
Preparation of Microspheres Wherein the Starting Polymer is HYAFF-11 (Benzyl Ester of Hyaluronic Acid), and which are Loaded with Human Insulin
A hyaluronic acid ester, wherein all the carboxy groups of hyaluronic acid are esterified with benzyl alcohol, is dissolved in an aprotic solvent such as dimethylsulfoxide (DMSO), at a concentration varying between 0.1 and 5% in weight, generally 1% w/w. Once the polymer has reached solubilization, human insulin is added to the polymeric solution at a set concentration, eg 5 I.U. per mg of polymer.
The solution thus obtained is poured into a pressure-proof vessel (precipitator), thermostatically controlled by a heated ethylene glycol jacket. Porous steel filters with a cut-off of 0.1μ are screwed onto the top and base of the precipitator. The liquid is unable to seep through by gravity alone.
Once the vessel is closed, it is loaded from underneath with hyperpure carbon dioxide (CO 2 ) until the working pressure is reached (80-120 bar, preferably 100 bar). The CO 2 is distributed in the solution through the porous base. This antisolvent, which is first gaseous and then supercritical, can be mixed perfectly with the liquid solvent (DMSO) but it is a nonsolvent for the polymer and the polypeptide human insulin.
The loading rate, or the pressure gradient over time, is set in a range of 3-20 bar/min, preferably 10 bar/min. The temperature in the precipitator is kept constant in a range of between 25° C. and 60° C., preferably 40° C.
When the working pressure has been reached, the flow of CO 2 is switched off for 10 minutes to obtain the desired pressure and temperature conditions inside the precipitator. The washing operation is begun by supply by supplying antisolvent to the precipitator and regulating the outlet flow from the top of the precipitator by means of a millimetric valve.
The outlet fluid, constituted by antisolvent and DMSO, is directed towards the DMSO collector, which is kept at room pressure; the DMSO separates after expansion and consequent cooling, while the gaseous CO 2 comes out of the top of the vessel and is released into the atmosphere. The solid particles, on the other hand, are trapped by the porous filters at the top and bottom of the precipitator.
The operation is continued to allow the DMSO to be completely removed from the precipitator. The time it takes for the organic solvent to be removed by the supercritical antisolvent depends on the temperature in the precipitation chamber, when fixed amount of liquid solution and antisolvent flow rate are set up.
At the end of washing, the supply of CO 2 is cut off and the vessel is depressurized at a rate of 5 bar/min. The vessel is opened, the microspheres are collected and placed in suitable containers where they are stored at 4° C. The yield of microspheres is almost total. There is no appreciable incorporation of solvent in the precipitate. The DMSO is collected in the expansion container.
The mean particle size in these working conditions is 0.8 μ. The quantity of incorporated insulin is 5 I.U. per mg of microspheres.
EXAMPLE 14
Surface Loading of Microspheres of HYAFF-11 (Benzyl Ester of Hyaluronic Acid) with Calcitonin by Lyophilization
Microspheres prepared according to Example 1 are suspended in a solution of 0.01 M phosphate buffer, containing calcitonin in a concentration which gives a protein titer of 1 I.U. per mg of suspended microspheres. After 15 minutes' shaking with a semiautomatic device, the container is immersed in liquid nitrogen until the suspension is completely frozen.
Once frozen, the container is lyophilized for 24 hours, after which the lyophilized product is stored at 4°C. The mean particle size in these working conditions is 0.4 μ. The quantity of incorporated calcitonin is 1 I.U. per mg of microspheres.
EXAMPLE 15
Surface Loading of Microspheres of HYAFF-11 p75 (Benzyl Ester of Hyaluronic Acid) with Calcitonin by Lyophilization
Microspheres prepared according to Example 2 are suspended in a solution of 0.01 M phosphate buffer, containing calcitonin in a concentration which gives a protein titer of 1.5 I.U. per mg of suspended microspheres. After 15 minutes' stirring with a semiautomatic device, the container is immersed in liquid nitrogen until the suspension is completely frozen.
Once frozen, the container is lyophilized for 24 hours, after which the lyophilized product is stored at 4° C.
The mean particle size in these working conditions is 0.6 μ. The quantity of incorporated calcitonin is 1.5 I.U. per mg of microspheres.
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Microspheres, having a size lower than 1μ and comprising a biocompatible polysaccharidic polymer, are prepared with a process comprising the precipitation of polymer induced by means of a supercritical antisolvent (SAS). These microspheres are used as vehicling agents or carriers in the preparation of pharmaceutical compositions administrable by oral, nasal, pulmonary, vaginal or rectal route. These microspheres can also be advantageously used as vehicling agent or carriers in the preparation of pharmaceutical compositions for the treatment of human diseases associated with genic defects, for the preparation of diagnostics and in the agro-alimentary industry.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to techniques for the detection of human pathogens in foods. More particularly, the present invention relates to a novel method useful for the detection and differentiation of virulent and avirulent strains of the bacterium Yersinia enterocolitica "Y. enterocolitica" using a crystal violet "CV" dye binding technique.
2. Description of the Prior Art
Y. enterocolitica is a potential human pathogen which has caused considerable concern in the food industry because of its ability to grow at refrigeration temperatures. Since its discovery over 40 years ago, the microorganism has been isolated from various food products including milk, milk products, egg products, raw meats, poultry and vegetables.
Various strains of Y. enterocolitica have been isolated. However, the disease-causing potential of the microorganism is associated with the virulent plasmid-bearing "P + " strains of enterocolitica. Consequently, the evaluation of foods as well as clinical and environmental samples for the presence of Y. enterocolitica requires the additional determination of the potential virulence of the strains isolated.
Presently, the evaluation of isolates of Y. enterocolitica requires either the use of sophisticated techniques such as radioactive DNA colony hybridization or plasmid profiling, or the use of clinical assessment techniques such as calcium dependency, serum resistance and autoagglutination. However, these techniques have proven to be impractical for field application. Besides being cumbersome, time consuming and expensive, clinical procedures are often not adaptable to large numbers of cultures and their results are often inconsistent. The colony hybridization technique requires the frequent preparation of the 32 P-labeled DNA probe which is inconvenient and expensive. Further, the colony hybridization technique is potentially hazardous since the method requires the handling of millicurie levels of radioactive material.
Consequently, there exists a need for a method for the evaluation of foods, environmental and clinical samples for the pathogen Y. enterocolitica, which is easy, economical, reliable and safe.
SUMMARY OF THE INVENTION
We have now developed a CV dye binding method which is useful for the detection of virulent strains of Y. enterocolitica and for the differentiation between virulent and avirulent strains of the bacteria. In the assay of the invention, CV binds selectively to virulent P 30 strains of Y. enterocolitica but fails to bind avirulent plasmidless "P - " strains of the bacteria. The assay is rapid, safe, simple and highly effective.
Accordingly, it is an object of the present invention to provide a safe, simple, rapid and highly effective method for the detection of virulent P + strains of Y. enterocolitica.
Another object of this invention is to provide a method for the detection of and differentiation between virulent P + and avirulent P - strains of Y. enterocolitica which is more economical and less hazardous than prior known methods.
Still, another objective of this invention is to provide a method of quantifying the amount of virulent P + colonies in mixed cultures of Y. enterocolitica.
For purposes of the invention, the term "mixed culture" is used herein to designate cultures of Y. enterocolitica which contain virulent P + and avirulent P - strains of the bacteria. The abbreviation "CV + " and "CV - " is used herein to designate respectively strains of Y. enterocolitica which bind crystal violet dye and strains which fail to bind crystal violet dye.
In general, the method of the invention comprises treating colonies of Y. enterocolitica with an aqueous solution of CV dye for a period of time sufficient to allow the dye to bind to the virulent colonies of P + strains; subsequently removing the dye solution from the bacteria colonies; and thereafter, visually detecting, i.e. determining the presence or absence of, virulent P + strains of the colonies by their dark violet appearance in color due to binding with the dye. Avirulent P - strains, if any, present in the bacterial colonies are differentiated from the virulent P + strains by their white appearance in color due to failure to bind with the dye. Further, the invention method allows one to quantify the number of virulent and avirulent colonies of Y. enterocolitca in a mixed culture by simply counting the number of colonies which bind or fail to bind the dye.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the results of the CV binding assay of the invention on individual virulent and avirulent colonies of Y. enterocolitica strain GER (serotype 0:3) when cells were grown on Brain Heart Infusion (BHI) agar for 30 hours at 37° C.
FIG. 1A indicates virulent P + cells showing dark colonies.
FIG. 1B indicates avirulent P - cells showing white colonies.
FIG. 2 shows the results of CV binding assay of the invention on mixed virulent P + and avirulent P - colonies of Y. enterocolitica strain GER (serotype 0:3) when cells were grown on BHI agar for 30 hours at 37° C.
DETAILED DESCRIPTION OF THE INVENTION
Y. enterocolitica stock cultures may be grown under aerobic conditions at any incubation temperature and time satisfactory for growth and plasmid stabilization of the bacteria. Generally, the cultures are incubated at 5° C. to 25° C., most preferably 25° C., for about 17 to 18 hours.
The media useful for growth of the Y. enterocolitica stock cultures is any nutrient media suitable to support growth and plasmid stability of the bacteria cells. For optimum growth and plasmid stability, the preferred media is BHI broth. The pH of the nutrient media suitable for growth of the organism is about neutrality, i.e., pH 6.7 to 7.2.
In accordance with the binding assay of the invention, stock cultures of Y. enterocolitica are plated on a nutrient rich media and incubated at a time and temperature sufficient to express plasmid genes in the virulent P + strains which bind to crystal violet dye. The media may be any rich medium containing agar, preferably BHI agar. Colonies are preferably incubated at near 33° C. to near 40° C. for about 24 to 30 hours. For optimum results, colonies are incubated at about 35° C. to 37° C. for about 24 to 30 hours.
The CV dye solution useful in the invention assay consists of crystal violet dye dissolved in water, preferably distilled water. The aqueous dye solution may be used in any concentration sufficient to allow the virulent P + colonies of the bacteria to bind the dye but insufficient to allow the medium plates or avirulent P - colonies to bind the dye. Exemplary concentrations of the aqueous dye solution useful in the method of the invention is from about 50 μg/ml to 200 μg/ml. The preferred concentration is from about 80 to 90 μg/ml. For optimum results, the most preferred concentration is 85 μg/ml. Reduced concentrations may result in a low color intensity in P + cells while higher concentrations may produce high background color due to retention or binding of the dye on the media plates.
The CV binding assay of the invention is very rapid. Preferably, the culture plates are gently treated with the aqueous CV-dye solution for about 2 to 5 minutes. While low concentrations of dye solution may require additional time, it is desirable to perform all steps of the invention method within a maximum of 15 minutes since the distinct differentiation in pigmentation between the P + and P - colonies of the bacteria diminishes with time.
The following examples are intended to further illustrate the invention and not to limit the scope of the invention as defined by the claims.
EXAMPLE 1
Strains of Y. enterocolitica GER (serotype 0:3) were grown in BHI broth with agitation for 18 hours at 25° C. The cells were diluted to a concentration of 10 3 per ml and surface plated on BHI agar using a spiral plater. The plates were incubated for 30 hours at 37° C. Thereafter, the plates were gently flooded for 2 minutes with 8 ml of 85 μg/ml solution of CV dye in distilled water and the solution was decanted.
As shown in FIG. 1A, the P + strains bound CV producing dark violet CV colonies after the cells were grown for 30 hours at 37° C. The avirulent P - colonies did not bind CV but remained white in color, as indicated in FIG. 1B. Colony morphology of CV + and CV - strains examined by low magnification stereomicroscope were as follows: The CV + strains were small, convex, shiny, dark opaque colonies. The CV - strains were shiny, translucent, flat white colonies.
EXAMPLE 2
The CV binding technique as described in Example 1 was assessed using five P + strains of Y. enterocolitica and their P - derivatives representing four serotypes. P + and P - strains of Y. enterocolitica GER (serotype 0:3) were used for standardization of optimum conditions. CV + strains were examined for virulence and in vitro properties associated with virulence using the following tests:
ORAL INFECTION
Swiss Webster albino male mice (15-20 μg) were pretreated with 5 mg of iron-dextran. Virulence of P + and P - strains were determined by examining for diarrhea following oral infection of the mice.
CALCIUM DEPENDENCY
Calcium dependence was tested by growth on agar containing magnesium oxalate.
AUTOAGGLUTINATION
Autoagglutination was determined by the method as described in W. J. Laird et al. [J. Clin. Microbiol. 11: 430-432 (1980)], using Eagle's minimal essential medium supplemented with 10% fetal bovine serum.
HYDROPHOBICITY
Hydrophobicity was examined by the method as described in R. V. Lachica et al. [J. Clin. Microbiol. 19: 660-663 (1984)].
CONGO RED PIGMENTATION
The Congo red acid-morpholinepropanesulfonic acid pigmentation agar was prepared as described in J. K. Prpic et al. [J. Clin. Microbiol. 18: 486-490 (1983)].
Results were analyzed and recorded in Table I.
The results of Table I show the usefulness of the CV binding technique of the invention to detect virulent P + strains of Y. enterocolitica. As shown in Table I, all strains grown at 25° C. failed to bind CV dye while all P + strains of the different serotypes grown at 37° C. responded positively to the CV binding screening test. The corresponding isogenic P - strains of Y. enterocolitica did not bind to CV when grown at 37° C. but remained whitish in appearance. Further, CV + binding correlated with virulence as shown by oral infection causing diarrhea in iron-overloaded mice. Only CV + WA serogroup (0:8) evoked clear-cut mouse lethality along with diarrhea. Respecting other virulence-associated properties, CV + but not CV - strains displayed appropriate virulence-associated characteristics in every case except Congo red pigmentation. Both P + isolates and their P derivatives gave red colonies on a Congo red containing medium.
EXAMPLE 3
The CV binding method of the invention was used to quantitatively detect and differentiate P + strains from P - strains in mixed cultures of Y. enterocolitica.
The CV binding assay was as follows: Virulent P + cells of Y. enterocolitica GER (serotype 0:3) were mixed in various ratios with cells from avirulent P - GER strains of the bacteria. The mixed cultures were surface plated on BHI agar and thereafter were incubated and treated in accordance with the assay as described in Example 1. Results were recorded in Table II.
As indicated by FIG. 2, CV selectively bound the virulent P + strains as evidenced by dark colonies while failing to bind avirulent P - strains, colonies of which remain white in color. Calculated from the number of added P + cells, the data shown in Table II clearly indicates the ability of the CV binding method of the invention to differentiate and quantify the number of individual P + colonies present in mixed
TABLE I__________________________________________________________________________Virulence and virulence-associated properties of plasmid-bearing strainsof Y.enterocolitica and their plasmidless derivatives. CV binding Diarrhea.sup.b PlasmidStrain Serotype at 37° C. at 25° C. (Mice) CAD AA HP CRAMP Agar (40-45 Md)__________________________________________________________________________GER 0:3 + - + + + + + +GER-C - - - - - - + -EWMS 0:3 + - + + + + + +EWMS-C - - - - - - + -PT18-1 0:5,0:27 + - + + + + + +PT18-1-C - - - - - - + -O:TAC 0:TACOMA + - + + + + + +O:TAC-C - - - - - - + -WA 0:8 + - + + + + + +WA-C - - - - - - + -__________________________________________________________________________ .sup.b Fecal material consistency was liquid; diarrhea was observed on days 4, 5, 6, 7 followed by death on 8th day postinfection in case of serogroup 0:8; for three other serogroups (0:3, 0:5, 0:27 and 0:TACOMA) diarrhea was observed on days 5, 6, 7 postinfection with no death. CAD = Calcium dependency. AA = Autoagglutination HP = Hydrophobicity CRAMP = Congo red acidmorpholinepropanesulfonic acid pigmentation.
TABLE II______________________________________Effciency of CVbinding in mixed cultures of virulent and avirulent strains.EstimatedNumber of Colonies Number of Virulent ColoniesSample Avirulent Virulent Observed (%)______________________________________A 172 -- 0B 141 16 16 (100)C 131 31 29 (93)D 85 56 56 (100)E 72 98 92 (93)F 53 124 103 (83)G 22 130 124 (94)H -- 175 173 (98) Average 94.4%______________________________________ cultures of Y. enterocolitica. The average efficiency of the assay was about 94.4%.
The method of the present invention is advantageous in that microscopic observation is not necessary to distinguish between virulent and avirulent strains of Y. enterocolitica. Further, permanent records of the results may be easily retained using photographs. This is especially recommended since CV dye may diffuse through the medium and unbound P + colonies on standing over long periods of time. Additional advantageous features of the invention technique may be realized since the technique does not require special equipment and can be used effectively with large numbers of cultures.
It is understood that modifications and variations may be made to the foregoing disclosure without departing from the spirit and scope of the invention.
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A crystal-violet dye binding technique useful for the detection and differentiation of virulent plasmid-bearing strains of Yersinia enterocolitica. Virulent plasmid-bearing strains of the bacteria bind the crystal violet dye to form dark violet colonies while avirulent plasmidless strains fail to bind the dye and remain white in color. The method is simple, rapid, economical and highly reliable.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to a method and apparatus for facilitating the connection of tubulars using a top drive and is, more particularly but not exclusively, for facilitating the connection of a section or stand of casing to a string or casing.
[0003] 2. Description of the Related Art
[0004] In the construction of wells such as oil or gas wells, it is usually necessary to line predrilied holes with a string of tubulars known as casing. Because of the size of the casing required, sections or stands of say two sections of casing are connected to each other as they are lowered into the well from a platform. The first section or stand of casing is lowered into the well and is usually restrained from falling into the well by a spider located in the platform's floor. Subsequent sections or stands of casing are moved from a rack to the well centre above the spider. The threaded pin of the section or stand of casing to be connected is located over the threaded box of the casing in the well to form a string of casing. The connection is made-up by rotation therebetween.
[0005] It is common practice to use a power tong to torque the connection up to a predetermined torque in order to perfect the connection. The power tong is located on the platform, either on rails, or hung from a derrick on a chain. However, it has recently been proposed to use a top drive for making such connection.
[0006] Prior to the present invention, pipe handling devices moved pipes to be connected to a tubular string from a rack to the well centre using articulated arms or, more commonly, a pipe elevator suspended from the drilling tower.
[0007] The present invention provides an alternative to these devices.
SUMMARY OF THE INVENTION
[0008] Accordingly, a first aspect of the present invention provides an apparatus for facilitating the connection of tubulars, said apparatus comprising a winch, at least one wire line and a device for gripping a tubular the arrangement being such that, in use, the winch can be used to winch said at least one wire and said device to position a tubular below said top drive.
[0009] Further features are set out in claims 2 to 6.
[0010] According to a second aspect of the present invention there is provided a method of facilitating the connection of tubulars using a top drive and comprising the steps of attaching at least one wire to a tubular, the wire depending from the top drive or from a component attached thereto, and winching the wire and the tubular upwards to a position beneath the top drive.
[0011] According to a third aspect of the present invention there is provided an apparatus for facilitating the connection of tubulars using a top drive, said apparatus comprising an elevator and a pair of bails, characterised in that said elevator is, in use, movable in relation to said pair of bails.
[0012] According to a fourth aspect of the present invention there is provided: an apparatus for facilitating the connection of tubulars using a top drive, said apparatus comprising an elevator ( 102 ) and a pair of bails ( 103 , 104 ), characterised in that said elevator ( 102 ) is, in use, movable relative to said pair of bails ( 103 , 104 ).
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] For a better understanding of the present invention and in order to show how the same may be carried into effect reference will now be made, by way of example, to the accompanying drawings in which:
[0014] [0014]FIGS. 1 a to 1 e are perspective views of an apparatus in accordance with a first embodiment of the present invention at various stages of operation; and
[0015] [0015]FIGS. 2 a to 2 d are perspective views of an apparatus in accordance with a second embodiment of the invention at various stages of operation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0016] Referring to FIGS. 1 a to 1 e there is shown an apparatus which is generally identified by reference numeral 1 .
[0017] The apparatus 1 comprises a clamp 2 for retaining a tubular 3 . The clamp 2 is suspended on wires 4 , 5 which are connected thereto on opposing sides thereof. The wire 5 passes through an eye 6 in lug 7 which is attached to a spherical bearing in arm 8 of a suspension unit 9 at the point at which the arm 8 is connected to a hydraulic motor. The wire is connected to the hydraulic motor 10 in a corresponding manner. The suspension unit 9 is of a type which enables displacement of the tubular 3 when connected to a tool 17 (see below), relative to a top drive 13 , along a number of different axes. The wires 4 , 5 pass across the suspension unit 9 and over pulley wheels 11 which are rotatably arranged on a plate 12 . The plate 12 is fixed in relation to a top drive generally identified by reference numeral 13 . The wires 4 , 5 then pass over drums 14 to which the wires 4 , 5 are also connected. The drums 14 are rotatable via a hydraulic winch motor 15 .
[0018] In use, the clamp 2 is placed around a tubular below a box 16 thereof. The hydraulic winch motor 15 is then activated, which lifts the tubular 3 (conveniently from a rack) and towards a tool 17 for gripping the tubular 3 (FIG. 1 b ). The tubular 3 encompasses the tool 17 at which point the hydraulic winch motor 15 is deactivated (FIG. 1 c ). During this operation the elevator 18 is held away from the tool 17 by piston and cylinders 19 , 20 acting on bails 21 and 22 . The suspension unit 9 allows the hydraulic motor 10 and the arrangement depending therebelow to move in vertical and horizontal planes relative to the top drive 13 . The eyes 6 in lugs 7 maintain the wires 4 and 5 in line with the tubular 3 during any such movement. The tool 17 may now be used to connect the tubular to the tubular string. More particularly, the tool may be of a type which is inserted into the upper end of the tubular, with gripping elements of the tool being radially displaceable for engagement with the inner wall of the tubular so as to secure the tubular to the tool. Once the tool is secured to the tubular, the hydraulic motor 10 is activated which rotates the tool 17 and hence the tubular 3 for engagement with a tubular string held in a spider.
[0019] The clamp 2 is now released from the tubular 3 , and the top drive 13 and hence apparatus 1 is now lifted clear of the tubular 3 . The elevator 18 is now swung in line with the apparatus 1 by actuation of the piston and cylinders 19 and 20 (FIG. 1 d ).
[0020] The top drive 13 is then lowered, lowering the elevator 18 over the box 16 of the tubular 3 . The slips in the elevator 18 are then set to take the weight of the entire tubular string. The top drive is then raised slightly to enable the slips in the spider to be released and the top drive is then lowered to introduce the tubular string into the borehole.
[0021] Referring to FIGS. 2 a to 2 d there is shown an apparatus which is generally identified by reference numeral 101 .
[0022] The apparatus 101 comprises an elevator 102 arranged at one end of bails 103 , 104 . The bails 103 , 104 are movably attached to a top drive 105 via axles 106 which are located in eyes 107 in the other end of the bails 103 , 104 . Piston and cylinders 108 , 109 are arranged between the top drive 105 and the bails. One end of the piston and cylinders 108 , 109 are movably arranged on axles 110 on the top drive. The other end of the piston and cylinders 108 , 109 are movably arranged on axles 111 , 112 which are located in lugs 113 , 114 located approximately one-third along the length of the bails 103 , 109 .
[0023] The elevator 102 is provided with pins 115 on either side thereof and projecting therefrom. The pins 115 are located in slots 116 and 116 g. A piston 117 , 118 and cylinder 119 , 120 are arranged in each of the bails 103 , 104 . The cylinders are arranged in slot 121 , 122 . The piston 117 , 118 are connected at their ends to the pins 115 . The cylinders 119 , 120 are prevented from moving along the bails 103 , 104 by cross members 123 and 124 . A hole is provided in each of the cross members to allow the pistons to move therethrough.
[0024] In use, a tubular 125 is angled from a rack near to the well centre. The tubular may however remain upright in the rack. The clamp 102 is placed around the tubular below a box 126 (FIG. 2 a ). The top drive is raised on a track on a derrick. The tubular is lifted from the rack and the tubular swings to hang vertically (FIG. 2 b ). The piston and cylinders 108 , 109 are actuated, extending the pistons allowing the bails 103 , 104 to move to a vertical position. The tubular 125 is now directly beneath a tool 127 for internally gripping and rotating the tubular 125 (FIG. 2 c ). The pistons 117 , 118 and cylinders 119 , 120 are now actuated. The pins 115 follow slot 116 and the clamp 102 moves upwardly, lifting the tubular 125 over the tool 127 (FIG. 2 d ). The tool 127 can now be actuated to grip the tubular 125 .
[0025] At this stage the elevator 102 is released and the top drive 105 lowered to enable the tubular 125 to be connected to the string of tubulars in the slips and torqued appropriately by the top drive 105 .
[0026] The pistons 117 , 118 and cylinders 119 , 120 are meantime extended so that after the tubular 125 has been connected the top drive 105 can be raised until the elevator 102 is immediately below the box. The elevator 102 is then actuated to grip the tubular 125 firmly. The top drive 105 is then raised to lift the tubular string sufficiently to enable the wedges in the slips to be withdrawn. The top drive 105 is then lower to the drilling platform, the slips applied, the elevator 102 raised for the tubular 125 and the process repeated.
[0027] While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.
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An apparatus for facilitating the connection of tubulars, said apparatus comprising a winch ( 15 ), at least one wire line ( 4, 5 ), and a device ( 2 ) for gripping the tubular ( 3 ), the arrangement being such that, in use, the winch ( 15 ) can be used to winch said at least one wire ( 4, 5 ) and said device ( 2 ) to position a tubular ( 3 ) below said top drive.
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FIELD OF THE INVENTION
[0001] The invention relates to the field of alkaline pulping.
BACKGROUND OF THE INVENTION
[0002] Among the chemical pulping methods, alkaline cooking processes and especially kraft cooking are dominant in the production of cellulose or chemical pulp because alkaline cooking provides pulp fibers which are stronger than those from any other commercial pulping process. The lignocellulosic material, typically chopped into wood chips, is treated in either batch or continuous digesters.
[0003] In chemical pulping processes as alkaline cooking, the chemical reactions with wood components are heterogenous-phase border reactions. To ensure uniform reactions, it is vital that all fibers in the wood get their proper share of chemicals and energy. Non-uniformity occurs when these criteria are not fulfilled and this may result in a larger amount of unfiberized wood (rejects) in the final pulp, discolored pulp, lower final yield and impaired bleachability and paper properties. The objective of chemical pulping is to remove lignin so that the fibers can separate. Ideally, each fiber should receive the same amount of chemical treatment for the same time at the same reaction site. This means that chemicals and energy must be transported uniformly to reaction sites throughout each chip. There are two major stages where this can happen; (1) the impregnation phase where chips are saturated with chemical-containing liquid before delignification reactions begin and (2) the continuous movement of chemicals to the reaction sites during the cooking phase. Chip dimensions are of major importance in this context. The longer, wider and especially the thicker the chips are, the longer is the transportation distance to the centers of the chips
[0004] Pores inside fresh wood chips are also partly filled with liquid and partly with air. The ratio is, among others, determined by the moisture content or dry content of wood. The air should be removed from the chips before they can be fully impregnated by cooking liquor. This is usually done by pre-steaming the chips.
[0005] As cooking proceeds, reactive ions must diffuse into the chips. If the transportation distance is too long and rate of transportation too slow, the chemicals may be completely consumed before they can reach the chip centers, resulting in non-uniform cooking. Thus, in cooking there is a critical balance between the rate of ion transportation, wood porosity, chip dimensions and the rate of chemical reaction. E.g. raising the temperature increases the rate of transportation, but the rate of reaction increases still faster. On an average, long and thick chips will not delignify as fast as short and thin chips when the same cook parameters are used. In conventional batch cooks, long and thick chips generate more screening rejects than short and thin chips and shorter cooks and higher cooking temperatures aggravate the effect. The higher the cooking temperature, the shorter is the required time to a certain delignification degree and the higher is the rate difference between delignification reaction and ion transportation. Thus it seems that cooking uniformity would require that chips should be small and thin enough and that the size variation in the chip furnish should be as narrow as possible. However, in practice many other important parameters as e.g. chipping parameters, chipping capacity, fiber cutting, fiber length, paper properties, the bulk density of the chip column, the permeability of the chip column, produced saw dust and pin chips amounts and plugging of digester screens has also to be taken into account. Saw dust is material passing through a 3 mm hole screen; pin chips is material that passes through 7 mm hole screens but is retained on a 3 mm hole screen.
[0006] It has also been proposed that the rate of heating influence the result. A shorter heating period requires a smaller chip size to ensure sufficient uniformity, and it has been demonstrated that shredding of the chips will reduce the screening when using very rapid cooks (cycle-to-cycle) at high temperatures, and almost no heating period. Such conditions, i.e. fast heat-up and high temperatures prevail in certain types of continuous digesters as saw dust and pin chips digesters. In the Kamyr type of continuous digester as well as in most batch digesters, slow cooking, i.e. low rate of reaction, long heating period and lower maximum temperature, allow a more uniform cooking also of ordinary mill size chips. As both shredding and chipping to smaller size will affect fiber length, pulp quality and efficiency of operation, it is desirable to provide conditions that allow the normal industrial chip size.
[0007] For processing ordinary mill size chips, it has been proposed that cooking non-uniformity can be reduced and perhaps eliminated by proper chip manufacturing and screening, proper impregnation and sufficiently low cooking temperature. Thus low rate of chemical reactions and long cooking stage in combination with impregnation and uniform chips.
[0008] In a conventional alkaline batch cooking process, wood chips are fed to a digester and cooking liquor is added. The chips can be steam treated before, during or after chip filling to pre-heat the chips and remove air. The pressure is about atmospheric after liquor addition. When chips and liquor have been added, the cook is immediately started by introduction of heat either indirectly or directly by steam. Impregnation occurs during heating. The cook itself consists of a heating period and an “at pressure” period. Typical heat-up times and at pressure times are 60 to 150 minutes and 60 to 120 minutes, respectively. Typical sum of heat-up and at pressure times is about 150 minutes. At the conclusion of the cook lo when the delignification has proceeded to the desired reaction degree, a blow valve in the digester is opened and the contents of the digester are discharged into a blow tank, as the hot liquor in the digester flashing into steam and forces the cooked pulp out of the digester. The cooked material is cooled and defiberized.
[0009] The difficulty with conventional batch cooking is the non-uniform and poor quality of the pulp, high energy consumption and environmental concerns. Therefore, one of the most important objectives has been the attempt to improve the efficiency of the cooking process and to improve the properties of the resulting pulp and the uniformity, especially in relation to above mentioned conventional process. Continuous flow processes and displacement batch processes have therefore been developed.
[0010] Displacement batch pulping processes were developed in the 80's, originally for the sake of energy economy. Following a batch cook, the black liquor was recovered, divided into fractions according to temperature and chemical content, stored and introduced into a digester charged with fresh lignocellulosic material in order to transfer the heat of the completed cook to a subsequent cook. The total duration of the black liquor impregnation stage in batch displacement processes is typically below 30 min at temperatures below 100° C. Heating is carried out by displacement with a black liquor having a higher temperature than the impregnation liquor. Following these initial stages, white liquor is introduced, and a main cooking stage follows. Typically, the total duration of the hot liquor fill stage, temperature adjustment and the cooking stage is in the range 95-120 min. Practical experience shows that the process becomes chemical transportation rate limited at total heating and cooking times below about 95 min.
[0011] Several variations of the batch displacement cooking process have been developed to optimize utilization of cooking chemicals and to handle variations in raw material, where it may be advantageous to adjust the composition and/or sequence of pretreatment liquors. In addition to energy economy, adjustment possibility, pulp quality and flexibility are advantages when displacement batch cooking processes are used. On the other hand, these processes require a significant amount of tanks and piping to handle the various liquors involved. As the trend is towards closed cirquits and lower emissions from plants, accumulation problems may also occur.
[0012] In contemporary continuous processes, typically referred to as the Kamyr type, energy savings are achieved by pre-heating the chips with steam obtained from flashing the hot black liquor. In the pre-steaming of the chips, chips are preheated and air is removed from the chips to facilitate later liquor impregnation. In continuous cooking, the chip impregnation zone typically involves 30-60 min or shorter chip retention at a temperature of 115-130° C. and a high pressure to enhance the pre-impregnation of the chips and the ion transportation into the chips. Since penetration rates increase with increased pressure, impregnation stages operate at pressures that greatly exceed the liquor saturation pressure at the specified temperature, i.e. typically greater than 10 bars operating pressure for impregnation temperatures of 115-130° C. Subsequent to impregnation, the chips are heated directly in a vapor phase and/or in several liquor heating circuits to full cooking temperature, and then typically cooked for at least 1.5-2.5 hours in a concurrent cooking zone at temperatures below 165° C. Practical experience suggests that the process becomes chemical transportation rate limited at cooking times below about 1.5-2.5 hours and temperatures above 165° C. Therefore, typical cooking temperatures are between 150-165° C. but even cooking temperatures of 140-150° C. can also occur, see for example international patent application WO 98/35091. Thus, a minimum of 1.5-2.5 hours of cooking is required. In addition, subsequent to the concurrent cooking zone, a countercurrent zone, typically referred to as the hi-heat zone, usually follows for 2-4 hours at temperatures of 130-160° C. Contemporary continuous cooking as e.g. ITC, EMCC and Lo-solids cooking retains the cooking temperature, typically 150-160° C., all through the countercurrent zone, i.e. enlarging the cooking zone to the counter-current zone. These modern digesters have thus a total cooking zone of about 240-360 minutes. For the countercurrent zone, washing filtrate is pumped into the bottom of the vessel. The vessel bottom is also a blow dilution and cooling zone. Discharge temperature is typically 85-90° C.
[0013] The continuous processes offer, compared to conventional batch digesters: more space efficiency, less installed power, lower volumes of inlet streams and outlet stream, steady-state operation vs. batch fill and discharge cycles, energy efficiency, lower environmental impact and a first stage of brownstock washing.
[0014] However, it is found that while the typical continuous processes have the aforesaid advantages the pulp obtained has a number of properties, e.g. strength and uniformity of the pulp, which are inferior to e.g. pulp produced under well-controlled laboratory conditions. The continuous process still lacks sufficient impregnation and this has to be compensated by lower reaction temperatures and long retention times in the digester. This leads to expensive, large-size and huge digesters designed for high pressures and temperatures. The scale of contemporary digesters, typically of the type Kamyr, at higher production levels also causes mass-transfer problems in liquid circulations and displacement, which further is compensated by longer retention times and lower cooking temperatures.
[0015] Impregnation theoretically requires small chips, but modern continuous digesters are based on the principle of maintaining sufficient liquid circulation and a good displacement efficiency. This calls for chip properties that are in conflict with some of the basic requirements for ensuring uniform delignification. Thus, a large chip size must be used, which leads to inferior impregnation and further longer retention times in cooking and expensive technology. Thus, the pulp maker has been trapped by his own technology. It is stated, that the 30-60 min retention time at 115-130° C. in impregnation zones of continuous mill digesters could never provide a completely uniform distribution of cooking chemical for all chips (mill chips) before the start of bulk delignification.
[0016] In Swedish patent application 9602016-9, it is suggested that the way the chips are treated before continuous kraft cooking is disadvantageous for the strength of the pulp. It is proposed that the pre-impregnation at 110-130° C. in e.g. Kamyr continuous digesters is unfavourable and the chips should instead be cold impregnated. During impregnation it would only be necessary to have enough alkali present to neutralize possible by-products, in order to prevent formation of acidic regions that can damage the fiber properties. The alkali required during cooking can consequently be added after the pretreatment, and/or during cooking, i.e. a high alkali level is not required during impregnation. A pulping process is disclosed which comprises so-called “cold impregnation” as its main feature. A temperature of about 80-110° C. is specified, the time period being unlimited. However, an optimum of 2-3 hours is suggested. Pressure may be used in order to compress gas bubbles and cause sinking of the chips. The theory behind the cold impregnation stage is, that acid-generating processes within the chips shall be suppressed until the chips are filled with alkali sufficient to neutralize any acid released when reaction commences at higher temperatures, and the impregnation step is defined as resulting in “an alkali concentration sufficient to neutralize all acid produced”.
[0017] The proposed process preferably uses a conventional continuous digester like MCC, EMCC or Lo-solids digester. Thus, the retention times in the cooking stage are in the order of several hours, typically around 2-5 hours. In addition, the figures of the application show a residence time in the impregnation stage approximately of the same order as in the cooking stage. However, it is found that while the proposed continuous processes have pulp strength advantages, the cooking stage still has a long retention time and low reaction temperature. This requires huge and expensive digesters designed for, from a technical point of view, high pressures and temperatures.
[0018] In U.S. Pat. No. 3,215,588, and in a paper titled “Rapid alkaline cooking”, Pulp and Paper Magazine of Canada, No 7, pages T-275-T-283, a process is disclosed wherein an extended impregnation stage is utilized followed by a rapid cooking stage. Chip impregnation takes place at a pressure in excess of 10 bar, using cooking liquor. Subsequently, the chips are fed into a continuous digester having a steam zone where the chips are rapidly heated to 170-185° C. and thus cooked before entering a liquid zone where gradual cooling takes place prior to discharge. The paper teaches that the total cycle including impregnation is in the range of 30 to 45 minutes, mostly using impregnation temperatures of 130-150° C. The process results in pulp relatively low in lignin, having good bleachability according to the standards of the time, and the process is rapid due to the pressurized impregnation stage and the short heating stage. However, the screen rejects content is high and the strength reduced in comparison with pulp produced by conventional methods of the period. These disadvantages are addressed in U.S. Pat. No. 3,644,918, which introduces water saturation of the chips prior to impregnation. By using water-saturated chips, according to U.S. Pat. No. 3,644,918, it is possible to obtain complete and uniform impregnation at atmospheric pressure at e.g. 90° C. within a period of the order of 60 minutes. The whole amount of cooking liquor is added in the impregnation stage. Screen rejects are negligible, the yield is higher and the pulp shows better properties than according to U.S. Pat. No. 3,215,588. However, the authors have found that this process also lacks efficiency, since the water saturation of the chips increases the evaporation demand in the recovery cycle, the reject levels are high and the screened yield is low.
[0019] Thus, development of both batch and continuous cooking technology has been characterized by improvements in various fields, e.g. energy efficiency. However, very little attention has been paid to important issues as how to really utilize both “the front-end” and “back-end” of the cooking process to simplify it, retain flexibility and also to improve the pulp quality. The failure to consider these issues has to a great extent been responsible for the development of larger and larger equipment as well as lowering the flexibility of the process and causing lower pulp quality. The development of rapid cooking has failed to recognize the conditions, which are required to economically produce high-quality pulp.
SUMMARY OF THE INVENTION
[0020] According to the present invention, an improved, alkaline batch cooking process is provided, wherein the raw chip material is preheated and air purged, and impregnated with a liquor at a temperature no higher than the boiling point at atmospheric pressure of the impregnation liquor, at retention times of more than 60 minutes. Liquors including fresh cooking liquor are added to result in a concentration in the range from about 0.5 to 2.2 mol/l as OH − ions; preferably said concentration is about 0.5 to 1.5 mol/l as OH − /l ions; more preferably said concentration is about 0.75 to 1.5 mol as OH − /l ions. A liquid-to-wood ratio in the range of 3 to 10 m 3 /t odw (m 3 per ton oven dry wood) is to be maintained during the impregnation step; preferably said ratio is in the range of 3 to 6 m 3 /t odw.
[0021] The impregnated material is subsequently transferred to a batch digester and heated to a temperature T 2 of at least about 150° C., preferably in not more than 40 min (t 2 ), after which follows a cooking stage at a time t 3 with a maximum temperature T 3 of no more than 185° C., and a liquid-to wood ratio of at least 2.5 m 3 /t odw during a substantial part of the heating and cooking steps. The total of t 2 and t 3 shall not exceed 90 min. Fresh cooking liquor is added during the heating step, the cooking step or both. After the cooking step, the delignified material is cooled to a temperature where significant cooking reactions no longer occur.
[0022] In practice, a temperature decrease to about 140° C. is sufficient to end the cooking step. Preferably, the time t 1 for impregnation is above 120 min, and the temperature T 1 in the range from 70° C. to the boiling point at atmospheric pressure of the impregnation liquor. Preferably, the total of t 2 and t 3 is less than 80 min. More preferably, the total of t 2 and t 3 is less than 70 min. Even more preferably, the total of t 2 and t 3 is in the range 10-60 min. Further, the liquid-to wood ratio during a substantial part of the heating and cooking steps is preferably at least 3 m 3 /t odw; more preferably, it is at least 3.5 m 3 /t odw.
[0023] According to the invention, batch digesters over 10 m 3 are used. The heating and cooking time total in minutes may be expressed in relation to the digester volume V in m 3 as follows:
t 2 +t 3 ≦(0.09 V+ 63) min when V≧ 100 m 3 ,
t 2 +t 3 ≦70 min when V is between 10 and 100 m 3 .
Preferably, t 2 +t 3 ≦(0.09 V+ 53) min when V≧ 100 m 3 , and
t 2 +t 3 ≦60 min when V is between 10 and 100 m 3 .
More preferably, t 2 +t 3 ≦(0.09 V+ 43) min when V≧ 100 m 3 , and
t 2 +t 3 ≦50 min when V is between 10 and 100 m 3 .
Even more preferably, t 2 +t 3 ≦(0.09 V+ 33) min when V≧ 100 m 3 , and
10 min≦t 2 +t 3 ≦40 min when V is between 10 and 100 m 3 .
[0024] The heating time of a batch reactor is heavily dependent on size. A batch reactor of industrially significant size cannot be considered as a whole with regard to temperature, but each region within the reactor should ideally have the same temperature history. In a liquid displacement reactor equipped for bottom-to-top displacements, the material at the bottom reaches hot liquor displacement temperature long before the material at the top, but is correspondingly cooled earlier. Thus, the various parts of the digesters experience the same temperatures during approximately the same periods, but at a given point of time, the temperature may be different in various regions of the batch reactor.
[0025] According to the present invention, the heating step during period t 2 is preferably carried out by means of liquid displacement, whereby the amount of heat delivered to each region of chips is essentially uniform throughout the digester. The cooking step during period t 3 is preferably carried out by liquor exchange as e.g. liquid circulation or displacement.
[0026] According to the present invention, the cooling step is preferably carried out by means of liquid displacement.
[0027] The average dry-solid of the material entering the impregnation stage is preferably over 40%; more preferably said dry-solid is over 45%.
[0028] Preferably, impregnation takes place at low pressure, for the present purposes defined as up to 5 bar. Thus, low pressure equipment may be used, which saves investment costs. Use of pressure may be required to ensure sinking of the chips in the liquid phase. If high pressure equipment is installed, it may be utilized as expedient.
[0029] As raw material for the process according to the invention, industrial wood chips are used. These commonly have an average length above 10 mm, typically 15-35 mm, and an average thickness above 2 mm, typically 3-7 mm.
[0030] According to one aspect of the present invention, a digesting system is provided for carrying out the process of the invention. The digesting system comprises at least one impregnation vessel, batch digesters in fluid communication with the impregnation vessel; transfer lines between the impregnation vessel and the bottom of each digester for transporting the impregnated material to the digester; a separator, comprising a withdrawal space, disposed in connection with each digester for separating a transport liquid from the impregnated material; first return lines attached to each separator to conduct the transport liquid from the separator back to the transfer lines; second return lines connected to the first return lines and to the impregnation vessel for transferring a portion of the transport liquid to an inlet of the impregnation vessel; and a supply line connected to an inlet of the impregnation vessel. Due to the relation between the time periods for impregnation and cooking, the volume V of the impregnation vessel is larger than 1.5 times the volume of each digester, preferably larger than 3 times the volume of each digester, more preferably larger than 5 times the volume of each digester.
[0031] The above process has given excellent results as shown in the examples, and it is a significant process simplification. The differences compared to prior art batch processes are the unique combination of:
[0032] low temperature during impregnation, which enables low-pressure and -temperature equipment in impregnation, and long retention times, i.e. over 60 min, in a separate stage outside the digester
[0033] alkali concentration of 0.5-2.2 mol OH − /l of added liquor in impregnation
[0034] a short heating and cooking stage making possible a lower volume of cooking equipment
[0035] liquor-to-wood ratio over 2.5 m 3 /t odw and fresh alkali addition in heating or cooking stage or both
[0036] different pressures in the impregnation and cooking stages, which enables simpler equipment for low-pressure impregnation and a lower volume of high-pressure equipment, i.e. batch digesters.
[0037] This results in process simplification and great flexibility. The batch cycle is significantly shortened compared to prior art processes. Experimental results show that the process gives high yield, improved bleachability and at least equal quality compared to prior art methods.
[0038] The specific effective alkali concentrations, temperatures and times used in a process according to the invention are dependent on the type of wood and the purpose of the product. Hardwood cooking generally requires lower maximum cooking temperatures than softwood cooking. Pulp for unbleached products also normally require lower cooking temperatures than for bleached products. The impregnation time depends mainly on the type of chips and raw material. Material hard to impregnate, and consequently requiring longer times, may consist of long and thick chips, or have a large proportion of low-porosity material. The type of equipment and the space available are other factors.
DISCLOSURE OF THE INVENTION
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] [0039]FIG. 1 shows schematically the time-temperature profile of prior art conventional batch cooking,
[0040] [0040]FIG. 2 shows schematically the time-temperature profile of prior art displacement batch cooking,
[0041] [0041]FIG. 3 illustrates schematically the time-temperature profile of prior art continuous cooking of the Kamyr type,
[0042] [0042]FIG. 4 illustrates schematically the time-temperature profile of an embodiment of the invention,
[0043] [0043]FIG. 5 is a schematic representation of the tank farm required combined with a flowchart showing an embodiment of the invention and the various liquor streams occurring during the production cycle,
[0044] [0044]FIG. 6 is a representation corresponding to FIG. 5 showing an alternative embodiment of the invention,
[0045] [0045]FIG. 7 is a representation corresponding to FIG. 5 showing a further alternative embodiment of the invention,
[0046] [0046]FIG. 8 shows the brightness achieved versus consumption of active chlorine in pulps prepared using the conditions set forth in Table 1,
[0047] [0047]FIG. 9 shows the brightness as a function of viscosity of pulps prepared according to the examples in Table 1,
[0048] [0048]FIG. 10 shows the active chlorine consumption against bleached yields in the examples according to Table 1, and
[0049] [0049]FIG. 11 shows the reject percentage as a function of impregnation time in pulp cooked to two kappa numbers according to the invention.
DETAILED DESCRIPTION
[0050] FIGS. 1 to 4 show the temperature profiles of prior art pulping methods compared to that of the present invention. Referring now to FIG. 1, which shows the temperature curve against time in a conventional batch cook, region 1 of the curve represents the heat-up phase, region 2 illustrates cooking at about the maximum temperature and region 3 illustrates the discharge and cooling of the conventional batch digester.
[0051] Typically, the duration of region 1 is 60 to 150 minutes, and that of region 2 60 to 120 minutes. The sum of region 1 and 2 is typically about 150 minutes.
[0052] In FIG. 2 showing the corresponding curve of a prior art displacement batch process, region 5 represents the impregnation phase, region 6 the hot liquor fill phase, i.e. hot black liquor treatment and hot white liquor charge, region 7 represents the temperature adjustment phase, usually carried out by circulating the digester content and heating, region 8 illustrates the cooking phase at cooking temperature. Region 9 represents the displacement with cool wash liquid and region 10 represents the cold discharge.
[0053] Typically, the duration of region 5 is typically about 30 minutes, but it can be 10 to 40 minutes depending on digester size, at a temperature below 100° C. Region 6 is typically about 30 minutes (can be 15 to 40 minutes depending on digester size). Regions 7 and 8 are typically 65 to 100 minutes. Thus, regions 6 , 7 and 8 together typically represent 95 to 130 minutes. Region 9 is typically 45 minutes (can be 20 minutes to 60 minutes depending on, among other factors, digester size). The stages of regions 5 - 9 occur in the same batch equipment.
[0054] In FIG. 3, illustrative of a prior art continuous process, region 11 represents the impregnation phase, region 12 represents heating and region 13 represents a cooking phase, which can occur in both concurrent and countercurrent modes. Region 14 represents displacement and cooling of the cooked material before discharge from the digester. Region 11 is typically 30 to 60 minutes or shorter at a temperature of 115-130° C. Regions 12 and 13 are over 90 minutes, typically 240 to 360 minutes.
[0055] [0055]FIG. 4 shows the advantageous temperature profile of the present invention. Region 20 represents the impregnation phase, which as can be seen is substantially extended relative to processes presently in use. Region 21 represents the heating-up phase. Region 22 represents the short reaction time and region 23 the cooling of the cooked material before discharge from the digester. Between regions 20 and 21 , feeding of the pre-impregnated material to the batch digester takes place.
[0056] [0056]FIG. 5 is a schematic representation showing the various tanks used in an embodiment of the invention, and a flowchart of the process together with the liquor streams occurring and their relation to the tanks. Wood chips are pre-steamed (point 1 ) and charged into the impregnation vessel. The chips can preferably be pre-heated to a temperature of 95-110° C., the retention time at that temperature being preferably 5-40 min. The transfer method and equipment between the presteaming phase and the impregnation vessel depends on the counter-pressure in the impregnation stage. The residence time of the impregnation stage (point 2 ) is at least 60 minutes. It can be significantly longer, depending on the available size of equipment. Longer times or impregnation times of more than about 24 h may be used for example when combining the impregnation stage with chip storage between the chipping unit and the cooking plant The impregnation time rarely exceeds 120 hours in the same equipment The impregnation equipment may be a down-flow vertical vessel or a horizontal conveyer type vessel with at least one inflow and at least one outflow point for the material, known to the person skilled in the art. Installed continuous digester vessels can be used e.g. when upgrading an existing plant. When using longer retention times, the impregnation device can be considered to be of the chip silo vessel type. Several vessels can be used in series or in parallel. According to the invention, the impregnation vessels are preferably dimensioned for a low pressure, i.e. pressure in the area from about atmospheric to 5 bar. Atmospheric conditions can be used. High-pressure equipment (over 5 bar design pressure) can be used when for example upgrading a plant to a method according to the invention. Liquor A is added to the stage. The liquor contains fresh alkali (point WLimp) and spent liquor from tank 4 . The amount may be, for example, 30 per cent or more of the total fresh alkali to be added calculated as total titrable alkali (TTA) per charged unit of wood, but additional fresh alkali is invariably added in the cooking stage. Spent liquor (from tank 4 ) is added as needed, recycled from e.g. a subsequent liquor-separation stage. The effective alkali concentration of the added liquors is 0.5-2.2 mol OH − /l; preferably, in the range 0.5-1.5 mol OH − /l; more preferably, in the range 0.75-1.5 mol OH − /l.
[0057] The impregnation liquor A is a mixture of fresh alkali and spent liquor. The fresh alkali and spent liquor can be added together at one addition point, or in sequences during the impregnation. Spent liquor can be added first, and then fresh alkali is added and some spent liquor withdrawn. Fresh alkali can also be added first and then spent liquor. Parts of spent liquor and fresh alkali can also be added first, and then fresh alkali is added together with some withdrawal of spent liquor. The fresh alkali used can be both caustisized liquor, normally referred to as white liquor, and uncaustisized liquor, normally referred to as green liquor, or also derivates of the above mentioned liquors, e.g. a mother liquor from crystallization of sodium carbonate from green liquor. The temperature of liquor A may require adjustment to hold the preferable temperature between 70° C. and its atmospheric boiling point.
[0058] Impregnated material is transferred from the impregnation reactor to the batch digester via a transfer system (points 3 and 4 ), which may be one of various combinations of discharge systems in the outlet part of the impregnation vessel and feeding technology known to the person skilled in the art. The system is supplied with liquor A 1 as required e.g. for dilution. Transfer systems to be used are for example pumps, chamber feeders (e.g. of the high pressure (HP) feeder type), screws, scrapers and injectors etc., and combinations therof, known to the person skilled in the art. Preferably, the digester is charged hydraulically by e.g. pumping from the bottom. Other methods, e.g. charging from the digester top after liquid separation, may also be used. Surplus liquor is removed at A 1 from for example the digester screen girdle, and is conducted to tank 4 .
[0059] Following chip charge, hot black liquor B from tank 1 and hot white liquor C from tank 3 are charged in a hot liquor fill stage (point 5 ), initially displacing liquor A 2 to tank 4 and then, as the temperature rises above boiling point, D to tank 2 . The temperature is adjusted by means of circulation-based direct or indirect steam heating or direct steam heating of the digester (point 6 . 1 ). In accordance with the invention, at the end of the cooking stage (point 6 . 2 ), the effective alkali concentration of the cooking liquor can be 0.05-0.7 mol OH − /l, preferably in the range 0.1-0.5 mol OH − /l. Cooking is completed, and the batch is cooled by displacing the cooking liquor with cooler liquor (point 7 ), e.g. wash filtrate E from tank 5 , possibly containing also liquor from tank 4 . Displaced liquor is divided according to temperature and chemical content into fractions B 1 and D 1 , to tanks 1 and 2 respectively. When the temperature has decreased below about 100° C., the digester is discharged (point 8 ), preferably by pumping using additional filtrate F from tank 5 as required.
[0060] In accordance with the flow balance, flow G, filtrate from the wash plant, may be used to dilute the white liquor, which is conducted to tank 3 while being heated by black liquor from tank 2 .
[0061] [0061]FIG. 6 is analogous to FIG. 5, but no circulation heating is used in the digester, which consequently requires no heating circuit piping. Instead, the digester heating takes place using hot liquor displacement (point 5 ), whereby the temperatures of black liquor B and white liquor C are preferably adjusted by heat exchange before introduction into the digester. Liquors D and B displaced during the hot displacement stages are conducted to tanks 2 and 1 , respectively, depending on temperature and/or chemical content. According to this embodiment of the present invention, also cooking is carried out by displacement (point 6 ).
[0062] [0062]FIG. 7 shows an embodiment where heating occurs by direct or indirect steam heating to the digester circulation or direct steam heating of the digester (point 6 . 1 ). Other differences are pressurized blow of the digester content at the end of cooking (point 8 ).
[0063] Table 1 shows the results of, on the one hand, comparative cooking experiments (1-4) using various typical conditions for prior art continuous and batch cooking, and on the other hand experiments (5-11) using conditions according to the present invention.
Example 1 2 3 4 5 6 7 Co king Prior-art Prior-art Prior-art Prior-art Invention Invention Invention Continuous Continuous Continuous Batch lab lab lab mill mill lab lab Impregnation Temperature, ° C. 90 80 95 95 95 EA mol OH − /l 3.05 0.3 1.25 1.25 1.25 Time, min 60 30 4320 60 60 Pressure, bar 0 5 0.5 0.5 0.5 Liquor-to-wood ratio m 3 /ft 4 5 4.6 Heating and C oking EA of added liquor, mol OH − /l 0.54 0.69 0.62 Liquor-to-wood ratio, m 3 /t 1.6 5 3.5 3.5 3.5 Heat-up, min 7 50 15 15 15 Heat-up + cooking time, min 29 91 25 25 25 Max cooking temperature, ° C. 175 160 169 176 169 End-of-cook residual EA, mol OH − /l 0.23 0.28 0.22 0.24 Unbleached pulp Kappa Number 15.2 15.4 19.8 20.3 16.4 17.8 26.9 Brightness, ISO % 31.1 32.1 41.7 41.8 47.2 44.8 39.7 Total Yieid, % nd nd 54.2 55.4 54.3 55.3 57.2 Total Reject, % nd nd 2.66 0.97 0.12 0.88 1.2 Screened yield, % nd nd 51.5 54.4 54.2 54.8 56.3 Oxygen delignification Time, min 60 20/60 nd 60 30/120 30/120 30/120 Temp, ° C. 100 90/100 nd 100 90/110 90/110 90/110 NaOH charge, kg/odt 15 10 nd 18 25 25 35 Oxygen pressure, Mpa 0.5 0.8/0.5 nd 0.6 0.8/0.5 0.8/0.5 0.8/0.5 Residual Ph 12 9.7 nd 11.8 11.7 11.4 11.8 Kappa Number 9.2 9.7 nd 12 8.6 8.5 11.3 Kappa reduction, % 39 37 nd 41 48 52 58 Viscosity, dm 3 /kg 895 908 nd 1065 1014 896 979 Brightness, % ISO 54.7 50.4 nd 59.6 72.0 71.4 68.0 ECF Bleaching Stages used D(EOP)(DnD) D(EOP)DnD nd D(EOP)DnD D(EOP)DD D(EOP)DD D(EOP)DD Tot. conc. Act Cl, kg/odt 42.8 41.3 nd 38 13.8 17.5 18.7 Tot. conc. Act. Cl mult 0.46 0.43 nd 0.31 0.17 0.22 0.17 Brightness, % ISO 90.5 91 nd 92.0 92.0 91.7 91.5 Viscosity, dm 3 /kg 838 779 nd 800 922 818 871 Bleached yield, % 52.0 52.0 52.3 52.6 PFI beating results Brightness, % ISO nd 91.0 nd 90.5 92.0 91.7 91.5 SR 30 Tensile index, Nm/g nd 82.8 nd 83.2 91.9 92 92.7 Tear index, mNm 2 /g nd 10.8 nd 9.0 11.1 10.6 10.7 Examples 8 9 10 11 Co king Invention Invention Invention Invention lab lab lab lab Impregnation Temperature, ° C. 95 95 95 95 EA mol OH − /l 1.25 1.25 1.25 1.25 Time, min 180 4320 60 60 Pressure, bar 0.5 0.5 10 10 Liquor-to-wood ratio m 34.6 4.6 4.6 46 /ft Heating and C oking EA of added liquor, mol OH − /l 0.64 0.41 0.62 0.64 Liquor-to-wood ratio, m 3 /t 3.5 3.5 3.5 3.5 Heat-up, min 15 15 15 15 Heat-up + cooking time, min 25 25 25 27 Max cooking temperature, ° C. 168 160 174 168 End-of-cook residual EA, mol OH − /l 0.27 0.31 0.24 0.29 Unbleached pulp Kappa Number 30.6 32.5 19.7 27.4 Brightness, ISO % 42.6 42.0 42 40 Total Yieid, % 57.6 57.5 54.5 56.5 Total Reject, % 1.16 1.23 0.96 1.4 Screened yield, % 56.4 56.3 53.5 55.1 Oxygen delignification Time, min nd nd nd nd Temp, ° C. nd nd nd nd NaOH charge, kg/odt nd nd nd nd Oxygen pressure, Mpa nd nd nd nd Residual Ph nd nd nd nd Kappa Number nd nd nd nd Kappa reduction, % nd nd nd nd Viscosity, dm 3 /kg nd nd nd nd Brightness, % ISO nd nd nd nd ECF Bleaching Stages used nd nd nd nd Tot. conc. Act Cl, kg/odt nd nd nd nd Tot. conc. Act. Cl mult nd nd nd nd Brightness, % ISO nd nd nd nd Viscosity, dm 3 /kg nd nd nd nd Bleached yield, % nd nd nd nd PFI beating results Brightness, % ISO nd nd nd nd SR 30 Tensile index, Nm/g nd nd nd nd Tear index, mNm 2 /g nd nd nd nd
EXAMPLES 1 and 2
[0064] Mill-scale production according to prior-art “Kamyr” continuous cooking of industrial eucalyptus chips to typical kappa numbers of eucalyptus cooking. Sampled pulps were oxygen delignified and ECF bleached in the laboratory. Bleaching chemicals demand for a given pulp brightness was determined and the pulp strength measured by beating and testing.
EXAMPLE 3
[0065] Production of eucalyptus pulp according to prior-art process disclosed in U.S. Pat. No. 3,664,918 (vapor phase pulping of water saturated lignocellulosic materials) and example 1 of U.S. Pat. No. 3,664,918.
[0066] The industrial eucalyptus chips (5.5 kg oven dry weight) were first submerged in water overnight at 2 bar overpressure and room temperature. The excess water was separated. The water saturation resulted in chips of 44.6% dry solids. The water-submerged chips were metered into a chip basked positioned in a jacketed displacement digester with liquor circulation. The chips were impregnated with white liquor (liquor (EA charge of 33.7% NaOH calculated on wood, EA 122 g NaOH/l and sulfidity 30%) at a liquor-to-wood ratio of 4 m 3 per ton of dry wood at 90° C., 60 minutes and atmospheric pressure. After impregnation of the chips and removal of excess liquor, the impregnated chips were then subjected to steaming and the temperature of the chips was initially raised to 100° C. for 20 min and subsequently treated at 175° C. for a total of 36 min, including heating-time of 7 minutes. After cooking the digester content was cooled with water. After the cook the pulp was wet disintegrated and screened. Kappa number, yield, reject, brightness were determined on the cooked pulp.
EXAMPLE 4
[0067] Production of normal eucalyptus pulp.
[0068] Example 4 show laboratory simulation data of a process simulated according to prior-art displacement batch cooking of industrial Eucalyptus.
[0069] 4.5 kg eucalyptus chips (oven dry basis) were metered into a chip basket positioned in a 26-liter jacketed displacement digester with liquor circulation. The same chip raw material as shown in Example 3 were used. The chips were pre-steamed for 10 minutes at 100° C. Then impregnation liquor fill at 80° C. was conducted with an impregnation liquor containing 0.29 mol OH − /l of EA. After 30 minutes impregnation, hot black liquor treatment occurred for 20 minutes with a HBL containing 0.205 mol OH − /l of EA and a temperature of 148° C. Then hot white liquor (105 g NaOH/l as EA, sulfidity 40%) at a charge of 11.6% as NaOH (EA) was added for 10 minutes. The digester content was then heated for 20 minutes to the cooking temperature of 160° C. The time at cooking temperature was 41 minutes. After the cook the pulp was wet disintegrated and screened. Kappa number, yield, reject, brightness were determined on the cooked pulp. The cooked pulp was then oxygen delignified and ECF bleached in the laboratory. Bleaching chemicals demand for a given pulp brightness was determined and the pulp strength measured by beating and testing.
EXAMPLE 5
[0070] Production of eucalyptus kraft pulp in accordance with an embodiment of the present invention.
[0071] 5.5 kg of oven dry eucalyptus chips was metered into a chip basket in a jacketed displacement digester with liquor circulation. The same chip raw material was used as in Example 3 and 4. The chips were first pre-steamed at 100° C. for 30 minutes. Impregnation occurred for 3 days at a temperature of 95° C. and a small overpressure of 0.5 bar. The alkalinity of the added liquor was 1.25 mol OH − /l and the liquor-to-wood ratio was 4.6 dm 3 per kg of dry wood. The added impregnation liquor contained white liquor at a sulfidity of 40% and spent liquor drained from previous impregnations using the same process. After impregnation of the chips and removal of excess liquor, pre-heated cooking liquor at various alkali concentrations (EA) was added for 5 minutes and the liquor-to-wood ratio was simultaneously adjusted to 3.5 m 3 per ton of dry wood. The digester content was heated to the cooking temperature in about 10 minutes and the temperature was kept at temperature for 10 minutes. After cooking, the digester content was cooled and the liquor was drained. After the cook the pulp was wet disintegrated and screened. Kappa number, yield, reject, brightness were determined on the cooked pulp. The cooked pulp was then oxygen delignified and ECF bleached in the laboratory. Bleaching chemicals demand for a given pulp brightness was determined and the pulp strength measured by beating and testing.
EXAMPLE 6
[0072] The experiment was carried out as disclosed in Example 5, but the impregnation time was 60 min and the cooking conditions were adjusted to give about the same kappa number as in Example 5.
EXAMPLE 7
[0073] The experiment was carried out as disclosed in Example 6, but the cooking conditions were adjusted to give a higher cooking kappa number.
EXAMPLE 8
[0074] The experiment was carried out as disclosed in Example 7, but the impregnation time was adjusted to 180 minutes and the cooking conditions were adjusted to give slightly higher kappa number than in Example 7.
EXAMPLE 9
[0075] The experiment was carried out as disclosed in Example 8, but the impregnation time was adjusted to 3 days and the cooking conditions were adjusted to give slightly higher kappa number compared to Example 8.
EXAMPLE 10
[0076] The experiment was carried out as disclosed in Example 6, but the impregnation pressure was adjusted to 10 bar and the cooking conditions were adjusted to give slightly higher kappa number compared to Example 6.
EXAMPLE 11
[0077] The experiment was carried out as disclosed in Example 8, but the impregnation pressure was adjusted to 10 bar and the cooking conditions were adjusted to give slightly lower kappa number compared to Example 8.
[0078] Table 1 shows the cooking characteristics of Eucalyptus hardwood chips, unbleached pulp results and the subsequent oxygen delignification, ECF bleaching and PFI beating results. All oxygen delignifications, ECF bleachings, PFI beatings and tests were performed in the laboratory.
[0079] The effect of impregnation time is shown in FIG. 11. The reject percentage is shown as a function of impregnation time as pulp is cooked according to the invention to kappa numbers 20 and 25 using a total heat-up and cooking time of 25 min. It is seen, that a satisfactory level is reached when 1 hour impregnation residence time is used; a further half per cent decrease is achieved by extending impregnation with a further hour. The improvement due to extension to even three days is marginal. However, table 1 shows that the bleaching chemical consumption is significantly lower and bleached pulp viscosity is higher when using 3 days impregnation.
[0080] Based on the results in Table 1 and FIGS. 8 to 11 , the present invention offers the following surprising benefits over a state-of-the-art cooking process:
[0081] remarkably shorter residence time in heating and cooking can be used compared to over 1.5 hours in prior-art Kamyr-type continuous digesters and in prior-art displacement batch digesters
[0082] the required cooking volume is considerable reduced
[0083] the unbleached and oxygen bleached pulp is brighter pulp at same kappa number
[0084] lower or equal rejects amounts at same or higher kappa number. In a process according to the invention and according to the methods described, the reject level depends on the impregnation time and kappa number target (see FIG. 10 showing reject levels of pulps at kappa numbers 20 and 25 and impregnation times of 0-3 days using a retention time of 25 minutes in heating and cooking)
[0085] the reject level is independent on impregnation pressure in the range 0.5 bar to 10 bar for pre-steamed chips implementing that low-pressure impregnation equipment can be used in impregnation
[0086] higher unbleached screened yield
[0087] higher kappa number reduction in oxygen delignification. Example 7 used more NaOH in oxygen delignification, but the additional cost for this is minor since oxidized white liquor from the recovery cycle, i.e. low-cost NaOH, is usually used in oxygen delignification.
[0088] considerable lower active chlorine chemical consumption in ECF bleaching by about 50-65%
[0089] bleached pulps gives a pulp of higher viscosity, see example 5,
[0090] higher bleached yield at lower bleaching costs.
[0091] higher tensile strength although the brightness of the pulps are higher
[0092] The following examples make clear some advantages of the present invention over prior art kraft batch cooking when cooking industrial softwood chips.
EXAMPLES 12 AND 13
[0093] Production of a normal “reference” softwood kraft pulp by using prior-art displacement kraft batch technology.
[0094] 4.2 kg Scandinavian softwood chips (oven dry basis) were metered into a chip basket positioned in a 26-liter jacketed displacement digester with liquor circulation. Industrial chips were used consisting of 10% over-thick chips (fraction retained on a 8 mm wide bar) and 90% of so-called accept chips (chip fractions retained between 8 mm wide bars and 13 mm holes). The lid of the digester was closed. The impregnation liquor (IL) was pumped into the digester. The amount of the IL was 4.5 l/kg o.d. wood and EA 0.3 mol/l. The conditions in the impregnation step were total time 20 min, temperature 90° C. and pressure 3 bar. After the impregnation stage followed immediately the hot black liquor stage and hot white liquor stage. The hot black liquor and hot white liquor displaced the IL. The amount of hot black liquor was 4.0 l per kg o.d. wood and EA 0.45 mol/l. The conditions in the hot black liquor and hot white liquor stage were: Total time 30 min, temperature 5° C. below cooking temperature and pressure 7.0 bar. Then temperature adjustment and cooking by circulation followed. The hot white liquor was also split charged, so that 70% was charged at the hot black liquor fill and 30% after 15 min at cooking temperature. The cooking time was varied by having different cooking temperatures. At the target H-factor, displacement liquor was pumped into the digester cooling the pulp. The conditions in the final displacement were: Temperature 80° C., time 50 min and total amount of liquor 7.0 l/kg o.d wood. After the cook, the pulp was wet disintegrated and screened. Kappa number, yield, reject, brightness and viscosity were analyzed on the pulp.
[0095] Cooking characteristics are shown in table 2.
TABLE 2 Results of Example 12 and 13 EXAMPLE 12 EXAMPLE 13 Impregnation liquor, min 20 20 Impregnation liquor, EA mol OH − /l 0.3 0.3 Hot black liquor + hot white liquor 30 30 addition time, min Hot black Liquor, EA mol OH − /l 0.45 0.45 Hot White Liquor Charge, EA % 16.9 16.6 NaOH Temperature adjustment + cooking 80 60 time, min Cooking temperature 169 172 H-factor 1050 1000 Total heating and cooking time, min 110 90 End of cook residual, EA mol OH − /l 0.45 0.5 Kappa Number 31.5 31.1 Total Yield, % on wood 47.7 47.6 Coarse reject, % on wood 1.03 1.98 Fine reject, % on wood 0.42 0.66 Screened yield, % on wood 46.3 45.0 Viscosity, dm 3 /kg 1154 1094 Brightness, % ISO 32 30
EXAMPLE 14
[0096] Production of softwood kraft pulp by using displacement kraft batch technology according to an embodiment of the invention.
[0097] 4.2 kg Scandinavian softwood chips (oven dry basis) were metered into a chip basket positioned in a 26-liter jacketed displacement digester with liquor circulation. The same chips as in examples 12 and 13 were used. The lid of the digester was closed. The chips were steamed for 20 min at 100° C. Impregnation liquor (IL) was pumped into the digester and circulation put on for 20 minutes. After 20 minutes of circulation was the circulation stopped and the chips were impregnated for a total time of 180 minutes. The temperature of the impregnation stage was 95° C. and the effective alkali concentration of added impregnation liquors was 1.3 mol OH − /l. The overpressure was 0.3 bar in the top of the digester. After the impregnation stage, a hot black liquor and hot white liquor fill stage followed immediately. The hot black liquor and hot white liquor displaced the spent impregnation liquor. The amount of hot black liquor was 4.2 l/kg o.d. wood and EA 0.45 mol OH − /l. The conditions in the hot black liquor and hot white liquor fill stage were: Total time 30 min, temperature 5° C. below maximum cooking temperature and pressure 7.0 bar. Then lo temperature adjustment and cooking by circulation followed. The total heating and cooking time was 70 min. At the target H-factor displacement liquor was pumped into the digester, cooling the pulp. The conditions in the final displacement were: Temperature 80° C., time 50 min and total amount of liquor 6.7 l/kg o.d. wood. After the cook, the pulp was wet disintegrated and screened. Kappa number, yield, reject, brightness and viscosity were determined on the pulp.
TABLE 3 Results of Example 14 EXAMPLE 14 Impregnation liquor, min 180 Impregnation liquor, BA mol OH − /l 1.3 Hot black liquor + hot white 30 liquor addition time, min Hot black Liquor, EA mol OH − /l 0.45 Hot White Liquor Charge, EA % NaOH 6.4 Temperature adjustment + 40 cooking time, min Cooking temperature 174 H-factor 808 Total heating and cooking time, min 70 End of cook residual, EA mol/l 0.45 Kappa Number 30.6 Total Yield, % on wood 48.1 Coarse reject, % on wood 0.76 Fine reject, % on wood 0.22 Screened yield, % on wood 47.1 Viscosity, dm 3 /kg 1138 Brightness, % ISO 33
[0098] Based on the results shown in tables 2 and 3, the present invention offers the following surprising benefits over a state-of-the-art cooking process:
[0099] By using over 60 minutes pre-impregnation in a vessel outside of the displacement kraft batch digester according to method presented in example 14,
[0100] the heat-up and cooking time can be reduced by over 50% compared to a prior art process at the same kappa number and reject level (sum of coarse and fine reject). Decrease of total cycle time by at least 40 min, which for a reference installation with total cycle time of 220 min means a production increase of at least 18%. A lower number of batch digesters or lower total batch digester volume can be used to reach a given production level.
[0101] lower reject level although 40 min shorter heating and cooking time
[0102] the screened yield is significantly higher.
[0103] the unbleached brightness is slightly higher.
[0104] The following examples make clear some advantage of the present invention over prior art kraft batch cooking in terms of the equipment required.
EXAMPLE 15
[0105] Production of 1800 air dry tons softwood kraft pulp per day by using prior-art displacement kraft batch technology
[0106] The total batch digester volume required is about 4000 m 3 using 10 times 400 m 3 digesters.
EXAMPLES 16-18
[0107] Production of 1800 air dry tons softwood kraft pulp per day by using a displacement kraft batch cooking process according to the invention.
[0108] Examples 16 to 18 show that the same production can be made with a total batch digester volume of 2400 to 2800 m 3 using a lower number of digesters. The examples show, that the volume ratios between the individual batch digesters and the impregnation vessel are about 2 to 6.8.
TABLE 4 Results of Example 15-18 EXAMPLE EXAMPLE EXAMPLE EXAMPLE 15 16 17 18 Production, 1800 1800 1800 1800 adt/d Digester size, 400 350 350 300 m 3 Number of 10 8 8 8 batch digesters Total volume 4000 2800 2800 2400 of batch digesters, m 3 Impregnation 60 120 180 retention time, min Impregnation 700 1370 2050 vessel, m 3 Ratio between 2 3, 9 6, 8 impregnation vessel and batch digester volume
[0109] Based on the results shown in table 4, the present invention offers the following surprising benefits over a state-of-the-art cooking process:
[0110] A lower number of batch digesters can be used which also means less pressure vessels, piping, instruments etc.
[0111] A lower total batch digester volume can be used to reach a given production level.
[0112] In order to lower the batch digester volume and the number of batch digesters, an impregnation vessel is used which according to the invention can be designed for much lower pressure and temperature conditions. In addition, the building requirements are much lower with a method according to the invention as the digester is preferably filled with chips hydraulically from the bottom. The chip silo and capping valve above the batch digesters can also be eliminated. The ratio between the impregnation vessel digester volume is important in order to obtain sufficient pre-impregnation.
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An alkaline batch process for the production of pulp from wood chips, wherein the preheated chips are subjected to an extended impregnation step outside the digester for at least 60 min, preferably longer, at a temperature not exceeding the impregnation liquor boiling point at atmos-pheric conditions, and a rapid heating and cooking period in the digester of less than about 90 min, preferably shorter, followed by cooling to below reaction tempera-ture. Fresh alkali is added both during impregnation and the heating/cooking period.
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TECHNICAL FIELD OF THE INVENTION
Embodiments of the present invention relate to podophyllotoxin-type derivatives, mainly related to aniline-substituted podophyllotoxin-type derivatives after substituting position 4 of the C-ring of 4′-demethylepipodophyllotoxin or podophyllotoxin, and preparation method thereof. Embodiments of the present the invention also relate to use of aniline-substituted podophyllotoxin-type derivatives in the preparation of anti-tumor drugs, belonging to field of preparation and application of podophyllotoxin-type derivatives.
BACKGROUND OF THE INVENTION
Podophyllotoxin and 4′-demethylepipodophyllotoxin are precursor compounds with unique anti-tumor natural activity, extracted from podophylloideae plants (such as Berberidaceae Sinopodophyllum hexandrum, umbrellaleaf, dysosma versipellis etc.). However, podophyllotoxin or 4′-demethylepipodophyllotoxin has more or less shortcomings to be overcome, such as strong toxic and side effect and poor bioavailability, thus limiting their clinical application.
SUMMARY OF THE INVENTION
One purpose of embodiments of the present invention is to provide a kind of aniline-substituted podophyllotoxin-type derivatives with anti-tumor activity;
Second purpose is to provide a method for preparing or purifying the aniline-substituted podophyllotoxin derivatives;
Third purpose is to apply the aniline-substituted podophyllotoxin derivatives and salts thereof to the preparations of the clinical anti-tumor drugs.
The purposes as above are realized by the following technical scheme:
Structural formula of aniline-substituted podophyllotoxin-type derivatives with anti-tumor activity are illustrated on formula (V):
wherein R1 is hydrogen or methyl;
R2 is selected from
In addition, of course, acid salts of compounds of formula (V) are also included in the scope of embodiments of the present invention. Preferably, the acid salts include hydrochloride, phosphate, and so on.
Anilines are a pharmaceutical intermediates of antineoplastic drugs in which benzene ring is capable of generating π-π bond with biological macromolecules, and these compounds with benzene ring contain active atoms such as chlorine, nitrogen, sulfur, which can enhance binding capacity of the compounds with tubulin or topoisomerase II, making it act on active sites of tubulin and topoisomerase II better, so that the drug's anti-tumor activity increased. With embodiment of the present invention, based on the principle of drug combination, taking these compounds as derivatives of nucleus, taking 4′-demethylepipodophyllotoxin and 4-chloro-3-methylaniline, 3-fluoro-4-methoxyaniline, 4,4′-diaminodiphenylmethane, o-anisidine, 4-chloro-2-aminoanisole, o-aminobenzonitrile, 2,6-dichloro-4-aminophenol, N,N-dimethylamino metanil, 2-ethyl-5-nitroaniline, 2 2′-diaminodiphenylsulfide, or 2-aminobenzotrifluoride as functional groups modified from structure of podophyllotoxin or 4′-demethylepipodophyllotoxin, which are introduced into position 4 of C-ring of podophyllotoxin and 4′-demethylepipodophyllotoxin, to get the compound as shown in formula (V) in embodiment of the present invention.
The second purpose is to provide a method for preparing the above compound of above formula (V), which is comprising the steps of: by aniline reaction, 4-chloro-3-methylaniline, 3-fluoro-4-methoxyaniline, 4,4′-diaminodiphenylmethane, o-anisidine, 4-chloro-2-aminoanisole, o-aminobenzonitrile, 2,6-dichloro-4-aminophenol, N,N-dimethylamino metanil, 2-ethyl-5-nitroaniline, 2 2′-diaminodiphenylsulfide or 2-aminobenzotrifluoride is introduced into position 4 of C-ring of podophyllotoxin and 4′-demethylepipodophyllotoxin, to get the compound as shown in formula (V).
The aniline reaction is preferably carried out under conditions as below: (1) position 4 of C-ring of podophyllotoxin or 4′-demethylepipodophyllotoxin is activated; (2) podophyllotoxin or 4′-demethylepipodophyllotoxin with activated position 4 of C-ring is dissolved in organic solvent, then added 4-chloro-3-methylaniline, 3-fluoro-4-methoxyaniline, 4,4′-diaminodiphenylmethane, o-aminoanisole, 4-chloro-2-aminoanisole, o-aminobenzonitrile, 2,6-dichloro-4-aminophenol, N,N-dimethylamino metanil, 2-ethyl-5-nitroaniline, 2 2′-diaminodiphenylsulfide or 2-aminobenzotrifluoride, stirred to carried out aniline reaction.
Wherein manner of activation of position 4 of C-ring of podophyllotoxin and 4′-demethylepipodophyllotoxin is to use hydrobromic acid to activate position 4 of C-ring of podophyllotoxin and 4′-demethylepipodophyllotoxin; more preferably, the manner of activation include the steps of: podophyllotoxin and 4′-demethylepipodophyllotoxin being dried, and under protection of nitrogen, hydrobromic acid being added while stirring under ice-bath; after the addition, ice-bath is removed, then reacting under 20-25° C. for 5-12 hours.
The organic solvent in step (2) is preferably methylene chloride.
To achieve better synthesis effect, in aniline reaction, molar ratio between podophyllotoxin or 4′-demethylepipodophyllotoxin and 4-chloro-3-methylaniline, 3-fluoro-4-methoxyaniline, 4,4′-diaminodiphenylmethane, o-aminoanisole, 4-chloro-2-aminoanisole, o-aminobenzonitrile, 2,6-dichloro-4-aminophenol, N,N-dimethylamino metanil, 2-ethyl-5-nitroaniline, 2 2′-diaminodiphenylsulfide or 2-aminobenzotrifluoride is preferably 1:2.
Stirring in step (2) is preferably such a stirring in vacuo with preferred rotational speed of 50 to 800 rpm, more preferred 600 rpm. Temperature of the aniline reaction is preferably 80° C., reaction time is preferably 12-48 hours, more preferably 48 hours.
In order to achieve better technical effect, above reaction product can be subjected to preliminary purification under the following conditions to get preliminarily purified anilino podophyllotoxin-type derivative as product: anilino podophyllotoxin-type as crude product is subjected rotary evaporation and concentration, then extracted by methylene chloride and water with volume ratio of 1:1 three times, then organic layer is collected, and dried in vacuo to get the preliminarily purified anilino podophyllotoxin-type derivative as product.
The embodiment of present invention also provides a method of further purification of the preliminarily purified aniline-substituted podophyllotoxin-type derivative as product, comprising:
(1) preparation of sample to be separated and purified: preliminarily purified anilino-substituted podophyllotoxin-type derivative as product being extracted by methylene chloride and water with volume ratio of 1:1 three times, and dried in vacuo after organic layer is collected, to be use later;
(2) separation and purification: sample prepared in step (1) being subjected to silica gel column chromatography and gel column chromatography separations sequentially, to obtain product;
Preferably, separation method by silica gel column chromatography comprises: (1) the silica gel column chromatography being normal phase silica gel column chromatography, wherein normal phase silica gel is mixed in organic solvent with low polarity, loaded into column, balanced with eluent which is preferably formed from chloroform and acetone with volume ratio of 10:1; (2) samples being dissolved with the eluent, subjected to sample adsorption, then eluted with eluent which is collected later, then the sample being evaporated to dryness and recrystallized;
Preferably, separation method by gel column chromatography comprises: (1) soaking the gel in methanol; loading processed gel into column and balanced with methanol; (2) sample preliminary separated by silica gel column chromatography being dissolved in methanol, subjected to sample absorption, and then eluated with eluent which is collected later, then the sample being evaporated to dryness and recrystallized;
According to embodiments of the present invention, podophyllotoxin or 4′-demethylepipodophyllotoxin and 4-chloro-3-methylaniline, 3-fluoro-4-methoxyaniline, 4,4′-diaminodiphenylmethane, o-aminoanisole, 4-chloro-2-aminoanisole, o-aminobenzonitrile, 2,6-dichloro-4-aminophenol, N,N-dimethylamino metanil, 2-ethyl-5-nitroaniline, 2 2′-diaminodiphenylsulfide or 2-aminobenzotrifluoride are subjected to aniline reaction, to get the compound of formula (V) with good anti-tumor activity, which can act on tumor cells by multi-path, multi-target point, thereby achieving better anti-tumor efficacy. In vitro BGC823, Hela, A549 cells activity inhibition tests show that the compound of formula (V) of embodiment of the invention has significantly better antitumor activity than podophyllotoxin or 4′-demethylepipodophyllotoxin. Result of the test indicates that the compound of formula (V) can be used to prepare anticancer drugs, which can be clinically applied to anti-tumor therapy.
Another object of embodiment of the present invention is to provide a kind of pharmaceutical composition, which is formed from combination of the compound of the formula (V) and a pharmaceutically acceptable carrier, that is, after combining of compound of the formula (V) with pharmaceutically acceptable amount and the pharmaceutically acceptable carrier, according to conventional preparing methods in the art, it can be used to preparing any kind of suitable pharmaceutical composition, e.g., which may be in the form of tablets, capsules, powders, granules, pastilles, suppositories, or a liquid form of oral or sterile parenteral suspensions and the like, may also be form of large or small volume of injection, freeze-dried powder, sterile powder dispensing and the like. Typically, the pharmaceutical composition is suitable for oral administration and injection administration, is also suitable for other methods of administration, such as transdermal administration.
In order to achieve consistency of administration, the pharmaceutical composition of embodiment of the present invention is preferably in a form of single agent. Form of single agent for oral administration may be tablets and capsules, and may contain conventional excipients such as binders, e.g., syrup, acacia, gelatin, sorbitol, tragacanth, or polyvinylpyrrolidone; fillers, e.g., lactose, sugar, maize-starch, calcium phosphate, sorbitol or glycine; tabletting lubricants, e.g., magnesium stearate; disintegrants, e.g., starch, polyvinylpyrrolidone, sodium starch glycollate or microcrystalline cellulose, or a pharmaceutically acceptable wetting agents, such as sodium lauryl sulfate.
DESCRIPTION OF THE FIGURES
FIG. 1 shows result of general formula of aniline-substituted podophyllotoxin-type derivatives according to embodiment of the invention;
FIG. 2 shows structural formula of podophyllotoxin and 4′-demethylepipodophyllotoxin;
FIG. 3 shows structural formula of 4-chloro-3-methylaniline, 3-fluoro-4-methoxyaniline, 4,4′-diaminodiphenylmethane, o-aminoanisole, 4-chloro-2-aminoanisole, o-aminobenzonitrile, 2,6-dichloro-4-aminophenol, N,N-dimethylamino metanil, 2-ethyl-5-nitroaniline, 2 2′-diaminodiphenylsulfide or 2-aminobenzotrifluoride;
FIG. 4 shows chemical structural formula of 22 aniline podophyllotoxin-type derivatives.
DETAILED DESCRIPTION OF THE INVENTION
For a fuller understanding of the nature and advantages of the present invention, reference should be made to the ensuing detailed description and the accompanying drawings. Other aspects, objects and advantages of the invention will be apparent from the drawings and the detailed description that follows. it should be noted that, the above embodiments are used to explain the technical solution of the present invention and the present invention should not be construed as being limited to such embodiments, although the present invention has been described in detail with reference to preferred embodiments thereof, it will be understood by those of ordinary skill in the art that various changes or equative replacements may be made to the technical solution of the present invention without departing from the spirit and scope of the present invention as defined by the following claims.
Test Material
podophyllotoxin and 4′-demethylepipodophyllotoxin: bought from Xi'an Helin Bio-technique Co., Ltd, with purity of 98%; 4-chloro-3-methylaniline, 3-fluoro-4-methoxyaniline, 4,4′-diaminodiphenylmethane, o-aminoanisole, 4-chloro-2-aminoanisole, o-aminobenzonitrile, 2,6-dichloro-4-aminophenol, N,N-dimethylamino metanil, 2-ethyl-5-nitroaniline, 2 2′-diaminodiphenylsulfide or 2-aminobenzotrifluoride, bought from Aladdin reagents.
Preparatory Test Example 1: Activation of Position 4 of C-Ring of Podophyllotoxin and 4′-Demethylepipodophyllotoxin
Drying of dichloromethane: taking 1.5 g of calcium hydride to 1000 ML 4-neck flask with round bottom; putting clean funnel into side open thereof; pouring 500 ML of dichloromethane; adding 3-4 glass beads to prevent bumping, heated to the temperature of slightly boiling state of dichloromethane, added to reflux pipe to reflow for 2-3 h, then condensed and collected to reagent bottle containing anhydrous calcium chloride; after that, inputting a little nitrogen to the bottle, closing lid thereof; after each use, nitrogen will be supplemented.
Taking 2 g of podophyllotoxin or 4′-demethylepipodophyllotoxin, which is dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried podophyllotoxin or 4′-demethylepipodophyllotoxin and 40 ml of dried dichloromethane were added into 250 ml 4-necked flask, cooled with ice-bath to 0° C., stirred and slowly dropwise added with 5.4 ml of hydrobromic acid; after the addition, ice-bath is removed, then reacting under 25° C. for 5-12 hours. After completion of the reaction, reaction solution is extracted with 20 ml of water, and the lower layer organic phase was taken and repeatedly extracted with saturated aqueous sodium chloride solution three times; and the organic phase is taken and dried in anhydrous sodium sulfate for a night; taking supernatant to be dried by rotary evaporation, then adding 20 ml of ethyl acetate to be dissolved; after that, n-hexane is slowly added dropwise to the solution which then is shaken until no crystals were precipitated, overnighted at 4° C., then crystals are separated from the liquid, resulting compound is activated product of position 4 of C-ring of podophyllotoxin or 4′-demethylepipodophyllotoxin.
Embodiment 1: synthesis and purification of 4-N-(4-chloro-3-methylaniline)-4-deoxy-podophyllotoxin (Compound (1))
(1) Synthesis of 4-N-(4-chloro-3-methylaniline)-4-deoxy-podophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of podophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of podophyllotoxin and 2 mol of 4-chloro-3-methylaniline, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(4-chloro-3-methylaniline)-4-deoxy-podophyllotoxin.
(2) Separation and purification of 4-N-(4-chloro-3-methylaniline)-4-deoxy-podophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=10:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=5:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(4-chloro-3-methylaniline)-4-deoxy-podophyllotoxin.
4-N-(4-chloro-3-methylaniline)-4-deoxy-podophyllotoxin: white powder: C 29 H 28 ClNO 7 ; 537, 1 H NMR (300 MHz, CDCl 3 ): δ 2.297 (s, 3H, —CH 3 ), 2.977 (m, 1H, 2-H), 3.089 (d, J=13.5 Hz, 1H, 3-H), 3.737 (s, 6H, 3′, 5′-OCH 3 ), 3.794 (s, 3H, 4′-OCH 3 ), 3.956 (t, J=9.3 Hz, 1H, 11-H), 4.359 (t, J=7.9 Hz, 1H, 11-H), 4.574 (d, J=12.6 Hz, 2H, 4-H, 1-H), 5.949 (t, J=2.5 Hz, 2H, OCH 2 O), 6.303 (s, 3H, ArH), 6.412 (s, 1H, ArH), 6.510 (s, 1H, ArH), 6.731 (d, J=1.5 Hz, 1H, ArH), 7.122 (t, J=8.7 Hz, 1H, ArH) 13 C NMR (75 MHz, CDCl 3 ): δ 20.512, 38.814, 41.937, 43.696, 52.826, 56.399, 60.901, 68.975, 101.711, 108.393, 109.237, 110.053, 110.996, 114.864, 123.558, 129.959, 130.550, 131.872, 135.206, 137.176, 146.165, 147.783, 148.430, 152.748, 174.849
Embodiment 2: synthesis and purification of 4-N-(4-chloro-3-methylaniline)-4-deoxy-4′-demethylepipodophyllotoxin (Compound (2))
(1) Synthesis of 4-N-(4-chloro-3-methylaniline)-4-deoxy-4 ‘-demethylepipodophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of 4’-demethylepipodophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin and 2 mol of 4-chloro-3-methylaniline, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(4-chloro-3-methylaniline)-4-deoxy-4′-demethylepipodophyllotoxin.
(2) Separation and purification of 4-N-(4-chloro-3-methylaniline)-4-deoxy-4′-demethylepipodophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=10:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=10:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(4-chloro-3-methylaniline)-4-deoxy-4′-demethylepipodophyllotoxin.
4-N-(4-chloro-3-methylaniline)-4-deoxy-4′-demethylepipodophyllotoxin: white powder: C 28 H 26 ClNO 7 ; 523, 1 H NMR (300 MHz, CDCl 3 ): δ 2.303 (s, 3H, —CH 3 ), 2.965-3.012 (m, 1H, 2-H), 3.071 (dd, J=4.8 Hz, 1H, 3-H), 3.775 (s, 6H, 3′, 5′-OCH 3 ), 3.950 (t, J=9.3 Hz, 1H, 11-H), 4.349 (t, J=7.8 Hz, 1H, 11-H), 4.556 (dd, J=4.8 Hz, 2H, 4-H, 1-H), 5.937 (d, J=6.6 Hz 2H, OCH 2 O), 6.316 (s, 3H, ArH), 6.421 (s, 1H, ArH), 6.508 (s, 1H, ArH), 6.740 (s, 1H, ArH), 7.126 (d, J=8.1 Hz, 1H, ArH) 13 C NMR (75 MHz, CDCl 3 ): δ 20.614, 38.855, 42.090, 43.604, 52.836, 56.695, 69.103, 101.785, 108.152, 109.369, 110.126, 111.076, 114.935, 123.484, 130.029, 130.682, 130.816, 132.122, 134.289, 137.243, 146.356, 146.682, 147.781, 148.463, 175.120
Embodiment 3: synthesis and purification of 4-N-(3-fluoro-4-methoxyaniline)-4-deoxy-podophyllotoxin (Compound (3))
(1) Synthesis of 4-N-(3-fluoro-4-methoxyaniline)-4-deoxy-podophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of podophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of podophyllotoxinand and 2 mol of 3-fluoro-4-methoxyaniline, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(3-fluoro-4-methoxyaniline)-4-deoxy-podophyllotoxin.
(2) Separation and purification of 4-N-(3-fluoro-4-methoxyaniline)-4-deoxy-podophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=10:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=5:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(3-fluoro-4-methoxyaniline)-4-deoxy-podophyllotoxin.
4-N-(3-fluoro-4-methoxyaniline)-4-deoxy-podophyllotoxin: white powder: C 29 H 28 FNO 8 ; 537, 1 H NMR (300 MHz, CDCl 3 ): 2.997-3.009 (m, 1H, 2-H), 3.110 (dd, J=4.8 Hz, 1H, 3-H), 3.757 (s, 6H, 3′, 5′-OCH 3 ), 3.808 (d, J=8.1 Hz, 6H, 4′-OCH 3 , Ar—OCH 3 ) 3.995 (t, J=9.9 Hz, 1H, 11-H), 4.386 (t, J=7.5 Hz, 1H, 11-H), 4.579 (t, J=5.1 Hz, 2H, 4-H, 1-H), 5.952 (d, J=5.1 Hz 2H, OCH 2 O), 6.235 (d, J=9.0 Hz, 1H, ArH), 6.315 (s, 2H, ArH), 6.380 (s, 1H, ArH), 6.520 (s, 1H, ArH), 6.755 (s, 1H, ArH), 6.853 (t, J=9.0 Hz, 1H, ArH) 13 C NMR (75 MHz, CDCl 3 ): δ 38.890, 42.013, 43.814, 53.436, 56.503, 57.713, 61.005, 69.051, 101.576, 101.801, 107.456, 108.497, 109.285, 110.185, 116.375, 130.696, 131.962, 135.338, 142.738, 147.887, 148.534, 153.867, 175.009
Embodiment 4: synthesis and purification of 4-N-(3-fluoro-4-methoxyaniline)-4-deoxy-4′-demethylepipodophyllotoxin (Compound (4))
(1) Synthesis of 4-N-(3-fluoro-4-methoxyaniline)-4-deoxy-4′-demethylepipodophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin and 2 mol of 3-fluoro-4-methoxyaniline, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 48 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(3-fluoro-4-methoxyaniline)-4-deoxy-4′-demethylepipodophyllotoxin.
(2) Separation and purification of 4-N-(3-fluoro-4-methoxyaniline)-4-deoxy-4′-demethylepipodophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=20:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=10:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(3-fluoro-4-methoxyaniline)-4-deoxy-4′-demethylepipodophyllotoxin.
4-N-(3-fluoro-4-methoxyaniline)-4-deoxy-4′-demethylepipodophyllotoxin: white powder: C 28 H 26 FNO 8 ; 523, 1 H NMR (300 MHz, CDCl 3 ): 2.953-2.987 (m, 1H, 2-H), 3.079 (dd, J=4.8 Hz, 1H, 3-H), 3.773 (s, 6H, 3′, 5′-OCH 3 ), 3.826 (s, 3H, Ar—OCH 3 ) 3.971 (t, J=7.8 Hz, 1H, 11-H), 4.354 (t, J=7.5 Hz, 1H, 11-H), 4.552 (s, 2H, 4-H, 1-H), 5.932 (d, J=7.8 Hz 2H, OCH 2 O), 6.226 (d, J=9.0 Hz, 1H, ArH), 6.314 (s, 2H, ArH), 6.367 (s, 1H, ArH), 6.502 (s, 1H, ArH), 6.744 (s, 1H, ArH), 6.853 (t, J=9.0 Hz, 1H, ArH) 13 C NMR (75 MHz, CDCl 3 ): δ 38.810, 42.090, 43.619, 53.400, 56.695, 57.704, 69.073, 101.533, 107.425, 108.137, 109.280, 110.156, 116.286, 130.712, 130.816, 132.107, 134.289, 142.779, 146.682, 147.810, 148.478, 175.105
Embodiment 5: synthesis and purification of 4-N-(4,4′-diaminodiphenylmethane)-4-deoxy-podophyllotoxin (Compound (5))
(1) Synthesis of 4-N-(4,4′-diaminodiphenylmethane)-4-deoxy-podophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of podophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of podophyllotoxinand and 2 mol of 4,4′-diaminodiphenylmethane, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 48 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(4,4′-diaminodiphenylmethane)-4-deoxy-podophyllotoxin.
(2) Separation and purification of 4-N-(4,4′-diaminodiphenylmethane)-4-deoxy-podophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=15:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=10:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(4,4′-diaminodiphenylmethane)-4-deoxy-podophyllotoxin.
4-N-(4,4′-diaminodiphenylmethane)-4-deoxy-podophyllotoxin: white powder: C 35 H 34 N 2 O 7 ; 594, 1 H NMR (300 MHz, CDCl 3 ): δ 3.266-3.331 (m, 2H, 2-H, 3-H), 3.651 (s, 6H, 3′, 5′-OCH 3 ), 3.708 (s, 3H, 4′-OCH 3 ), 3.935 (t, J=9.3 Hz, 1H, 11-H), 4.411 (t, J=7.8 Hz, 1H, 11-H), 4.618 (d, J=1.8 Hz, 2H, 1-H, 4-H), 5.928 (s, 2H, OCH 2 O), 6.268 (s, 4H, ArH), 6.414-6.497 (m, 6H, ArH), 6.556 (d, J=8.1 Hz, 4H, ArH), 6.714 (s, 2H, ArH), 6.806 (d, J=7.8 Hz, 2H, ArH), 6.868 (d, J=8.1 Hz, 2H, ArH) 13 C NMR (75 MHz, CDCl 3 ): δ 39.192, 41.414, 43.665, 51.206, 56.523, 60.631, 69.295, 101.821, 108.911, 109.811, 112.484, 114.763, 129.675, 129.815, 130.687, 132.432, 136.652, 147.147, 147.737, 152.661, 175.535
Embodiment 6: synthesis and purification of 4-N-(4,4′-diaminodiphenylmethane)-4-deoxy-4′-demethylepipodophyllotoxin (Compound (6))
(1) Synthesis of 4-N-(4,4′-diaminodiphenylmethane)-4-deoxy-4′-demethylepipodophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin and 2 mol of 4,4′-diaminodiphenylmethane, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(4,4′-diaminodiphenylmethane)-4-deoxy-4′-demethylepipodophyllotoxin.
(2) Separation and purification of 4-N-(4,4′-diaminodiphenylmethane)-4-deoxy-4′-demethylepipodophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=10:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=5:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(4,4′-diaminodiphenylmethane)-4-deoxy-4′-demethylepipodophyllotoxin.
4-N-(4,4′-diaminodiphenylmethane)-4-deoxy-4′-demethylepipodophyllotoxin: white powder: C 34 H 32 N 2 O 7 ; 580, 1 H NMR (300 MHz, CDCl 3 ): δ 2.988 (m, 1H, 2-H), 3.116 (dd, J=4.8 Hz, 1H, 3-H), 3.784 (s, 6H, 3′, 5′-OCH 3 ), 4.000 (t, J=7.1 Hz, 1H, 11-H), 4.352 (t, J=7.8 Hz, 1H, 11-H), 4.591-4.624 (m, 2H, 1-H, 4-H), 5.943 (d, J=4.2 Hz, 2H, OCH 2 O), 6.326 (s, 2H, ArH), 6.444-6.511 (m, 3H, ArH), 6.617 (d, J=8.1 Hz, 2H, ArH), 6.755 (s, 1H, ArH), 6.960-7.021 (m, 3H, ArH), 7.021 (s, 2H, ArH), 7.528 (d, J=3.6 Hz, 1H, ArH), 7.688 (d, J=5.4 Hz, 1H, ArH) 13 C NMR (75 MHz, CDCl 3 ): δ 39.192, 41.414, 43.665, 51.281, 56.692, 69.244, 101.739, 109.214, 109.772, 112.477, 114.765, 129.631, 129.799, 130.133, 130.663, 131.054, 132.281, 135.377, 147.092, 147.706, 147.817, 175.571
Embodiment 7: synthesis and purification of 4-N-(o-aminoanisole)-4-deoxy-podophyllotoxin (Compound (7))
(1) Synthesis of 4-N-(o-aminoanisole)-4-deoxy-podophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of podophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of podophyllotoxinand and 2 mol of o-aminoanisole, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(o-aminoanisole)-4-deoxy-podophyllotoxin.
(2) Separation and purification of 4-N-(o-aminoanisole)-4-deoxy-podophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=10:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=5:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(o-aminoanisole)-4-deoxy-podophyllotoxin.
4-N-(o-aminoanisole)-4-deoxy-podophyllotoxin: white powder: C 29 H 29 NO 8 ; 519, 1 H NMR (300 MHz, CDCl 3 ): δ 2.943-2.977 (m, 1H, 2-H), 3.142 (dd, J=4.8 Hz, 1H, 3-H), 3.700 (s, 6H, 3′, 5′-OCH 3 ), 3.700 (s, 6H, Ar—OCH 3 , 4′-OCH 3 ), 3.911 (t, J=9.9 Hz, 1H, 11-H), 4.321 (t, J=7.8 Hz, 1H, 11-H), 4.551 (d, J=4.5 Hz, 1H, 4-H), 4.606 (d, J=3.6 Hz, 1H, 1-H), 5.898 (s, 2H, OCH 2 O), 6.273 (s, 2H, ArH), 6.421-6.469 (m, 2H, ArH), 6.663-6.760 (m, 3H, ArH), 6.825 (t, J=7.5 Hz, 1H, ArH) 13 C NMR (75 MHz, CDCl 3 ): δ39.156, 42.140, 43.911, 52.488, 55.640, 56.547, 60.996, 69.252, 101.719, 108.665, 109.167, 109.627, 110.045, 117.841, 121.412, 131.118, 132.067, 135.525, 137.561, 146.571, 147.812, 148.426, 152.861, 175.105
Embodiment 8: synthesis and purification of 4-N-(o-aminoanisole)-4-deoxy-4′-demethylepipodophyllotoxin (Compound (8))
(1) Synthesis of 4-N-(o-aminoanisole)-4-deoxy-4′-demethylepipodophyllotoxin (Compound (8)): taking 1 mol of activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin and 2 mol of o-aminoanisole, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(o-aminoanisole)-4-deoxy-4′-demethylepipodophyllotoxin.
(2) Separation and purification of 4-N-(o-aminoanisole)-4-deoxy-4′-demethylepipodophyllotoxin (Compound (8)):
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=8:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=4:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(o-aminoanisole)-4-deoxy-4′-demethylepipodophyllotoxin.
4-N-(o-aminoanisole)-4-deoxy-4′-demethylepipodophyllotoxin: white powder: C 28 H 27 NO 8 ; 505, 1 H NMR (300 MHz, CDCl 3 ): δ 2.985-3.019 (m, 1H, 2-H), 3.170 (dd, J=4.8 Hz, 1H, 3-H), 3.783 (s, 6H, 3′, 5′-OCH 3 ), 3.811 (s, 3H, Ar—OCH 3 ), 3.944 (t, J=9.3 Hz, 1H, 11-H), 4.357 (t, J=7.8 Hz, 1H, 11-H), 4.596 (d, J=1.8 Hz, 1H, 4-H), 4.656 (d, J=3.3 Hz, 1H, 1-H), 5.949 (s, 2H, OCH 2 O), 6.341 (s, 2H, ArH), 6.465 (d, J=7.8 Hz, 1H, ArH), 6.522 (s, 1H, ArH), 6.709-6.813 (m, 3H, ArH), 6.879 (t, J=7.5 Hz, 1H, ArH) 13 C NMR (75 MHz, CDCl 3 ): δ 39.058, 42.210, 43.688, 52.419, 55.626, 56.714, 69.252, 101.705, 108.190, 109.069, 109.585, 109.948, 110.031, 117.744, 121.384, 131.007, 131.090, 132.192, 134.256, 137.575, 146.501, 146.668, 147.742, 148.384, 175.231
Embodiment 9: synthesis and purification of 4-N-(4-chloro-2-aminoanisole)-4-deoxy-podophyllotoxin (Compound (9))
(1) Synthesis of 4-N-(4-chloro-2-aminoanisole)-4-deoxy-podophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of podophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of podophyllotoxinand and 2 mol of 4-chloro-2-aminoanisole, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(4-chloro-2-aminoanisole)-4-deoxy-podophyllotoxin.
(2) Separation and purification of 4-N-(4-chloro-2-aminoanisole)-4-deoxy-podophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=10:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=5:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=6:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(4-chloro-2-aminoanisole)-4-deoxy-podophyllotoxin.
4-N-(4-chloro-2-aminoanisole)-4-deoxy-podophyllotoxin: white powder: C 29 H 28 ClNO 8 ; 553, 1 H NMR (300 MHz, CDCl 3 ): δ3.015-3.050 (m, 1H), 3.133 (dd, J=4.8 Hz, 1H), 3.752 (s, 6H), 3.783 (s, 3H), 3.802 (s, 3H), 3.905 (t, J=9.6 Hz, 1H), 4.399 (t, J=7.9 Hz, 1H), 4.601 (d, J=5.1 Hz, 2H), 5.954 (d, J=2.4 Hz, 2H), 6.318 (s, 2H), 6.432 (s, 1H), 6.521 (s, 1H), 6.665 (s, 2H), 6.728 (s, 1H) 13 C NMR (75 MHz, CDCl 3 ): δ38.935, 42.114, 43.844, 52.238, 55.850, 56.461, 61.014, 69.001, 101.815, 108.352, 108.962, 109.548, 110.082, 110.540, 116.848, 126.463, 130.482, 132.085, 135.340, 137.325, 138.495, 145.057, 147.855, 148.542, 152.816, 174.971
Embodiment 10: synthesis and purification of 4-N-(4-chloro-2-aminoanisole)-4-deoxy-4′-demethylepipodophyllotoxin (Compound (10))
(1) Synthesis of 4-N-(4-chloro-2-aminoanisole)-4-deoxy-4′-demethylepipodophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin and 2 mol of 4-chloro-2-aminoanisole, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(4-chloro-2-aminoanisole)-4-deoxy-4′-demethylepipodophyllotoxin.
(2) Separation and purification of 4-N-(4-chloro-2-aminoanisole)-4-deoxy-4′-demethylepipodophyllotoxin (Compound (10)):
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=10:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=7:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(4-chloro-2-aminoanisole)-4-deoxy-4′-demethylepipodophyllotoxin.
4-N-(4-chloro-2-aminoanisole)-4-deoxy-4′-demethylepipodophyllotoxin: white powder: C 28 H 26 ClNO 8 ; 539, 1 H NMR (300 MHz, CDCl 3 ): δ3.039 (m, 1H), 3.114 (dd, J=4.8 Hz, 1H), 3.784 (s, 9H), 3.898 (t, J=9.3 Hz, 1H), 4.376 (t, J=7.8 Hz, 1H), 4.594 (d, J=5.1 Hz, 2H), 5.954 (d, J=3.0 Hz, 2H), 6.333 (s, 2H), 6.436 (s, 1H), 6.524 (s, 1H), 6.672 (s, 2H), 6.728 (s, 1H) 13 C NMR (75 MHz, CDCl 3 ): δ38.863, 42.210, 43.674, 52.251, 55.863, 56.700, 69.001, 101.789, 108.121, 108.985, 109.501, 110.101, 110.547, 126.488, 130.505, 130.784, 132.276, 134.284, 138.524, 145.065, 146.682, 147.798, 148.523, 175.008
Embodiment 11: synthesis and purification of 4-N-(o-aminobenzonitrile)-4-deoxy-podophyllotoxin (Compound (11))
(1) Synthesis of 4-N-(o-aminobenzonitrile)-4-deoxy-podophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of podophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of podophyllotoxinand and 2 mol of o-aminobenzonitrile, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(o-aminobenzonitrile)-4-deoxy-podophyllotoxin.
(2) Separation and purification of 4-N-(o-aminobenzonitrile)-4-deoxy-podophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=8:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=5:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(o-aminobenzonitrile)-4-deoxy-podophyllotoxin.
4-N-(o-aminobenzonitrile)-4-deoxy-podophyllotoxin: white powder: C 29 H 26 N 2 O 7 ; 514, 1 H NMR (300 MHz, CDCl 3 ): δ3.025-3.084 (m, 1H), 3.135 (dd, J=4.8 Hz, 1H), 3.736 (s, 6H), 3.787 (s, 3H), 3.833 (t, J=9.9 Hz, 1H), 4.351 (t, J=7.8 Hz, 1H), 4.629 (d, J=4.8 Hz, 1H), 4.726 (s, 2H), 5.817 (s, 1H), 5.945 (s, 1H), 6.310 (s, 2H), 6.509 (s, 1H) 6.573 (d, J=8.7 Hz, 1H), 6.740 (s, 1H), 6.778 (d, J=7.8 Hz, 1H), 7.432 (t, J=7.5 Hz, 2H) 13 C NMR (75 MHz, CDCl 3 ): δ 38.063, 41.849, 43.734, 52.320, 56.483, 61.011, 68.577, 96.404, 101.927, 108.393, 109.309, 110.147, 110.252, 117.634, 118.210, 129.100, 132.388, 133.733, 134.859, 135.147, 137.372, 147.974, 148.864, 149.387, 152.843, 174.466
Embodiment 12: synthesis and purification of 4-N-(o-aminobenzonitrile)-4-deoxy-4′-demethylepipodophyllotoxin (Compound (12))
(1) Synthesis of 4-N-(o-aminobenzonitrile)-4-deoxy-4′-demethylepipodophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin and 2 mol of o-aminobenzonitrile, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(o-aminobenzonitrile)-4-deoxy-4′-demethylepipodophyllotoxin.
(2) Separation and purification of 4-N-(o-aminobenzonitrile)-4-deoxy-4′-demethylepipodophyllotoxin (Compound (12)):
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=10:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=5:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(o-aminobenzonitrile)-4-deoxy-4′-demethylepipodophyllotoxin.
4-N-(o-aminobenzonitrile)-4-deoxy-4′-demethylepipodophyllotoxin: white powder: C 28 H 24 N 2 O 7 ; 500, 1 H NMR (300 MHz, CDCl 3 ): δ3.065 (m, 1H), 3.123 (dd, J=4.5 Hz, 1H), 3.789 (s, 6H), 3.847 (t, J=9.0 Hz, 1H), 4.351 (t, J=7.5 Hz, 1H), 4.635 (d, J=4.2 Hz, 1H), 4.732 (s, 1H), 4.800 (s, 1H), 5.901 (s, 1H), 5.981 (s, 1H), 6.333 (s, 2H), 6.533 (s, 1H), 6.597 (d, J=8.7 Hz, 1H), 6.740 (s, 1H), 6.801 (t, J=7.5 Hz, 1H), 7.443 (d, J=6.9 Hz, 2H) 13 C NMR (75 MHz, CDCl 3 ): δ 38.556, 41.973, 43.577, 52.363, 56.756, 68.555, 96.573, 101.900, 108.274, 109.222, 110.240, 110.320, 118.218, 129.110, 130.574, 132.555, 133.712, 134.437, 134.832, 146.724, 148.007, 148.914, 149.388, 174.408
Embodiment 13: synthesis and purification of 4-N-(2,6-dichloro-4-aminophenol)-4-deoxy-podophyllotoxin (Compound (13))
(1) Synthesis of 4-N-(2,6-dichloro-4-aminophenol)-4-deoxy-podophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of podophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of podophyllotoxinand and 2 mol of 2,6-dichloro-4-aminophenol, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 12 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(2,6-dichloro-4-aminophenol)-4-deoxy-podophyllotoxin.
(2) Separation and purification of 4-N-(2,6-dichloro-4-aminophenol)-4-deoxy-podophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=30:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=5:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=15:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(2,6-dichloro-4-aminophenol)-4-deoxy-podophyllotoxin.
4-N-(2,6-dichloro-4-aminophenol)-4-deoxy-podophyllotoxin: white powder: C 28 H 25 Cl 2 NO 8 ; 573, 1 H NMR (300 MHz, CDCl 3 ): δ2.862-3.129 (m, 2H), 3.734 (s, 6H), 3.781 (s, 3H), 3.958 (t, J=9.3 Hz, 1H), 4.391 (t, J=7.2 Hz, 1H), 4.537 (d, J=13.5 Hz, 1H), 5.939 (d, J=7.2, 2H), 6.275 (s, 2H), 6.487 (s, 3H), 6.699 (s, 1H) 13 C NMR (75 MHz, CDCl 3 ): δ 38.688, 41.979, 43.723, 53.471, 56.456, 61.016, 68.840, 101.879, 108.308, 109.187, 110.247, 112.492, 122.241, 130.107, 132.003, 135.169, 137.345, 140.734, 141.654, 147.916, 148.627, 152.825, 174.847
Embodiment 14: synthesis and purification of 4-N-(2,6-dichloro-4-aminophenol)-4-deoxy-4′-demethylepipodophyllotoxin (Compound (14))
(1) Synthesis of 4-N-(2,6-dichloro-4-aminophenol)-4-deoxy-4′-demethylepipodophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin and 2 mol of 2,6-dichloro-4-aminophenol, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 12 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(2,6-dichloro-4-aminophenol)-4-deoxy-4′-demethylepipodophyllotoxin.
(2) Separation and purification of 4-N-(2,6-dichloro-4-aminophenol)-4-deoxy-4′-demethylepipodophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=10:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=5:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(2,6-dichloro-4-aminophenol)-4-deoxy-4′-demethylepipodophyllotoxin.
4-N-(2,6-dichloro-4-aminophenol)-4-deoxy-4′-demethylepipodophyllotoxin: white powder: C 27 H 23 Cl 2 NO 8 ; 560, 1 H NMR (300 MHz, CDCl 3 ): δ2.999-3.094 (m, 2H), 3.755 (s, 6H), 3.932 (t, J=9.0 Hz, 1H), 4.365 (t, J=7.2 Hz, 1H), 4.537 (s, 1H), 5.917 (d, J=11.1, 2H), 6.292 (s, 2H), 6.497 (s, 3H), 6.709 (s, 1H) 13 C NMR (75 MHz, CDCl 3 ): δ 38.661, 42.062, 43.556, 53.345, 56.704, 68.906, 101.851, 108.062, 109.213, 110.214, 112.408, 122.293, 130.217, 130.669, 132.164, 134.248, 140.613, 141.816, 146.669, 147.807, 148.547, 175.063
Embodiment 15: synthesis and purification of 4-N—(N,N-dimethylamino metanil)-4-deoxy-podophyllotoxin (Compound (15))
(1) Synthesis of 4-N—(N,N-dimethylamino metanil)-4-deoxy-podophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of podophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of podophyllotoxinand and 2 mol of N,N-dimethylamino metanil, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N—(N,N-dimethylamino metanil)-4-deoxy-podophyllotoxin.
(2) Separation and purification of 4-N—(N,N-dimethylamino metanil)-4-deoxy-podophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=4:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=2:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N—(N,N-dimethylamino metanil)-4-deoxy-podophyllotoxin.
4-N—(N,N-dimethylamino metanil)-4-deoxy-podophyllotoxin: white powder: C 30 H 32 N 2 O 7 ; 532, 1 H NMR (300 MHz, CDCl 3 ): δ2.936 (s, 6H), 2.996 (d, J=2.7 Hz, 1H), 3.143 (dd, J=4.5 Hz, 2H), 3.757 (s, 6H), 3.804 (s, 3H), 4.049 (t, J=9.6 Hz, 1H), 4.399 (t, J=8.1 Hz, 1H), 4.586 (d, J=4.5 Hz, 1H), 4.688 (s, 1H), 5.947 (d, J=4.5, 4H), 6.231 (d, J=8.1 Hz, 1H), 6320 (s, 2H), 6.513 (s, 1H), 6.800 (s, 1H), 7.092 (t, J=8.1 Hz, 1H) 13 C NMR (75 MHz, CDCl 3 ): δ 39.050, 41.101, 42.049, 43.820, 52.676, 56.497, 61.016, 69.468, 101.768, 104.055, 108.420, 109.564, 110.080, 130.455, 131.097, 131.920, 135.518, 137.317, 147.805, 148.390, 148.697, 152.797, 175.265
Embodiment 16: synthesis and purification of 4-N—(N,N-dimethylamino metanil)-4-deoxy-4′-demethylepipodophyllotoxin (Compound (16))
(1) Synthesis of 4-N—(N,N-dimethylamino metanil)-4-deoxy-4′-demethylepipodophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin and 2 mol of N,N-dimethylamino metanil, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N—(N,N-dimethylamino metanil)-4-deoxy-4′-demethylepipodophyllotoxin.
(2) Separation and purification of 4-N—(N,N-dimethylamino metanil)-4-deoxy-4′-demethylepipodophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=12:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=6:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N—(N,N-dimethylamino metanil)-4-deoxy-4′-demethylepipodophyllotoxin.
4-N—(N,N-dimethylamino metanil)-4-deoxy-4′-demethylepipodophyllotoxin: white powder: C 29 H 30 N 2 O 7 ; 518, 1 H NMR (300 MHz, CDCl 3 ): δ2.928 (s, 6H), 2.978 (d, J=3.3 Hz, 1H), 3.119 (dd, J=4.5 Hz, 2H), 3.777 (s, 6H), 4.032 (t, J=9.6 Hz, 1H), 4.372 (t, J=7.8 Hz, 1H), 4.564 (d, J=4.8 Hz, 1H), 4.672 (d, J=2.7 Hz, 1H), 5.933 (d, J=5.7, 4H), 6.222 (d, J=8.1 Hz, 1H), 6326 (s, 2H), 6.501 (s, 1H), 6.793 (s, 1H), 7.084 (t, J=8.1 Hz, 1H) 13 C NMR (75 MHz, CDCl 3 ): δ 38.855, 40.905, 41.979, 43.499, 52.495, 56.567, 69.356, 101.600, 103.846, 107.974, 109.410, 109.926, 130.274, 130.846, 130.999, 131.948, 134.067, 146.508, 147.609, 148.209, 148.586, 151.654, 175.237
Embodiment 17: synthesis and purification of 4-N-(2-ethyl-5-nitroaniline)-4-deoxy-podophyllotoxin (Compound (17))
(1) Synthesis of 4-N-(2-ethyl-5-nitroaniline)-4-deoxy-podophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of podophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of podophyllotoxinand and 2 mol of 2-ethyl-5-nitroaniline, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(2-ethyl-5-nitroaniline)-4-deoxy-podophyllotoxin.
(2) Separation and purification of 4-N-(2-ethyl-5-nitroaniline)-4-deoxy-podophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=10:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=5:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column; glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(2-ethyl-5-nitroaniline)-4-deoxy-podophyllotoxin.
4-N-(2-ethyl-5-nitroaniline)-4-deoxy-podophyllotoxin: white powder: C 30 H 30 N 2 O 9 ; 562, 1 H NMR (300 MHz, CDCl 3 ): δ 1.237 (t, J=7.2 Hz, 3H), 2.449-2.522 (m, 2H), 3.116 (s, 2H), 3.759 (s, 6H), 3.799 (s, 3H) 4.002 (d, J=5.1 Hz, 1H), 4.452 (t, J=3.6 Hz, 1H), 4.618 (s, 1H), 4.826 (s, 1H), 5.967 (d, J=1.2 Hz, 2H), 6.309 (s, 2H), 6.546 (s, 1H), 6.706 (s, 1H), 7.211 (d, J=8.4 Hz, 1H), 7.317 (t, J=1.5 Hz, 1H), 7.609 (d, J=8.4 Hz, 1H) 13 C NMR (75 MHz, CDCl 3 ): δ 12.543, 24.311, 38.656, 42.178, 43.810, 52.658, 56.466, 61.018, 68.836, 101.936, 103.282, 108.321, 109.037, 110.354, 113.561, 128.880, 129.882, 132.402, 134.850, 137.470, 145.487, 147.663, 148.121, 152.903, 174.607
Embodiment 18: synthesis and purification of 4-N-(2-ethyl-5-nitroaniline)-4-deoxy-4′-demethylepipodophyllotoxin (Compound (18))
(1) Synthesis of 4-N-(2-ethyl-5-nitroaniline)-4-deoxy-4′-demethylepipodophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin and 2 mol of 2-ethyl-5-nitroaniline, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(2-ethyl-5-nitroaniline)-4-deoxy-4′-demethylepipodophyllotoxin.
(2) Separation and purification of 4-N-(2-ethyl-5-nitroaniline)-4-deoxy-4′-demethylepipodophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=10:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=5:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(2-ethyl-5-nitroaniline)-4-deoxy-4′-demethylepipodophyllotoxin.
4-N-(2-ethyl-5-nitroaniline)-4-deoxy-4′-demethylepipodophyllotoxin: white powder: C 28 H 26 N 2 O 7 ; 502, 1 H NMR (300 MHz, CDC 13 ): δ 1.248 (s, 3H), 2.549 (d, J=7.2 Hz, 2H), 3.129 (s, 2H), 3.809 (s, 6H), 4.004 (s, 1H), 4.453 (s, 1H), 4.631 (s, 1H), 4.849 (s, 1H), 5.986 (d, J=2.4 Hz, 2H), 6.339 (s, 2H), 6.563 (s, 1H), 6.724 (s, 1H), 7.231 (d, J=9.3 Hz, 1H), 7.342 (s, 1H), 7.634 (d, J=9.6 Hz, 1H) 13 C NMR (75 MHz, CDCl 3 ): δ 12.571, 24.340, 38.599, 42.293, 43.667, 52.672, 56.710, 68.879, 101.950, 103.282, 108.063, 109.037, 110.354, 113.518, 128.894, 129.911, 130.440, 132.662, 134.377, 134.778, 145.544, 146.733, 147.678, 148.079, 148.809, 174.779
Embodiment 19: synthesis and purification of 4-N-(2 2′-diaminodiphenylsulfide)-4-deoxy-podophyllotoxin (Compound (19))
(1) Synthesis of 4-N-(2 2′-diaminodiphenylsulfide)-4-deoxy-podophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of podophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of podophyllotoxinand and 2 mol of 2 2′-diaminodiphenylsulfide, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(2 2′-diaminodiphenylsulfide)-4-deoxy-podophyllotoxin.
(2) Separation and purification of 4-N-(2 2′-diaminodiphenylsulfide)-4-deoxy-podophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=10:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=5:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(2 2′-diaminodiphenylsulfide)-4-deoxy-podophyllotoxin.
4-N-(2 2′-diaminodiphenylsulfide)-4-deoxy-podophyllotoxin: white powder: C 34 H 32 N 2 O 7S ; 612, 1 H NMR (300 MHz, CDCl 3 ): δ2.586 (dd, J=5.1 Hz, 1H, 3-H), 2.8077-2.866 (m, 1H, 2-H), 3.383 (t, J=9.6 Hz, 1H, 11-H), 3.735 (s, 6H, 3′, 5′-OCH 3 ), 3.789 (s, 3H, 4′-OCH 3 ), 4.144 (t, J=7.9 Hz, 1H, 11-H), 4.482 (d, J=5.1 Hz, 1H, 1-H), 4.721 (s, 1H, 4-H), 5.946 (d, J=5.1 Hz, 2H, OCH 2 O), 6.279 (s, 2H, ArH), 6.424 (s, 1H, ArH), 6.526 (d, J=8.1 Hz, 1H, ArH), 6.625 (s, 2H, ArH), 6.714 (t, J=7.5 Hz, 1H, ArH), 7.037 (d, J=7.8 Hz, 2H, ArH), 7.228 (t, J=9.0 Hz, 1H, ArH), 7.513 (d, J=7.2 Hz, 1H, ArH) 13 C NMR (75 MHz, CDCl 3 ): δ 38.6648, 41.6062, 43.6227, 51.0699, 56.3359, 60.8768, 66.6776, 101.5862, 108.2271, 109.1747, 109.4324, 109.7205, 115.4507, 116.7025, 117.0653, 119.5453, 129.6658, 130.3405, 131.7809, 133.1682, 135.5941, 137.1178, 146.6470, 147.4885, 148.2067, 152.6208, 174.7949
Embodiment 20: synthesis and purification of 4-N-(2 2′-diaminodiphenylsulfide)-4-deoxy-4′-demethylepipodophyllotoxin (Compound (20))
(1) Synthesis of 4-N-(2 2′-diaminodiphenylsulfide)-4-deoxy-4′-demethylepipodophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin and 2 mol of 2 2′-diaminodiphenylsulfide, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(2 2′-diaminodiphenylsulfide)-4-deoxy-4′-demethylepipodophyllotoxin.
(2) Separation and purification of 4-N-(2 2′-diaminodiphenylsulfide)-4-deoxy-4′-demethylepipodophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=10:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=5:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(2 2′-diaminodiphenylsulfide)-4-deoxy-4′-demethylepipodophyllotoxin.
4-N-(2 2′-diaminodiphenylsulfide)-4-deoxy-4′-demethylepipodophyllotoxin: white powder: C 33 H 30 N 2 O 7 S; 598, 1 H NMR (300 MHz, CDCl 3 ): δ 2.841 (s, 1H, 2-H), 3.402 (t, J=9.6 Hz, 1H, 3-H), 3.771 (s, 6H, 3′, 5′-OCH 3 ), 3.944 (t, J=9.3 Hz, 1H, 11-H), 4.357 (t, J=7.8 Hz, 1H, 11-H), 4.387 (d, J=1.8 Hz, 1H, 4-H), 4.514 (d, J=3.3 Hz, 1H, 1-H), 5.926 (s, 2H, OCH 2 O), 6.291 (s, 2H, ArH), 6.465 (d, J=7.8 Hz, 1H, ArH), 6.5955 (s, 1H, ArH), 6.709-6.813 (m, 3H, ArH), 6.874 (t, J=7.5 Hz, 1H, ArH) 13 C NMR (75 MHz, CDCl 3 ): δ 38.725, 41.862, 43.592, 53.691, 56.714, 68.815, 101.691, 108.134, 109.344, 109.513, 109.893, 115.675, 117.222, 117.827, 119.768, 129.799, 130.460, 130.980, 132.134, 133.302, 134.258, 135.721, 146.651, 146.849, 147.608, 148.368, 175.012
Embodiment 21: synthesis and purification of 4-N-(2-aminobenzotrifluoride)-4-deoxy-podophyllotoxin (Compound (21))
(1) Synthesis of 4-N-(2-aminobenzotrifluoride)-4-deoxy-podophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of podophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of podophyllotoxinand and 2 mol of 2 2′-diaminodiphenylsulfide, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(2-aminobenzotrifluoride)-4-deoxy-podophyllotoxin.
(2) Separation and purification of 4-N-(2-aminobenzotrifluoride)-4-deoxy-podophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=10:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=5:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(2-aminobenzotrifluoride)-4-deoxy-podophyllotoxin.
4-N-(2-aminobenzotrifluoride)-4-deoxy-podophyllotoxin: white powder: C 29 H 26 F 3 NO 7 ; 557, 1 H NMR (300 MHz, CDCl 3 ): δ 3.112 (s, 2H, 2-H, 3-H), 3.794 (s, 6H, 3′, 5′-OCH 3 ), 3.846 (s, 3H, 4′-OCH 3 ), 3.935 (t, J=9.3 Hz, 1H, 11-H), 4.411 (t, J=7.8 Hz, 1H, 11-H), 4.668 (d, J=1.8 Hz, 1H, 4-H), 4.834 (d, J=3.3 Hz, 1H, 1-H), 6.009 (s, 2H, OCH 2 O), 6.363 (s, 2H, ArH), 6.576 (s, 1H, ArH), 6.672 (d, J=8.1 Hz, 1H, ArH), 6.786 (s, 1H, ArH), 6.864 (t, J=7.5 Hz, 1H, ArH), 7.452 (t, J=7.2 Hz, 1H, ArH), 7.521 (d, J=7.5 Hz, 1H, ArH) 13 C NMR (75 MHz, CDCl 3 ): δ 38.806, 42.122, 43.800, 52.466, 56.545, 61.019, 68.925, 101.899, 108.567, 109.271, 110.256, 111.353, 117.655, 127.488, 129.767, 132.229, 133.650, 135.212, 144.961, 148.098, 148.787, 152.909, 174.643
Embodiment 22: synthesis and purification of 4-N-(2-aminobenzotrifluoride)-4-deoxy-4′-demethylepipodophyllotoxin (Compound (20))
(1) Synthesis of 4-N-(2-aminobenzotrifluoride)-4-deoxy-4′-demethylepipodophyllotoxin: taking 1 mol of activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin (prepared in preparatory test example 1), which is then dried in vacuo at 45° C. for 2 hours; under protection of nitrogen, dried dichloromethane were added into a 4-necked flask, then adding dried activated product of position 4 of C-ring of 4′-demethylepipodophyllotoxin and 2 mol of 2-aminobenzotrifluoride, adding 0.36 g of BaCO 3 , stirring for reaction at 25° C. for 24 hours; reaction liquid is rotary dried, then obtaining crude product of 4-N-(2-aminobenzotrifluoride)-4-deoxy-4′-demethylepipodophyllotoxin.
(2) Separation and purification of 4-N-(2-aminobenzotrifluoride)-4-deoxy-4′-demethylepipodophyllotoxin:
Separation and Purification Using Silica Gel Column Chromatography and Gel Column Chromatography:
(A) using normal phase silica gel column (normal phase silica gel: China Qingdao Haiyang Chemical Co., Ltd, HG/T2354-92; separation system: Swiss Buchi isocratic fast chromatography system; chromatographic column: Swiss Buchi glass column C-690 with length of 460 mm and inner diameter of 15 mm) or a similar polar column separation; taking system of chloroform:acetone=10:1 as eluent, with sample volume of 2 ml, constant flow rate of 1.0 ml/min; each of 2 ml of eluent as a fraction were collected. Using normal phase silica gel thin layer (efficient silica gel thin layer by Merck, Germany) or thin layer with similar polarity, each of fractions are viewed; taking system of chloroform:acetone=5:1 as a developing agent, fractions with Rf value of 0.5 are merged; the sample after merged is subjected to vacuum drying, stored at 4° C. in the refrigerator under dark conditions, as samples to be purified.
(B) separating by gel column chromatography (gel: Sephadex LH-20; Separation column: glass column with length 480 mm and inner diameter of 30 mm); loading processed gel Sephadex LH-20 into column by wet method to be balanced with methanol. The sample to be purified is dissolved in 6 ml of methanol, adsorbed at flow rate of 0.6 ml/min of sample and then eluted at flow rate of 0.6 ml/min with 600 ml of methanol, eluate was collected to a bottle every 10 ml, each fraction is checked with normal phase silica gel thin layer (effective silica gel thin layer by Merck, Germany) or thin layer with similar polar; adopting system with chloroform:acetone=5:1 as developing solvent, fractions with Rf value of 0.5 are combined; sample of white powder from vacuum drying is 4-N-(2-aminobenzotrifluoride)-4-deoxy-4′-demethylepipodophyllotoxin.
4-N-(2-aminobenzotrifluoride)-4-deoxy-4′-demethylepipodophyllotoxin: white powder: C 28 H 24 F 3 NO 7 ; 543, 1 H NMR (300 MHz, CDCl 3 ): δ 3.088 (s, 2H, 2-H, 3-H), 3.810 (s, 6H, 3′, 5′-OCH 3 ), 3.916 (t, J=9.3 Hz, 1H, 11-H), 4.411 (t, J=6.3 Hz, 1H, 11-H), 4.638 (d, J=3.6 Hz, 1H, 4-H), 4.821 (s, 1H, 1-H), 5.995 (s, 2H, OCH 2 O), 6.369 (s, 2H, ArH), 6.562 (s, 1H, ArH), 6.662 (d, J=1.0 Hz, 1H, ArH), 6.771 (s, 1H, ArH), 6.850 (t, J=7.5 Hz, 1H, ArH), 7.441 (t, J=7.2 Hz, 1H, ArH), 7.509 (d, J=7.5 Hz, 1H, ArH) 13 C NMR (75 MHz, CDCl 3 ): δ 38.795, 42.196, 43.631, 52.480, 56.770, 68.925, 101.871, 108.230, 109.229, 110.256, 111.367, 117.613, 127.474, 129.767, 132.398, 133.650, 134.410, 144.975, 146.733, 148.041, 148.776, 152.909, 174.714
Experiment 1: Test of Compounds of Embodiment of the Present Invention on Inhibiting Tumor Cell Activity
1) Test Materials
1, compounds for the test: the compounds prepared in embodiments 1 to 22, noted with compounds (1) to (22);
2, compounds for comparison: podophyllotoxin and 4′-demethylepipodophyllotoxins;
3, cell lines: Hela, BGC823, A549 cell line and normal human hepatocytes which are available from Wu Han boster Co., Ltd.;
2) Test Method
Hela, BGC823, A549 cell line and normal human hepatocytes in logarithmic growth phase are subjected to 1000 rpm centrifugation for 5 min, supernatant is then discarded, moderate medium is suspended, the cell concentration is adjusted to 3.5×10 4 /well, the cells were seeded in 96-wells culture plate, and following experimental groups are set:
a negative control group; 22 test groups with same concentration (ie: groups of Compound (1) to Compound (22)); 2 control groups: groups of podophyllotoxin, 4′-demethylepipodophyllotoxin and etoposide.
Taking RPMI1640 containing 10% of calf serum as nutrient solution, 0.10 mL of cells per well is incubated under conditions of 37 V, 5% CO2 and saturated humidity for 24 h to nearly be covered, then the nutrient solution is discarded. For the 22 test groups, 0.10 M of nutrient solution of RPMI1640 with 10% calf serum containing same amount of the compound (1) to compound (22) is added respectively; for groups of podophyllotoxin, 4′-demethylepipodophyllotoxin and etoposide, 0.10 M of nutrient solution of RPMI1640 with 10% calf serum is added containing podophyllotoxin, 4′-demethylepipodophyllotoxin and etoposide, respectively; amount of podophyllotoxin, 4′-demethylepipodophyllotoxin or etoposide is same as the amount of the compounds (1) to (22); for the negative control group, DMSO with a final concentration of 0.5% is added; for each group, three complex wells are set, cultivation is continued for 48 h, 10 μl of MTT with 5 mg/ml is added to each well, then put at 37° C. for 4 h. 100 μl of DMSO is added to each well, then vibrated at 37° C. by shaker table for 30 min, then measuring absorbance (OD) at 492 nm, calculating MTT ratio=OD value of drug group/OD value of the negative control group.
3) Test Results
Test results are shown in Table 1. From Table 1, anti-tumor activity of the compounds of aniline-substituted podophyllotoxin-type derivatives of embodiments of the invention to the Hela, BGC823, A549 cell lines is much better than those of podophyllotoxin, and 4′-demethylepipodophyllotoxin.
TABLE 1
IC 50 values of aniline-substituted podophyllotoxin-type derivatives
to in vitro tumor cell lines and normal cell lines
Cytotoxic activity (IC 50 , μM) [a]
Compounds
Hela [b]
BGC823 [b]
A549 [b]
1
1.26 ± 0.37
0.62 ± 0.13
1.75 ± 0.83
2
2.01 ± 1.21
1.77 ± 0.37
5.21 ± 0.41
3
2.57 ± 0.87
3.16 ± 1.11
1.97 ± 0.32
4
1.97 ± 0.16
0.40 ± 0.17
3.04 ± 0.23
5
7.07 ± 1.63
17.18 ± 0.34
2.32 ± 0.06
6
0.56 ± 0.17
3.52 ± 0.43
2.20 ± 0.25
7
13.37 ± 3.31
6.26 ± 0.36
3.41 ± 0.10
8
1.72 ± 0.30
5.63 ± 1.20
15.27 ± 0.45
9
8.07 ± 1.81
1.24 ± 0.06
1.71 ± 0.26
10
1.35 ± 0.18
1.61 ± 0.37
3.72 ± 0.41
11
16.91 ± 1.48
>100
1.02 ± 0.07
12
1.92 ± 1.21
7.91 ± 0.59
11.64 ± 1.63
13
17.57 ± 2.39
1.58 ± 0.16
9.66 ± 0.35
14
14.67 ± 0.42
13.82 ± 1.42
9.41 ± 0.59
15
1.33 ± 0.20
2.59 ± 0.21
>100
16
1.06 ± 0.57
1.52 ± 0.39
2.08 ± 0.26
17
6.01 ± 0.71
4.24 ± 0.79
1.4 ± 0.28
18
7.89 ± 0.31
27.12 ± 0.24
4.28 ± 0.48
19
2.14 ± 0.21
6.46 ± 0.33
23.24 ± 0.72
20
16.31 ± 0.39
2.17 ± 0.23
1.42 ± 0.12
21
2.45 ± 3.04
23.24 ± 0.76
2.11 ± 0.05
22
5.89 ± 0.48
6.01 ± 0.12
9.72 ± 0.98
podophyl-
55 ± 0.24
75 ± 0.73
67 ± 0.24
lotoxin
4′-demethyl-
49 ± 0.38
63 ± 0.49
52 ± 0.85
epipodophyl-
lotoxin
VP-16
13.15 ± 1.65
22.32 ± 2.97
31.05 ± 1.72
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The present invention discloses an anilino-substituted podophyllin derivative having antitumor activity, method for preparation thereof, and use thereof. By means of anilino reactions, the present invention introduces 4-chloro-3-methylaniline, 3-fluoro-4-methoxyaniline, 4,4′-diaminodiphenylmethane, o-anisidine, 4-chloro-2-aminoanisole, anthranilonitrile, 2,6-dichloro-4-aminophenol, N,N-dimethylamino meta-aniline, 2-ethyl-5-nitroaniline, 2 2′-diaminodiphenylsulfide, or 2-aminobenzotrifluoride into position 4 of the active C-ring of podophyllotoxin or 4′-demethylepipodophyllotoxin to obtain the aniline-substituted podophyllotoxin derivative shown in formula (V); by means of multi-pathway and multi-target effects on tumor cells, said derivative has significantly increased antitumor activity, and can be prepared as an antineoplastic drug and applied in clinical antitumor therapy.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit and priority of DE 10 2010 023 156.8, filed Jun. 2, 2010. The entire disclosure of the above application is incorporated herein by reference.
FIELD
The invention relates to cell-based in vitro assays and test systems, in particular for examining viral infections and active ingredients with anti-viral action. It provides a multi-layered biological tissue as an in vitro test system for virus infections and substances with an anti-viral action. The invention also provides methods and means for finding an anti-viral active ingredient in an in vitro assay.
BACKGROUND
This section provides background information related to the present disclosure which is not necessarily prior art.
A multiplicity of infectious diseases in humans or animals are caused by viruses. Viruses do not have their own metabolism, which makes the causal treatment of viral infectious diseases difficult. In particular, they cannot be treated by antibiotics. Viricides that is, drugs that destroy viruses, are not currently available. Often a patient's immune system is not able to eradicate the infecting virus alone. Known substances with an antiviral action, so-called virustatics, prevent the spread or multiplication of viruses by various active mechanisms, which are connected with the infection cycle or multiplication cycle of the viruses. Known virustatics act in particular as DNA polymerase inhibitors. Known substances with nucleotide action are idoxuridine, aciclovir and ganciclovir and derivatives thereof. Other polymerase inhibitors are, for example, poscarnet and ribavirin.
Infections with the herpes simplex virus (HSV) are among the most common diseases in humans. More than 90% of the total world population are infected with this virus. Herpes simplex viruses (HSV) are divided into two closely related virus species (human herpes virus 1 (HSV1) and human herpes virus 2 (HSV2). The herpes viruses cause very different diseases of the herpes simplex, including herpes simplex encephalitis and neonatal herpes. The most widespread are herpes labialis and genital herpes.
A characteristic of HSV is persistence. After initial infection of the cells of the animal or human host organism, particularly of epithelial cells of the mucous membrane, the virus spreads into neuronal cells, in particular cells of sensory neurons, which innervate the primarily infected region. The viruses reach the ganglia via retrograde axonal transport and typically appear there in a latent state. The virus DNA persists, essentially unrecognized by the host's immune system, as a circular episome in the nucleus of the ganglia. During the latency phase, no virus replication takes place, the infected host is symptom-free. A reactivation of the latent viruses is triggered by stressors, such as a weakened immune system, exposure to sunlight, inflammatory events, hormonal or psychological effects (neuroendocrinological conditions) or nerve irritation. Virions thereby migrate axonally out of the ganglia back into the periphery and reinfect the tissue there, in particular the epithelial cells. The typical clinical picture of a herpes infection is shown by a lytic replication cycle in the epithelial tissue, and the tissue destruction resulting therefrom. The known therapy of a herpes infection is inadequate. Known virustatics can only relieve the symptoms and shorten the infection period but are not able to end the persistence of the viruses in the ganglia cells (eradication).
Many of the studies hitherto carried out on the latency mechanisms and reactivation analyses are obtained with the aid of mammalian cell lines. However, these test systems lack direct applicability to the in vivo situation in the patient. Consequently, animal experiments continue to be used in studies of the infection and latency mechanisms, but in particular in the development of active ingredients. It is desirable to develop in vitro test systems that permit a direct applicability of the results obtained thereby to the situation in the infected patient and that can replace animal studies.
With the aid of standardized three-dimensional in vitro skin equivalents, which are reconstituted from primary skin cells and/or skin cell lines, human skin can be reproducibly replicated. Physiologically such skin equivalents are largely comparable to native skin. As is known, they are used as in vitro tests systems for skin tissue (in vitro skin model).
SUMMARY
This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.
The technical problem on which the invention is based was to provide an in vitro test system, by means of which in particular latency mechanisms and reactivation analyses in virus infections, in particular with HSV infections, can be carried out and the results thereof can be applied in particular directly to the in vivo situation in a human or animal organism. In particular the in vitro test system should render possible a screening of active substances to find substances with an anti-viral action.
The technical problem is fully solved by the provision of a multi-layered biological in vitro tissue, that contains a dermis layer and preferably also an epidermis layer, wherein the dermis layer is essentially made up of a collagen biomatrix with fibroblasts embedded, that is, integrated, therein or containing them. The epidermis layer arranged thereon contains essentially epithelial cells, that is, in particular keratinocytes. Dermis layer and epithelial layer can form a model system that is similar or equivalent to human skin tissue. The in vitro test model according to the invention is based accordingly on an in vitro skin model. According to the invention, this multi-layered biological tissue is characterized above all in that at least in the dermis layer thereof, in addition to the fibroblasts, in particular virally infected, but in particular latently infected, neuronal cells are integrated.
Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
In a special embodiment the viral infection of the neuronal cells is an active or reactivatable latent infection with the herpes simplex virus (HSV), in particular with the herpes simplex virus 1 (HSV1). However, the invention is not restricted to this virus type. In other preferred embodiments of the in vitro test system, the virus is selected from: CMV, VZV, HBV, influenza A, influenza B, RSV and HCV.
In a special embodiment, the neuronal cells embedded into the in vitro test system are the cell line of pheochromocytoma cells; in particular these are cells of type PC12 (pheochromocytoma 12).
The invention therefore provides above integrating preferably latently virally infected neuronal cells into a multi-layered, so-called three-dimensional in vitro skin equivalent in order to obtain a new kind of in vitro test system. Above all the progression and the mechanisms of a viral infection, that is, in particular the reactivation of a latent virus infection and the interaction of the infected neuronal cells with the skin cells can be tested therewith. This makes it possible compared to known test systems to carry out tests of this type more simply, more reliably and also more informatively, but in particular screenings for the purpose of finding and characterizing potential substances with anti-viral action.
In a special embodiment in the epidermis layer of the in vitro test system the epithelial cells are selected from cells of keratinocyte cell lines and/or primary keratinocytes. In a special variant thereof, the epithelial cells originate from the keratinocyte cell line HaCaT (human adult low calcium high temperature) or are cells derived therefrom. In particular HaCaT cells surprisingly show a differentiation behavior largely corresponding to the in vivo state of a skin tissue and can thus improve the applicability of the findings obtained by means of the in vitro test system according to the invention to the in vivo situation. Particularly in connection with an epidermis layer built up largely or exclusively of HaCaT cells or cells derived therefrom, it is provided that the in vitro tissue is cultivated in culture medium that contains at least one or more of the culture factors selected from TGF-α, GM-CSF and IL-1α. Such culture factors are suitable for further improving the approximation of the cell status to the in vivo situation.
In a special variant, the keratinocytes used to build up the epidermis layer are alternatively or additionally genetically modified: for the purpose of testing the signal paths in a virus infection, the keratinocytes are preferably deficient for one or more pattern recognition receptors (PRR), that is, they represent a knock down mutant or optionally a knock out mutant for receptors of this type. In a special variant, the deficient PRR is selected from the group of the toll-like receptors (TLR): TLR2, TLR5 and TLR9 are preferred. Accordingly, the invention in a special embodiment provides an in vitro test system, wherein the epidermis layer contains keratinocytes or is built up thereof, which are knock down mutants or knock out mutants for one or more TLR, in particular for TLR2, TLR5 and/or TLR9. In order to achieve this, in particular HaCaT cells with small interfering RNA (siRNA) for TLR coding plasmides can be transfected in a manner known per se (nucleofection, RNA interference, (RNAi) method). Through siRNA cellular proteins can be suppressed, that is, “knocked down” in a manner known per se. A complete suppression of the proteins does not need to be achieved; the invention does not require a complete suppression (knock out) in this embodiment. The invention is not restricted to this embodiment for producing a knock down mutant. The knock down mutants HaCaTΔTLR2, HaCaTΔTLR5 and HaCaTΔTLR9 and knock down combinations (double-mutants, multiple mutants) thereof are preferred. The invention is not limited to these knock down mutants.
In an alternative variant, the epidermis layer, additionally or exclusively, contains primary epithelial cells, which obtained in particular in preceding steps, from tissue of the oral mucosa or tissue comparable thereto from the intestine, gastric mucosa, skin, cornea, trachea and other epithelial tissues. A particular source of epithelial cells is represented by human donor tissue, in particular foreskin (prepuce).
In a special embodiment, the dermis layer of the in vitro test tissue is built up of a collagen biomatrix, which essentially contains type-I collagen or preferably is composed thereof. Type-I collagen is provided in a preferred variant as largely or essentially native collagen. To this end, in particular the collagen is extracted as freshly as possible and without denaturing interim steps from collagen-containing tissue, in particular from tissue rich in type-1 collagen, for example, rat tail sinews, lightly acetous, or alternatively extracted by means of urea and preferably brought to gelation by raising the pH value and/or by renaturing in buffer, in particular by the addition of buffered cell suspension, in order to obtain a collagen biomatrix, in particular with cells embedded therein, particularly fibroblasts, preferably with neuronal cells additionally embedded therein according to the invention, which forms the dermis layer. In the production/provision of the collagen biomatrix, preferably denaturing steps, such as salt precipitation, strong alkalinity or acidity, thermal denaturing as well as lyophilization are avoided or ruled out completely. In order to obtain a native collagen structure, the collagen-containing starting tissue is preferably extracted at low temperature with low acid concentration, in particular pH 4 or more, for a comparatively long time, in particular 3 or 4 days and gelated by dilution with buffer solution and/or by increasing the temperature, for example, at room temperature.
In a special variant, the dermis layer contains primary fibroblasts, preferably human primary fibroblasts. These are preferably obtained fresh from human donor tissue, for example, foreskin tissue. To this end, in a first step in the donor tissue the skin layers are separated and isolated fibroblasts are recultivated from the isolated dermis layer of the donor tissue and embedded in the collagen biomatrix, in order to form a reconstituted dermis layer.
In a further special embodiment, in addition, immunocompetent cells, that is, in particular immune cells, are integrated into the test tissue according to the invention. The significance of the in vitro test system based on the tissue according to the invention can be improved thereby. Still inactive epidermally located dendritic cells, particularly preferably Langerhans cells, are hereby preferred in particular. The immunocompetent cells are used in particular to support the intercellular communication in the test tissue, in that they process antigens and optionally can present further immune cells. The invention provides thereby that the immunocompetent cells are seeded on or in the dermis layer or are embedded therein together with the fibroblasts.
The subject matter of the invention is also a method for producing a multi-layered biological tissue, which can be used in particular as an in vitro test system, in particular for examining virus infections and/or for screening active ingredients with an anti-viral action. In a first process step, to produce a multi-layered base tissue, a collagen biomatrix is provided. This is preferably produced as described herein. Preferably, the collagen biomatrix contains essentially type-I collagen in non-denatured form or is composed thereof. According to the invention the fibroblast cells characterized in more detail elsewhere herein are embedded in the biomatrix. To this end, the fibroblasts are suspended in the not yet hardened gelated collagen solution: alternatively, the collagen solution is mixed with a suspension of fibroblasts in buffer and/or cell culture medium. The collagen biomatrix hardens with the fibroblasts suspended therein.
According to the invention, it is provided that in addition preferably virally infected neuronal cells, as are characterized in more detail elsewhere herein, are embedded in the dermis layer. The embedding of the neuronal cells is preferably carried out together with the embedding of the fibroblasts. To this end, fibroblasts as well as the preferably (latently) virally infected neuronal cells are suspended, and the collagen solution hardens together with the cells to form a collagen biomatrix with fibroblasts and neuronal cells embedded therein. This collagen biomatrix with the cells embedded therein thus forms the dermis layer of the in vitro test tissue according to the invention.
Furthermore, in addition an epidermal layer is built up on the dermis layer. This is carried out in particular by layering the dermis with keratinocytes, which are characterized in more detail elsewhere herein. Thereby it is particularly provided that before the application of the keratinocytes, the dermal collagen matrix is firstly layered with fibronectin or a similar component, which can form the basement membrane between the dermis and the epidermal layer placed thereon. Thus a multi-layered biological in vitro test tissue, containing fibroblasts and virally infected neuronal cells as well as epithelial cells, that is, keratinocytes, is obtained.
In a special embodiment of the method, the neuronal cells are infected before being embedded into the test tissue by infection with a virus, in the invention variant described in more detail here, with the herpes simplex virus 1 (HSV1). This can be carried out in a manner known per se. A latent and reactivatable virus infection in the neuronal cells is obtained thereby. The in vitro test model in this embodiment according to the invention is thus given a latency forming neuronal component.
The latent infection can be verified by molecular biological analysis. In a preferred variant, to this end a quantitative RT-PCR is carried out. It is thereby preferably specifically tested for latency-associated transcripts (LAT genes) regulating miRNA. Of course, the verification of the provided latent virus infection is not limited to these methods.
The in vitro test tissue is firstly preferably cultivated in submerse culture in a manner known per se. This cultivation phase lasts approximately 6 days. After mechanical stabilization and/or conclusion of initial phases of the build up of intact tissue layers through the introduced cells, this is followed by a cultivation in the so-called airlift culture (airlift phase). The airlift phase lasts for approximately 14 to 15 days. During the airlift phase, preferably the hornification of the keratinocytes (epidermis) is promoted, in particular by means of calcium-rich medium.
The subject matter of the invention is also a biological in vitro test tissue, which can be produced or preferably is directly produced by means of the production method described herein. The invention does not rule out further processing steps to provide the usable in vitro tissue.
For the production of the in vitro test tissue and for the use thereof according to the invention, particularly in connection with the screening of active ingredients, the invention provides that a specific reactivation of the virus infection takes place in the latently virally infected neuronal cells. In a particular embodiment this is carried out by exposure at least once, preferably twice, with at least one reactivating stressor. Preferably, this stressor is selected from energy-rich electromagnetic radiation, in particular UVB radiation (UVB exposure) and/or thermal action (heat exposure). The possibilities of the reactivation of the viral infection are not limited to these stressors. Further stressors that can be used alternatively or additionally for the purpose of the invention for virus reactivation are chemical agents, cellular messenger substances, in particular neurotransmitters and neuroindicators, changes in the ion composition of the medium, in particular depolarizing ion changes, pH value change and the reduction of the oxygen partial pressure during cultivation.
Preferably, there is a period of about 24 hours between a first and a second exposure. In particular, the time of the final (for example, second) exposure is in the range of at least 7 hours and in particular up to 25 hours before the conclusion of the cultivation phase, that is, before the fixing of the test tissue. In a special variant, an exposure of the tissue with UVB light (312 nm) with approx. 1500 mJ preferably twice for respectively 6 to 10 min takes place for reactivation. The first exposure takes place in particular 28 to 34 hours before fixing, the second exposure takes place in particular 5 to 9 hours before fixing.
The subject matter of the invention is also a method for finding (screening) an active ingredient with anti-viral action and for the selection thereof from a group of substances to be examined. In a first step, the in vitro test tissue according to the invention is provided with virally infected neuronal cells integrated therein. In a further step, the latent virus infection of the neuronal cells is specifically reactivated.
In a further step, the in vitro test tissue is brought into contact with the substance (potential active ingredient) to be tested for the antiviral property. The bringing into contact takes place in a first variant even before the specific virus reactivation. In an alternative variant, this bringing into contact does not take place until after the specific virus reactivation.
In a further step, the extent of the virus activation is tested, thereby in particular the reduction of the extent of the virus activation after bringing the in vitro test tissue into contact with the substance to be tested compared to the virus activation of a parallel control batch, which was not brought into contact with the substance to be tested, indicates an antiviral effect of the substance. Alternatively, the reduction of the viral load by the substance to be tested can be compared to a control batch, wherein a known active ingredient with an anti-viral action was used as comparison active ingredient. Known active ingredients, for example, virustatics such as aciclovir, can be applied as a control.
In a following step, the substance that can thus be characterized as having an antiviral action is identified and/or selected and provided from the group of the substances to be tested, optionally automatically.
The substance to be tested in a first variant of the invention is applied topically to the in vitro test tissue. Through topical application active substances that can be used in particular therapeutically on the skin surface can be tested or identified in vitro reproducibly and under standardized conditions. In an alternative variant, the substance to be tested is applied into the culture medium surrounding the test tissue.
In one variant, the substance to be tested is brought into contact with the in vitro test tissue following the reactivation of the virus, namely preferably in a period of 2 to 7 days, preferably 2 to 4 days, after the virus reactivation. In an alternative variant, bringing the test tissue into contact with the substance to be tested already takes place before or, alternatively or additionally, in the course of the induction of the reactivation. The addition of the substance can already take place from day 1 of the cultivation phase of the test tissue in the airlift culture.
To verify the extent of the virus activation, the invention provides in a first assay to carry out a quantitative RT-PCR. Specifically virus-relevant gen expressions are thereby tested in a manner known per se. In an alternative assay, an immunohistochemical staining with in particular HSV1 specific antibodies is carried out. In a special embodiment these are polyclonal anti-HSV1 antibodies. The immunohistochemical staining is carried out in a manner known per se and can optionally be quantified in a manner known per se. If the test tissue is thereby cultivated in multiwall plates, for example, the staining can be automatically quantified directly in the test tissue preparation microscopically and/or densitometrically.
The invention is characterized in more detail by the following examples and figures, without these being understood to be restrictive.
BRIEF DESCRIPTION OF DRAWINGS
The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
FIG. 1 : Diagrammatic representation of the structure of the three-dimensional in vitro skin equivalent, composed of an epidermis layer with keratinocytes and a dermis layer with fibroblasts embedded in a collagen biomatrix. Between the epidermis and the dermis a basement membrane forms (fibronektin).
FIG. 2 : Specific embodiment of the method for producing an in vitro test system for testing viral infections and for screening active ingredients: in a first step (1) a neuronal cell line (PC-12) is infected with HSV1; a latent infection develops (2). The latently infected PC-12 cells are integrated into the dermis layer (3), optionally together with immunocompetent Langerhans cells. For the complete buildup of the 3D tissue, after the application of a fibronectin layer, immortalized modified keratinocyte cell line, for example, HaCaT/ΔTLR2/ΔTLR9, are applied to the dermis layer in order to form an epidermis layer (4). Through UVB radiation (312 nm, 1500 mJ, 8 min, for example twice at an interval of 24 hours), the specific virus reactivation takes place in the intePC-12 cells (5). The active virus infection occurring as a result of the reactivation and the starting intercellular communication can be modified by bringing into contact with antiviral active ingredients (6). The viral load in the tissue is then subsequently determined by means of histological staining (7).
FIG. 3 : Histological cross section of an in vitro test system according to the invention (HE staining) with dermis layer (light) and epidermis layer (dark) above it. Primary fibroblasts and PC-12 cells (cluster) are embedded in the dermis layer.
FIG. 4 AB: Antibody-stained cross sections of the skin models according to FIG. 3 for the specific detection of PC-12 cells ( FIG. 4B ) as well as the isotype control ( FIG. 4A ); primary antibody: anti-tyrosine hydroxylase (abcam), dilution 1:400, as well as IgG2a isotype control (Dako), dilution 1:400; secondary antibody: anti-mouse (Dako).
FIG. 5 ABCD: Antibody-stained cross sections of the skin models according to FIG. 3 for the specific detection of HSV1. Before ( FIG. 5A , FIG. 5B and FIG. 5G ) as well as following a UVB exposure twice for activation, namely 55 hours and 29 hours ( FIG. 5C , FIG. 5D and FIG. 5H ) or 31 hours and 7 hours ( FIG. 5E and FIG. 5F ) before the end of the cultivation; primary antibody: polyclonal anti-HSV 1 (Biogenex), dilution 1:300; secondary antibody: anti-mouse (Dako).
Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.
DETAILED DESCRIPTION
Example embodiments will now be described more fully with reference to the accompanying drawings.
Exemplary Embodiment
For the infection of the neuronal PC-12 cell line, the cells are seeded in a depression of a 6-well plate and incubated with the herpes simplex virus strain HF (ATCC, VR260) with a viral load of 1 PFU/cell for two hours at 37° C. Subsequently all virions not absorbed are removed by washing multiple times with buffer (PBS). The cells are cultivated for another 24 hours with fresh medium.
To develop a latent HSV 1 infection, the cells are subcultivated several times (2 to 4 passages). Before the integration into the in vitro test model, a check is carried out that no more virus activity is detectable. To this end, before each passage approx. 1 mm culture supernatant is held back and the degree of infection (TCID50) is determined using a cell-based test assay with Vero (B) cells. With this method of end dilution, the dilution stage of the material to be tested in which an infection takes place is determined. Several dilution stages are hereby prepared in parallel and it is determined at which dilution 50% of the inoculated cell cultures are infected. To detect the latent infection, alternatively the method of in situ hybridization is used. Latency-associated transcripts (LAT) are detected thereby.
The buildup of the in vitro test tissue is carried out according to a protocol optimized for the embedding of the PC 12 cells: fundamentally, the buildup is carried out in two steps. In a first step, the dermal part of the test tissue is built up, wherein primary fibroblasts as well as PC-12 cells latently infected with HSV1 are integrated into a collagen matrix with type 1 collagen. To this end, respectively 0.25×10 6 ml fibroblasts and 0.14×10 6 ml latently infected PC-12 cells are resuspended free from bubbles in a freshly produced solution of collagen I and the suspension is transferred into an insert of a 24-well plate.
In a second step, the layering of the dermis with human keratinocytes (0.4×10 6 per ml) takes place, which then form the epidermal layer. Before the application of the keratinocytes, the dermal collagen matrix is layered with fibronectin, which then forms the basement membrane. As a negative control, a skin equivalent with non-infected PC 12 cells is built up as test tissue.
In a further assay, an immunocomponent, in particular Langerhals cells, is integrated into the test model. In a first assay, before seeding of the keratinocytes the immune cells are seeded on or in the biomatrix, in a further assay thereof, immune cells are seeded on or in the biomatrix during or following the seeding of the keratinocytes.
The buildup of the in vitro test tissue covers a total of about 21 days. The test tissue goes through different cultivation phases during this time. In the first six days, the so-called submerse phase, the tissue is cultivated completely covered with medium. Subsequently, a 14-day to 15-day airlift phase follows, wherein the test assays are carried out on the tissue. After the conclusion of the cultivation phase, the test tissue is fixed in a manner known per se optionally in Bouin's fixative solution or by means of Histofix® and subsequently preferably embedded in paraffin. In a manner known per se tissue sections are produced and a hematoxylin and eosin staining (HE) and additionally or alternatively specific antibody staining are carried out in a manner known per se according to standard protocols.
The results of the embedding of the PC-12 cells are shown in FIGS. 4 and 5 . The embedded PC-12 cells can be shown in the dermis tissue in particular by histological HE staining as well as by specific antibody detection.
The specific virus reactivation is carried out in a period of at least 7 hours up to a maximum of 25 hours before the end of the cultivation phase, that is, the fixing of the tissue. For specific virus reactivation, the tissue is exposed to UVB radiation. Radiation is carried out at a wavelength of 312 nm and an energy equivalent of 1500 mJ respectively for 8 minutes. The radiation is repeated at an interval of approx. 24 hours.
In an alternative assay, the in vitro test tissue is produced with keratinocytes from the HaCaT cell line instead of primary keratinocytes. These HaCaT cells are genetically modified in the form of knock down cell lines: HaCaT/TLR2Δ and HaCaT/TLR9Δ. With the aid of these knock down cell lines, the role of the respective TLR in the scope of an HSV infection can be studied in more detail.
To test antiviral active ingredients, a “time and dose response” analysis is carried out, with the aid of which the concentration-dependent cytotoxicity and the antiherpetic effect of the individual substance can be examined. The application of the substance to be tested is carried out optionally topically in powder form or dissolved in airlift medium from day 0 of the airlift phase. Parallel thereto, a control batch is cultivated analogously with a control substance known to have an anti-viral action (Aciclovir; 50 μmol/l).
The subsequent immunohistochemical staining with an antibody specific for HSV1 shows the viral load in the microscopic investigation. By comparison of the staining in the control batch, an evaluating statement on the effectiveness of the substance concretely studied can be made.
The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.
Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail. Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.
The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.
Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
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The invention relates to a multi-layered biological in vitro tissue containing: dermis layer, containing a collagen biomatrix with fibroblasts embedded therein and epidermis layer, containing epithelial cells. It is provided that latently virally infected neuronal cells are integrated at least into the dermis layer.
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BACKGROUND OF THE INVENTION
The present invention relates to improvements in paper making machines, and more particularly to a twin wire machine of the type capable of making a multi-ply paper web with improved means for controlling the relative running positions of the wires.
In high speed traveling wire paper making machines, the positions of the wire must be controlled so that they do not skew sideways and so that the web remains in a uniform lateral position during continuing operation. Conventionally, this has been done by mounting the supporting bearing at one end of one of the wire support rolls so that the bearing can shift forward or rearward in a machine direction to regulate the running position of the wire. That is, as the end of the roll shifts either toward the oncoming wire or with the direction of the traveling wire, the wire will tend to skew to the left or right depending on how the roll end changes.
With twin wire machines wherein two wires are run together in close running relationship along a forming run, the position of both wires must be controlled. An example of such an installation is in a multi-ply paper web machine wherein the lower wire is a fourdrinier, and a series of upper forming wires are pressed into the fourdrinier at successive locations with an additional layer of web formed at each location. It has been found to involve a relatively complicated and expensive equipment to control the lateral position of the upper looped forming wire by constructing one of the guide rolls so as to be shiftable. Such shiftable roll requires equipment strong enough to support the bearings at each end with the bearing at one end being pivotally mounted and the bearing at the other end being shiftably mounted so as to shift forward or rearwardly in the direction of wire travel.
An important object of the present invention is to provide an improved device which will make it unnecessary to provide a shiftable wire guide roll within the looped forming wire of a twin wire machine.
A further object of the invention is to provide an improved twin wire machine wherein the tracking location of the mating or auxiliary wire of a twin wire machine is controlled by supporting the wire on rotatable rolls fixedly located on a frame and shifting the position of the entire frame relative to the main fourdrinier wire.
A still further object of the invention is to provide an improved method and structure for changing the tracking location of the supporting frame and rolls of a mating wire in a twin wire paper making machine.
Other objects, advantages and features will become more apparent, as well as equivalent structures which are intended to be covered herein, with the teaching of the principles of the present invention in connection with the disclosure of the preferred embodiments thereof in the specification, claims and drawings, in which:
DRAWINGS
FIG. 1 is a somewhat schematic side elevational view of a portion of a twin wire paper making machine constructed and operating in accordance with the principles of the present invention; and
FIG. 2 is a somewhat schematic horizontal sectional view taken substantially along line II--II of FIG. 1.
DESCRIPTION
As illustrated in FIG. 1, the mechanism has a traveling fourdrinier wire 10 which is supported and carried on rolls including a breast roll 9. A couch roll and other wire supporting rolls are provided in the usual manner, and these rolls are omitted from the drawing and their structures and positions will be fully understood by those versed in the art. Positioned above the fourdrinier wire 10 is a headbox 11 with a slice 12 for discharging stock onto the traveling wire. Principally, the slice is provided for the purposes of providing a fibrous paper making stock into the forming zone between the lower fourdrinier wire 10 and an upper looped forming wire 15 with the forming zone extending essentially from location 16 to location 17 through which the wires run in close running adjacent web forming engagement, preferably with the upper wire pressed into the lower wire as illustrated.
The slice is adjustable in position, and the upper slice lip is constructed adjustable by means of a screw jack 13 so as to control the quantity of stock deposited onto the wire.
The arrangement is well adapted to use a machine for making multiple layered webs, and in such operation a first layer will be formed on the wire 10 through the forming zone and at the offrunning side, the web layer will follow the lower wire 10 at the location W to a second station where another fourdrinier will place a second layer of stock on the web and another upper unit having a looped forming wire similar to the one illustrated will be provided for forming the second layer of the web on the first. Additional layers will be formed in accordance with the product to be made.
The headbox is supported on a mill floor F by adjustable legs 14 which are located at the side of the headbox outside of the edges of the fourdrinier wire 10. While the fourdrinier wire 10 may be referred to as the lower wire and the mating wire 15 as the upper wire, it will be understood that this is not to be considered limiting as to their relative locations, and the unit may run in a vertical position or with the positions of the two wires reversed.
The upper wire 15 is supported as a unit on a frame 18 with rotatable rolls 19, 20 and 21 in relatively fixed positions on the frame. The rolls are respectively carried in bearings 22, 23 and 26 with the bearings 22 and 26 fixedly mounted on the frame, and the bearing 23 mounted on a swing arm 24 which is adjustable by a screw jack 25 on a brace 34 so as to tension the looped upper wire 15. The bearings are constructed so that the axis of each of the three rolls are parallel and no means need be provided to skew the axis of any of the rolls for training the wire 15 in the proper lateral cross machine direction on the rolls.
Each of the rolls are provided with a cleaning doctor as illustrated at 31, 32 and 33, and the doctors 31 and 33 can be fixedly mounted on the frame, and the doctor 32 fixedly mounted on the swing arm 24. A wire cleaning water jet 35 is positioned in a convenient location supported by suitable means at its ends.
Along the forming run, the upper wire 15 is provided with blades or foils within to remove water expressed from the stock due to pressure between the wires while it is traveling along the forming run. These foils are shown at 27 and are mounted at suitable supports on the inner surface of the wire 15 and the foils 27 are arranged in a generally arcuate path so that the forming wires extending from foil to foil will follow a general arcuate path through the forming zone. At the end of the forming zone, the wires separate with the web following the fourdrinier wire and the fourdrinier wire is wrapped over a suction box 30 having a curved perforate wire engaging top 29.
The upper frame unit 18 with its rolls 19, 20 and 21 is positioned centered vertically over the fourdrinier wire 10. That is, considering the frame 18 having a central axis which extends in a machine direction down the center of the frame, this center axis will extend parallel to the center of the general plane of the fourdrinier wire 10. By shifting the upper frame 18 with its rolls and supported upper wire 15 so that the axis pivots laterally parallel to the plane of the fourdrinier wire, the upper wire 15 will be caused to track in the proper location on its supporting rolls due to the reactive forces on the upper wire 15 along the forming zone. This avoids the necessity of having to construct one of the supporting rolls, such as 19, 20 or 21, so that its bearing support at its ends are pivotal and avoids the necessity of having to provide operating equipment on the upper frame which controls the pivotal position of such a roll. The rolls will be maintained on parallel axes at all times so that the wire is evenly stretched across its width.
To change the position of the frame 18 for the upper wire 15, it is provided with a base 38 carried on shiftable bearings. The upper frame is mounted on side legs 36 and 37 at the edges of the wire which seat on the base 38. The base itself is pivotally mounted, and preferably the pivot is located at the head end of the base 38 as shown at 42 in FIG. 2. The pivot 42 is shown in a preferred form located at one corner of the base 38 with the other corners supported on flat horizontal slide bearings 39, 40 and 41. These slide bearings may be of various suitable commercial types such as known as a Lubrite bearing, or a bonded Teflon bearing, or a water hydrostatic bearing may be employed. A large bearing is preferred with a very low initial starting resistance so that the upper frame can be shifted rapidly and for very small increments to very accurately maintain the upper wire 15 in position.
To apply power to shift the position of the upper unit, a screw jack 43 is mounted on the floor F with a connecting rod 44 pivotally connected to an arm 45 secured to the base 38. The screw jack 43 is opeated by a mechanism which senses the position of the wire, and this mechanism has a paddle 46 engaging the edge of the wire, FIG. 1. The position of the paddle is sensed by a support 47 which provides an output signal which is transmitted to the screw jack 43. This may be done electrically through connecting wires 48, and various known servo mechanisms may be employed to operate the screw jack responsive to the position of the paddle 46.
It has been discovered that the position of the upper wire 15 can be accurately controlled and is immediately responsive to the changing of the pivotal position of the frame 18. The four point support shown in FIGS. 1 and 2 is a preferred arrangement, but in certain installations, space or other construction requirements may indicate that other forms of support may be employed, and the pivot, for example, can be located at the center of the lead end of the frame 38 or on the trailing end, or at the center of the frame, and the other slidable support bearings arranged so as to permit pivotal shifting of the frame support for the upper wire. The support arrangement makes it possible to shift the axis of the frame supporting the upper wire in a plane parallel to the fourdrinier wire so that the unit is pivoted to the left or right and the upper wire will track accordingly due to the reactive forces between the upper wire and the lower wire in the forming zone.
Thus, it will be seen that I have provided an improved mechanism for the control of the relative positions of the wires in a twin wire machine which meets the objectives and advantages set forth. The arrangement accomplishes a simplified construction eliminating the expense of a pivotal roll and makes it possible to use a support unit for the support wire wherein all the rolls operate on parallel axes. The arrangement automatically accommodates alignment between the upper unit and the lower fourdrinier wire, and initial aligning procedures heretofore necessary are eliminated. A uniform rapid control of wire position is achieved which in turn improves the uniformity and quality of the paper web which is made.
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An apparatus and method for making a paper web with a traveling fourdrinier wire and a looped mating wire pressed into the fourdrinier wire along a forming run and a headbox with a slice for delivering stock at the head end of the forming run, the mating wire being supported on rotatable rolls fixedly carried on a frame with the frame supported for pivotal shifting movement about an axis at right angles to the plane of the fourdrinier wire so that the entire carrying unit for the mating wire is shifted to cause it to track properly.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of the filing date of U.S. provisional patent application No. 60/522,398, filed Sep. 24, 2004, the contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a wireless communications system, and more particularly to a method for discarding data segments in a wireless communications system.
[0004] 2. Description of the Prior Art
[0005] New uses are constantly being found for wireless communications. Initially limited to voice communications, packetized data has opened the field to cellular modems, camera phones, fixed-wireless transceivers for high-speed networking, and myriad other uses. The field is growing rapidly and requires sophisticated protocols to handle the increasing amount of data being transmitted. The Universal Mobile Telecommunications System (UMTS) specified by the 3 rd Generation Partnership Project (3GPP™) is an example of such a new communications protocol. The 3 rd Generation Partnership Project (3GPP) specification, TS 25.322 V6.1.0 (2004-06) Radio Link Control (RLC) protocol specification (referred to hereinafter as 3GPP TS 25.322), included herein by reference, provides a technical description of data transmission control protocols thereof. UMTS utilizes a three-layer approach to communications. The three-layer protocol has a first layer, the physical transport layer; a second layer, where data is packetized, collated, and organized; and a third layer, which interfaces between the second layer and applications generating or using the data.
[0006] The packetization and collation processes are designed to handle missing data segments, due to noise in transmission or other errors, by triggering a retransmission procedure. When a collation cannot be fulfilled by the retransmission procedure due to a protocol error, a reset procedure may be initiated to recover the transmission from the protocol error. The reset procedure can cause large delays as all the state variables are reset and the transmission entity is started over from the beginning. These problems occur primarily in the second (packet control) layers.
[0007] Please refer to FIG. 1 , a block diagram of the three layers in such a communications protocol. In a typical wireless environment, a first station 300 is in wireless communication with one or more second stations 400 . An application 330 on the first station 300 composes a message 310 and has it delivered to the second station 400 by handing the message 310 to a third layer interface 320 . The third layer interface 320 may also generate some third layer signaling messages 320 a for the purpose of controlling third layer operations. The third layer interface 320 delivers either the message 310 or the third layer signaling message 320 a to a second layer interface 360 in the form of second layer service data units (SDUs) 340 . The second layer SDUs 340 may be of any length. The second layer interface 360 composes the SDUs 340 into one or more second layer protocol data unit(s) (PDU) 380 . Each second layer PDU 380 is of a fixed length, and is delivered to a first layer interface 390 . Note that the fact that variable length SDUs are transported in fixed length PDUs generates issues that are highly relevant to the present invention, and these issues are discussed in more detail below. The first layer interface 390 is the physical layer, transmitting data to the second station 400 . The transmitted data is received by the first layer interface 490 of the second station 400 and reconstructed into one or more PDUs 480 , which is/are passed up to the second layer interface 460 . The second layer interface 460 receives the PDU(s) 480 and builds up one or more second layer SDU(s) 440 from the PDU(s) 480 . The second layer SDU(s) 440 is/are passed up to the third layer interface 420 . The third layer interface 420 , in turn, converts the second layer SDU(s) 440 back into either a message 410 , which should be identical to the original message 310 that was generated by the application 330 on the first station 300 , or a third layer signaling message 420 a , which should be identical to the original signaling message 320 a generated by the third layer interface 320 , and which is then processed by the third layer interface 420 . The received message 410 is passed up to an application 430 on the second station 400 .
[0008] In order to detect missing data, the protocol relies on the collation of PDUs in the second station's 400 second layer 420 to notice that a PDU has not been received and to send a request for retransmission through the first layer 490 to the first layer 390 of the first station 300 .
[0009] Please refer to FIG. 5 , which illustrates a typical sequence of PDUs containing SDUs. In this example, two SDUs, SDU 1 and SDU 2 , each of length 80 octets, are packetized into four PDUs P 0 , P 1 , P 2 , P 3 each of length 64 octets. Each PDU contains a header, respectively P 0 h , P 1 h , P 2 h , P 3 h , which is two octets long, leaving 62 octets for the contents of the PDUs. Each header contains, among other data, a sequence number (SN), which increases sequentially in each PDU transmitted, and a flag indicating whether or not the PDU has a length indicator (LI), which indicates the position of the last byte of data of a SDU. The flag is located at the last bit of the header. If the flag is set to 1, then the PDU contains a LI structure of one octet, with the first seven bits indicating the length of the data to which it refers and the eighth bit being a flag indicating whether this is the last LI in the PDU. PDU P 0 has the SN of zero (0), and the flag indicates that there is no LI. The data 10 a is thus entirely from a single SDU. PDU P 1 has SN equal to 1, and its flag set to 1 indicates that the next octet is a LI structure, which contains a LI field and a one-bit flag. The first LI field 10 L has a value of eighteen (18) followed by a flag indicating another LI structure to follow; PDU P 1 then has a second LI field P 1 p L with a value of 127 (all 1's for the 7 bits of the second LI) followed by a flag set to 0 indicating that the second LI is the last LI in the PDU. The first eighteen data bytes of this PDU, following the two LI structures, are the remainder of the data 10 b for SDU 1 . The special value (127) of the second LI indicates that the rest part of the PDU P 1 p is a padding, which is padded with arbitrary value to keep the length of the PDU P 1 fixed and shall be neglected. PDU P 2 has the SN of 2, and the flag indicates that there is no LI. The data 12 a is thus entirely for a single SDU. Similarly, PDU P 3 has SN of 3, and its flag set to 1 indicates that it contains a LI structure. The LI 12 L has a value of 18 and a flag indicating a second LI structure follows; PDU P 3 then has an LI field P 3 p L with a value of 127 followed by a flag set to 0. Thus, the first eighteen data bytes of this PDU 12 b , following the two LI structures, are the remainder of the data 10 b for SDU 2 . The rest part P 3 p is padding.
[0010] Please refer to FIG. 6 , which illustrates another typical sequence of PDUs containing SDUs. In this example, two SDUs, SDU 1 and SDU 2 , each of length 80 octets are packetized into three PDUs Q 0 , Q 1 , Q 2 each of length 64 octets. Each PDU contains a header, respectively Q 0 h , Q 1 h , Q 2 h , Q 3 h , which is two octets long, leaving 62 octets for the contents of the PDUs. PDU Q 0 has the SN of zero (0), and the flag indicates that there is no LI. The data 14 a is thus entirely from a single SDU SDU 1 . PDU Q 1 has a header Q 1 h with SN equal to 1 and its flag set to 1 indicating that a LI structure follows the header Q 1 h . The LI field 14 L has a value of 18 followed by a flag set to 0 indicating no more LIs; the first eighteen data octets 14 b of this PDU are thus the remainder of SDU 1 , and the remaining forty-three data octets 16 a are from the next SDU, SDU 2 . PDU Q 2 has a header Q 2 h with SN equal to 2 and its flag set to 1 indicating that a LI structure follows the header Q 2 h . The Li field 16 L has a value of 37 followed by a flag set to 1 indicating another LI follows. The second LI has a value of 127 followed by a flag set to 0 indicating no more LIs. The first thirty-seven data octets 16 b of the PDU are the remainder of SDU 2 , and the remaining octets are padding Q 2 p to be neglected.
[0011] Please refer to FIG. 7 , which illustrates a third typical sequence of PDUs containing SDUs. In this example, two SDUs, SDU 1 of length 62 octets and SDU 2 of length 80 octets, are packetized into four PDUs R 0 , R 1 , R 2 and R 3 , each of length 64 octets. Each PDU contains a header, respectively R 0 h, R 1 h , R 2 h , R 3 h , which is two octets long, leaving 62 octets for the contents of the PDU. PDU R 0 has the SN of zero (0), and the flag indicates that there is no LI. The data 18 a is thus entirely from a single SDU. PDU R 1 has SN equal to 1, and its flag set to 1 indicates that it contains a LI structure. The LI 18 L has a value of zero (0) followed by a flag set to 1 indicating another LI to follow; it then has an LI field R 1 p L with a value of 127 followed by a flag set to 0 indicating that it is the last LI in the PDU. The special value (0) of the first LI indicates that the previous PDU R 0 was exactly filled with the last segment of a SDU, SDU 1 , and there is no LI field that indicates the end of the SDU in the previous PDU R 0 . Thus, the rest part R 1 p of PDU R 1 is a padding part to be neglected. PDU R 2 has the SN of 2, and the flag indicates that there is no LI. The data 20 a is thus entirely from a single SDU, SDU 2 . PDU R 3 has a header R 3 h with SN of 3 and its flag set to 1 indicating that a LI structure follows the header R 2 h . The LI field 20 L has a value of 18 followed by a flag set to 1 indicating another LI to follow; it then has an LI field R 3 p l with a value of 127 followed by a flag set to 0 indicating that there are no further LI fields. Thus, the first eighteen data bytes of this PDU, following the two LI structures, are the remainder of the data 20 b for SDU 2 . The remaining part R 3 p of this PDU is padding to be neglected.
[0012] In the prior art, the method for discarding an SDU is as follows. Please refer to FIG. 2 , FIG. 3 , and FIG. 4 , which are flowcharts of the prior art method of discarding SDUs. These steps are explained below:
[0013] Step 100 : Trigger a new Move Receiving Window (MRW) procedure. The sender indicates that at least one SDU is to be discarded.
[0014] Step 102 : Set up a STATUS PDU with a MRW superfield (SUFI). Create a PDU structure and populate its basic fields.
[0015] Step 104 : Determine whether “send MRW” is configured for this RLC entity. When true, proceed to step 110 . When not true, proceed to step 106 .
[0016] Step 106 : Set the STATUS PDU to include the last SN_MRW i field for the last discarded SDU.
[0017] Step 108 : Optionally set the STATUS PDU to include other SN_MRW i fields for other discarded SDUs, and proceed to step 116 (marked by “A”, in FIG. 3 ).
[0018] Step 110 : Check whether there are more than 15 discarded SDUs, which is the largest number of SDU SN_MRW i fields that can fit in the STATUS PDU. When more than fifteen SDUs are being discarded, proceed to step 112 . When fifteen or fewer SDUs are being discarded, proceed to step 114 .
[0019] Step 112 : Set up the MRW SUFI for the first fifteen discarded SDUs.
[0020] Step 114 : Include one SN_MRW i field for each corresponding discarded SDU. Proceed to step 116 (marked by “A”, in FIG. 3 ).
[0021] Step 116 : Check whether the last discarded SDU ends in a PDU which contains the LI of the last discarded SDU and contains no new SDUs. When true, proceed to step 118 . When false, proceed to step 120 .
[0022] Step 118 : Set the last SN_MRW i field (SN_MRW LENGTH ) to be the sum of one plus the SN of the PDU at which the last discarded SDU ends, and set N LENGTH to zero. Proceed to step 122 (marked by “B” in FIG. 4 ).
[0023] Step 120 : Set the last SN_MRW i field (SN_MRW LENGTH ) to be the SN of the PDU which contains the LI of the last discarded SDU, and set N LENGTH to be the number of LIs corresponding to discarded SDUs within the PDU which contains the LI of the last discarded SDU. Proceed to step 122 (marked by “B” in FIG. 4 ).
[0024] Step 122 : Set each of the other SN_MRW i fields to be the SN of the AMD PDU containing the LI of the corresponding discarded SDU
[0025] Step 124 : Check whether there is only one SN_MRW i field and if its corresponding discarded SDU extends above the configured transmission window. When true, proceed to step 126 . When false, proceed to step 128 .
[0026] Step 126 : Set LENGTH to zero, and proceed to step 130 .
[0027] Step 128 : Set LENGTH to the number of SN_MRW i fields, and proceed to step 130 .
[0028] Step 130 : Submit the STATUS PDU with MRW SUF 1 for transmission.
[0029] Step 132 : Finish (exit procedure).
[0030] please refer to FIG. 5 with regard to the above steps, as well as FIG. 2 , FIG. 3 , and FIG. 4 . When an SDU discard procedure is initiated to discard SDU 1 , a MRW procedure is triggered at step 100 (shown in FIG. 2 ). The method sets up a STATUS PDU with MRW SUF 1 in step 102 . Since only one SDU is being discarded, the method will produce the same results whether step 104 chooses to go to step 106 or step 110 . When “Send MRW” is not configured, step 1 06 includes the SN_MRW 1 field in the MRW SUFI for SDU 1 , and step 108 is ignored since there are no more SDUs being discarded. When “Send MRW” is configured, step 110 proceeds to step 114 since only one SDU is being discarded, and step 114 includes the SN_MRW 1 field in the MRW SUFI for SDU 1 . Both paths then converge again at step 116 (shown in FIG. 3 ). In step 116 , the last discarded SDU, SDU 1 , ends in PDU P 1 , and PDU P 1 contains the LI 10 L, and contains no new SDUs after SDU 1 since its remainder is filled with padding P 1 p . Therefore, the method proceeds to step 118 , where the last SN_MRW i field, SN_MRW LENGTH , is set to the sum of one plus the SN of PDU P 1 , or the value 2, since PDU P 1 has an SN of 1. The method then proceeds to step 122 (shown in FIG. 4 ), where since there are no more discarded SDUs, nothing is done. At step 124 , depending on the actual position of the transmission window, the method either goes to step 126 or step 128 , where the LENGTH field of the MRW SUFI is filled in with either the value 0 or the value 1 respectively. Finally, at step 130 , the method is ready to transmit the just-created STATUS PDU with MRW SUFI, and the method finishes at step 132 .
[0031] Next, please refer to FIG. 6 with regard to the above steps, as well as FIG. 2 , FIG. 3 , and FIG. 4 . When an SDU discard procedure is initiated to discard SDU 1 , a MRW procedure is triggered at step 100 (shown in FIG. 2 ). The method sets up a STATUS PDU with MRW SUFI in step 102 . Since only one SDU is being discarded, the method will produce the same results whether step 104 chooses to go to step 106 or step 110 . When “Send MRW” is not configured, step 106 includes the SN_MRW 1 field in the MRW SUFI for SDU 1 , and step 108 is ignored since there are no more SDUs being discarded. When “Send MRW” is configured, step 110 proceeds to step 114 since only one SDU is being discarded, and step 114 includes the SN_MRW 1 field in the MRW SUFI for SDU 1 . Both paths then converge again at step 116 (shown in FIG. 3 ). In step 116 , the last discarded SDU, SDU 1 , ends in PDU Q 1 , and PDU Q 1 contains the LI 14 L, and contains a new SDU, SDU 2 , which has its first data segment 16 a . Therefore, the method proceeds to step 120 , where the last SN_MRW i field, SN_MRW LENGTH , is set to the SN of PDU Q 1 , or the value 1, since PDU Q 1 has an SN of 1. The method then proceeds to step 122 (shown in FIG. 4 ), where since there are no more discarded SDUs, nothing is done. At step 124 , depending on the actual position of the transmission window, the method either goes to step 126 or step 128 , where the LENGTH field of the MRW SUFI is filled in with either the value 0 or the value 1 respectively. Finally, at step 130 , the method is ready to transmit the just-created STATUS PDU with MRW SUFI, and the method finishes at step 132 .
[0032] For a third example, please refer to FIG. 7 with regard to the above steps, as well as FIG. 2 , FIG. 3 , and FIG. 4 . When an SDU discard procedure is initiated to discard SDU 1 , a MRW procedure is triggered at step 100 (shown in FIG. 2 ). The method sets up a STATUS PDU with MRW SUFI in step 102 . Since only one SDU is being discarded, the method will produce the same results whether step 104 chooses to go to step 106 or step 110 . When “Send MRW” is not configured, step 106 includes the SN_MRW 1 field in the MRW SUFI for SDU 1 , and step 108 is ignored since there are no more SDUs being discarded. When “Send MRW” is configured, step 110 proceeds to step 114 since only one SDU is being discarded, and step 114 includes the SN_MRW 1 field in the MRW SUFI for SDU 1 . Both paths then converge again at step 116 (shown in FIG. 3 ). In step 116 , the last discarded SDU, SDU 1 , ends in PDU R 0 , which does not contains the LI 18 L of the last discarded SDU, SDU 1 . Therefore, the method proceeds to step 120 , where the last SN_MRW i field, SN_MRW LENGTH , is set to the SN of PDU R 1 which contains the LI 18 L of the last discarded SDU, SDU 1 , or the value 1, since PDU R 1 has an SN of 1. The method then proceeds to step 122 (shown in FIG. 4 ), where since there are no more discarded SDUs, nothing is done. At step 124 , depending on the actual position of the transmission window, the method either goes to step 126 or step 128 , where the LENGTH field of the MRW SUFI is filled in with either the value 0 or the value 1 respectively. Finally, at step 130 , the method is ready to transmit the just-created STATUS PDU with MRW SUFI, and the method finishes at step 132 .
[0033] The current method therefore incorrectly sets the MRW SUFI to discard PDU R 0 only, moving the receiving window to start at PDU R 1 . The receiving station or the second station 400 in FIG. 1 will wait to receive PDU R 1 , which is discarded in the transmitting station or the first station 300 in FIG. 1 . A reset procedure will be initiated later.
[0034] As seen in the third example, a key problem of this method is that it sometimes fails to discard a PDU when it should. This causes a reset procedure to be triggered occasionally in the normal course of discarding SDUs. As these reset procedures waste potentially large amounts of bandwidth, an improved method for discarding SDUs is clearly necessary.
SUMMARY OF THE INVENTION
[0035] It is therefore a primary objective of the claimed invention to provide a method for handling an SDU discard procedure to eliminate the risk of unnecessary reset procedures due to erroneous SDU discard procedure.
[0036] Briefly summarized, the claimed invention is a method for handling discarding of a sequence of service data units in a communications system, the sequence of service data units comprising at least a last discarded service data unit (SDU), the method comprising the following steps: when a protocol data unit (PDU) containing a length indicator of the last discarded SDU contains no new SDUs: creating a move receiving window super field (MRW SUFI), setting a N LENGTH field of the MRW SUFI to 0, setting a last sequence number move receiving window field (SN_MRW LENGTH ) to a sum of one plus a sequence number (SN) of the PDU containing the length indicator of the last discarded SDU, and issuing the MRW SUFI.
[0037] These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0038] FIG. 1 is a diagram showing an overview of the layers and communications between a first station and a second station.
[0039] FIG. 2 is a flowchart of a prior-art SDU discard method.
[0040] FIG. 3 is a flowchart of a prior-art SDU discard method.
[0041] FIG. 4 is a flowchart of a prior-art SDU discard method.
[0042] FIG. 5 is a data block diagram showing a typical segmentation of SDUs where no concatenation is used.
[0043] FIG. 6 is a data block diagram showing a typical segmentation of SDUs where concatenation of SDU segments is used.
[0044] FIG. 7 is a data block diagram showing a second typical segmentation of SDUs where no concatenation of SDU segments is used.
[0045] FIG. 8 is a flowchart of the enhanced SDU discard method.
DETAILED DESCRIPTION
[0046] Please refer to FIG. 2 , FIG. 8 , and FIG. 4 , which are flowcharts showing the method of the present invention ( FIG. 8 ) in combination with portions of the method of the prior art ( FIG. 2 and FIG. 4 ). Please note that prior art steps 116 and 118 are replaced herein with steps 216 and 218 .
[0047] Step 100 : Trigger a new Move Receiving Window (MRW) procedure. The sender indicates that at least one SDU is to be discarded.
[0048] Step 102 : Set up a STATUS PDU with a MRW superfield (SUFI). Create a PDU structure and populate its basic fields.
[0049] Step 104 : Determine whether “send MRW” is configured for this RLC entity. When true, proceed to step 110 . When not true, proceed to step 106 .
[0050] Step 106 : Set the STATUS PDU to include the last SN_MRW i field for the last discarded SDU.
[0051] Step 108 : Optionally set the STATUS PDU to include other SN_MRW i fields for the other discarded SDUs, and proceed to step 216 (marked by “A”, in FIG. 8 ).
[0052] Step 110 : Check whether there are more than 15 discarded SDUs, which is the largest number of SDU SN_MRW i fields that can fit in the STATUS PDU. When more than fifteen SDUs are being discarded, proceed to step 112 . When fifteen or fewer SDUs are being discarded, proceed to step 114 .
[0053] Step 112 : Set up the MRW SUFI for the first fifteen discarded SDUs.
[0054] Step 114 : Include one SN_MRW i field for each corresponding discarded SDU. Proceed to step 216 (marked by “A”, in FIG. 8 ).
[0055] Step 116 : Check whether the PDU containing the LI of the last discarded SDU contains no new SDUs. When true, proceed to step 218 . When false, proceed to step 120 .
[0056] Step 118 : Set the last SN_MRW i field (SN_MRW LENGTH ) to be the sum of one plus the SN of the PDU which contains the LI of the last discarded SDU, and set N LENGTH to zero. Proceed to step 122 (marked by “B” in FIG. 4 ).
[0057] Step 120 : Set the last SN_MRW i field (SN_MRW LENGTH ) to be the SN of the PDU which contains the LI of the last discarded SDU, and set N LENGTH to be the number of LIs corresponding to discarded SDUs within the PDU which contains the LI of the last discarded SDU. Proceed to step 122 (marked by “B” in FIG. 4 ).
[0058] Step 122 : Set each of the other SN_MRW i fields to be the SN of the AMD PDU containing the LI of the corresponding discarded SDU
[0059] Step 124 : Check whether there is only one SN_MRW i field and if its corresponding discarded SDU extends above the configured transmission window. When true, proceed to step 126 . When false, proceed to step 128 .
[0060] Step 126 : Set LENGTH to zero, and proceed to step 130 .
[0061] Step 128 : Set LENGTH to the number of SN_MRW i fields, and proceed to step 130 .
[0062] Step 130 : Submit the STATUS PDU with MRW SUFI for transmission.
[0063] Step 132 : Finish (exit procedure).
[0064] Please refer to FIG. 5 with regard to the above steps, as well as FIG. 2 , FIG. 8 , and FIG. 4 . When an SDU discard procedure is initiated to discard SDU 1 , a MRW procedure is triggered at step 100 (shown in FIG. 2 ). The method sets up a STATUS PDU with MRW SUFI in step 102 . Since only one SDU is being discarded, the method will produce the same results whether step 104 chooses to go to step 106 or step 110 . When “Send MRW” is not configured, step 106 includes the SN_MRW1 field in the MRW SUFI for SDU 1 , and step 108 is ignored since there are no more SDUs being discarded. When “Send MRW” is configured, step 110 proceeds to step 114 since only one SDU is being discarded, and step 114 includes the SN_MRW1 field in the MRW SUFI for SDU 1 . Both paths then converge again at step 216 (shown in FIG. 8 ). In step 216 , PDU P 1 contains the LI 10 L of the last discarded SDU, SDU 1 , and contains no new SDUs after SDU 1 since its remainder is filled with padding P 1 p . Therefore, the method proceeds to step 218 , where the last SN_MRW i field, SN_MRW LENGTH , is set to the sum of one plus the SN of PDU P 1 , or the value 2, since PDU P 1 has an SN of 1. The method then proceeds to step 122 (shown in FIG. 4 ), where since there are no more discarded SDUs, nothing is done. At step 124 , depending on the actual position of the transmission window, the method either goes to step 126 or step 128 , where the LENGTH field of the MRW SUFI is filled in with either the value 0 or the value 1 respectively. Finally, at step 130 , the method is ready to transmit the just-created STATUS PDU with MRW SUFI, and the method finishes at step 132 .
[0065] Next, please refer to FIG. 6 with regard to the above steps, as well as FIG. 2 , FIG. 8 , and FIG. 4 . When an SDU discard procedure is initiated to discard SDU 1 , a MRW procedure is triggered at step 100 (shown in FIG. 2 ). The method sets up a STATUS PDU with MRW SUFI in step 102 . Since only one SDU is being discarded, the method will produce the same results whether step 104 chooses to go to step 106 or step 110 . When “Send MRW” is not configured, step 106 includes the SN_MRW1 field in the MRW SUFI for SDU 1 , and step 108 is ignored since there are no more SDUs being discarded. When “Send MRW” is configured, step 110 proceeds to step 114 since only one SDU is being discarded, and step 114 includes the SN_MRW1 field in the MRW SUFI for SDU 1 . Both paths then converge again at step 216 (shown in FIG. 8 ). In step 216 , PDU Q 1 contains the LI 14 L of the last discarded SDU, SDU 1 , and contains a new SDU, SDU 2 , which has its first data segment 16 a . Therefore, the method proceeds to step 120 , where the last SN_MRW i field, SN_MRW LENGTH , is set to the SN of PDU Q 1 , or the value 1, since PDU Q 1 has an SN of 1. The method then proceeds to step 122 (shown in FIG. 4 ), where since there are no more discarded SDUs, nothing is done. At step 124 , depending on the actual position of the transmission window, the method either goes to step 126 or step 128 , where the LENGTH field of the MRW SUFI is filled in with either the value 0 or the value 1 respectively. Finally, at step 130 , the method is ready to transmit the just-created STATUS PDU with MRW SUFI, and the method finishes at step 132 .
[0066] For a third example, please refer to FIG. 7 with regard to the above steps, as well as FIG. 2 , FIG. 8 , and FIG. 4 . When an SDU discard procedure is initiated to discard SDU 1 , a MRW procedure is triggered at step 100 (shown in FIG. 2 ). The method sets up a STATUS PDU with MRW SUFI in step 102 . Since only one SDU is being discarded, the method will produce the same results whether step 104 chooses to go to step 106 or step 110 . When “Send MRW” is not configured, step 106 includes the SN_MRW 1 field in the MRW SUFI for SDU 1 , and step 108 is ignored since there are no more SDUs being discarded. When “Send MRW” is configured, step 110 proceeds to step 114 since only one SDU is being discarded, and step 114 includes the SN_MRW 1 field in the MRW SUFI for SDU 1 . Both paths then converge again at step 216 (shown in FIG. 8 ). In step 216 , PDU R 1 contains the LI 18 L of the last discarded SDU, SDU 1 , and contains no new SDUs after SDU 1 since its remainder is filled with padding R 1 p . Therefore, the method proceeds to step 218 , where the last SN_MRW i field, SN —MRW LENGTH , is set to the sum of one plus the SN of PDU R 1 (which contains the LI of SDU 1 ), or the value 2, since PDU R 1 has an SN of 1. Note that the value SN_MRW LENGTH is set to 1 in this scenario by the prior art. The method then proceeds to step 122 (shown in FIG. 4 ), where since there are no more discarded SDUs, nothing is done. At step 124 , depending on the actual position of the transmission window, the method either goes to step 126 or step 128 , where the LENGTH field of the MRW SUFI is filled in with either the value 0 or the value 1 respectively. Finally, at step 130 , the method is ready to transmit the just-created STATUS PDU with MRW SUFI, and the method finishes at step 132 .
[0067] This improved method therefore behaves correctly in all cases when discarding SDUs, including the case where the last segment of a SDU ends within a given PDU but the LI for the SDU is in the next PDU, as well as the more common case where the last segment of a SDU ends in the same PDU as the LI for said SDU. In the example shown in FIG. 7 , the improved method correctly sets the MRW SUFI to discard PDUs R 0 and R 1 , moving the receiving window to start at PDU R 2 . In contrast, the prior art incorrectly moves the receiving window to start at PDU R 1 , thereby initiating a reset procedure later. Thus, the present invention avoids an unnecessary reset procedure and bandwidth is saved.
[0068] Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.
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A method for handling discarding of a sequence of service data units in a communications system is disclosed. The sequence of service data units includes at least a last discarded service data unit (SDU). When a protocol data unit (PDU) containing a length indicator of the last discarded SDU contains no new SDUs, the method includes creating a move receiving window super field (MRW SUFI), setting a N LENGTH field of the MRW SUFI to 0, setting a last sequence number move receiving window field (SN_MRW LENGTH ) to a sum of one plus a sequence number (SN) of the PDU containing the length indicator of the last discarded SDU, and issuing the MRW SUFI.
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CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
Japan Priority Application 2004-301043, filed Oct. 15, 2004 including the specification, drawings, claims and abstract, is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
The present invention relates to plants imparted with transgene-dependent incompatibility upon ZPT2-10 gene introduction; agents and cells for producing the plants; and methods for producing the plants.
BACKGROUND OF THE INVENTION
In practical utilization of transgenic crops, there is concern that their recombinant genes may spread into the environment as a result of mating between wild-type and native species due to pollen dispersion. For example, crossing between herbicide-resistant transgenic crops and weeds may result in “superweeds”, which acquire herbicide resistance and become irresponsive to pesticides (Dale, P. J. et al., Nat. Biotechnol. 20(6) 2002, 567-574). This problem is considered one of the critical problems that need to be solved for promoting public acceptance of transgenic plants from the standpoint of transgenic plant development and production. One of these strategies is utilization of male sterility, which has many examples (Mariani, C. et al., Nature 347, 1990, 737-741) including methods developed by the present applicant (Japanese Patent Application Kokai Publication No. (JP-A) 2001-145429 (unexamined, published Japanese patent application), JP-A 2001-145430, JP-A 2003-92936, and JP-A 2003-92937). However, it is difficult to apply male sterility methods to self-propagating crops, and there are problems such as inevitable mating by cross-pollination. In recent years, there are studies on methods for preventing the spreading of recombinant genes from pollens into the environment by incorporating recombinant genes into chloroplast genomes, which are thought to propagate only through maternal inheritance and not to be inherited via pollens.
SUMMARY OF THE INVENTION
The present invention was achieved in view of the above conditions. An objective of the present invention is to improve plant crossing properties for effectively preventing recombinant genes in transgenic plants from spreading into the environment. Specifically, an objective of the present invention is to provide plants that have acquired transgene-dependent incompatibility through genetic improvement, agents and cells for producing the plants, and methods for producing the plants.
In order to solve the aforementioned problems, the present inventors fused a potato-derived SK2 chitinase gene promoter with the TFIIIA-type zinc-finger transcription factor gene ZPT2-10, which is specifically expressed in the transmitting tissues of the Petunia hybrida style and introduced the SK2:ZPT2-10 into a petunia . The result showed that some of the resulting transformants [transgene-dependent incompatibility (TDI) strain] exhibit useful crossing properties.
The TDI-strain petunia is fertile and produces normal seeds if self propagated or mated with another transformant that comprises the same recombinant gene, and is however infertile when mated with a transformant strain that does not have a TDI property, or with a wild-type plant. That is, the TDI-strain petunia has transgene-dependent incompatibility. The crossing property of TDI strain transformants was observed in both cases where the TDI strain is used as a pollen parent or a pistil parent. Progenies inherit this phenotype along with the introduced SK2:ZPT2-10 gene; and when SK2:ZPT2-10 is lost by segregation, the normal crossing property recovers, thereby making the relation clear between the introduced gene SK2:ZPT2-10 and the phenotype.
The present invention is based on such unprecedented transgene-dependent incompatibility. More specifically, the present invention provides [1] to [6] as follows:
[1]an agent for imparting transgene-dependent incompatibility to a plant, wherein the agent comprises a DNA of any one of (a) to (d) or a vector comprising the DNA as an active ingredient: (a) a DNA encoding a protein comprising the amino acid sequence of SEQ ID NO: 2; (b) a DNA comprising the coding region of the nucleotide sequence of SEQ ID NO: 1; (c) a DNA encoding a protein comprising an amino acid sequence with one or more amino acid substitutions, deletions, additions, and/or insertions in the amino acid sequence of SEQ ID NO: 2; and (d) a DNA which hybridizes under stringent conditions to a polynucleotide comprising the nucleotide sequence of SEQ ID NO: 1; [2] a plant cell capable of regenerating into a plant with transgene-dependent incompatibility, wherein a DNA of any one of (a) to (d) or a vector comprising the DNA is introduced into the cell: (a) a DNA encoding a protein comprising the amino acid sequence of SEQ ID NO: 2; (b) a DNA comprising the coding region of the nucleotide sequence of SEQ ID NO: 1; (c) a DNA encoding a protein comprising an amino acid sequence with one or more amino acid substitutions, deletions, additions, and/or insertions in the amino acid sequence of SEQ ID NO: 2; and (d) a DNA which hybridizes under stringent conditions to a polynucleotide comprising the nucleotide sequence of SEQ ID NO: 1; [3] a plant with transgene-dependent incompatibility regenerated from the plant cell of [2]; [4] a plant with transgene-dependent incompatibility, which is a progeny or a clone of the plant of [3]; [5] a propagating material of the plant of [3] or [4]; and [6] a method for producing a plant with transgene-dependent incompatibility, wherein the method comprises the steps of: (i) introducing a DNA of any one of (a) to (d) or a vector comprising the DNA into a plant cell: (a) a DNA encoding a protein comprising the amino acid sequence of SEQ ID NO: 2; (b) a DNA comprising the coding region of the nucleotide sequence of SEQ ID NO: 1; (c) a DNA encoding a protein comprising an amino acid sequence with one or more amino acid substitutions, deletions, additions, and/or insertions in the amino acid sequence of SEQ ID NO: 2; and (d) a DNA which hybridizes under stringent conditions to a polynucleotide comprising the nucleotide sequence of SEQ ID NO: 1; and (ii) regenerating a plant from the plant cell into which the DNA or the vector is introduced in step (i).
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the SK2:ZPT2-10 gene construct.
FIG. 2 is a set of photographs showing the TDI strain crossing property of a T0 generation. The fruition states in plants resulted from fertile mating ( FIG. 2A ) and infertile mating ( FIG. 2B ) are shown respectively.
FIG. 3 is a photograph of the analysis of transgene inheritance in the T1 generation of a TDI strain. The genomic DNAs of T1 plants resulted from mating TDI-2 with TDI-3 were excised with HindIII, subjected to Southern hybridization using the ZPT2-10 cDNA as a probe, and examined for the presence of the SK2:ZPT2-10 transgene.
FIG. 4 is a photograph showing that the TDI infertility is caused by embryogenesis arrest. In infertile mating (TDI (female)×WT (male)), embryogenesis is arrested between a spherical-shaped embryo and a heart-shaped embryo.
DETAILED DESCRIPTION OF THE INVENTION
ZPT2-10 to provide agents that impart transgene-dependent incompatibility to plants.
In the present invention, the term “transgene-dependent incompatibility” refers to a crossing property that results in fertile plants producing normal seeds when self propagated or mated with a particular transformant comprising the same recombinant gene, and infertile plants when mated with a transformant strain that has no similar properties or with a wild-type plant.
Whether or not an agent comprising a certain gene imparts transgene-dependent incompatibility to a plant can be assessed as shown in Example 3. Specifically, whether a plant has the crossing property can be determined by examining whether a plant, to which a gene comprised in an agent is introduced, produces normal seeds when self-pollination occurs; and whether it fails to reach fruition when pollination occurs through mating with a wild-type strain.
In the present invention, the DNA comprised in an agent that imparts transgene-dependent incompatibility to plants is not particularly limited, and may be in the form of a cDNA or genomic DNA. Genomic DNAs and cDNAs can be prepared by using conventional means known to one skilled in the art. For example, the genomic DNA of ZPT2-10 can be prepared by designing an appropriate primer pair from the known nucleotide sequence (SEQ ID NO: 1) of ZPT2-10, performing PCR using genomic DNA prepared from a plant of interest as template, and screening genomic libraries using the resulting amplified DNA fragment as probe. Similarly, a cDNA encoding ZPT2-10 can be prepared by designing a primer pair as described above, performing PCR using cDNAs or mRNAs prepared from a plant of interest as template, and screening cDNA libraries using the resulting amplified DNA fragment as probe. The DNAs of interest may also be synthesized using a commercially available DNA synthesizer.
As active ingredients of the agents of the present invention, not only the DNAs that encode the petunia -derived ZPT2-10 protein (SEQ ID NO: 2), but also DNAs encoding proteins that are structurally similar to the protein (e.g., mutants, derivatives, alleles, variants, and homologs) can be used as long as they have the function of imparting transgene-dependent incompatibility to plants. Such DNAs include, for example, DNAs encoding a protein comprising an amino acid sequence with one or more amino acid substitutions, deletions, additions, and/or insertions in the amino acid sequence of SEQ ID NO: 2.
Examples of methods well-known in the art for preparing DNAs encoding a protein with altered amino acid sequence include site-directed mutagenesis methods (Kramer, W. and Fritz. H. J., Methods Enzymol. 154, 1987, 350-367). In nature, mutations in nucleotide sequences may also lead to mutations in the amino acid sequences of proteins encoded thereby. As described above, DNAs encoding a protein comprising an amino acid sequence with one or more amino acid substitutions, deletions, or additions in the amino acid sequence of the naturally-occurring ZPT2-10 protein (SEQ ID NO: 2) are included in the DNAs of the present invention, as long as they have the function of imparting transgene-dependent incompatibility to plants.
The number of amino acids to be altered is not particularly limited, but is generally 50 or less, preferably 30 or less, more preferably 10 or less (e.g., 5 or less, or 3 or less). Alterations of amino acids are preferably conservative substitutions. The hydropathic indices (Kyte, J. and Doolittle, R. F., J Mol. Biol. 157(1), 1982,105-132) and hydrophilicity values (U.S. Pat. No. 4,554,101) for each amino acid before and after an alteration are preferably within ±2, more preferably within ±2, and most preferably within ±0.5.
In addition, mutations in a nucleotide sequence are not always accompanied by mutations in the amino acids of the protein (i.e., degenerate mutations). Such degenerate mutants are also included in DNAs as active ingredients of the agents of the present invention.
DNAs encoding proteins that are structurally similar to the petunia -derived ZPT2-10 protein (SEQ ID NO: 2) can be prepared by using hybridization techniques (Southern, E. M., J Mol. Biol. 98(3), 1975, 503-517) and polymerase chain reaction (PCR) (Saiki, R. K. et al., Science 230, 1985, 1350-1354; and Saiki, R. K. et al., Science 239, 1988, 487-491). That is, DNAs of the present invention include DNAs that hybridize under stringent conditions to the DNA consisting of the nucleotide sequence of SEQ ID NO: 1. For isolating such DNAs, hybridization reactions are preferably performed under conditions of stringency. In the present invention, the term “stringent conditions” refers to the conditions of 6 M urea, 0.4% SDS, and 0.5×SSC, and hybridization conditions of equivalent stringency, without being limited thereto. Conditions of higher stringency such as 6 M urea, 0.4% SDS, and 0.1×SSC can be expected to isolate DNAs of higher homologies. A variety of factors such as temperature and salt concentration are considered factors that affect hybridization stringency. One skilled in the art can establish optimal stringencies by appropriately selecting these factors.
The DNAs isolated by the above-described hybridizations at the amino acid level are considered to have a high homology with the amino acid sequence of the petunia -derived ZPT2-10 protein (SEQ ID NO: 2). The term “high homology” refers to identities of at least 50% or more, more preferably 70% or more, most preferably 90% or more (e.g., 95%, 96%, 97%, 98%, 99%, or more) over the entire amino acid sequence. Amino acid sequence identities and nucleotide sequences identities can be determined by using BLAST algorithm (Karlin, S. and Altschul, S. F., Proc. Natl. Acad. Sci. USA 87(6), 1990, 2264-2268; and Karlin, S. and Altschul, S. F., Proc. Natl. Acad. Sci. USA 90(12), 1993, 5873-5877). BLASTN and BLASTX programs have been developed based on the BLAST algorithm (Altschul, S. F. et al., J. Mol. Biol. 215(3), 1990, 403-410). When nucleotide sequences are analyzed using BLASTN, parameters are set to be, for example, score=100 and wordlength=12. When amino acid sequences are analyzed using BLASTX, parameters are set to be, for example, score=50 and wordlength=3. When BLAST and Gapped BLAST programs are used, default parameters for the respective program are used. Specific procedures of these analysis methods are publicly known.
DNAs which serve as an active ingredient in the agents of the present invention may be inserted into vectors. Vectors are not particularly limited, as long as they can allow introduced genes to be expressed in plant cells. For example, it is possible to use vectors comprising promoters for homeostatic gene expressions in plant cells (e.g., the promoter of the potato SK2 chitinase gene, the cauliflower mosaic virus 35S promoter, etc.), or vectors comprising promoters that are inducibly activated by external stimulation.
The term “agents” in the present invention may be the aforementioned DNAs or vectors into which the DNAs are inserted, and may be mixtures containing other components for use in the introduction into plant cells. For example, agents of the present invention include the aforementioned DNAs, vectors into which the DNAs are inserted, Agrobacteria into which the DNAs are introduced, and biochemical reagents and solutions comprising them.
Plants that demonstrate the transgene-dependent incompatibility can be produced by introducing into plant cells the aforementioned DNAs or vectors having the function of imparting transgene-dependent incompatibility to plants, and regenerating plants from the plant cells. Therefore, the present invention also provides methods for producing plants with transgene-dependent incompatibility.
The type of plant cells into which the aforementioned DNAs or vectors are introduced is not particularly limited as long as the transgene-dependent incompatibility can be imparted, and includes, for example, petunia , tobacco, tomato, and potato.
Plant cells into which the aforementioned DNAs or vectors are introduced are not particularly limited and may be in any form as long as they can be used to regenerate plants. For example, suspension-cultured cells, protoplasts, leaf discs, and calli can be used.
Introduction of the aforementioned DNAs or vectors into plant cells can be performed using methods known to one skilled in the art, such as polyethyleneglycol methods, electroporation, Agrobacterium -mediated methods, and particle gun bombardment. In the Agrobacterium -mediated methods, for example, according to the method by Nagel et al. (Nagel, R. et al. FEMS Microbiol. Lett. 67, 1990, 325-328), a DNA can be introduced into plant cells by introducing into Agrobacteria an expression vector to which the DNA is inserted, and infecting plant cells with the Agrobacteria via direct infection or by the leaf disc method.
Regeneration of plants from plant cells can be achieved according to the type of plants using methods known to one skilled in the art. For example, petunia shoots are regenerated on media containing auxin (indoleacetic acid (IAA)) and cytokine (benzylaminopurine (BAP)), and rooted and grown on media containing indolebutyric acid (IBA) (van der Meer I. M., Methods Mol. Biol. 111, 1999, 327-334). Torenia, tobacco, and gerbera plants can be regenerated by similar methods (Elomaa, P. et al., Plant J. 16, 1998, 93-99). Examples of methods for regenerating other plants include: Fujimura's method (Fujimura, T. et al., Plant Tissue Culture Lett. 2, 1985, 74-5) for rice; Shillito's (Shillito, R. D. et al., Bio/technology, 7, 1989, 581-587) and Gordon-Kamm's methods (Gordon-Kamm, W. J. et. al., Plant Cell. 2(7) 1990, 603-618) for corn; Visser's method (Visser, R. G. F. et al., Theor. Appl. Genet. 78, 1989, 594-600) for potato; Akama's method (Akama, K. et al., Plant Cell Reports, 12, 1992, 7-11) for Arabidopsis thaliana ; and Dohi's method (JP-A Hei 8-89113) for Eucalyptus.
Once a plant transformed through the insertion of an aforementioned DNA or vector into its genome is obtained, it is possible to obtain progenies or clones from that plant by sexual or asexual reproduction. In addition, propagating materials (such as seeds, fruits, cuttings, tubers, tuberous roots, lines, calli, protoplasts, etc.) can be obtained from the plant, or progenies or clones thereof, and used for large-scale production of the plant.
The present invention provides plants with the above-described transgene-dependent incompatibility, plant cells which can be used to regenerate such plants, progenies or clones of such plants, as well as propagating materials of such plants.
The methods of the present invention can be used to prevent the above-described plant transformants from spreading into the environment. The present methods can be applied as a useful means to other plants for suppressing the spreading of transgenic plants into the environment and contribute to raise acceptance of the general public towards transgenic plants. In addition, the present invention can also be considered for use in the production of pure line seeds. In order to obtain high quality seeds retaining a pure line of a particular variety, methods of physical isolation, such as covering with bags after mating and producing seeds in isolated islands to which mediating insects cannot fly (Matsushima Chinese cabbage), are currently performed to prevent contamination by genes of other varieties. These methods are bound to face difficulties such as considerable amounts of labor and geographical restriction. However, when the present invention is put into practice, such physical isolation may become unnecessary.
Any patents, published patent applications, and publications cited herein are ZPT2-10 to provide agents that impart transgene-dependent incompatibility to plants. ZPT2-10 to provide agents that impart transgene-dependent incompatibility to plants incorporated by reference.
EXAMPLES
The present invention will be specifically described using Examples, but it is not to be construed as being limited thereto.
Example 1
Preparation of SK2:ZPT2-10 Fusion Gene
A DNA fragment (940 bp) comprising the nucleotide sequence of the potato SK2 chitinase gene promoter region was excised from plasmid pSK2/1 (Ficker, M. et al., Plant Mol. Biol. 35, 1997, 425-431) with Xpai and NcoI. The pSK2/1 was kindly provided by Dr. Richard D. Thompson (Max Planc Institute, Germany). Meanwhile, a NcoI-ZPT2-10:NOS-terminator fragment was obtained by PCR using:
an upstream primer (5′-CAT GCC ATG GAT CTT CTA CAA GAT-3′/SEQ ID NO: 3) designed so that the NcoI site is inserted in the upstream of the ATG initiation codon in the ZPT2-10-coding sequence;
an M13 (−20) primer (Stratagem) carried by a pUC19 vector; and
as a template, a pUC-ZPT2-10-NT plasmid comprising in a pUC19 vector the ZPT2-10 cDNA (1,200 bp/SEQ ID NO:1) (Kubo, K. et al., Nucleic acids Res. 26, 1998, 608-615) and a NOS terminator sequence.
Then, the SK2 promoter fragment and the NcoI-ZPT2-10:NOS-terminator fragment were successively inserted into pBluescript SK+ to prepare SK2::ZPT2-10::NOS-terminator gene. The resulting gene was inserted into a pGreen 0029 binary vector (Hellens, R. P. et al., plant Mol. Biol. 42, 2000, 819-832) to obtain pGreen-SK2::ZPT2-10 ( FIG. 1 ).
Example 2
Introduction of SK2:ZPT2-10 Fusion Gene into Petunia Cells
According to the description of Hellens et al. (Hellens, R. P. et al., Plant Mol. Biol. 42, 2000, 819-832), pGreen-SK2::ZPT2-10 was mixed with a pSoup plasmid, and transfected into the Agrobacterium tumefaciens strain gv3101 by an electroporation method. The resulting Agrobacterium transformants were introduced into petunia by the leaf disc method (Jorgensen, R. A. et al., Plant Mol. Biol. 31, 1996, 957-973).
Example 3
Analysis of Crossing Properties
Pollen was collected from the anthers in flowers of the above-described SK2::ZPT2-10 gene-introduced petunia one to two days after flowering. Self-pollination was then performed by pollinating stigmas (5 cm or higher) of emasculated buds (one day before flowering) in the same plants. As a result, all plants produced normal seeds. On the other hand, when pistils of a wild-type strain were pollinated with pollens of the SK2::ZPT2-10 gene-introduced petunia , and vice versa, no fruition was observed in any of the three independent transformation lines used (Table 1 and FIG. 2 ). Such a phenomenon is called transgene-dependent incompatibility (TDI), and strains with such a crossing property are called the TDI strain. In TDI-strain petunias , abnormality is not recognized in traits other than the crossing property.
Table 1: Analysis of Crossing Properties
TABLE 1
♂(POLLEN PARENTS)
NON-
TDI-1
TDI-2
TDI-3
TDI
MWT
♀(PISTIL
TDI-1
87
100
89
0
0
PARENTS)
TDI-2
100
100
85
0
0
TDI-3
100
100
96
0
0
NON-TDI
0
0
0
100
100
MWT
0
0
0
100
100
FRUITION RATE (%)
n (POLLINATION TIME) = 4 to 20
Example 4
Inheritance of the TDI Trait
In order to obtain TDI strain T1 generation, T0 individuals of three independent TDI strains were mated with one another and seeds were obtained. The T1 generation was analyzed for its introduced genes and crossing properties, and the relationship between the gene that has been introduced and the observed crossing property was examined. In order to examine inheritance of the introduced SK2::ZPT2-10 gene, the presence of transgene-specific bands in genomic DNAs extracted from each individual was examined by Southern blot analysis (Sambrook, J. et al., Molecular Cloning: A Laboratory Manual, 2nd ed., Cold Spring Harbor Laboratory Press, 1989), using the ZPT2-10 cDNA as a probe. As a result, the T1 individuals were divided among those that have SK2::ZPT2-10 genes from both parents; those that have inherited the SK2::ZPT2-10 gene from one of the parents; and those that have not inherited the SK2::ZPT2-10 gene ( FIG. 3 ). T1 individuals from the respective groups were propagated by the same crossing method described in Example 3, and their crossing properties were examined. The results showed that all T1 individuals comprising the SK2::ZPT2-10 gene inherited from TDI-strain parents are fertile like their parent individuals if self-propagated or mated with other TDI strains, and are infertile when mated with the wild-type strain (Table 2). On the other hand, individuals not comprising the SK2::ZPT2-10 gene, except one individual, produced seeds through either of the mating patterns, and exhibited entirely normal crossing properties. These results showed that the TDI property has a strong connection with the introduced SK2::ZPT2-10 gene, and is stably inherited by progenies.
Table 2: Inheritance of the TDI Trait
TABLE 2
FERTILITY OF T0 AND T1 PLANTS
TDI♀ × TDI♂
PISTIL PARENTS
POLLEN PARENTS
(SELF-
TDI♀ ×
TDI♀ × ANOTHER
WT♀ ×
TDI♂ × ANOTHER
POLLINATION)
WT♂
STRAIN TDI♂
TDI♂
STRAIN TDI♀
PLANT
TRANS-
FRUITION
FRUITION
FRUITION
♂MATING
FRUITION
FRUITION
♀MATING
NAMES
GENES
RATE (%)
RATE (%)
RATE (%)
SPEICES
RATE (%)
RATE (%)
SPEICES
MWT
—
100
T0
TDI-1
abcg
87
0
100
TDI-2
0
100
TDI-2
TDI-2
de
100
0
100
TDI-1
0
100
TDI-3
TDI-3
f
100
0
100
TDI-2
0
100
TDI-2
T1
28a
a
88
0
100
93f
0
33a
a
86
20
100
15d
0
32b
b
100
0
0
36b
b
100
25
100
3df
0
100
25cf
72b
b
100
0
100
31f
22
100
93f
111c
c
92
0
0
100
25cf
15d
d
100
6
100
31f
0
100
33a
101e
e
100
0
0
100
33a
104e
e
100
0
0
17f
f
100
0
0
31f
f
100
0
100
11ef
0
100
72b
93f
f
100
0
100
72b
0
100
28a
25cf
cf
100
0
100
111c
0
44cf
cf
100
0
100
31f
0
100
25cf
3df
df
100
0
0
100
36b
11ef
ef
100
0
43
100
31f
T1
14 wt
—
100
85
80
(REVER-
113 wt
—
100
78
100
TANT)
B6 wt*
—
69
57
0
NON-
(1 COPY)
100
100
0
1T0
100
0
1T0
TDI-4
(n = 3~22)
(n = 4~16)
(n = 2~6)
(n = 2~8)
(n = 2~8)
Example 5
The post-pollination stage, at which abnormalities responsible for the infertility resulted from incompatible pollination between TDI individuals and wild-type plants occurred, was examined. The results show that the inhibition was not seen during the pollen tube elongation process and that pollen tubes had reached ovules normally. However, embryogenesis was found to discontinue after fecundation, and embryos died as a result of this ( FIG. 4 ).
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An objective of the present invention is to genetically improve plant crossing properties as to effectively prevent recombinant genes in transgenic plants from spreading into the environment. A TFIIIA-type zinc-finger transcription factor gene ZPT2-10 was introduced into petunia . As a result, some of the transformants (i.e., transgene-dependent incompatibility (TDI) strain plants) were found to have a useful crossing property. Specifically, the plants were fertile and produced normal seeds when self propagated or mated with another specified transformant comprising the same recombinant gene, but were infertile (transgene dependent incompatibility) when mated with another transformant strain that does not have the TDI property or with a wild-type plant. It may be possible to utilize plants having such a crossing property to prevent transgenic plants from spreading into the environment.
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BRIEF SUMMARY OF THE INVENTION
This invention relates to a process for preparing cyclic ethers directly from acetic acid esters of 1,4-glycols. More particularly, it relates to a process for preparing tetrahydrofuran or dihydrofuran from an acetic acid ester of 1,4-butanediol or 1,4-dihydroxybutene-2.
Tetrahydrofuran is known to be useful as a solvent for various kinds of materials, particularly polymeric materials such as polyvinyl chloride, polyvinylidene chloride, etc., and has been heretofore produced by a variety of processes. Typical of the processes are a process for catalytically hydrogenating furan obtained by decarbonization of furfural, a process wherein butynediol obtained by reacting acetylene and formaldehyde is hydrogenated to give butanediol, which is then dehydrated for ring formation, and a process which comprises reacting a diacetic acid ester of 1,4-butanediol with water in the presence of an acid catalyst. (Refer to British Patent 1170222).
It is known that production of a cyclic ether, particularly tetrahydrofuran, from an acetic acid ester of 1,4-glycol is conveniently feasible when water required for the reaction is used in an excess of that theoretically required and fed water as steam together with the starting ester to contact with a solid acid catalyst, followed removing the cyclic ether being produced in gas phase from the reaction system. (Refer to Offenlegungsshrift Nos. 2415663 and 2456780).
However, a large amount of water is contained in the reaction product discharged from the reactor when an excessive amount of water is used for the reaction. Since tetrahydrofuran and water readily form an azeotropic mixture, the reaction product must be repeatedly distilled in order to recover anhydrous tetrahydrofuran, thus requiring additional and complicate steps.
On the other hand, when the amount of water employed is reduced, there is a tendency of lowering the rate of conversion to some extent though the reaction product contains a reduced amount of water. This is very disadvantageous from an industrial point of view.
I have made an intensive study of a process, in which a reaction product can be obtained with high content of a cyclic ether and can be purified by a simple distillation procedure, and succeeded in obtaining a substantially water-free and high quality cyclic ether by a process which uses a reaction system including, in combination, two reaction zones and a plurality of distilling columns and in which part of a reaction product is fed back to a particular reaction zone.
An object of the present invention is to provide a process for preparing high quality cyclic ethers directly from acetic acid esters of 1,4-glycols in an industrially advantageous manner.
Another object is to produce a high quality cyclic ether substantially free from water by using a two reaction vessels in combination with a plurality of distillation columns.
The above object can be achieved according to the present invention by a process wherein a cyclic ether is prepared by interacting an acetic acid ester of 1,4-butanediol or 1,4-dihydroxybutene-2 and water in the presence of an acid catalyst in two reaction zones arranged in series, the process comprising the step of (a) continuously feeding to the first reaction zone the acetic acid ester and a mixture of the cyclic ether and water recycled from a first and a second distilling columns to effect the catalytic reaction; (b) withdrawing a gaseous mixture composed of a produced cyclic ether, water and acetic acid from the first reaction zone and feeding the gaseous mixture to the second distilling column; (c) feeding the solution discharged from the first reaction zone and fresh water to the second reaction zone and withdrawing the resulting a gaseous mixture of the cyclic ether, water and acetic acid from the second reaction zone; (d) feeding the gaseous mixture discharged from the second reaction zone to the first distilling column and recycling a mixture of the cyclic ether and water distilled from the top of the first distilling column to the first reaction zone while discharging acetic acid as a bottom product; (e) feeding a mixture of the cyclic ether and water distilled from the top of the second distilling column to the first reaction zone and at the same time, taking out a substantially water-free cyclic ether-containing product from the bottom of the second distilling column; and (f) subjecting said product obtained in the step (e) to further distillation to obtain the cyclic ether.
BRIEF DESCRIPTION OF THE DRAWING
The drawing is a flow chart and represents an embodiment of the present invention and is not meant to limit the subject matter as set forth in the claims.
DETAILED DESCRIPTION OF THE INVENTION
The acetic acid esters of 1,4-butanediol or 1,4-dihydroxybutene-2 usable as the starting material in the present invention include monoacetic acid esters and diacetic acid esters of 1,4-glycols such as 1,4-diacetoxybutane, 1-hydroxy-4-acetoxybutane, 1,4-diacetoxybutene-2, 1-hydroxy-4-acetoxybutene-2.
These acetic acid esters can be prepared by known various processes. For example, the acetoxylation reaction of butadiene, acetic acid and oxygen or molecular oxygen-containing gas in the presence of a palladium-base catalyst can be conducted and 1,4-diacetoxybutene-2 and 1-hydroxy-4-acetoxybutene-2 are separated from the acetoxylation product. Further, 1,4-diacetoxybutane and 1-hydroxy-4-acetoxybutane are obtainable by hydrogenating the above-mentioned acetoxylation reaction product in the presence of a nickel- or palladium-base catalyst and recovering from the hydrogenation product.
Such product contains mainly the above-mentioned acetic acid esters of glycol, but, depending on the reaction conditions or the manner of purification, the acetic acid esters may contain other isomers such as acetic acid esters of 1,2- or 1,3-glycol. In some cases, the acetic acid esters may contain butyl acetate and acetic acid secondarily produced by the hydrogenation step. It is preferable to use the acetic acid esters of 1,4-glycols, especially diacetic ester of 1,4-butanediol having a purity of above 99.5%.
1-hydroxy-4-acetoxybutane suitable as the starting material may be obtained by partial hydrolysis of the above-indicated 1,4-diacetoxybutane. In the practice of the invention, however, it is preferable to use 1-hydroxy-4-acetoxybutane which is prepared by reacting propylene with molecular oxygen and acetic acid in the presence of a palladium catalyst to give allyl acetate, subjecting the allyl acetate to OXO reaction to obtain 4-acetoxybutylaldehyde and then hydrogenating the aldehyde. The thus obtained 1-hydroxy-4-acetoxybutane may contain 2-methyl-3-acetoxypropyl alcohol which is derived from 2-methyl-3-acetoxypropionaldehyde secondarily produced upon the oxo reaction. However, the 2-methyl-3-acetoxypropyl alcohol does not appear to hinder the process of the invention.
The acid catalysts useful in the process of this invention should be those which are non-volatile, including liquid acids and solid acids. Examples of the liquid acids include inorganic acids such as sulfuric acid, phosphoric acid, etc., organic sulfonic acids such as benzene-sulfonic acid, toluenesulfonic acid, trifluoromethanesulfonic acid, etc. Of these, sulfuric acid is most preferable from a viewpoint of economy. Examples of the solid acids include activated clay, silica-titania, silica-alumina, silica-zirconia, chromia-alumina, silica-magnesia, natural and synthetic zeolites, a strong acid cation exchange resin and the like.
Though the amount of the acid catalyst may vary depending on the kind of the acid, the liquid acid is generally used in an amount of 0.01-100 parts by weight per part of the starting acetic acid ester. With the solid acid, it is frequently used as a catalyst bed packed in a column and is general to be employed in a liquid hourly space velocity (L.H.S.V. hr -1 ) of 0.001-10 though depending on the capacity of apparatus and the activity of the catalyst.
According to this invention water from any sources may be employed as one of the starting materials and it is desired to be free of chlorine ions. Preferably, water is fed as steam.
The process of the present invention will be particularly illustrated with reference to the accompanying drawing.
In the flow chart 21 and 22 represent the first and the second reaction zones respectively, 23 and 24 represent the first and the second distilling columns, and 25 represents a purifying column.
In the practice of the invention, the reaction is conducted in two reaction zones 21 and 22 arranged in series. The type and detail of such reaction zones are not critical and any reaction apparatus which ensure satisfactory gas-liquid contact may be used. Embodiments of the mode of reaction are as follows. (a) The reaction conveniently carried out by using a bubble column or an agitated reactor containing a catalyst (a liquid acid or a solid acid suspension bed), to which a liquid acetic acid ester of glycol is fed to form a liquid phase and simultaneously water or steam is introduced from the lower part of the column or reactor. The reaction may be conducted, if necessary, under exterior heating conditions. A multi-stage bubble column or a packed bubble column may be used as the bubble column. (b) To a column packed with a porcelain or metal packing such as Raschig rings, Berl saddles and Intalox saddles fed are a starting liquid acetic acid ester and a non-volatile acid catalyst. At the same time, steam is fed to the column for the reaction. Though the starting liquid materials and steam may be passed downwardly from the top of the column or upwardly from the bottom of the column in a vapor-liquid concurrent flow, it is preferable to countercurrently contact the vapor and the liquids with each other and most preferably, the starting liquid materials are passed downwardly from the top while the steam is fed upwardly. The resulting liquid reaction product, if necessary, may be circulated externally. The gas phase containing a produced cyclic ether and acetic acid is discharged from the reaction zone and fed to a distillation column.
In the above case, a multi-stage packed column may be used. Further, the reaction may be effected by a fixed bed system packing therein a solid acid catalyst instead of the packing.
The two reaction zones may be established by properly combining the reactors as mentioned above. That is, two reactors may be used to define the two reaction zones, or one reactor which is separated by a suitable means to define two reaction zones may be used. In some case, the two reaction zones may be each constituted of a multi-stage reaction zone.
In the accompanying drawings, the reaction zones are indicated at 21 and 22, and a packed column in the second reaction zone consists of two reaction zones. These reactors are essentially required to be acid proof. When, for example, a solid acid is used as catalyst, a SUS 316 stainless steel reactor is preferably employed. With a liquid acid, a SUS 316 stainless steel reactor is used when the reaction temperature is relatively low and a Hastelloy- or glass-lined reactor is used when the reaction temperature is relatively high.
The reaction temperature of the first and the second reaction zones is generally in the range of from 100° to 200° C, preferably 120° to 160° C. With the liquid acid catalyst, relatively low temperatures within the above-defined range are preferred, while, with the solid acid catalyst, relatively high temperatures above 120° C are preferably used.
The reaction pressure operable in the practice of the invention ranges from atmospheric pressure to 3 kg/cm 2 G, preferably atmospheric to 1 kg/cm 2 G.
Referring to the drawing, a starting acetic acid ester is fed to the reactor 21 through a pipe 1, and a liquid acid such as sulfuric acid serving as catalyst is fed to the reactor 21 through a pipe 2 with or without a reaction solution recycled through a pipe 3. To the reactor 21 are also fed through pipes 8 and 10 mixture of water and cyclic ether which are distilled off from the first and the second distilling columns 23 and 24, respectively, in the form of a gaseous phase, by which the catalytic reaction takes place by a countercurrent manner. The liquid reaction product discharged from the bottom of the reactor 21 and containing the unreacted starting materials, acid catalyst, acetic acid and the like is fed through a pipe 4 to the second reactor 22, to which fresh water is fed through a pipe 7 in the form of steam.
While, a gaseous mixture of the ether, water and acetic acid discharged from the reactor 21 is passed through a pipe 12 into the second distilling column 24 for distillation. The azeotropic gas mixture of water and the cyclic ether distilled out from the top of the column is recycled to the reactor 21 through the pipe 10 as mentioned hereinbefore. From the bottom of the column is obtained a distillate which contains acetic acid and the cyclic ether and which is substantially free of water. The distillate is passed into a purifying column 25 through a pipe 11 to give a pure cyclic ether product which is obtained from the top of the column 25 through a pipe 13. From the bottom of the column 25 is withdrawn a bottom containing acetic acid through a pipe 14.
The gaseous mixture containing the cyclic ether, water and acetic acid distilled from the top of the reactor 22 is fed to the first distilling column 23 for separating acetic acid therefrom. The cyclic ether-water mixture discharged from the top of the column is recycled to the first reactor 21 while discharging the acetic acid fraction from the bottom of the column. While, it is necessary to suitably withdraw from the bottom of the second reactor 22 through the pipe 6 the reaction solution mainly containing the catalyst and acetic acid in an amount corresponding to that of the starting materials to be fed to the reaction system.
The type of distilling columns and the purifying column may be any of conventional columns ordinarily employed for distillation. A multi-stage distilling column or a packed distilling column made of stainless steel SUS 316 is used for the purpose.
The distillation is generally conducted under conditions concluding number of the theoretical plates of 5-20, a pressure of atmospheric to 3 kg/cm 2 G, and a reflux ratio of 0.5-10.
If desired, the second distilling column may be composed of two distilling columns. That is, a mixture of cyclic ether and water is distilled off in one of the distilling columns while withdrawing acetic acid as a bottom, and the distilled mixture is then fed to the other column (which is desired to have a pressure higher by 2-15 kg/cm 2 than that of the first-mentioned column) to distil the cyclic ether and water in gas phase while discharging a substantially water-free cyclic ether from the bottom of the second-mentioned column. The distilled cyclic ether and water are fed to the first reactor.
As will be understood from the foregoing descriptions, the starting acetic acid ester is catalytically reacted with a small amount of water in the first reaction zone, so that the gaseous mixture discharged from the first reaction zone has a high concentration of the cyclic ether. Accordingly, a simple distillation operation is sufficient to separate the cyclic ether from the gaseous mixture to obtain a substantially water-free cyclic ether distillate. On the other hand, steam is fed to the second reaction zone in an amount much larger than the starting ester, with the attendant high rate of conversion of the ester. The gaseous mixture discharged from the second reaction zone is distilled in the first distilling column to separate acetic acid therefrom and a substantially all amount of the cyclic ether produced on the second reaction zone is recycled to the first reaction zone. From the above it will be understood that the process of the invention is much improved in efficiency without any losses of the starting esters.
The present invention will be particularly illustrated by way of the following example, which should not be construed as limiting the scope of the present invention in any manner.
EXAMPLE 1
The reaction was conducted using the reaction system shown in the accompanying drawing.
There were used as the reactors 21 and 22 Hastelloy reactor tubes each equipped with a heating jacket and having an inner diameter of 100 mm and a height of 7.5 m. Each of the reaction tubes was packed with 60 l of porcelain balls (with a diameter of 5 mm).
Pressure saturated steam of 140° C was passed into the jacket of the first reactor, to which were fed from the pipes 1 and 2,1,4-diacetoxybutane and sulfuric acid which had been preheated to 140° C, in amounts of 17400 g/hr and 980 g/hr, respectively. At the same time, 6020 g/hr of a gas distilled from the first distilling column 23 and 2590 g/hr of a gas distilled from the second distilling column 24, both of which had been preheated up to 140° C, were fed from the bottom of the first reactor 21 through the pipes 8 and 10, respectively. 11490 g/hr of the gaseous mixture of tetrahydrofuran (THF), H 2 O and acetic acid (AcOH) continuously discharged from the top of the first reactor 21 was passed into the second distilling column 24 through the pipe 12.
While, 15470 g/hr of the reaction solution containing the unreacted starting materials was continuously passed from the bottom of the first reactor 21 through the pipe 4 into the second reactor 22 which was heated by passing steam of 140° C through the jacket of the reactor 22 in the manner similar to the first reactor. To the second reactor 22 was simultaneously fed for the reaction 3560 g/hr of steam superheated to 140° C under atmospheric pressure through the pipe 7.
17500 g/hr of the gaseous mixture of THF, H 2 O and AcOH discharged from the upper side of the second reactor 22 was fed to the first distilling column through the pipe 5 while withdrawing 1570 g/hr of a solution containing the unreacted materials, high boiling point materials and sulfuric acid from the bottom of the second reactor through the pipe 6.
The first distilling column was made of SUS 316 stainless steel, had an inner diameter of 100 mm and a height of 10 m, and was packed with the Dickson packing. The gaseous mixture fed from the pipe 5 was charged at 5 m below the top of the column and the distillation was effected at a reflux ratio of 1.5 under an atmospheric pressure. 6020 g/hr of the gas (containing 82.2 mol % of THF) from the top of the column was recycled to the first reactor through the pipe 8, while 11480 g/hr of a bottom containing a major proportion of acetic acid was discharged through the pipe 9.
The second distilling column was similar in construction to the first distilling column. In the second distilling column, the gaseous mixture fed from the first reactor through the pipe 12 was distilled at a reflux ratio of 2.0 under an atmospheric pressure. 2590 g/hr of a solution composed of a THF-H 2 O azeotropic composition from the top of the column was passed into the first reactor through the pipe 10, while 8890 g/hr of a bottom was fed into the purifying column 25 through the pipe 11. The purifying column was constructed of similarly to the first distilling column and operated at a reflux ratio of 2.0 under an atmospheric pressure, thereby yielding 6850 g/hr of THF with a purity of 99.95% from the top of the column through the pipe 13. At the same time, 2040 g/hr of acetic acid was obtained from the bottom of the column through the pipe 14.
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This invention relates to a process for preparing tetrahydrofuran or dihydrofuran by reacting an acetic acid ester of 1,4-butanediol or 1,4-dihydroxybutene-2 and water in the presence of an acid catalyst with a high yield. The process is characterized in that the reaction is carried out in two separate reaction zone in combination with a plurality of distilling columns and a part of reaction product is recycled to a predetermined position of the reaction zone.
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FIELD OF THE INVENTION
The present invention relates to packaging and more particularly to a package for containing various components that can be erected into an elevated canopy.
BACKGROUND OF THE INVENTION
Elevated canopies are now being sold and used widely. Typically, these canopies include a series of vertically oriented support posts that support an overhead open frame structure from opposite sides. The overhead frame structure or roof frame is designed to accept a tarp. The tarp is effectively secured to the overhead frame structure by a series of elastic tie cords.
Kit-type canopies like that described above, are generally sold in an unpackaged form. That is, the various components that comprise the kit such as elongated pipes and corner connectors, are handled or bagged loosely. Obviously, the loose packaging of such a product makes the product as a whole difficult to promote, market and merchandise.
Therefore, there is a need for a package design that would accommodate a kit-type canopy of the type having a series of elongated pipes, corner connectors, and tarps.
SUMMARY AND OBJECTS OF THE INVENTION
The present invention entails a package containing a canopy kit made up of a series of elongated pipes and a series of corner connectors for connecting the respective elongated pipes. In addition, the package is provided with a tarp that forms the top of the canopy kit and an array of elastic tie cords for securing the tarp to the upper roof frame structure of the canopy kit.
The package structure of the present invention entails an elongated container having a bottom, a pair of side walls, a pair of end walls and a top. A series of corner connectors are longitudinally spaced in the package and each corner connector includes a series of arms projecting therefrom. These corner connectors when disposed within the container define an internal support structure within the package itself. A series of elongated pipes are disposed over the corner connectors and supported thereby.
In addition to the above, the formed package structure can contain additional corner connectors that are disposed over the elongated pipes within the package. These additional corner connectors include arms that extend transversely over the top of the elongated pipes and additional arms that extend downwardly between the side walls of the container and the pipes so as to generally isolate the pipes from the side walls of the container.
In a particular embodiment of the present invention, a series of corner connectors are longitudinally spaced throughout the elongated container. The various corner connectors form a series of transversely extending arms that extend transversely across the container. In addition, the same corner connectors include an array or series of vertically extending arms that extend upwardly adjacent an inner side of the side wall. Thus, the corner connectors form a three-sided disjointed open top frame structure for receiving a series of elongated pipes. The elongated pipes are laid into the container such that the pipes are supported over the transverse arms of the corner connectors while the vertically oriented arms extend adjacent the side walls of the container generally confine the pipes within the container from actually engaging the side walls of the container.
Also, the packaged canopy kit structure of the present invention includes a tarp and an array of elastic tie connectors or cords.
It is therefore an object of the present invention to provide a compact package structure for containing the individual components of a kit for a canopy.
Still a further object of the present invention resides in the provision of a package structure for the components of a canopy kit wherein the components are packaged in such a manner that the components themselves structurally reinforce the total package.
Other objects and advantages of the present invention will become apparent and obvious from a study of the following description and the accompanying drawings, which are merely illustrative of such invention.
BRIEF DESCRIPTION
FIG. 1 is a perspective view of the canopy structure of the present invention shown erected.
FIGS. 2-7 are a sequence of views illustrating the steps of packaging the container of the present invention.
FIG. 8 is a cross-sectional view of the package shown in FIG. 7.
FIG. 9 is a perspective exploded view of a second package design for the canopy kit of the present invention.
FIG. 10 is a side elevational view of the second package design with a near side wall and a top portion of the container being removed to better illustrate the packaging of the canopy kit components.
FIG. 11 is a cross-sectional view of the second package design.
FIG. 12 is a perspective view showing how a series of packages are stacked and supported.
DETAILED DESCRIPTION OF THE INVENTION
With further reference to the drawings, particularly FIG. 1, an erected canopy is shown therein and indicated generally by the numeral 10. Canopy 10 is of the type that is customarily manufactured and sold as a kit, with the kit including a series of component parts.
The present invention relates to a package structure for housing and containing the component parts of the canopy 10. However, before discussing the package structure of the present invention, it may be beneficial to briefly review the key components of the canopy 10 shown in FIG. 1.
First, the canopy 10 includes a series or group of pipes 12. The group of pipes 12 includes a series of vertical support posts 12a, side members 12b, ridge members 12c and rafter members 12d. Posts 12a typically comprise elongated metal pipes. As seen in FIG. 1, when the canopy 10 assumes an erect mode, the vertical posts 12a serve to support an overhead top frame or roof frame structure.
Viewing the top frame or roof frame structure of the canopy kit, it is seen that the same includes the series of side members 12b, a plurality of ridge members 12c, and a series of rafter members 12d. The side members 12b, ridge members 12c and rafter members 12d are also constructed of elongated metal pipe.
To connect the various components to the top frame and to connect the top frame to the vertical post 12a, there is provided a series of corner connectors. First, there is provided a group of three-way corner connectors 20. Each of the three-way corner connectors includes arms 20a, 20b, and 20c that project outwardly from a formed joint. Also provided is a series of four-way corner connectors 22. The four-way corner connectors 22 include a series of arms 22a, 22b, 22c and 22d, that project outwardly from a central joint. Corner connector is used herein to denote a component of the canopy kit and means a connector having at least two arms for interconnecting two pipes together. The corner connector can be located at any location on an erected canopy.
Also provided with the canopy kit is a tarp 24 that is of a poly or vinyl type. An array of elastic tie cords 26 is also provided and these tie cords function to tie the tarp 24 to various components of the top frame.
Various sized canopies can be configured. For example, a canopy can measure 10 ft. ×20 ft. or 10 ft.×10 ft. Other sizes can obviously be offered.
Now, turning to the package structure of the present invention, the canopy kit of the present invention is packaged within a cardboard container indicated generally by the numeral 40. Package 40 includes a bottom 42, a pair of side walls 44 and a pair of end walls 46. There is provided a top 48 for enclosing the package 40.
Turning to one embodiment of the present invention, a sequence of views is shown in FIGS. 2-8 that show the basic steps involved in packaging the components of a canopy kit. Note in FIG. 2, that a divider panel is inserted into the package 40 and stationed on the bottom 42 midway between the end walls 46. This divider panel includes a base 52 and an upstanding divider wall 50. As shown in FIG. 2, a series of pipes 12b and 12c are placed on each side of the divider wall 50 such that the wall effectively separates the two groups of pipes.
Next, as viewed in FIG. 3, a series of four-way corner connectors 22 are placed in the package 40. These four-way connectors 22 are longitudinally spaced. Note that the arms 22a and 22b are generally longitudinally aligned while arms 22c and 22d extend transversely across the container 40. Transversely oriented arms 22c and 22d tend to angle slightly upwardly from the axis formed by the longitudinally aligned arms 22a and 22b. Thus, arms 22c and 22d form an open V-shaped configuration or a shallow cradle structure.
The next step in the packaging process includes placing a series of pipes 12 (taken from the group of post and rafter members 12a and 12d) over the four-way corner connectors 22. See FIG. 4. Note that the transverse arms 22c and 22d form an open frame structure that underlies and supports the pipes 12 thereover.
Next, the three-way corner connectors 20 are disposed over the pipes as shown in FIG. 5. Note that the three-way corner connectors 20 are placed in the package 40 in opposed relationship. That is, the three-way corner connectors 20 are disposed in generally aligned pairs which are longitudinally spaced through the package. In particular, along each side of the package 40, there is provided a plurality of three-way connectors 20. Note that arm 20a extends cross the top of the pipes 12 and terminates generally midway of the container. Extending generally along the side walls 44 of the package 40 are the other two arms 20b and 20c of the three-way connector. In particular, arms 20b and 20c extend downwardly between the pipes 12 that rest on the four-way connectors 22 and the side wall 44. Effectively, arms 20b and 20c separate the adjacent pipes 12 from the side walls
Next, the container is provided with a tarp 24 and the elastic tie cords 26 (FIG. 6).
As seen in the drawings, the four-way corner connectors 22 in combination with the three-way corner connectors 20, form an open disjointed frame around the mass of pipes 12 supported the four-way corner connectors 22. Effectively, the three-way corner connectors 20 and the four-way corner connectors 22 form a frame structure around the upper group of pipes 12 supported by the four-way connectors and generally prohibit the upper group of pipes 12 from coming into contact with either the bottom 42 of the package or the side walls 44 of the package (FIG. 8).
In the package just described (FIGS. 2-7), the pipes disposed adjacent the bottom 42 include nine side and ridge member pipes 12b and 12c that in the embodiment illustrated, are approximately 6 ft. 6 in. long each. The nine pipes are divided by the divider wall 50, that is four pipes are on one side and five pipes on the other. Disposed over the four-way corner connectors 22 is a group of sixteen pipes. These pipes include the vertical posts 12c and the rafter member pipes 12d. In the embodiment illustrated, it is contemplated that the package would be approximately 81/2 inches wide, 15 inches high, and 79 inches long.
Now, turning to a second package structure as shown in FIGS. 9-11, it is seen that the base of the package structure comprises a series of three-way corner connectors 20 longitudinally spaced along the bottom 42 of the package. The three-way corner connectors 20 are aligned transversely in pairs. In particular, one arm 20a of each three-way connector extends transversely across the package while there is an adjacent arm 20a from an opposed three-way connector 20 that extends adjacent the same. The remaining arms 20b and 20c of each three-way connector 20 extends upwardly from the bottom in a V-shaped configuration adjacent respective side walls 44. In the embodiment illustrated in FIGS. 9-11, there is provided six three-way corner connectors 20, three on each side of the package.
Next, after the three-way corner connectors have been placed in the container, a series of pipes 12 are laid over the transverse arms 20a of the respective three-way corner connectors 20. In the case of the embodiment illustrated, there are a total of fourteen elongated pipes 12 laid over the transverse arms 20a. Note that the three-way connectors 20 form a generally U-shaped, open and disjointed frame structure within the package. As seen, the pipes 12 contained within the open disjointed frame formed by the three-way connectors 20 are isolated from the bottom 42 and side walls 44 of the package.
As with the first package embodiment described above, the package 40 shown in FIGS. 9-11 is provided with a tarp 24 and a series of elastic tie cords 26. It should be noted that the tarp 24 could be placed on top of the package. As shown in FIGS. 10 and 11, the tarp 24 is disposed on the bottom 42 of the package.
The canopy kit package as described immediately above, basically includes six three-way corner connectors 20 and fourteen elongated pipes. This forms a 10×10 canopy. Packaged, the container is of a size of approximately 11 inches wide, 6 1/2 inches high and 70 inches long.
It is appreciated that the various components for a canopy kit can vary in size, number, type, etc. As seen from the drawings, the various corner connectors 20 and 22 form an open disjointed frame structure for housing a substantial number of elongated pipes. This disjointed open frame structure tends to isolate the pipes 12 from portions of the cardboard container 40.
In the above discussion, two different package designs have been discussed for two separate canopy kits. It is appreciated that the package structure disclosed herein would be suitable for other canopy kits of various designs and sizes.
As illustrated in FIG. 12, individual packages 40 can be stacked on a palette and stabilized by a pair of end caps 60. Note that the end caps 60 are preferably formed of a cardboard structure and are secured around the ends of the respective packages 40 by staples or the like. This effectively tends to unitize a series of packages 40, causing them to be stabilized during transport and storage. In the end, the group of packages 40 can be displayed at a merchandising site while still on a palette or other support structure by simply removing or tearing away the pair of end caps 60.
The present invention may, of course, be carried out in other specific ways than those herein set forth without parting from the spirit and essential characteristics of the invention. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.
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The present invention relates to a canopy kit comprising a plurality of elongated pipes and a series of corner connectors and a package for containing the various kit components. An elongated container is provided and the various components of the kit, including the corner connectors and pipes, are disposed within the container such that the components of the kit structurally reinforce the total package and wherein the individual corner connectors are strategically disposed throughout the package so as to support the elongated pipes.
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The present invention relates to ferrofluidic suspension, dome type electrodynamic transducer, as well as the applications thereof to loudspeakers, geophones, microphones or the like.
BACKGROUND OF THE INVENTION
Axisymmetric, moving coil type electrodynamic loudspeakers generating acoustic waves in response to a current are known. The moving coil borne by a mandrel is integral with a diaphragm, and there exists two main types of loudspeakers according to the implementation of the diaphragm, the cone type and the dome type loudspeakers.
The general operating principle of a loudspeaker is based on the possibility to set in motion a cylindrical coil carrying an electric current and placed in a static magnetic field created by one or more annular or cylindrical fixed permanent magnet(s) which magnetization orientation is parallel to the revolution axis of the loudspeaker, a plurality of ferromagnetic parts channeling the magnetic field so as to bring him radially relative to the coil. The air gap is the place where the coil is located, the coil moves in a free space between faces of internal (toward the central symmetry axis of the loudspeaker) and external (toward the periphery of the loudspeaker) magnetic constructions (generating and/or channeling a magnetic field according to whether they comprise a magnet or not), relative to the mandrel. In the following, it will be referred to internal volume for the free space (comprising the internal part of the air gap) comprised between the mandrel and internal magnetic construction and to external volume for the free space (comprising the external part of the air gap) comprised between the mandrel and external magnetic construction. Magnetic constructions classically implemented in such loudspeakers use ferromagnetic parts to loopback the magnetic field of the magnet(s) in order for it to be able to go through the coil in this air gap. Finally, a loudspeaker comprises a rigid supporting construction called “frame” and enabling the basic components of the loudspeaker to be held in defined static and dynamic structural and functional relations.
In order for the coil to be correctly guided in the air gap, in particular for it not to rub against the edges of the vertical free space/air gap, and to be brought back to a defined rest position in absence of current, it is implemented suspension means of edge type (between the periphery of the diaphragm and the frame) and “spider” type (between the coil-bearing mandrel or the diaphragm and the frame). Besides the double guiding function, these suspension means also fulfill a pneumatic sealing function (in particular the edge) between the faces of the diaphragm, so as to avoid an acoustical short-circuit between the faces of the diaphragm, and a returning function (the edge and the spider) of the coil to a defined rest position.
For more precisions about the construction and the operation of loudspeakers, general explanations and examples about loudspeakers can be found for example in “HIGH PERFORMANCE LOUDSPEAKERS” by Martin Colloms, edited by WILEY, ISBN 0471 97091 3 PPC.
SUMMARY OF THE INVENTION
The present invention proposes to suppress the classical means of suspension for transducers and specially suspension means of edge and spider type in a dome type loudspeaker (circular, or even elliptical), the suspension being provided by implementation of ferrofluidic seals between the coil-bearing mandrel and the edges of the vertical free space in order to ensure at least a double guidance of the coil and a pneumatic tightness in the transducer.
Therefore, the invention relates to an electrodynamic transducer with a diaphragm comprising an electrodynamic motor in a yoke and in which can move a coil borne by a mandrel integral with the diaphragm, the mandrel being a shape generated by a globally linear generating line, the coil being placed in an air gap of a vertical free space in which it can move and which is defined, toward the center of the transducer, by an internal magnetic construction (which generates and/or channels the magnetic field according to whether it comprises a magnet or not), and toward the periphery of the transducer, by an external magnetic construction (which generates and/or channels the magnetic field according to whether it comprises a magnet or not).
According to the invention, the transducer comprises neither peripheral suspension nor internal suspension, the peripheral suspension being a suspension between the periphery of the diaphragm and the yoke, the internal suspension being a suspension between the diaphragm or the mandrel and the yoke, and the transducer comprises at least two magnetic field confinement means (depending on/integrated in or independent from the magnetic constructions) in the vertical free space in order to form by mean of a ferromagnetic liquid at least two ferrofluidic seals stepped in the vertical free space, fulfilling at least a double guidance of the coil and the pneumatic tightness between the front and rear faces of the diaphragm, at least one of the ferrofluidic seals being continuous.
In various embodiments of the invention, following means are used, which can be used alone or in any technically possible combinations:
the transducer is a geophone,
the transducer is a microphone,
the transducer is a loudspeaker, the diaphragm is a dome, the yoke is a frame, the peripheral suspension is an edge and the internal suspension is a “spider”,
the loudspeaker is of plane diaphragm (emitting part) type,
the loudspeaker is of concave diaphragm (emitting part) type,
the loudspeaker is of convex diaphragm (emitting part) type,
the loudspeaker is of concave and convex diaphragm (emitting part) type, (both concave and convex in different areas),
the magnetic field confinement means are inside the internal and/or external magnetic construction,
the magnetic field confinement means are outside the internal or external magnetic construction (specific devices are thus added, a traditional internal/external magnetic construction can thus be used and one or more specific magnetic field confinement devices can be added),
at least one of the ferrofluidic seals is discontinuous along the circumference of the mandrel,
at least one of the ferrofluidic seals is continuous along the circumference of the mandrel (it is pneumatically tight and allows isolation of the rear part of the diaphragm from the environment and avoids an acoustical short-circuit because of the absence of the diaphragm peripheral suspension, specially of the edge type),
the bottom of the vertical free space side opposite to the diaphragm (dome) is closed (air tight, and an external and unilateral continuous ferrofluidic seal is then sufficient to ensure the pneumatic tightness of the rear face of the diaphragm),
the bottom of the vertical free space side opposite to the diaphragm is opened (an internal and unilateral continuous seal is then sufficient to ensure the pneumatic tightness of the rear face of the diaphragm),
the seals are arranged at a high position on a same side of the coil(s) (either all above or all below),
in case of several coils, at least one of the seals is above or below the set of coils (the other seal(s) can be located between the coils or completely on the other side of the coils),
advantageously, the seals are arranged at a high position on either side of the coil (in the case of several coils, two terminal seals can be provided on either side of the coils and/or seals can be provided between each coil/set of coils),
at least one of the ferrofluidic seals is an internal and unilateral seal, the ferromagnetic liquid of said seal being arranged inside the internal volume (the internal volume is inside the coil-bearing mandrel, the ferromagnetic liquid being therefore located between the mandrel and the internal magnetic construction),
at least one of the ferrofluidic seals is an external and unilateral seal, the ferromagnetic liquid of said seal being arranged inside the external volume (the external volume is outside the coil-bearing mandrel, the ferromagnetic liquid being therefore located between the mandrel and the external magnetic construction),
at least one of the ferrofluidic seals is a bilateral seal, the ferromagnetic liquid of said seal being arranged inside the external volume and inside the internal volume, substantially at the same height for a same bilateral seal,
the transducer comprises only unilateral ferrofluidic seals, either exclusively external or exclusively internal,
advantageously, the ferrofluidic seals are arranged in the space in which the volume is the most reduced (in practice, on the face of the mandrel which does not bear the coil),
the ferrofluidic seals are external and unilateral seals, the coil is arranged inside the internal volume on the internal face of the mandrel and, when the seals are internal and unilateral seals, the coil is arranged inside the external volume on the external face of the mandrel,
the transducer further comprises a return mean for the coil,
the transducer further comprises a return mean for the coil, selected among one or more of the following means:
loading of the diaphragm by a closed volume on the backside of the dome, the internal magnetic construction being opened toward the closed volume; loading of the diaphragm by a closed volume on the backside of the dome, the internal magnetic construction being opened toward the closed volume which comprises an adjusting device for the internal pressure thereof, specially by adjustment of the temperature of the air contained in said closed volume (for a long-term balancing of the pressures between the closed volume and the external environment, with a long time constant relative to the frequencies to be reproduced); loading of the diaphragm by a quasi-closed volume on the backside of the dome, the internal magnetic construction being opened toward said quasi-closed volume, said quasi-closed volume comprising a minimal pneumatic leakage (generally, a pressure balancing mean having a long time constant) the time constant of which is very long relative to the frequencies to be reproduced, said leakage having specially the form of a porous material or of a port with a very small diameter or of a fine tube (of capillary or needle type) toward the outside of the transducer; a mechanical return mean, such as a spring or a resilient material, between the dome or the mandrel and a fixed part of the transducer; an electronic feedback control of the position of the coil; such a configuration of the coil and the internal and external magnetic constructions that a return force (rebalancing) is exerted on the coil by an electromagnetic effect (for example, such that the value of the self-inductance of the coil is maximal for a determined position of the coil along the height of the vertical free space, within the air gap) a deformation of the mandrel in the ferrofluidic seal area relative to the vertical generating line sweeping the mandrel, said deformation extending along the circumference of the mandrel being defined so as to create a return force proportional to the movement of the coil; further, implementing of vertical (or even oblique) ferrofluidic seal segments, each vertical seal segment being in relation with a deformation along a segment of a mandrel vertical (or oblique) generating line, the vertical (or oblique) deformations being defined so as to create a return force proportional to the movement of the coil; one or more (general or local) deformations in the area of the ferrofluidic seals, specially deformations along segments of mandrel vertical generating lines, said deformation being defined so as to create a return force proportional to the movement of the coil,
the transducer comprises two internal and unilateral ferrofluidic seals at least one of which is continuous, said ferrofluidic seals being arranged in concave deformations as seen from the inside of the mandrel (the magnetic field confinement means in the vertical free space are therefore arranged at these levels), the coil being arranged on the external face of the mandrel toward the external volume (the ferrofluid being therefore advantageously arranged inside the internal volume which is much smaller than the internal volume) and the diaphragm is loaded by a quasi-closed volume on the backside of the dome, the internal magnetic construction being axially opened toward said quasi-closed volume arranged on the backside of the internal magnetic construction, said quasi-closed volume comprising a pneumatic leakage the time constant of which is very long relative to the frequency to be reproduced, the leakage being a port with a very small diameter toward the outside of the transducer,
the transducer is of circular mandrel type,
the transducer is of elliptical mandrel type.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will now be exemplified, without thereby being limited, by the following description of an application to a loudspeaker and in conjunction with the following drawing:
FIG. 1 which shows a vertical section passing through the anteroposterior symmetry axis of a circular dome type loudspeaker according to the invention and with several examples of return means for the coil, some of which being shown in dotted line;
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The application to loudspeakers has shown in an embodiment that it is possible to obtain displacements of the coil of approximately +/−6 mm. More important displacements are also possible, in particular with field confinement means enabling a strong concentration of the magnetic field in the ferrofluidic seal areas, the mandrel being even able to slide over the seals which stay in place.
Besides improving the thermal dissipation, the ferromagnetic liquid, which tends naturally to position itself in areas in which the magnetic field is the greatest (the most concentrate) and/or the field variation is the highest, will be able to act as a pneumatic seal between the front side and the rear side of the diaphragm, if it is continuous, and, in all cases, it will ensure the translation guidance of the mandrel in the vertical free space, given the suppression of external mechanical guiding elements for the mandrel, such as the edges of the diaphragm and/or the “spiders”. To ensure this guiding function, it is preferable that at least two ferrofluidic seals (for at least a double guidance) be present at different heights along the mandrel in the vertical free space, and preferably on either side of the coil(s) winded on the mandrel. According to some variants, the ferrofluidic seals can be on only one side of the coil, in the height direction (either all above or all below), in particular in the case the field concentration system is distinct from the principal motor, as in the case of using a traditional motor and adding specific field concentration means on this traditional motor).
In FIG. 1 , the electrodynamic motor of the loudspeaker 1 having a dome 2 , with the coil 6 and the external 5 and internal 4 magnetic constructions thereof, thus comprises means 11 to create magnetic field concentrations in the vertical free space, at levels (heights) at which ferrofluidic seals, which can be internal or external, bilateral or unilateral ones, are desired. Preferably, each ferrofluidic seal is, along the circumference of the mandrel, in a single own plane perpendicular to the symmetry axis of the mandrel, as shown. According to some alternatives/variants, the seal along the circumference of the mandrel can draw a profiled curve (sinusoidal, triangular, square frieze, rectangular . . . ) and form a profiled seal. In the latter case, given that a same seal runs at different heights along the circumference of the mandrel, a single seal of this type can ensure a double guidance. These ferrofluidic seals are continuous (at least one of them) or discontinuous. Further, according to some variants, segments of vertical or oblique seals can be implemented. The field confinement means are adapted accordingly. It will be understood that the substantially horizontal parts of seals in deformations of the mandrel fulfill a predominant returning function, the (optionally) vertical or oblique parts of the seals in deformations of the mandrel ensuring a regular sliding of the mandrel and a possible returning function (according to the shape of the mandrel's deformations, in particular of the top and bottom ends thereof).
In FIG. 1 , two bilateral seals 12 have been implemented on either side of the mandrel 3 bearing the coil 6 , each bilateral seal 12 being comprised by an internal part 13 in the internal volume of the vertical free space, on the internal magnetic construction 4 side, and an external part 14 in the external volume of the vertical free space, on the external magnetic construction 5 side. The motor is inside a rigid frame, only a front part 7 of which has been represented, with fixation means to a support which can be for example the face of an enclosure. The external and internal magnetic constructions can be passive ones, that is to say only comprising guiding means for a magnetic field created in the other construction, or they can be active ones, that is to say they comprise one or more magnetic field generating means (one or more magnets of ring/pellet/composite/single-part type . . . ), or they can be of the mix type, that is to say they combine the two above types (one or more magnetic field generating means and magnetic field guiding means).
Then, by creating at least two field concentration areas distributed along the height of the mandrel, for example on either side of the coil (or of the coils/between the coils), it is possible to make ferromagnetic liquid seals at different heights of the mandrel. These ferrofluidic seals extend horizontally, at least between one of the two walls of the vertical free space and the respective face of the mandrel, forming an unilateral seal, and at most, they extend to a same given height, on one side, between a first of the two walls of the vertical free space and the respective face of the mandrel, and on the other side, between the other face of the mandrel and the second wall of the vertical free space, forming a bilateral seal. It will be understood that these seals (at least two seals stepped along the mandrel) ensure by themselves a holding and at least a double guidance of the mandrel (guiding function) in the vertical free space.
At least one of the ferrofluidic seals has to be continuous to provide an efficient pneumatic isolation (sealing function) between the front side and the rear side of the diaphragm, in the case in point a dome 2 . So, thanks to this continuous seal on the circumference of the mandrel (unilateral or bilateral seal), the rear part of the dome (inside the loudspeaker) is pneumatically isolate from the front part (on the front side of the dome and corresponding to the environment of the loudspeaker). It will be understood that the selection of a bilateral or an unilateral seal, and for the latter of the internal or external positioning thereof, can depend on whether the bottom of the vertical free space is opened or not toward the outside: if it is opened, it will then be necessary to arrange at least one continuous seal, on the internal space side (continuous internal and unilateral seal or bilateral seal, because the latter comprises both an internal part and an external part).
In FIG. 1 , it is also shown possible means for the returning of the coil to a predefined position (returning function) when this one is no longer electrically excited (or after the suppression of an incidental external bias). However, it is to be reminded that some of the possible return means can't be graphically represented in this simplified figure, and that is the case for the implementation of an electronic feedback control of the position of the coil or for a configuration of particular electrodynamic characteristics of the motor with its coil (for example, the maximal value of the self-inductance at a given position of the coil).
Regarding the return means which are visible in FIG. 1 , there are:
(in solid line) an implementation of a closed volume on the backside of the diaphragm, so as to thus load the dome, this closed volume, closed by a wall 9 , being in the case in point a quasi-closed volume 8 , because a minimal-leakage, in the form of a port 10 , has been provided. The time constant of the port (the time which is required to balance the pressures between the two sides of the port) is very long relative to the frequencies to be reproduced by the loudspeaker. The port has thus a very small diameter or can be replaced/supplemented by a porous material or by a fine tube (of capillary or needle type). It can be noticed that, in order to load the backside of the dome with that quasi-closed volume, arranged essentially on the backside of the motor, the central core of the motor is opened toward the backside of the loudspeaker;
(in dotted line) an implementation of a mechanical return mean, such as a spring 15 , between the dome 2 and the central fixed part of the motor, in the case in point the internal magnetic construction 4 ;
(in dotted line) an implementation of a mechanical return mean, such as a resilient material, between the mandrel and a fixed part of the motor, in the case in point the end of the mandrel at the bottom of the vertical free space by the perforated resilient diaphragm 16 .
It will be understood that the mechanical return means can be arranged at other places, for example the perforated diaphragm, in a resilient material, arranged on the backside of the dome, in place of the spring. Further, the mechanical return means have to exert balanced return forces on the circumference of the mandrel/dome so as to avoid the compromising of the guidance and, advantageously, to be implemented so as to obtain a return force proportional to the movement of the coil.
In another example embodiment of the return means, by optimization of the mandrel's shape, the mandrel generating line is no longer a vertical line on the whole height of the mandrel but presents concavities (or convexities according to the considered face) in areas in which the ferrofluid will be placed. Then, two internal and unilateral ferrofluidic seals are arranged in concavities of the mandrel, on either side (regarding the height) of the coil which is external relative to the mandrel. At least one of the ferrofluidic seals is continuous along the periphery (circumference) of the mandrel to ensure the sealing function. The deformations of the mandrel are defined so as to obtain a return force proportional to the moving of the coil.
Those different return means can be used alone or combined in a loudspeaker.
Generally and preferably, in case of at least two unilateral seals, these ones are either together on the inner side of the mandrel or together on the outer side of the mandrel (however, according to a variant, it is possible to alternate the unilateral seals on each side of the mandrel). The selection of the side where to place the unilateral seals can be linked to the fact that the coil forms a protuberance on the mandrel and that the mandrel will thus have to be spaced from the face (coil side) bounding the free space in front of the coil for the latter not to rub against said face, and the seals are then placed on the other side (if the coil is on the outer side of the mandrel, the seals will be on the inner side of the mandrel), and thus inside the smallest free volume. Then, the ferrofluid is advantageously arranged in the space in which the volume is the most reduced, for example, in FIG. 1 , advantageously inside the volume 13 rather than inside the volume 14 .
It will be understood that further embodiments are possible through combinations/suppressions/exchanges of described means or other conventionally known means without thereby departing from the general scope of the invention. Then, the ferrofluidic guidance can be implemented in a manner equivalent to two (or more) seals by mean of a set of vertical seals distributed on the circumference of the mandrel, preferably in an equiangular manner, it will be understood that the sealing function would no longer be present with these vertical seals only and that it is then necessary either to add a continuous circular seal or to link the vertical seals to each other along the circumference. A further advantage with the arrangement of vertical (or oblique or profiled) seals, when the mandrel has a corresponding deformation at their levels, is to avoid a possible rotation of said mandrel around the symmetry axis thereof. In a variant, one or more circular seals are associated to vertical seals, by joining each other. On the other hand, a circular seal can either be in a single horizontal plane or be profiled, and then be placed at different heights along the circumference. In all these cases, the field confinement means are adapted to the shape/construction of the seal(s). Finally, to improve the sliding of the mandrel over the ferrofluidic seals in the parts in which it is useful (in particular in the deformations of vertical or oblique segments of seals), the mandrel can be covered with a coating which is non-wettable by the ferrofluid (ferrofluidophobic). On the other hand, to improve the seal strength and the holding/returning of the mandrel, the mandrel can be covered with a coating which is wettable by the ferrofluid (the ferrofluid “catches” on the mandrel) (ferrofluidophilic), in the parts in which it is useful (in particular at the bottom of the deformations of the mandrel helping for the return means). Finally, in case of several coils on a same face of the mandrel, the spacing between the coils appears set back (it is the mandrel itself) relative to the coils themselves and it can also acts as an area in which a ferrofluidic seal can be confined.
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The invention relates to an electrodynamic transducer ( 1 ) with a dome type diaphragm ( 2 ), comprising an electrodynamic motor with a coil ( 6 ) borne by a mandrel ( 3 ) integral with the diaphragm suspended to a yoke ( 7 ), the coil being placed in an air gap of a vertical free space in which it can move and which is defined, toward the center, by an internal magnetic construction ( 4 ), and toward the periphery, by an external magnetic construction ( 5 ), wherein the suspension comprises neither peripheral suspension nor internal suspension, the transducer comprises at least two magnetic field confinement means ( 11 ) in the air gap in order to form by mean of a ferromagnetic liquid at least two ferrofluidic seals ( 12, 13, 14 ) stepped in the air gap, fulfilling at least the guidance of the coil and the pneumatic tightness between the front and rear faces of the diaphragm, at least one of the ferrofluidic seals being continuous. Application to loudspeakers.
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FIELD OF THE INVENTION
The present invention relates generally to a loom with a weft bobbin located outside the shed, the feeding of the weft into the shed being accomplished by shuttles which are brought into the shooting position by a rotary transporting drum, and more specifically to such a loom having a monitoring system to detect faults in the position of the shuttles and the transporting drum.
DISCUSSION OF THE PRIOR ART
Looms of the type mentioned above are already known. In a known loom with such shuttles a rotary transporting drum is used in order to bring the shuttles into the firing position, whereby the weft is introduced into the weft gripping device of the shuttle by means of compressed air. After passing through the shed the shuttle is braked in a braking device, the weft is detached and the shuttle is returned on a conveyor belt to the transporting drum. If such a movement sequence is not carried out correctly faults can occur in the woven product. This applies to all the movement sequences in which the shuttle is not positively moved. In many such prior art looms there is no monitoring or sensing system to detect such operating problems.
SUMMARY OF THE INVENTION
The present invention is a loom of the type indicated hereinbefore wherein all the essential movements of the shuttle are monitored, whereby if a fault occurs the loom is stopped and the fault indicated.
According to the invention the circular path of each shuttle is provided with monitoring devices at several points by means of which the shuttle movements can be checked on a time or phase basis or both. As a result the shuttle is monitored constantly as it travels throughout its path and the loom only continues to operate if each segment of movement of the shuttle has correctly taken place in its cylical path and this has been indicated.
BRIEF DESCRIPTION OF THE DRAWING
The features, advantages and objects of the present invention will be apparent from the following description when read in conjunction with the accompanying drawing in which:
Fig. 1 is a side view of a schematically represented loom with shuttles;
FIG. 2 is a plan view of the loom of FIG. 1;
FIG. 3 is a partial sectional view taken along the line III -- III of FIG. 1; and
FIG. 4 is a pictorial representation of the system components for monitoring the shuttle rotation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the drawing and more particularly to FIGS. 1 and 2 thereof, there is shown loom 1 having a frame, substantially comprising a left-hand side plate 2, a right-hand side plate 3 and a longitudinal member 4 interconnecting the two side plates 2 and 3. A motor 5 of conventional type such as a geared motor is positioned on or alongside the left-hand side plate 2 and by means of a belt drive 6 comprising pulleys and a belt, drives a longitudinal main shaft 7. The main shaft 7 is used to drive continuously or intermittently all the components necessary for the operation of the loom 1, including a warp beam (not shown), a warp 8, shafts 9 for opening, closing and changing the shed and a fabric beam (not shown) for winding on the fabric. Main shaft 7 also drives and/or actuates a shooting device 10, a gripping device 11, and a sley 12.
Shuttles 13 are brought into their firing position by a rotary transporting drum 14, are shot by shooting device 10 on sley 12 through the particular open shed, are braked by the gripping device 11 at the other end of the loom, are placed top downward on a conveyor belt 16 by a curved guide shaft or chute 15 (FIG. 3) which returns them to the transporting drum 14. Prior to shooting the shuttle 13, a weft 17 taken from a fixed weft bobbin 18, located outside the shed, via thread guides 19,20, is passed into the shuttle which is ready for firing with the interpositioning of a weft store 21 and is held by the same in sprung clips.
In loom 1 it is important that in addition to a monitoring device 22 for the warp threads and monitoring devices 23 and 24 for monitoring the weft and the thread position thereof, that the individual movement sequences of shuttle 13 are also monitored. To this end a non-contacting sensor 25 is incorporated in the gripping device 11 which determines the passage of the shuttle 13 and the precise entrance thereof into the gripping device. However, it is not enough to merely determine the correct position of shuttle 13 in gripping device 11 because it is also necessary to establish that the entry of shuttle 13 into gripping device 11 takes place in a particular zone in phase with the loom movement, for which purpose a sensor 26 is used.
It is also important to monitor by means of a further sensor 27 the regular dropping of the shuttle 13 introduced into chute 15 by gripping device 11.
In addition, it is important to establish the presence of a shuttle 13 in front of the transporting drum by using a further sensor 28. Finally, it is also essential that the movement and phase of transporting drum 14 be monitored by a further sensing device 29, 30.
The signals produced by sensors 22-30 can be processed in known manner, in that when a fault signal occurs the loom 1 is appropriately stopped and the point at which the fault has occurred is, for example, indicated by a corresponding visual signal. Further, the sensors may be of any well-known type.
FIG. 4 pictorially represents the interaction of sensors 25 to 30 provided for monitoring the rotation of shuttle 13. A control shaft 31, to which two contact pointers 32, 33 are fixed in different angular positions and which is driven by the main shaft 7 is used for checking the phase position. Together with the non-contacting sensors 26 and 30, contact pointers 32, 33 determine the phase position of the individual monitoring operations.
Errors in the passage of shuttles 13 are indicated on a visual indicating device 34. Sensors 25, 27 and 29 are connected by means of respective connecting lines 25a, 27a and 29a to the indicating device 34, with the interpositioning of comparators 35, 36. The phase position of sensors 25 and 27 is compared with that of sensor 26 in comparator 36 and the phase position of sensor 29 is compared with that of sensor 30 in comparator 35. If the corresponding relevant pulses do not coincide an indication takes place on indicating device 34. No comparison with the phase position is necessary for sensor 28, so that line 28a is directly connected with indicating device 34. Therefore an indication resulting from a fault detected by sensor 28, which may optionally be linked with the stopping of the loom, only takes place when a shuttle 13 is not supplied by conveyor belt 16 to transporting drum 14.
For graphical reasons the transporting drum 14 is shown twice in FIG. 4. Sensor 29 checks the correct position of transporting drum 14 by establishing the correct position of a locking lever 37, which is moved by an eccentric 38 and meshes with a tooth system provided on drum 14. If drum 14 is not in the correct position the locking lever cannot engage, which fault is detected by sensor 29 thereby stopping the loom and simultaneously indicating the error on indicating device 34.
As a result of the described monitoring device the movement sequences of shuttle 13, which are largely not positively performed, are accurately monitored, so that when a fault occurs, damage is avoided by immediately stopping loom 1. In addition when the problem is cleared, restarting of the loom is easily accomplished by known means.
The invention is not limited to the embodiments described and represented hereinbefore and various modifications can be made thereto by those skilled in the art which are within the scope of the invention.
A detailed explanation of the operation of the loom with the monitoring system of this invention and specific examples of its operation follow hereinbelow. The loom makes one complete cycle for each revolution of 360° of the main shaft 7. The 0° position of shaft 7 coincides with the end of the time during which sley 12 is still stationary in a position in which it is completely to the rear of the weaver's station. At 50° the sley is fully advanced (for beating-up) and at 100° the sley is back in its fully rearward position and stationary. At 110 to 115°, the shuttle is picked. At 305° the contact pointer 32 is in front of proximity detector 26 (FIG. 4); if any single one of the electronic circuits of the memory kind (proximity detectors 25, 27, 29 or 30) refuses to permit further motion of the loom, detector 26 outputs a stop signal to the electronic control station 34. At the control station the signal from sensor 26 triggers release of the electro-mechanical coupling between the loom driving motor 5 and belt drive 6 while simultaneously engaging an electro-magnetic braking disk. Even at very high loom speeds the loom stops at about 340° to 345°, that is, early enough for the sley not to have begun its movement for the next cycle.
The number of gripper shuttles 13 circulating in the loom under consideration and in similar looms is from 25 to 30 per second depending upon the working width of the loom and upon the speed of the shuttle return belt 16. The non-positive movements of the gripper shuttles of the loom under consideration and which the present invention seeks to monitor are as follows: a) the flight of the shuttle through the shed in appropriate guides on the sley; b) the dropping (with overturning) of the shuttle from the gripping device 11 to the shuttle return belt 16; and c) correct insertion of the shuttle in the appropriate recess in drum 14 on the picking side from the shuttle return belt 16. The electronic controls of this invention also provide the following checks: d) proper position of drum 14 on the picking side; e) integrity of all warp yarns (warp stop motion); and f) integrity of the weft yarn.
If, for example, there are 25 shuttles circulating in the loom, at 305° the proximity detector 26 (FIG. 4) does not stop the loom if the 25th shuttle, that is, the shuttle most recently picked, has reached the gripping device 11 before 305°, that is, if the proximity detector 25 has given permission for the loom movement to continue. Nor does the loom stop if the 24th shuttle, that is, the penultimately picked shuttle, has entered the chute 15 properly and if the proximity detector 27 has given permission for loom movement to continue.
If a shuttle thrust by the conveyor belt has entered its proper groove or recess in the picking side drum 14 but in a different way so that part of the shuttle is in the drum groove and part is remaining on the shuttle return belt, a safety trap or door or the like would have triggered proximity detector 28 which would in turn have stopped the loom. Proximity detector 29 permits loom movement to continue if drum 14 has rotated through one 18th of a revolution to bring the first gripper shuttle into the line for picking. Proximity detector 30 permits loom movement to continue if the signal from the weft stop motion 23 (FIG. 2) has not been interrupted between the departure and the arrival of the 25th shuttle. Also, the warp stop motion 22 (FIG. 2) must be opened electrically if the electronic control station is not to stop the loom.
The invention is not limited to the embodiments described and represented hereinbefore and various modifications can be made thereto by those skilled in the art which are within the scope of the invention.
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A monitoring system for the shuttle movements in a loom of the multiple moving shuttle type. Sensors are located at the end of shuttle travel through the shed, at the beginning and end of its recycling travel back to the transporting drum, and phase sensors are provided to indicate proper position of the transporting drum. Whenever any of the sensors detects a fault in the position or phase of the shuttle or transporting drum, the fault is indicated and the loom is normally shut down until the fault is cleared.
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FIELD OF INVENTION
[0001] This invention relates to control of timing of a charge pump.
BACKGROUND
[0002] Various configurations of charge pumps, including Series-Parallel and Dickson configurations, rely of alternating configurations of switch elements to propagate charge and transfer energy between the terminals of the charge pump. Energy losses are associated with propagation determine the efficiency of the converter.
[0003] Referring to FIG. 1 , a single phase Dickson charge pump 100 is illustrated in a step-down mode coupled to a low voltage load 110 and high voltage source 190 . In the illustrated configuration, generally the load is driven (on average) by a voltage that is ⅕ times the voltage provided by the source and a current that is 5 times the current provided by the source. The pump is driven in alternating cycles, referred to as cycle 1 and cycle 2, such that the switches illustrated in FIG. 1 are closed in the indicated cycles. In general, the duration of each cycle is denoted T and the corresponding switching frequency F=½T.
[0004] FIGS. 2A-B illustrate the equivalent circuit in each of cycles 2 and 1, respectively, illustrating each closed switch as an equivalent resistance R. Each of the capacitors C 1 through C 4 has equal capacitance C. In a first conventional operation of the charge pump, the high voltage source is a voltage source, for example, a v in =25 volt source, such that the load is driven by v out =5 volts. In operation the voltage across capacitors C 1 through C 4 are approximately 5 volts, 10 volts, 15 volts, and 20 volts, respectively.
[0005] One source of energy loss in the charge pump relates the resistive losses through the switches (i.e., through the resistors R in FIGS. 2A-B ). Referring to FIG. 2A , during cycle 2, charge transfers from capacitor C 2 to capacitor C 1 and from C 4 to C 1 . The voltages on these pairs of capacitors equilibrate assuming that the cycle time T is sufficiently greater than the time constant of the circuit (e.g., that the resistances R are sufficiently small. Generally, the resistive energy losses in this equilibration are proportional to the time average of the square of the current passing between the capacitors and therefore passing to the load 110 . Similarly, during cycle 1, capacitors C 3 and C 2 equilibrate, capacitor C 4 charges, and capacitor C 1 discharges, also generally resulting in a resistive energy loss that is proportional to the time average of the square of the current passing to the load 110 .
[0006] For a particular average current passing to the load 110 , assuming that the load presents an approximately constant voltage, it can be shown than the resistive energy loss decreases as the cycle time T is reduced (i.e., switching frequency is increased). This can generally be understood by considering the impact of dividing the cycle time by one half, which generally reduces the peak currents in the equilibration by one half, and thereby approximately reduces the resistive energy loss to one quarter. So the resistive energy loss is approximately inversely proportional to the square of the switching frequency.
[0007] However, another source of energy loss relates to capacitive losses in the switches, such that energy loss grows with the switching frequency. Generally, a fixed amount of charge is lost with each cycle transition, which can be considered to form a current that is proportional to the switching frequency. So this capacitive energy loss is approximately proportional to the square of the switching frequency.
[0008] Therefore, with a voltage source and load there an optimal switching frequency that minimizes the sum of the resistive and capacitive energy losses, respectively reduced with increased frequency and increased with increased frequency.
SUMMARY
[0009] In one aspect, in general, cycle timing of a charge pump is adapted according to monitoring of operating characteristics of a charge pump and/or peripheral elements coupled to the charge pump. In some examples, this adaptation provides maximum or near maximum cycle times while avoiding violation of predefine constraints (e.g., operating limits) in the charge pump and/or peripheral elements.
[0010] In another aspect, in general, an apparatus has a charge pump having a plurality of switch elements arranged to operate in a plurality cycles. These cycles switch according to a timing pattern. Each cycle is associated with a different configuration of the switch elements, with the switch elements being configured to provide charging and discharging paths for a plurality of capacitive elements. A controller is coupled to the charge pump with an output for controlling the timing pattern of the switching of the cycles of the charge pump and one or more sensor inputs for accepting sensor signals charactering operation of the charge pump and/or operation of peripheral circuits coupled to the charge pump. The controller is configured adjust the timing pattern of the cycles of the charge pump according variation of the one or more sensor inputs within cycles of operation of the charge pump.
[0011] Aspects may include one or more of the following features.
[0012] The controller is configured to adjust the timing pattern of the switching of the cycles of the charge pump by adjusting a cycles switching frequency of the charge pump.
[0013] The controller is configured to adjust the timing pattern of the switching of the cycles of the charge pump by determining a switching time to end each successive cycle according to variation of the or more sensor inputs during said cycle.
[0014] The one or more sensor inputs comprise an output voltage sensor input representing an output voltage of the charge pump, and wherein the controller is configured to adjust the timing pattern according to variation of the output voltage sensor input.
[0015] The controller is configured to adjust the timing pattern to maintain the variation of the output voltage with a desired range, for instance, the desired range comprises a fixed range.
[0016] The desired range comprises a range dependent on a second sensor input of the controller.
[0017] The second sensor input represents an output voltage of a regulator coupled to the output of the charge pump, and the controller is configured to adjust the timing pattern to maintain a desired voltage margin between the output of the charge pump and the output of the regulator.
[0018] The one or more sensor inputs comprise a regulator sensor input representing operating characteristic of a regulator coupled to the output of the charge pump.
[0019] The regulator sensor input represents an output voltage of the regulator.
[0020] The regulator sensor input represents a duty cycle of switching operation of the regulator.
[0021] The one or more sensor inputs comprise an internal sensor input representing an internal signal of the charge pump.
[0022] The internal signal comprises a voltage across a device in the charge pump, and wherein the controller is configured to adjust the timing to maintain the voltage across the device within a predetermined range.
[0023] The charge pump comprises a Dickson charge pump.
[0024] Advantages of one or more aspects can include providing efficient power conversion while maintaining voltages and/or currents within desired operating ranges. For example, switching frequency may be reduced while still maintaining internal voltages or currents across circuit elements (e.g., voltages across transistors or capacitors) within desired ranges for those elements.
[0025] Other features and advantages of the invention are apparent from the following description, and from the claims.
DESCRIPTION OF DRAWINGS
[0026] FIG. 1 is a single-phase 1:5 Dickson charge pump;
[0027] FIGS. 2A-B are equivalent circuits of the charge pump of FIG. 1 in two states of operation;
[0028] FIGS. 3 and 4 are circuits having a switchable compensating circuit coupled to the charge pump;
[0029] FIG. 5 is a circuit for measuring a charge pump current;
[0030] FIG. 6 is a schematic illustrating charge transfer during one cycle of the charge pump illustrated in FIG. 4 ;
[0031] FIGS. 7A-C are graphs of output voltage of the charge pump illustrated in FIG. 4 at different output current and switching frequency conditions; and
[0032] FIG. 8 is a single-phase series-parallel charge pump.
DESCRIPTION
[0033] As introduced above, as one example, a charge pump 100 illustrated in FIG. 1 may be operated in an “adiabatic” mode in which one or both of a low-voltage peripheral 110 and a high-voltage peripheral 190 may comprise a current source. For example, Patent Publication WO 2012/151466, published on Nov. 8, 2012, and incorporated herein by reference, describes configurations in which the source and/or load comprise regulating circuits. In particular, in FIGS. 1 and 2 A-B, the low-voltage load 110 can effectively comprise a current source rather than a voltage source in an example of what is referred to as “adiabatic” operation of a charge pump. If the current source maintains a constant current from the charge pump, then currents illustrated in FIG. 2A maintain substantially constant values during the illustrated state. Therefore, the resistive losses in the switches through which the current passes are lower than the resistive loss in the voltage load case, and also substantially independent of the switching frequency and the cycle time T. As in the voltage driven case, there capacitive losses in the switches grow with increasing switching frequency, which suggests that lowering the switching frequency is desirable. However, other factors, which may depend on internal aspects of the charge pump, voltage or current characteristics at the terminals of the charge pump, and/or internal aspects of the peripheral elements, such as the source and/or load, may limit the cycle time (e.g., impose a lower limit on the switching frequency).
[0034] Referring to FIG. 3 , in a first mode of operation, a load 320 can be considered to comprise a constant current source 312 with an output current IO. In some implementations, the load 320 also includes an output capacitor, which for the analysis below can be considered to be small enough such that current passing to the load 320 can be considered to be substantially constant. As introduced above with reference to FIGS. 2A-B , the charge transfer between capacitors in the charge pump 100 during the alternating states of operation of the charge pump 100 are therefore substantially constant in the adiabatic mode of operation.
[0035] Continuing to refer to FIG. 3 , a compensation circuit 340 is introduced between the charge pump 100 and the load 320 . A switch 344 is controllable to selectively introduce a compensation capacitor 342 to the output of the charge pump 100 .
[0036] Various factors can affect the efficiency of the power conversion illustrated in FIG. 3 , including the voltage of an input voltage source 392 , the switching frequency of the charge pump 100 , and the output current IO (or somewhat equivalently the input or output current of the charge pump 100 ). The efficiency is also dependent on whether or not the compensation capacitor 342 is coupled to the output path via the switch 344 . As a general approach, a controller 350 accepts inputs that characterize one or more factors that affect efficiency and outputs a control signal that sets the state of the switch 344 according to whether efficiency is expected to be improved introducing the compensation capacitor versus not. A further discussion of logic implemented by the controller 350 is provided later in this Description.
[0037] Referring to FIG. 4 , in another example, a configuration of a charge pump 100 has a regulator 320 coupled via a compensation circuit 340 to the low-voltage terminal of a charge pump 100 , and a voltage source 392 coupled to the high-voltage terminal of the charge pump 100 . The regulator 320 (also referred to below generally interchangeably as a “converter”) illustrated in FIG. 4 is a Buck converter, which consists of switches 322 , 324 , an inductor 326 , and an output capacitor 328 . The switches open and close (i.e., present high and low impedance, respectively) in alternating states, such that the switch 322 is open when then the switch 324 is closed, and the switch 322 is closed when the switch 324 is open. These switches operate at a frequency than can be lower, higher, or equal to the switches in the charge pump 100 , with a duty cycle defined as the fraction of time that the switch 322 in the regulator 320 is closed. A preferred embodiment is when the switching frequency of the charge pump 100 is lower than the regulator 320 . However, in the case the charge pump 100 is at a higher frequency than the regulator 320 , the charge-pump 100 is disabled when the regulator 320 is off (low duty cycle) and the charge-pump 100 is enabled when the regulator 320 is on.
[0038] In general, the regulator 320 operates at its highest power efficiency when it operates at its highest duty cycle. In some examples, a controller of the regulator (not shown) adjusts the duty cycle in a conventional manner to achieve a desired output voltage VO. During the cycles of the regulator 320 in which the switch 322 is closed, the current passing from the charge pump 100 to the regulator 320 is effectively constant, equal to the current through the inductor 326 . Assuming that the switching frequency of the regulator 320 is substantially higher than the switching frequency of the charge pump 100 , the charge pump 100 can be considered to be driven by a pulsed current source with an average current equal to the duty cycle times the inductor current.
[0039] Note that as introduced above, in situations in which the regulator 320 sinks a pulsed current, then for a particular average current, the resistive energy loss generally increases as the duty cycle of the current decreases, approximately inversely with the duty cycle. There is a range of low duty cycles, and thereby high peak current relative to the average current, in which the resistive losses with a pulsed current exceed the losses for the same average current that would result from the charge pump 100 driving a relatively constant output voltage, for example, across a large output capacitor. Therefore, for a selected range of low duty cycles, the controller 350 closes the switch 344 and introduces a relatively large compensation capacitor 342 at the output of the charge pump 100 . The result is that the charge pump 100 is presented with a substantially constant voltage, and therefore operates in a substantially “non-adiabatic” mode. Therefore, the controller 350 is effectively responsive to the output voltage because the duty cycle is approximately proportional to the output voltage. Thereby operating the charge pump 100 in an adiabatic mode at high output voltage and in a non-adiabatic mode at low output voltage; and switches between the adiabatic and non-adiabatic modes at a threshold duty cycle to maintain an optimum efficiency of the overall power conversion.
[0040] Examples of control logic implemented in the controller 350 in configurations such as those illustrated in FIGS. 4 and 5 can be under in view of the following discussion.
[0041] In general, a charge pump can operate in one of two unique operating conditions, or in the region in between them. In a slow switching limit (SSL) regime the capacitor currents in the charge pump have the time to settle to their final values and capacitor voltages experience significant change in magnitude from beginning to end of a cycle of the charge pump operation. In the fast switching limit (FSL) regime, the capacitors do not reach equilibrium during a cycle of the charge pump operation, for instance, due to a combination of one or more of high capacitances, high switching frequency, and high switch resistances.
[0042] Another factor relates to the capacitance at the output of the charge pump 100 , which in the circuits of FIG. 4 can be increased by closing the switch 344 to add the compensation capacitor 342 to the output. For small output capacitance, the output current of the charge pump 100 is effectively set by the pulsed current characteristic of the regulator 320 . As discussed above, for a given average current, the resistive power losses in the pulsed current case are approximately inversely proportional the duty cycle.
[0043] For large output capacitance, the RMS of the output current of the charge pump 100 is effectively determined by the equilibration of the internal capacitors of the charge pump 100 with the compensation capacitor 342 and the regulator 320 . For a given average current, this resistive power loss is approximately inversely proportional to the square of the peak-to-peak voltage across the internal capacitors in the charge pump 100 .
[0044] Four combinations of FSL/SSL and constant/pulsed IO modes of operation are possible. In some examples, each of these four modes is affected in different ways based on the addition of a compensation capacitor 342 as shown in FIGS. 3 and 4 .
[0045] Case one: In FSL mode, with constant output current IO as in FIG. 3 , introduction of the compensation capacitor 342 does not substantially affect conversion efficient.
[0046] Case two: In FSL mode with pulsed output current as in FIG. 4 , efficiency increases when the compensation capacitor 342 is introduced, thereby reducing the RMS current seen by the charge pump 100 .
[0047] Case three: In SSL mode, with constant output current IO as in FIG. 3 , efficiency generally increases without introduction of the compensation capacitor 342 , thereby yielding adiabatic operation.
[0048] Case four: In SSL mode, with pulsed load current as in FIG. 4 , efficiency depends on the relation between the average output current, the duty cycle, and how far the charge pump 100 is operating from the SSL/FSL boundary. For example, at low duty cycle, efficiency generally increases with introduction of the compensation capacitor 342 , thereby yielding non-adiabatic operation. In contrast, at high duty cycle, efficiency generally increases without introduction of the compensation capacitor 342 , thereby yielding adiabatic operation. Furthermore, when the charge pump 100 is in SSL mode, the farther from the SSL/FSL boundary, the lower the duty cycle at which the efficiency trend reverses.
[0049] Depending on the relative values of charge pump capacitors, switch resistances and frequency, it is possible that the charge pump operate in a regime between FSL and SSL. In this case, there is effectively a transition point between case four and case two at which the compensation capacitor is introduced according to the overall efficiency of the conversion. As described above, knowledge of the average charging current and its duty cycle is necessary in case four for determining if introduction of the compensation capacitor will improve efficiency.
[0050] In some implementations, the controller 350 does not have access to signals or data that directly provide the mode in which the power conversion is operating. One approach is for the controller to receive a sensor signal that represents the input current of the charge pump, and infer the operating mode from that sensor signal.
[0051] As an example, a sensor signal determined as a voltage across the switch at the high voltage terminal of the converter (e.g., the switch between source 109 and the capacitor C 4 in FIG. 1 ) can be used to represent the current because when the switch is closed, the voltage is the current times the switch resistance.
[0052] An alternative circuit shown in FIG. 5 provides a scaled version of the input current IIN. The input switch 510 , with closed resistance R is put in parallel with a second switch with closed resistance kR, for example, fabricated as a CMOS switch where the factor k depends on the geometry of the switch. When the switches are closed the differential amplifier 530 controls the gate voltage of a transistor 540 such that the voltage drop across the two switches are equal, thereby yielding the scaled input current IIN/k, which can be used to form a sensor input signal for the controller.
[0053] The sensed input current can be used to determine whether the compensation capacitor should be switched in, for example, according to a transition between case four and case two described above.
[0054] One possible method for determining the operation mode of the charge pump 100 consists of taking two or more measurements of the input current IIN and establishing that the difference between the values of consecutive samples is substantially zero for SSL mode, or is above a pre-determined threshold for FSL mode.
[0055] Another method is to measure the difference in the voltage of a capacitor in the charge pump 100 . Once the input current IIN is known, the controller 350 can infer the operating mode based upon the voltage ripple on the capacitor over a full cycle. Note that the controller 350 does not necessarily know the particular sizes of capacitors that are used in the charge pump 100 , for example, because the capacitors are discrete capacitors that are not predetermined. However, the capacitor values can be inferred from knowledge of the current, voltage ripple, and frequency, thereby allowing the controller 350 to determine whether the charge pump 100 is operating in the FSL or SSL mode. The controller 350 can then select adiabatic or non-adiabatic charging by controlling the switch 344 to selectively introduce the compensation capacitor 342 .
[0056] Other controller logic is used in other implementations. For example, an alternative is for the controller to measure efficiency given by:
[0000] η= VO /( N*VIN )
[0057] where η is the efficiency, VO is the measured converter output voltage, VIN is the measured converter input voltage, and N is the charge pump conversion ratio.
[0058] The controller directly measures the effect of selecting adiabatic vs. non-adiabatic charging on converter efficiency by comparing the average value of the output voltage VO over a complete charge pump cycle.
[0059] Other controller logic uses combinations of the approaches described above. For instance, the controller can confirm that the assessment of charge pump operating mode and estimation of efficiency increase by changing the charge pump charging mode.
[0060] A traditional method for operating the charge pump 100 at a fixed frequency in which the switching occurs independently of the load requirement (i.e., the switches in FIG. 1 operate on a fixed time period). Referring to FIG. 6 , during one cycle of the switching of the charge pump 100 , a current I 1 discharges from the capacitor C 1 and a current IP discharges other of the capacitors in the charge pump 100 . For a particular intermediate current IX, the longer the cycle time T, the larger the drop in voltage provided by the capacitor C 1 . A consequence of this is that the switching frequency generally limits the maximum intermediate current IX because the switching frequency for a particular load determines the extent of voltage excursions, and in some cases current excursions (i.e., deviations, variation), at various points and between various points within the charge pump 100 and at its terminals. For a particular design of charge pump 100 , or characteristics of load and/or source of the charge pump 100 , there are operational limits on the excursions.
[0061] Referring to FIGS. 7A-C , the intermediate voltage VX of the charge pump 100 is shown in various current and timing examples. Referring to FIG. 7A , at a particular intermediate current IX, the intermediate voltage VX generally follows a saw-tooth pattern such that it increases rapidly at the start of each state, and then generally falls at a constant rate. Consequently, the rate of voltage drop depends on the output current IO. At a particular output current IO and switching time, a total ripple voltage 6 results, and a margin over the output voltage VO is maintained, as illustrated in FIG. 7A . (Note that the graphs shown in FIGS. 7A-B do not necessarily show certain features, including certain transients at the state transition times, and related to the high frequency switching of the regulator 320 ; however these approximations are sufficient for the discussion below).
[0062] Referring to FIG. 7B , in the output current IO in the circuit in FIG. 4 increases, for instance by approximately a factor of two, the ripple of the intermediate voltage VX increases, and the minimum intermediate voltage VMIN decreases and therefore for a constant output voltage VO the margin (i.e. across inductor 316 ) in the regulator 320 decreases. However, if the voltage margin decreases below a threshold (greater than zero), the operation of the regulator 320 is impeded.
[0063] Referring to FIG. 7C , to provide the regulator 320 with a sufficient voltage margin voltage the switching frequency can be increases (and cycle time decreased), for example, to restore the margin shown in FIG. 7A . Generally, in this example, doubling the switching frequency compensates for the doubling of the output current IO. However more generally, such direct relationships between output current IO or other sensed signals and switching frequency are not necessary.
[0064] In general, a number of embodiments adapt the switching frequency of the charge pump 100 or determine the specific switching time instants based on measurements within the charge pump 100 and optionally in the low-voltage and/or high-voltage peripherals coupled to the terminals of the charge pump 100 .
[0065] In a feedback arrangement shown in FIG. 4 , the controller 350 adapts (e.g., in a closed loop or open loop arrangement) the switching frequency. For any current up to a maximum rated current with a fixed switching frequency, the charge pump 100 generally operates at a switching frequency lower than (i.e., switching times greater than) a particular minimum frequency determined by that maximum rated current. Therefore, when the current is below the maximum, capacitive losses may be reduced as compared to operating the charge pump 100 at the minimum switching frequency determined by the maximum rated current.
[0066] One approach to implementing this feedback operation is to monitor the intermediate voltage VX and adapt operation of the charge pump to maintain VMIN above a fixed minimum threshold. One way to adapt the operation of the charge pump 100 is to adapt a frequency for the switching of the charge pump 100 in a feedback configuration such that as the minimum intermediate voltage VMIN approaches the threshold, the switching frequency is increased, and as it rises above the threshold the switching frequency is reduced. One way to set the fixed minimum threshold voltage is as the maximum (e.g., rated) output voltage VO of the regulator 320 , plus a minimum desired margin above that voltage. As introduced above, the minimum margin (greater than zero) is required to allow a sufficient voltage differential (VX−VO) to charge (i.e., increase its current and thereby store energy in) the inductor 326 at a reasonable rate. The minimum margin is also related to a guarantee on a maximum duty cycle of the regulator 320 .
[0067] A second approach adapts to the desired output voltage VO of the regulator 320 . For example, the regulator 320 may have a maximum output voltage VO rating equal to 3.3 volts. With a desired minimum margin of 0.7 volts, the switching of the charge pump 100 would be controlled to keep the intermediate voltage VX above 4.0 volts. However, if the converter is actually being operated with an output voltage VO of 1.2 volts, then the switching frequency of the charge pump 100 can be reduced to the point that the intermediate voltage VX falls as low as 1.9 volts and still maintain the desired margin of 0.7 volts.
[0068] In a variant of the second approach, rather than monitoring the actual output voltage VO, an average of the voltage between the switches 312 , 314 may be used as an estimate of the output voltage VO.
[0069] In yet another variant, the switching frequency of the charge pump 100 is adapted to maintain the intermediate voltage VX below a threshold value. For example, the threshold can be set such that the intermediate voltage VX lowers or rises a specific percentage below or above the average of the intermediate voltage VX (e.g. 10%). This threshold would track the intermediate voltage VX. Similarly, a ripple relative to an absolute ripple voltage (e.g. 100 mV) can be used to determine the switching frequency.
[0070] Note also that the voltage ripple on the output voltage VO depends (not necessarily linearly) on the voltage ripple on the intermediate voltage VX, and in some examples the switching frequency of the charge pump 100 is increased to reduced the ripple on the output voltage VO to a desired value.
[0071] Other examples measure variation in internal voltages in the charge pump 100 , for example, measuring the ripple (e.g., absolute or relative to the maximum or average) across any of the capacitors C 1 through C 4 . Such ripple values can be used instead of using the ripple on the intermediate voltage VX in controlling the switching frequency of the charge pump 100 . Other internal voltages and/or currents can be used, for example, voltages across switches or other circuit elements (e.g., transistor switches), and the switching frequency can be adjusted to avoid exceeding rated voltages across the circuit elements.
[0072] In addition to the desired and/or actual output voltages or currents of the regulator 320 being provided as a control input to the controller 350 , which adapts the switching frequency of the charge pump 100 , other control inputs can also be used. One such alternative is to measure the duty cycle of the regulator 320 . Note that variation in the intermediate voltage VX affects variation in current in the Buck converters inductor 326 . For example, the average of the intermediate voltage VX is generally reduced downward with reducing of the switching frequency of the charge pump 100 . With the reduction of the average output voltage VO, the duty cycle of the regulator 320 generally increases to maintain the desired output voltage VO. Increasing the duty cycle generally increases the efficiency of a Buck converter. So reducing the switching frequency of the charge pump 100 can increase the efficiency of the regulator 320 .
[0073] It should be understood that although the various signals used to control the switching frequency may be described above separately, the switch frequency can be controlled according to a combination of multiple of the signals (e.g., a linear combination, nonlinear combination using maximum and minimum functions, etc.). In some examples, an approximation of an efficiency of the charge pump is optimized.
[0074] The discussion above focuses on using the controller 350 to adjust the switching frequency of the charge pump 100 in relatively slow scale feedback arrangement. The various signals described above as inputs to the controller 350 can be used on an asynchronous operating mode in which the times at which the charge pump 100 switches between cycles is determined according to the measurements. As one example, during state one as illustrated in FIG. 6 , the intermediate voltage VX falls, and when VX−VO reaches a threshold value (e.g., 0.7 volts), the switches in the charge pump 100 are switched together from state one to state two. Upon the transition to state two, the intermediate voltage VX rises and then again begins to fall, and when VX−VO again reaches the threshold value, the switches in the charge pump 100 are switched together from state two back to state one.
[0075] In some examples, a combination of asynchronous switching as well as limits or control on average switching frequency for the charge pump are used.
[0076] Unfortunately, as the intermediate current IX decreases the switching frequency of the charge pump 100 decreases as well. This can be problematic at low currents because the frequency could drop below 20 kHz, which is the audible limit for human hearing. Therefore, once the frequency has dropped below a certain limit, a switch 344 closes and introduces a compensation capacitor 342 . This force the converter into non-adiabatic operation allowing the frequency to be fixed to a lower bound (e.g. 20 kHz). Consequently, the compensation capacitor 342 is introduces when either the duty cycle is low or when the output current IO is low.
[0077] Note that the examples above concentrate on a compensation circuit that permits selectively switching a compensation capacitor of a certain fixed capacitance onto the output of the charge pump. More generally, a wide variety of compensation circuits can be controlled. One example is a variable capacitor, which can be implemented as a switched capacitor bank, for example, with power of two capacitances. The optimal choice of capacitance generally depends on the combination of operating conditions (e.g., average current, pulsed current duty cycle, etc.) and/or circuit configurations (e.g., type of regulators, sources, load, pump capacitors), with the determining of the desired capacitance being based on prior simulation or measurement or based on a mechanism that adjusts the capacitance, for instance, in a feedback arrangement. In addition, other forms of compensation circuits, for example, introducing inductance on the output path, networks of elements (e.g., capacitors, inductors).
[0078] Note that the description focuses on a specific example of a charge pump. Many other configurations of charge pumps, including Dickson pumps with additional stages or parallel phases, and other configurations of charge pumps (e.g., series-parallel), can be controlled according to the same approach. In addition, the peripherals at the high and/or low voltage terminals are not necessarily regulators, or necessarily maintain substantially constant current. Furthermore, the approaches described are applicable to configurations in which a high voltage supply provides energy to a low voltage load, or in which a low voltage supply provides energy to a high voltage load, or bidirectional configurations in which energy may flow in either direction between the high and the low voltage terminal of the charge pump. It should also be understood that the switching elements can be implemented in a variety of ways, including using Field Effect Transistors (FETs) or diodes, and the capacitors may be integrated into a monolithic device with the switch elements and/or may be external using discrete components. Similarly, at least some of the regulator circuit may in some examples be integrated with some or all of the charge pump in an integrated device.
[0079] Implementations of the approaches described above may be integrated into an integrated circuit that includes the switching transistors of the charge pump, either with discrete/off-chip capacitors or integrated capacitors. In other implementations, the controller that determines the switching frequency of the charge pump and/or the compensation circuit may be implemented in a different device than the charge pump. The controller can use application specific circuitry, a programmable processor/controller, or both. In the programmable case, the implementation may include software, stored in a tangible machined readable medium (e.g., ROM, etc.) that includes instructions for implementing the control procedures described above.
[0080] It is to be understood that the foregoing description is intended to illustrate and not to limit the scope of the invention, which is defined by the scope of the appended claims. Other embodiments are within the scope of the following claims.
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Cycle timing of a charge pump is adapted according to monitoring of operating characteristics of a charge pump and/or peripheral elements coupled to the charge pump. In some examples, this adaptation provides maximum or near maximum cycle times while avoiding violation of predefine constraints (e.g., operating limits) in the charge pump and/or peripheral elements.
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BACKGROUND AND SUMMARY OF THE INVENTION
The present invention relates generally to telephone switching equipment. More particularly the invention relates to a voice dialing server that attaches to the telephone branch exchange equipment to provide voice dialing services without the need to extensively modify the branch exchange equipment. The preferred system plugs into one or more unused extensions of the branch exchange system to provide voice dialing services for multiple users of the system. Each user may have his or her own dictionary of names and phone numbers. The system integrates with the existing branch exchange network, using the existing voice and control channels to cause the existing branch exchange system to perform the necessary switching operations.
Voice dialing promises to make telephones easier to use, by allowing the user to simply speak a name and then have the voice dialing system look up the telephone number of the named party and automatically place the call. In the cellular telephone market, rudimentary voice dialing systems have been experimented with to provide hands-free operation. The primary technological focus in the cellular telephone market has been on how to overcome the high ambient noise level present in the cellular telephone environment, particularly in car phone applications. There has also been some work in developing voice dialing units for the home. These units typically connect between the telephone and the outside telephone line. A primary technological focus of those units has been on how to overcome the presence of the dial tone when the user lifts the handset to use the voice dialer.
While voice dialing has made some inroads, particularly in the applications discussed above, voice dialing has yet to be incorporated into more complex telephone systems such as private branch exchange switching systems (PBX systems). There are a number of reasons for this. First, voice recognition is a challenging problem and current technology does not provide suitable recognition accuracy in an economical configuration. For example, the complex Hidden Markov Model-based systems employed by state-of-the-art speech recognizers (as in dictation transcription systems) require lots of memory and computational power.
Second, in the voice dialing application, the voice recognition problem is compounded where the system must be adapted for use by a large number of users. The need to respond to the spoken commands of a large number of users makes the voice dialing problem far more difficult than it is for simple voice dialing systems designed for home use.
Third, it is not a simple matter to integrate voice dialing into a complex telephone switching network. Modern-day telephone switching networks employ an intricate labyrinth of digital control signals that effect various switching functions (e.g. placing a call on hold, transferring a call, initiating a conference call, reassigning an extension to a different location and so forth). Simple voice dialing systems of the type employed in cellular phone applications or home dialing applications will not work in this more complex environment.
Finally, office PBX equipment is expensive and difficult to replace without disrupting day-to-day office functions. Thus many businesses that would benefit from voice dialing services, were such equipment available, simply cannot afford the cost and down-time required to replace that equipment with newer equipment providing voice dialing capabilities.
Thus, while the desirability of providing voice dialing in office systems is readily appreciated, current technology does not provide the means to accomplish it.
The present invention provides a voice dialing server for coupling to a branch exchange telephone system of the type that provides call switching among a plurality of telephone extension ports. The system is designed for plug-compatible connection to the existing telephone system without the need for modifying the system extensively. The voice dialing server has an interface for connection to at least one of the telephone extension ports of the existing telephone system. The interface supports transmission of voice signals and telephone system control information.
The voice dialing server also includes a speech processing module coupled to the interface for providing the following services. The speech processing module answers calls placed to the voice dialing server by users of the system. It processes speech input from the user, corresponding to a selected party to be called; and it looks up the telephone number of the selected party.
The voice dialing system also includes a branch exchange control module that is coupled to the interface and to the speech processing module. The control module issues control information to the telephone system, causing the telephone system to connect the user's extension to an outside line while dialing the phone number of the selected party. The preferred embodiment causes the extension that has been assigned to the interface to be connected to a second telephone port on the system. The second port can be another extension or an outside line. Then the call is placed via the second port and the user's extension is then attached to the second port. In this way the user is placed in communication with the selected party.
The system integrates fully with the existing branch exchange telephone system. Thus the invention can be readily added to an existing telephone system, simply by plugging it into an unused extension port on the system. To use the system the user simply dials the extension assigned to the voice dialing server and follows the voice prompts issued by the server. The system is preferably implemented in a multitasking environment that allows multiple threads to run concurrently. Thus multiple users may use the system simultaneously. The system is capable of providing different phone directories for different users, and these may be automatically associated with the users' telephone extension. The system is able to determine the extension of the user. By determining the user's extension the voice dialing server automatically uses the phone number dictionary created by the user at that extension. Alteratively, the user can override the determined extension by supplying a different extension, thereby causing a different phone number dictionary to be used.
Although well integrated into the existing telephone system architecture, the invention can also be used by callers outside the system to reach persons inside the system or to look up numbers from the telephone book. For example, a user calling from home may connect to the voice dialing server by specifying the server's extension. Then, the user may enter his or her office telephone extension number, thereby telling the voice dialing server that the phone number dictionary assigned to the office extension should be used. Thereafter, the user calling from home can use his or her office telephone number directory just as if the user were from the office.
The voice dialing server uses very fast and yet remarkably accurate voice recognition technology based on reliably detected phoneme similarity regions. The preferred embodiment uses a multistage word recognizer that compactly represents speech in terms of high phoneme similarity values. This is a departure from conventional techniques that determine similarity based on a frame-by-frame alignment. The preferred embodiment uses a word recognizer that preserves only the interesting regions of high phoneme similarity or features. A word recognizer is used to narrow the search so that the subsequent fine match stage is able to perform its task more quickly. The word recognizer and fine match stages share the initial representation of speech as a sequence of multiple phoneme similarity values. By representing speech as features at a lower data rate in the initial stage of recognition, the complexity of the matching procedure is greatly reduced.
For a more complete understanding of the invention, its objects and advantages, reference may be had to the following specification and to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a system block diagram showing the multiuser voice dialing server connected to an existing public branch exchange (PBX) switch;
FIG. 2 is a block diagram of a first embodiment of the invention;
FIG. 3 is a block diagram of a second embodiment of the invention;
FIG. 4 is a entity relationship diagram showing how the major software subsystems are interfaced with the existing PBX switch;
FIG. 5 is a flowchart with accompanying signal flow diagrams, showing how the PBX control functions are performed;
FIG. 6 is a phoneme similarity time series for the word "hill" spoken by two speakers;
FIG. 7 is a series of graphs showing the output of the region picking procedure whereby similarity values are converted into high similarity regions;
FIG. 8 is a block diagram of the presently preferred word recognizer system;
FIG. 9 is a block diagram illustrating the target congruence word prototype training procedure.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present voice dialing server is designed to connect to an existing telephone system of the type found in small, medium and large businesses, institutions, hotels, offices and the like. For purposes of illustrating the invention the existing telephone system will be illustrated and described as a private branch exchange system or PBX system. As will be appreciated from the following description, the invention is not limited to any particular type of telephone switching system. Hence the reference to private branch exchange or PBX systems in this written description is not intended to limit the invention.
With the foregoing in mind, FIG. 1 depicts a conventional PBX switch 10 to which a plurality of telephone stations 12 are connected. PBX switch 10 is connected through a plurality of outside lines 14 to the telephone network infrastructure 16. Each of the individual stations 12 is connected to a separate extension or port, assigned a unique extension number. When calling internally from one station to another, the extension numbers may be dialed directly and the PBX switch connects the calling station to the designated receiving station. When placing calls to the telephone network 16 the full telephone number of the intended receiving station is dialed through the PBX switch.
The multiuser voice dialing server 18 of the invention is connected to one or more extension ports of the PBX switch 10, essentially in the same fashion as telephone stations 12 are connected. Preferably the voice dialing server is assigned an extension number different from the extension numbers assigned to the telephone stations 12. In this example the voice dialing server is assigned extension number #100. Although it is possible to implement the invention using only one extension line, the voice dialing server will handle more traffic from users if the server is connected through a plurality of lines to the PBX switch. In FIG. 1 server 18 is connected through three separate lines 20 to three separate extension ports of the PBX switch 10. These lines may be referred to as the voice dialing lines, although it will be appreciated that these lines are physically the same as the telephone station lines 22 that connect the telephone stations 12 to the PBX switch.
When multiple voice dialing lines are used, as illustrated here, one line will be assigned the primary extension number (in this case #100). The remaining lines are assigned other extension numbers. To make the system easy to use, the PBX switch 10 is programmed so that the primary extension (#100) is used by all users. When this extension is busy (in use by an earlier user) subsequent calls to the primary extension are routed to one of the unused remaining lines. If all voice dialing lines are busy when a user attempts to employ the voice dialing server, a busy signal will be received. This does not ordinarily occur because the voice dialing server is designed to drop out of the communication path once the desired number has been dialed. The system is designed to prompt the user for a name. It then looks up the telephone number associated with that name and dials it after receiving verbal confirmation from the user. The voice recognizer of the preferred embodiment is quite fast, hence each individual use of the system does not tie up a voice dialing extension for very long.
A first embodiment of the voice dialing server is illustrated in FIG. 2. In FIG. 2 PBX switch 10 and the voice dialing lines 20 have been illustrated. The remaining components of the telephone system, as shown in FIG. 1, have been omitted from FIG. 2 to simplify the illustration. The voice dialing server can be implemented using a conventional personal computer, depicted diagrammatically at 28, that has been equipped with the voice dialing server software described more fully below. The voice dialing server embodiment of FIG. 2 uses an analog interface 30 that plugs into the PC bus 32 and has ports for connecting to voice dialing lines 20. An optional digital interface 34 may be connected through a plurality of RS-232 lines 36 to the serial ports 38 of computer 28. In this case there would be a digital line for each analog line. The digital interface is connected in parallel with the analog interface to the voice dialing lines 20. Computer 28 includes a central processing unit 40 and random access memory 42. These are coupled to PC bus 32 in conventional fashion. A disk drive 44 is used to store the multiuser phone number dictionaries, as well as the boot copy of the voice dialing server software. The voice dialing server software is loaded into RAM 42, where it is accessed by the CPU 40 during execution. Disk drive 44 may be coupled through any suitable interface such as a SCSI interface 46 to the PC bus 32.
The analog interface of this embodiment may be a model D41E voice board available from Dialogic. Analog interface 30 includes a digital signal processor (DSP) and a general purpose microprocessor. The interface is capable of handling all telephony signal and it performs DTMF (touchtone) detection and generation as well as audio/voice signal processing tasks. The D41E voice board from Dialogic supports four independent voice channels.
The digital interface 34 is a protocol converter that converts the digital control signals from PBX switch 10 into serial signals conforming to the telephony application programming interface (TAPI) protocol established by Microsoft Corporation. The digital interface 34 is optional. Essentially, it is provided to allow the voice dialing server to determine the user's extension number automatically. The TAPI protocol is used to employ a caller ID function that will tell the voice dialing server what extension the user is calling from. Knowing this extension allows the voice dialing server to automatically use the phone number dictionary that is preassigned to that caller's extension. Without the caller ID information, the voice dialing server will need to prompt the user to enter his or her extension in order to activate the correct phone number dictionary.
An alternate embodiment of the invention is depicted in FIG. 3. The embodiment of FIG. 3 is similar to that of FIG. 2 except that a dedicated digital interface 35 is used in place of analog interface 30 and digital interface 34. The dedicated digital interface is designed to directly connect with a predetermined make and model of PBX switch. The availability of such a dedicated digital interface 35 depends on the make and model of the PBX system. One such system is a Norstar PBX switch using a D/42-NS voice board as digital interface 35. The D/42-NS voice board is available from Dialogic. It functions similar to the D41E analog voice board described above, with additional digital control features built-in to interface with the Norstar PBX switch.
As noted above, the presently preferred embodiments are implemented using a suitably programmed personal computer. FIG. 4 is a software entity relationship diagram showing the preferred software architecture that may be used to program the computer. Essentially, the software performs two functions: a voice interaction function and a PBX control function. From a voice and control signal standpoint, all communication with the PBX switch 10 is through an interface 60. The interface 60 supports both bidirectional voice communication and digital control information. The software of the preferred embodiment assumes that the voice channel has been digitized, hence the voice information communicated through interface 60 is digital audio data. If analog voice signals are present in the PBX system, they may be converted into digital signals through the analog interface hardware 30 (FIG. 2).
Connected to interface 60 is the kernel module 62 that oversees the operation of the server software. Attached to the kernel module 62 is the voice recognizer module 64 and speech synthesis module 66. The voice recognizer 64 works with a multiuser phone book dictionary 68 that contains all of the multiple users' personal phone book information, that is, the names and phone numbers that the users have entered by speaking the names and entering the numbers using DTMF tones entered through the touchtone keypad of the station handset. A subset of kernel module 62 are the PBX control functions 70. These are a stored set of digital control commands that cause the PBX 10 to execute certain control functions, in effect mimicking the control functions that a user of a telephone station handset might employ. The PBX control functions include the ability to place a call on hold and to request the PBX switch to set up a conference call. These commands are used during dialing of the selected phone number and thereafter to connect the user to the selected party. See pseudocode in the Appendix for details.
FIG. 5 is a flowchart showing how a user (at extension #214) might use the voice dialing server (at extension #100) to place an outside call using the voice dialer dictionary. Alongside the numbered boxes of the flowchart several reproductions of FIG. 1 have been illustrated, showing in bold lines how the switching actually occurs. The reader may wish to refer to these switching diagrams while reading the flowchart of FIG. 5.
The procedure begins at Step 90. The user at extension #214 lifts the handset of the telephone station and dials the extension of the voice dialing server (#100). The server answers the call and prompts the user for a name at Step 92. To effect this step the analog interface 30 (FIG. 2) or the dedicated digital interface 35 (FIG. 3) detects the ring signal and answers the incoming call. The extension number of the user's station is detected at this point for use in selecting the proper dictionary. The user may override by entering a different extension number. The incoming call event is transmitted through interface 60 (FIG. 4) to the kernel module 62. In response, the kernel module 62 employs the speech synthesis module 66 to prompt the user for a name and then monitors the voice channel (through interface 60) while employing the recognizer module 64.
Returning to FIG. 5, when the server recognizes the name spoken by the caller at Step 94, the server looks up the phone number to dial using the multiuser phone book dictionary 68 (FIG. 4). If the voice recognizer does not identify a name in the dictionary, or if the recognized name is below a predetermined reliability threshold the kernel module 62 may employs the speech synthesis module 66 to prompt the user to try again.
After recognizing the name and looking up the phone number, the kernel module 62 of the server prompts the user by repeating the name and asking the user to verify that the name is correct. The user may then either answer yes or no. If the answer is yes, the server will proceed to place the call. If the answer is no, the server will prompt the user to try again.
During these first three steps (Steps 90-94) the user's extension is connected through the PBX switch to the voice dialing server. This is shown in the switching diagram adjacent Steps 90-94. Bold lines are used to show the connection.
After obtaining the number to call and receiving the user's verification, the server then at Step 96 temporarily places the user on hold or in conference call mode. Then in Step 98 the server places a call through the PBX switch to the phone number that was determined during the lookup procedure. As illustrated at B the user's extension (#214) is temporarily placed on hold while the server is connected to an outside line via the PBX switch. Note that this technique allows the voice dialing server to connect to an outside line without the need to employ a separate inside extension. To effect this operation the kernel module 62 uses one of the PBX control functions 70 to send a request through interface 60 to the PBX. The request causes the PBX to place the user's extension on hold or in conference call mode and then causes the PBX switch to connect the server's extension (#100) to an outside line. This is done by mimicking the control signal commands that would be sent by a user of a telephone station handset to effect these same functions.
After establishing an outside line connection and receiving a dial tone, the server places the call by dialing the number that was looked up. The kernel 62 performs this operation by using the DTMF dialing capabilities of the analog interface 30 (FIG. 2) or the digital interface 35 (FIG. 3).
After dialing the desired number the server causes the PBX switch to conference in the user's extension at Step 100. As shown at C, the user's extension (#214) and the voice dialing server's extension (#100) are now both connected through a conference call to the outside line. Finally, in Step 102 the server drops out of the communication as illustrated at D. This leaves the user's extension (#214) connected to the outside line and frees up the server for its next use by another user.
The present invention employs a unique compact speech representation based on regions of high phoneme similarity values. As shown in FIG. 6, there is an overall consistency in the shape of the phoneme similarity time series for a given word. In FIG. 6 phoneme similarity time series for the word "hill" spoken by two speakers are compared. Although the precise wave shapes differ between the two speakers, the phoneme similarity data nevertheless exhibit regions of similarity between the speakers. Similar behavior is observed in the phoneme plausibility time series that has been described by Gong and Haton in "Plausibility Functions in Continuous Speech Recognition: The VINICS System," Speech Communication, Vol. 13, October 1993, pp. 187-196.
Conventional speech recognition systems match each input utterance to reference templates, such as templates composed on phoneme similarity vectors, as in the model speech method (MSM) of Hoshimi et al., "Speaker-Independent Speech Recognition Method Using Training Speech From a Small Number of Speakers," ICASSP, Vol. 1, pp. 469-472, 1992. In these conventional systems the reference speech representation is frame-based and requires a high data rate, typically 8 to 12 parameters every 10 to 20 milliseconds. The frame-by-frame alignment that is required with these conventional systems is computationally costly and makes this approach unsuitable for larger vocabularies, especially when using small hardware.
The present system uses a multistage word recognizer that is applied prior to a frame-by-frame alignment, in order to reduce the search space and to achieve real time performance improvements. The number of stages in the recognizer, as well as the computational complexity of each stage and the number of word candidates preserved at each stage, can be adjusted to achieve desired goals of speed, memory size and recognition accuracy for a particular application. The word recognizer uses an initial representation of speech as a sequence of multiple phoneme similarity values. However, the word recognizer further refines this speech representation to preserve only the interesting regions of high phoneme similarity. Referring to FIG. 7, the interesting regions of high phoneme similarity value are represented as high similarity regions. By representing the speech as features at a lower data rate in the initial stages of recognition, the complexity of the matching procedure is greatly reduced.
The multistage word recognizer also employs a unique scoring procedure for propagating and combining the scores obtained at each stage of the word recognizer in order to produce a final word decision. By combining the quasi-independent sources of information produced at each stage, a significant gain in accuracy is obtained.
The system's architecture features three distinct components that are applied in sequence on the incoming speech to compute the best word candidate.
Referring to FIG. 8, an overview of the presently preferred system will be presented. The first component of the present system is a phoneme similarity front end 110 that converts speech signals into phoneme similarity time series. Speech is digitized at 8 kilohertz and processed by 10th order linear predictive coding (LPC) analysis to produce 10 cepstral coefficients every 100th of a second. Each block of 10 successive frames of cepstral coefficients is compared to 55 phoneme reference templates (a subset of the TIMIT phoneme units) to compute a vector of multiple phoneme similarity values. The block of analysis frames is then shifted by one frame at a time to produce a vector of phoneme similarity values each centisecond (each 100th of a second). As illustrated in FIG. 8, the phoneme similarity front end works in conjunction with a phone model database 112 that supplies the phoneme reference templates. The output of the phoneme similarity front end may be stored in a suitable memory for conveying the set of phoneme similarity time series so generated to the word recognizer stages.
The word recognizer stages, depicted in FIG. 8 generally at 114, comprise the second major component of the system. A peak driven procedure is first applied on the phoneme similarity time series supplied by front end 110. The peak driven procedure extracts High Similarity Regions (HS Regions). In this process, low peaks and local peaks of phoneme similarity values are discarded, as illustrated in FIG. 7. In the preferred embodiment regions are characterized by 4 parameters: phoneme symbol, height at the peak location and time locations of the left and right frames. Over our data corpus, an average of 60 regions per second of speech is observed. In FIG. 8 the high similarity region extraction module 116 performs the peak driven procedure. The output of the HS region extraction module is supplied to two different word recognizer stages that operate using different recognizer techniques to provide a short list of word candidates for the fine match final recognizer stage 126.
The first of the two stages of word recognizer 114 is the Region Count stage or RC stage 118. This stage extracts a short list of word candidates that are then supplied to the next stage of the word recognizer 114, the Target Congruence stage or TC stage 120. The RC stage 118 has an RC word prototype database 122 that supplies compact word representations based on the novel compact speech representation (regions of high phoneme similarity values) of the invention. Similarly, the TC stage 120 also includes a TC word prototype database 124 that supplies a different compact word representation, also based on the compact speech representation of the invention. The TC stage provides a more selective short list of word candidates, essentially a further refinement of the list produced by the RC stage 118.
The word decision stage 126, the final major component of the present system, selects the word with the largest score from the short list supplied by TC stage 120.
Region Count Modeling
The RC stage 118 of word recognizer 114 represents each reference word with statistical information on the number of HS regions over a predefined number of time intervals. The presently preferred embodiment divides words into three equal time intervals in which each phoneme interval is described by (1) the mean of the number of HS regions occurring in that interval and (2) a weight that is inversely proportional to the square of the variance, which indicates how reliable the region count is. Specifically for a score normalized between 0 and 100, the weight would be 100/(variance 2 +2). These parameters are easily estimated from training data. In the currently preferred implementation, each word requires exactly 330 parameters, which corresponds to two statistics, each over three intervals each comprising 55 phoneme units (2 statistics×3 intervals×55 phoneme units).
Region count modeling was found to be very effective due to its fast alignment time (0.33 milliseconds per test word on a Sparc10 workstation) and its high top 10% accuracy.
The region count prototype is constructed as follows. A first utterance of a training word or phrase is represented as time-dependent phoneme similarity data. In the presently preferred embodiment each utterance is divided into N time intervals. Presently each utterance is divided into three time intervals, with each time interval being represented by data corresponding to the 55 phonemes. Thus the presently preferred implementation represents each utterance as a 3×55 vector. In representing the utterance as a 3×55 vector, each vector element in a given interval stores the number of similarity regions that are detected for each given phoneme. Thus if three occurrences of the phoneme "ah" occur in the first interval, the number 3 is stored in the vector element corresponding to the "ah" phoneme.
An inductive or iterative process is then performed for each of the successive utterances of the training word or phrase. Specifically, each successive utterance is represented as a vector like that of the first utterance. The two vectors are then combined to generate the vector sum and the vector sum of the squares. In addition, a scalar count value is maintained to keep track of the current number of utterances that have been combined.
The process proceeds inductively or iteratively in this fashion, each new utterance being combined with the previous ones such that the sum and sum of squares vectors ultimately represent the accumulated data from all of the utterances.
Once all training utterances have been processed in this fashion the vector mean and vector variance are calculated. The mean vector is calculated as the sum vector divided by the number of utterances used in the training set. The vector variance is the mean of the squares minus the square of the means. The mean and variance vectors are then stored as the region count prototype for the given word or phrase. The same procedure is followed to similarly produce a mean and variance vector for each of the remaining words or phrases in the lexicon.
When a test utterance is compared with the RC prototype, the test utterance is converted into the time dependent phoneme similarity vector, essentially in the same way as each of the training utterances were converted. The Euclidean distance between the test utterance and the prototype is computed by subtracting the test utterance RC data vector from the prototype mean vector and this difference is then squared. The Euclidean distance is then multiplied by a weighting factor, preferably the reciprocal of the prototype variance. The weighted Euclidean distance, so calculated, is then converted into a scalar number by adding each of the vector component elements. In a similar fashion the weighting factor (reciprocal of the variance) is converted into a scalar number by adding all of the vector elements. The final score is then computed by dividing the scalar distance by the scalar weight.
The above process may be repeated for each word in the prototype lexicon and the most probable word candidates are then selected based on the scalar score.
Target Congruence Modeling
The second stage of the word recognizer represents each reference word by (1) a prototype which consists of a series of phoneme targets and (2) by global statistics, namely the average word duration and the average "match rate," which represents the degree of fit of the word prototype to its training data. In the presently preferred embodiment targets are generalized HS regions described by 5 parameters:
1. phoneme symbol;
2. target weight (percentage occurrence in training data);
3. average peak height (phoneme similarity value);
4. average left frame location;
5. average right frame location.
Word prototypes are automatically created from the training data as follows. First, HS regions are extracted from the phoneme similarity time series for a number of training speakers. The training data may be generated based on speech from a plurality of different speakers or it may be based on multiple utterances of the same training words by a single speaker. Then, for each training utterance of a word, reliable HS regions are computed by aligning the given training utterance with all other utterances of the same word in the training data. This achieves region-to-region alignment.
For each training utterance the number of occurrences (or probability) of a particular region is then obtained. At that time, regions with probabilities less than a pre-established Reliability Threshold (typically 0.25) are found unreliable and are eliminated. The word prototype is constructed by merging reliably detected, high similarity regions to form targets. At the end of that process a target rate constraint (i.e. desired number of targets per second) is then applied to obtain a uniform word description level for all the words in the lexicon. The desired number of targets per second can be selected to meet system design constraints such as the ability of a given processor to handle data at a given rate. By controlling the target rate a reduction in the number of targets is achieved by keeping only the most reliable targets. Once the word prototype has been obtained in this fashion, the average match rate and average word duration are computed and stored as part of the word prototype data.
The number of parameters needed to represent a word depends on the average duration of the word and on the level of phonetic detail that is desired. For a typical 500 millisecond word at 50 targets per second, the speech representation used by the presently preferred embodiment employs 127 parameters, which correspond to 5 values per target×50 targets per second×0.5 seconds+2 global statistics (average match rate and average word duration).
FIG. 9 illustrates the word prototype training procedure by which the TC word prototype database 124 is constructed. The RC word prototype database 122 is constructed by similar, but far simpler process, in that only the presence or absence of an HS region occurring with each of the three equal time intervals must be detected.
Referring to FIG. 9, the HS Region Computation Module 116 is used to convert the similarity time series from the speech database into a list of HS regions. The alignment module 130 operates on this list of HS regions to eliminate unreliable regions by alignment across speakers. Again, the process can be performed across a plurality of different speakers or across a plurality of utterances by the same speaker.
Next the list of reliable regions, together with the associated probabilities of detecting those regions is passed to the target building module 132. This module builds targets by unifying the region series to produce a list of phoneme targets associated with each word in the database. This list of phoneme targets is then supplied to a module 134 that adjusts the target rate by applying the target rate constraint. The target rate constraint (the desired number of targets per second) may be set to a level that achieves the desired target rate. After adjusting the target rate a statistical analyzer module 136 estimates the global statistics (the average match rate and the average word duration) and these statistics along with the list of targets at the selected rate are then stored as the TC word prototype database 124.
Word Recognition
Given an active lexicon of N words, the region count stage is first applied to produce a short list of word candidates with normalized scores. A weighted Euclidean distance is used to measure the degree of fit of a test word X to a reference word P (in RC format as supplied by the RC word prototype database). Specifically, in the current implementation the weighted Euclidean distance is defined as ##EQU1## where x ij is the number of HS regions in time interval I for phoneme j, where p ij is the corresponding average number of HS regions estimated on training data, and where w ij is the corresponding weight. The N/10 highest scoring word prototypes are preserved as word candidates and their scores (weighted Euclidean distances) are normalized by dividing each individual score by the highest score. This defines a normalized score S RC for each word. Normalized scores range from 0 to 1 and are dimensionless, making it possible to combine scores resulting from different scoring methods.
The target congruence stage is then applied on each word candidate selected by the RC stage. A region-to-target alignment procedure is used to produce a congruence score between the test word and a given word reference (in TC format as supplied by the TC word prototype database). The congruence score of a matched target CGmatch, that is, the alignment found between target t of the prototype and region r of the test word, is defined as
CG.sub.match (t,r)=min(A.sub.t |A.sub.r,A.sub.r |A.sub.t)
where A t and A r respectively represent the target's area and the aligned region's area in the time similarity plane.
The congruence score of an unmatched target CGunmatch is computed in the same way, using an estimate for the area A r of the missing HS region. The estimated area A r is computed as the area under the similarity curve for the target's phoneme label, between the projected locations of the target's left and right frames.
The word congruence score is computed as the weighted sum of congruence scores for all the targets, divided by the sum of their weights. Normalized congruence scores STC are computed by dividing the individual congruence scores by the highest congruence score. The final score output by the word recognizer is a combination of the information obtained at each recognizer stage. In the presently preferred embodiment the final score output of the recognizer is:
S.sub.Hypo =(S.sub.RC +S.sub.TC)/2
The recognized word is the one with the highest S Hypo value.
______________________________________APPENDIX______________________________________Notes:The function TransferCallDesklab(Number) does the transfer to an insideextension by calling the PBX function "feature 7 0" followed by theextension number after a hookflash. Then the line is released.The function TransferExternalCallDeskLab(Number) does the transferoutside. In the program a message is played, then the user is put onhold (by sending "feature 7 9", then the program gets an external line,then a conference call is established, the phone number is dialed, andtheline is released.Pseudocode:int TransferCallDeskLab(Number)char *Number;int LastRet;int Ret;ghookflash((*DskLab).Desc,500);gdial((*DskLab).Desc,"*70",1);gdial((*DskLab).Desc,Number,1);gphone.sub.-- hookswitch((*DskLab).Desc,1);while (Ret=gphone.sub.-- status((*DSkLab).Desc,&LastRet)|=G.sub.-- ONHOOK){sleep(1);}}int TransferExternalCallDeskLab (phoneNumber)char *phoneNumber;{int LastRet;int Ret;int lastatus=-199, rtnval;int thereIsProblem,state,new.sub.-- state, last.sub.-- state;extern char *G.sub.-- PhoneStatus !;char msg ! = "Calling";/* Play message while transfering */ALIPlayMessage(msg);esleep(1,1000);printf("Putting calling line on hold . . .");fflush(stdout);ghookflash((*DskLab).Desc,500);gdial((*DskLab).Desc,"*79",1);printf("done|\n"); fflush(stdout);printf("Getting external line . . . "); fflush(stdout);gdial((*DskLab).Desc,"9",0); /* obtain an external line */state = 0;do {esleep(0,1000);new.sub.-- state = gphone.sub.-- status((*DskLab).Desc,&last.sub.--state);if (state |= new.sub.-- state) { state = new.sub.-- state; printf("state = %s\n",G.sub.-- PhoneStatus state!);}thereIsProblem = 0;switch (state) {case G.sub.-- ONHOOK: /* call disconnected -- strangely */case G.sub.-- BUSY: /* cannot get an outside line */case G.sub.-- REORDER:case G.sub.-- REORDER2: thereIsProblem = 1;default: break;}} while ( (state |= G.sub.-- DIALTONE ) &&(state |= G.sub.-- CONNECTED) && |thereIsProblem );printf("done|\n"); fflush(stdout);printf("Establishing Conference Call . . .");fflush(stdout);ghookflash((*DskLab).Desc,500); gdial((*DskLab).Desc,"*3",1);ALIPlayMessage(msg);printf("Dialing %s . . .", phoneNumber); fflush(stdout);gdial((*DskLab).Desc,phoneNumber,1);printf("done|\n"); fflush(stdout);state = 0;do {esleep(0,10000); /* 1/4 second sleep */new.sub.-- state = gphone.sub.-- status((*DskLab).Desc,&last.sub.--state);if (state |= new.sub.-- state) { state = new.sub.-- state; printf("state = %s\n",G.sub.-- PhoneStatus state!);fflush(stdout);}thereIsProblem = 0;switch (state) {case G.sub.-- ONHOOK: /* call disconnected -- strangely */case G.sub.-- BUSY: /* cannot get an outside line */case G.sub.-- REORDER:case G.sub.-- REORDER2: thereIsProblem = 1;default: ;}} while ((state |=G.sub.-- CONNECTED ) && (state |= G.sub.-- BUSY) &&|thereIsProblem);printf("Putting phone ONHOOK . . .");fflush(stdout);gphone.sub.-- hookswitch((*DskLab).Desc,G.sub.-- ONHOOK);while ((Ret=gphone.sub.-- status((*DskLab).Desc,&LastRet))|=G.sub.-- ONHOOK){sleep(1);}printf("done|\n"); fflush(stdout);}______________________________________
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The voice dialing server plugs into one or more unused extensions of a branch exchange system to provide each of the users on the system with voice dialing services. To use the system a user simply dials the extension to which the server is attached. The server then prompts the user to supply the name of a party to be called. The name is then looked up in a telephone number dictionary unique to that user. The system then places the telephone call by sending commands to the branch exchange system that simulate the operations a user would perform to connect to an outside line or inside extension and then place the call. The server incorporates a speech processing module having a multistage word recognizer that represents speech in terms of high phoneme similarity values. This representation is highly compact, allowing the word recognizer to perform the recognizer and fine match stages with far less processor overhead than frame-by-frame speech recognizers.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a flow control valve. More particularly, the present invention relates to a flow control valve for controlling the oil pressure applied to a hydraulic actuator.
[0003] 2. Description of the Related Art
[0004] A forklift for driving a fork that holds a load by using oil pressure has been well known. The forklift includes a lift cylinder for driving the fork that holds a load along with a flow control valve. FIG. 1 is a schematic view showing the conventional flow control valve. The flow control valve 101 includes a direction switching valve 102 and a check valve 103 . The flow control valve 101 further includes a plurality of lines for guiding hydraulic oil to transmit oil pressure. The plurality of lines is composed of a pump pressure line 111 , a pump pressure line 112 , a load pressure line 113 and a drain line 115 .
[0005] The pump pressure line 111 connects the direction switching valve 102 to a pump not shown and leads hydraulic oil supplied by the pump. The pump pressure line 112 connects a check valve 103 to the direction switching valve 102 . The load pressure line 113 connects the check valve 103 , the lift cylinder 104 and the direction switching valve 102 . The drain line 115 connects the direction switching valve 102 to a tank 106 and the oil pressure of the drain line 115 is substantially zero (0).
[0006] The check valve 103 prevents hydraulic oil from flowing from the load pressure line 113 to the pump pressure line 112 . That is, the check valve 103 connects the pump pressure line 112 to the load pressure line 113 when the oil pressure of the pump pressure line 112 is larger than that of the load pressure line 113 , and does not connect the pump pressure line 112 to the load pressure line 113 when the oil pressure of the load pressure line 113 is larger than that of the pump pressure line 112 .
[0007] The lift cylinder 104 is an actuator for lifting and lowering the fork of the forklift. That is, the lift cylinder 104 lifts the fork of the forklift when hydraulic oil is supplied from the load pressure line 113 and lowers the fork of the forklift when hydraulic oil is discharged into the load pressure line 113 . At this time, the oil pressure of the load pressure line 113 varies depending on the weight of a load held by the fork of the forklift and becomes larger as the load is heavier.
[0008] The direction switching valve 102 can occupy one of a neutral position, a meter-in position and a meter-out position. That is, operated by the user, the direction switching valve 102 is switched from the neutral position to the meter-in position, from the neutral position to the meter-out position, from the meter-in position to the neutral position and from the meter-out position to the neutral position.
[0009] At the meter-in position, the direction switching valve 102 connects the pump pressure line 111 to the pump pressure line 112 , closes the load pressure line 113 and closes the drain line 115 . At the meter-out position, the direction switching valve 102 closes the pump pressure line 111 , closes the pump pressure line 112 and connects the load pressure line 113 to the drain line 115 . At the neutral position, the direction switching valve 102 closes the pump pressure line 111 , closes the pump pressure line 112 , closes the load pressure line 113 and closes the drain line 115 .
[0010] The tank 106 stores hydraulic oil flowing through the drain line 115 therein. The hydraulic oil stored in the tank 106 is supplied to the pump pressure line 111 by a pump not shown.
[0011] Operations of the flow control valve 101 include a meter-in operation, a neutral operation and a meter-out operation. The meter-in operation is an operation performed when the direction switching valve 102 is switched from the neutral position to the meter-in position by means of the user's operation. The neutral operation is an operation performed when the direction switching valve 102 is switched from the meter-in position or the meter-out position to the neutral position by means of the user's operation. The meter-out operation is an operation performed when the direction switching valve 102 is switched from the neutral position to the meter-out position by means of the user's operation.
[0012] In the meter-in operation, hydraulic oil is supplied from the pump pressure line 111 to the lift cylinder 104 through the direction switching valve 102 , the pump pressure line 112 , the check valve 103 and the load pressure line 113 . When the hydraulic oil is supplied, the lift cylinder 104 lifts the fork.
[0013] In the neutral operation, since the switching valve 102 closes connection between the pump pressure line 111 and the pump pressure line 112 and between the load pressure line 113 and the drain line 115 , no hydraulic oil of the lift cylinder 104 is supplied or discharged and thus lifting or lowering of the fork is stopped. At this time, the load pressure varies depending on a load held by the fork of the forklift and becomes larger as the load is heavier.
[0014] In the meter-out operation, hydraulic oil is discharged from the lift cylinder 104 to the drain line 115 through the load pressure line 113 and the direction switching line 102 . When the hydraulic oil is discharged, the lift cylinder 104 lowers the fork.
[0015] Even when the operation quantity of the direction switching valve 102 is identical, the higher the oil pressure of the load pressure line 113 is, the higher the hydraulic oil flows from the load pressure line 113 to the drain line 115 . That is, in the forklift to which the flow control valve 101 is applied, even with the same operation quantity, the heavier the held load is, the faster the folk is lowered. A forklift with a fork having high operability has been desired.
[0016] In conjunction with the above description, Japanese Laid-Open Patent Application JP-A-Heisei, 08-100804 discloses a pressure compensating valve which only varies a set pressure of a relief valve without exchanging a piston, etc. The pressure compensating valve is characterized by including: a valve for opening and closing an inlet port and an outlet port; a piston for pressing the valve in the closing direction with a load pressure within a pressure chamber; an intermediate pressure chamber connected to the inlet port through a small cavity for pressing the valve in the closing direction; and a variable set pressure relief valve for relieving pressure oil in the intermediate pressure chamber to the outlet port through the small cavity.
SUMMARY OF THE INVENTION
[0017] An object of the present invention is to provide a flow control valve which improves operability of a hydraulic actuator.
[0018] Another object of the present invention is to provide a flow control valve which reduces the influence of a load of a hydraulic actuator.
[0019] Still another object of the present invention is to provide a flow control valve which reduces hunting of the operation of a hydraulic actuator.
[0020] Yet still another object of the present invention is to provide a flow control valve which reduces shock of the operation of a hydraulic actuator.
[0021] It is also an object of the present invention to provide a forklift which improves operability of a fork.
[0022] This and other objects, features and advantages of the present invention will be readily ascertained by referring to the following description and drawings.
[0023] In order to achieve an aspect of the present invention, the present invention provides a flow control valve comprising a pressure compensating valve and a first switching valve. The pressure compensating valve is configured to enlarge an opening area of a variable orifice between a load pressure line and a compensating pressure line when a pressure of working fluid of said compensating pressure line is smaller than a first set pressure, and narrow said opening area of said variable orifice when said pressure of said working fluid of said compensating pressure line is larger than said first set pressure. The first switching valve is configured to switch between a meter-out operation and a neutral operation by an external operation, wherein said working fluid of said compensating pressure line is drained in said meter-out operation, said working fluid of said compensating pressure line is not drained in said neutral operation. Said load pressure line guides said working fluid to be supplied to an actuator.
[0024] The flow control valve may further comprises a relief valve configured to drain said working fluid of said compensating pressure line when said pressure of said working fluid of said compensating pressure line is larger than a second set pressure, and configured not to drain said working fluid of said compensating pressure line when said pressure of said working fluid of said compensating pressure line is smaller than said second set pressure.
[0025] In the flow control valve, said first switching valve may switch among a meter-in operation, a meter-out operation and a neutral operation by an external operation. Working fluid may be supplied to said load pressure line in said meter-in operation for operating said actuator.
[0026] In the flow control valve, said relief valve may not be connected to said compensating pressure line when said first switching valve is in said meter-in operation.
[0027] In the flow control valve, said first switching valve may include a first spool chamber and a first spool configured to be slidably inserted into said first spool chamber. Said relief valve may include a second spool chamber configured to be formed in said first spool and a second spool configured to be slidably inserted into said second spool chamber.
[0028] The flow control valve may further comprise a second switching valve configured to connect said compensating pressure line to said relief valve when said first switching valve is in said neutral operation and said meter-out operation, and configured not to connect said compensating pressure line to said relief valve when said first switching valve is in said meter-in operation.
[0029] In the flow control valve, said first switching valve may switch among a meter-in operation, a meter-out operation and a neutral operation by an external operation. Working fluid may be supplied to said load pressure line in said meter-in operation for operating said actuator.
[0030] In order to achieve another aspect of the present invention, the present invention provides a forklift comprising a flow control valve, a fork configured to lift a load and an actuator configured to be connected between said flow control valve and said fork. Said flow control valve includes a pressure compensating valve and a first switching valve. The pressure compensating valve is configured to enlarge an opening area of a variable orifice between a load pressure line and a compensating pressure line when a pressure of working fluid of said compensating pressure line is smaller than a first set pressure, and narrow said opening area of said variable orifice when said pressure of said working fluid of said compensating pressure line is larger than said first set pressure. The first switching valve is configured to switch between a meter-out operation and a neutral operation by an external operation, wherein said working fluid of said compensating pressure line is drained in said meter-out operation, said working fluid of said compensating pressure line is not drained in said neutral operation. The load pressure line guides said working fluid to be supplied to said actuator.
[0031] In the forklift, said flow control valve may further include a relief valve configured to drain said working fluid of said compensating pressure line when said pressure of said working fluid of said compensating pressure line is larger than a second set pressure, and configured not to drain said working fluid of said compensating pressure line when said pressure of said working fluid of said compensating pressure line is smaller than said second set pressure.
[0032] In the forklift, said first switching valve may switch among a meter-in operation, a meter-out operation and a neutral operation by an external operation. Working fluid is supplied to said load pressure line in said meter-in operation for operating said actuator.
[0033] In the forklift, said relief valve may not be connected to said compensating pressure line when said first switching valve is in said meter-in operation.
[0034] In the forklift, said first switching valve includes a first spool chamber and a first spool configured to be slidably inserted into said first spool chamber. Said relief valve includes a second spool chamber configured to be formed in said first spool and a second spool configured to be slidably inserted into said second spool chamber.
[0035] In the forklift, said flow control valve further includes a second switching valve configured to connect said compensating pressure line to said relief valve when said first switching valve is in said neutral operation and said meter-out operation, and configured not to connect said compensating pressure line to said relief valve when said first switching valve is in said meter-in operation.
[0036] In the forklift, said first switching valve switches among a meter-in operation, a meter-out operation and a neutral operation by an external operation, wherein working fluid is supplied to said load pressure line in said meter-in operation for operating said actuator.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] FIG. 1 is a schematic view showing the conventional flow control valve;
[0038] FIG. 2 is a schematic view showing the flow control valve of the present invention;
[0039] FIG. 3 is a cross sectional view showing the flow control valve main unit including the flow control valve 1 ;
[0040] FIG. 4 is a schematic view showing another embodiment of a flow control valve according to the present invention;
[0041] FIG. 5 is a schematic view showing still another embodiment of a flow control valve according to the present invention; and
[0042] FIG. 6 is a schematic perspective view showing the forklift with the flow control valve of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0043] An embodiment of a forklift according to the present invention will be described below with reference to attached drawings. The forklift includes a lift cylinder for driving a folk that holds a load along with a flow control valve. FIG. 2 is a schematic view showing the flow control valve of the present invention. As shown in FIG. 2 , the flow control valve 1 includes a direction switching valve 2 , a check valve 3 and a pressure compensating valve 5 . The flow control valve 1 further includes a plurality of lines for guiding hydraulic oil to transmit oil pressure. The plurality of lines is composed of a pump pressure line 11 , a pump pressure line 12 , a load pressure line 13 , a compensating pressure line 14 and a drain line 15 .
[0044] The pump pressure line 11 connects the direction switching line 2 to a pump not shown and guides hydraulic oil supplied by the pump. The pump pressure line 12 connects the direction switching valve 2 to the check valve 3 . The load pressure line 13 connects between the check valve 3 , the lift cylinder 4 and the pressure compensating valve 5 . The compensating pressure line 14 connects the pressure compensating valve 5 to the direction switching valve 2 . The drain line 15 connects the direction switching valve 2 to a tank 6 and the oil pressure of the drain line 15 is substantially zero (0). The check valve 3 prevents hydraulic oil from flowing from the load pressure line 13 to the pump pressure line 12 . That is, the check valve 3 connects the pump pressure line 12 to the load pressure line 13 when the oil pressure of the pump pressure line 12 is larger than that of the load pressure line 13 , and the check valve 3 does not connect the pump pressure line 12 to the load pressure line 13 when the oil pressure of the load pressure line 13 is larger than that of the pump pressure line 12 . The check valve 3 may be omitted from the flow control valve 1 .
[0045] The lift cylinder 4 is an actuator for lifting and lowering the fork of the forklift according to the present invention. That is, the lift cylinder 4 lifts the fork of the forklift when hydraulic oil is supplied from the load pressure line 13 and lowers the fork of the forklift when hydraulic oil is discharged into the load pressure line 13 . At this time, the oil pressure of the load pressure line 13 varies depending on the weight of a load held by the fork of the forklift and becomes larger as the load is heavier.
[0046] The pressure compensating valve 5 controls the oil pressure of the compensating pressure line 14 so as to become a set pressure. That is, the pressure compensating valve 5 enlarges the opening area of a variable orifice between the load pressure line 13 and the compensating pressure line 14 when the oil pressure of the compensating pressure line 14 is smaller than the set pressure, and narrows the opening area of the variable orifice when the oil pressure of the compensating pressure line 14 is larger than the set pressure.
[0047] The direction switching valve 2 includes a relief valve 21 , an inlet side line 22 and an outlet side line 23 . The relief valve 21 prevents the oil pressure of the inlet side line 22 from exceeding a set pressure by providing the set pressure. The set pressure of the relief valve 21 is larger than that of the pressure compensating valve 5 . That is, the relief valve 21 connects the line 22 to the outlet side line 23 when the oil pressure of the inlet side line 22 is larger than that of the set pressure, and does not connect the line 22 to the outlet side line 23 when the oil pressure of the inlet side line 22 is smaller than that of the set pressure.
[0048] The direction switching valve 2 can occupy one of a neutral position, a meter-in position and a meter-out position. That is, operated by the user, the direction switching valve 2 is switched from the neutral position to the meter-in position, from the neutral position to the meter-out position, from the meter-in position to the neutral position and from the meter-out position to the neutral position.
[0049] At the meter-in position, the direction switching valve 2 connects the pump pressure line 11 to the pump pressure line 12 , closes the compensating pressure line 14 and closes the drain line 15 . At the meter-out position, the direction switching valve 2 closes the pump pressure line 11 , closes the pump pressure line 12 and connects the compensating pressure line 14 to the drain line 15 .
[0050] At the neutral position, the direction switching valve 2 closes the pump pressure line 11 , closes the pump pressure line 12 , connects the compensating pressure line 14 to the inlet side line 22 and connects the line 23 to the drain line 15 . That is, at the neutral position, the direction switching valve 2 performs control such that the oil pressure of the compensating pressure line 14 does not exceed the set pressure set for the relief valve 21 .
[0051] At the meter-out position, the direction switching valve 2 may connect the compensating pressure line 14 to the inlet line 22 and the line 23 to the drain line 15 . That is, at the meter-out position, the direction switching valve 2 may perform control such that the oil pressure of the compensating pressure line 14 does not exceed the set pressure set for the relief valve 21 .
[0052] The tank 6 stores hydraulic oil flowing through the drain line 15 therein. The hydraulic oil stored in the tank 6 is supplied to the pump pressure line 11 by a pump not shown.
[0053] FIG. 6 is a schematic perspective view showing the forklift with the flow control valve of the present invention. The forklift 7 includes the flow control valve 1 , the fork 8 and the lift cylinder 4 . The flow control valve 1 is included in a hydraulic circuit (not shown) mounted on the forklift 7 . The lift cylinder 4 is connected between the flow control valve 1 and the fork 8 . The fork 8 lifts and lowers a load. The lift cylinder 4 drives the folk 8 along with the flow control valve 1 . The fork 8 , for example, is composed of an outer mast 8 c , an inner mast 8 b and a fork body 8 . The inner mast 8 b is lifted up and down to the vertical direction guided by the outer mast 8 c . The fork body 8 a is lifted up and down supported by the inner mast 8 b in an integrated manner to the inner mast 8 b . The inner mast 8 b is driven to lift up and down by the lift cylinder 4 .
[0054] FIG. 3 is a cross sectional view showing the flow control valve main unit including the flow control valve 1 . The flow control valve main unit 30 includes a spool chamber 31 and a spool 32 which constitute the direction switching valve 2 . That is, the spool chamber 31 has a cylindrical sliding surface therein. The spool 32 is provided so as to internally touch the sliding surface of the spool chamber 31 and be slidably inserted thereinto in the direction parallel to a direction A. In the flow control valve main unit 30 , a pump pressure chamber 33 , a load pressure chamber 34 , a compensating pressure chamber 35 and a drain chamber 36 are provided in the spool chamber 31 . The pump pressure chamber 33 is connected to the pump pressure line 11 . The drain chamber 36 is connected to the drain line 15 .
[0055] By sliding in the direction parallel to the direction A, the spool 32 is set at any of the neutral position, the meter-in position and the meter-out position. That is, the spool 32 is set at the meter-in position by moving from the neutral position in the direction A, and is set at the meter-out position by moving from the neutral position in the direction opposite to the direction A. The spool 32 is mechanically connected to a lever operated by the operator through a link mechanism and moves in the direction parallel to the direction A in proportion to an operation quantity of the lever.
[0056] The spool 32 may be replaced with the other spool moved by the other moving mechanism. An electric hydraulic pilot mechanism is exemplified as the moving mechanism of the spool. The electric hydraulic pilot mechanism further includes a potentiometer and a solenoid valve. The potentiometer detects an operation quantity of the lever operated by the operator and outputs a current corresponding to the operation quantity to the solenoid valve directly or through a control device not shown. The solenoid valve applies a pressure to the hydraulic oil such that the hydraulic oil has a pilot pressure corresponding to the current. The spool 32 of the direction switching valve 2 is pressed by the hydraulic oil with the pilot pressure to be directly operated.
[0057] The spool chamber 31 and the spool 32 include a variable orifice 38 and a variable orifice 37 . The variable orifice 37 closes connection between the pump pressure chamber 33 and the load pressure chamber 34 when the spool 32 is set at the neutral position or the meter-out position, and connects the pump pressure chamber 33 to the load pressure chamber 34 when the spool 32 is set at the meter-in position. When the spool 32 is set at the meter-in position, the orifice area of the variable orifice 37 becomes larger as the spool 32 moves toward the direction A.
[0058] The variable orifice 38 closes connection between the compensating pressure chamber 35 and the drain chamber 36 when the spool 32 is set at the neutral position or the meter-in position, and connects the compensating pressure chamber 35 to the drain chamber 36 when the spool 32 is set at the meter-out position. When the spool 32 is set at the meter-out position, the orifice area of the variable orifice 38 becomes larger as the spool 32 moves toward the direction opposite to the direction A.
[0059] The spool 32 includes a spool chamber 41 , a spool 42 and a spring 43 which constitutes the relief valve 21 . The spool chamber 41 has a cylindrical sliding surface. The spool 42 is provided so as to internally touch the sliding surface of the spool chamber 41 and be slidably inserted thereinto in the direction parallel to a direction A. The spring 43 presses the spool 42 in the direction opposite to the direction A. In the spool 32 , a pressure chamber 44 is provided between the spool 42 and the spool chamber 41 .
[0060] The hydraulic oil of the pressure chamber 44 presses the spool 42 by its oil pressure in the direction A. That is, the spool 42 moves in the direction A when the oil pressure of the pressure chamber 44 is larger than the set pressure set by the spring 43 .
[0061] The spool 32 further includes a hole 45 and a hole 46 . The hole 45 is connected to the pressure chamber 44 . The hole 45 is not connected to the compensating pressure chamber 35 when the spool 32 is set at the meter-in position and is connected to the compensating pressure 35 when the spool 32 is set at the neutral position or the meter-out position.
[0062] The hole 46 is connected to the drain chamber 36 . The hole 46 is connected to the pressure chamber 44 when the spool 42 moves in the direction A, that is, when the oil pressure of the pressure chamber 44 is larger than the set pressure and is not connected to the pressure chamber 44 when the spool 42 does not move, that is, when the oil pressure of the pressure chamber 44 is smaller than the set pressure.
[0063] The flow control valve main unit 30 further includes a spool chamber 52 , a spool 51 and a spring 53 which constitute the pressure compensating valve 5 . That is, the spool chamber 52 has a cylindrical sliding surface. The spool 51 is provided so as to internally touch the sliding surface of the spool chamber 52 and be slidably inserted thereinto in the direction parallel to a direction A. The spring 53 presses the spool 52 in the direction opposite to the direction A.
[0064] In the flow control valve main unit 30 , the spool chamber 52 includes a load pressure chamber 54 , a compensating pressure chamber 55 and a pressure chamber 56 . The load pressure chamber 54 is connected to a load pressure line 13 . The compensating pressure chamber 55 is connected to the compensating pressure chamber 35 . A hole 57 is formed on the spool 51 . The hole 57 connects the compensating pressure chamber 55 to the pressure chamber 56 . The hydraulic oil of the pressure chamber 56 presses the spool 52 by its oil pressure toward the direction A.
[0065] The spool chamber 52 and the spool 51 include a variable orifice 58 . The variable orifice 58 narrows or closes the opening area between the load pressure chamber 54 and the compensating pressure chamber 55 when the spool 52 moves toward the direction A and enlarges the opening area when the spool 52 moves toward the direction opposite to the direction A.
[0066] Operations of the flow control valve 1 include the meter-in operation, the neutral operation and the meter-out operation. The meter-in operation is the operation performed when the direction switching valve 2 is switched from the neutral position to the meter-in position by the user. The neutral operation is the operation performed when the direction switching valve 2 is switched from the meter-in position or the meter-out position to the neutral position by the user. The meter-out operation is the operation performed when the direction switching valve 2 is switched from the neutral position to the meter-out position by the user.
[0067] In the meter-in operation, hydraulic oil is supplied from the pump pressure line 11 to the lift cylinder 4 through the direction switching valve 2 , the pump switching line 12 , the check valve 3 and the load pressure line 13 . The lift cylinder 4 lifts the fork when the hydraulic oil is supplied.
[0068] In the neutral operation, since no hydraulic oil is supplied or discharged to the lift cylinder 4 , lifting and lowering of the fork is stopped. The load pressure varies according to the weight of the load held by the fork of the forklift and becomes larger as the load is heavier. The hydraulic oil of the load pressure line 13 is supplied to the compensating pressure line 14 through the pressure compensating valve 5 . The pressure compensating valve 5 prevents the oil pressure of the compensating pressure line 14 from becoming the set pressure or more by closing connection between the load pressure line 13 and the compensating pressure line 14 when the oil pressure of the compensating pressure line 14 is raised to the set pressure of the pressure compensating valve 5 .
[0069] When the load pressure is larger than the set pressure, the pressure compensating valve 5 gradually leaks the hydraulic oil from the load pressure line 13 to the compensating pressure line 14 through a gap between the spool chamber 52 and the spool 51 with time even when connection between the load pressure line 13 and the compensating pressure line 14 is closed, and raises the oil pressure of the compensating pressure line 14 . When the oil pressure of the compensating pressure line 14 is raised to the set pressure of the relief valve 22 , the relief valve 22 connects the compensating pressure line 14 to the drain line 15 to flow the hydraulic oil of the compensating pressure line 14 to the drain line 15 and lowers the oil pressure of the compensating pressure line 14 to the set pressure.
[0070] In the meter-out operation, the hydraulic oil is discharged from the lift cylinder 4 to the drain line 15 through the load pressure line 13 , the pressure compensating valve 5 and the direction switching valve 2 . When the hydraulic oil is discharged, the lift cylinder 4 lowers the fork. At this time, the oil pressure of the compensating pressure line 14 is controlled to be the set pressure through the pressure compensating valve 5 irrespective of the weight of the load held by the fork. For this reason, in the meter-out operation, irrespective of the weight of the load held by the fork, the flow control valve 1 can associate the flow of the hydraulic oil discharged from the lift cylinder 4 to the drain line 15 with the operation quantity of the direction switching valve 2 on one-to-one basis. In other words, the forklift according to the present invention can associate the lowering speed of the fork with the operation quantity of the direction switching valve 2 on one-to-one basis, thereby improving operability of the fork.
[0071] In the case that the pressure of the compensating pressure line 14 is much higher than the set pressure, when the compensating pressure line 14 is connected to the drain line 15 , the hydraulic oil rapidly flows from the compensating pressure line 14 to the drain line 15 . The rapid flow generates shock or hunting in the operation of the lift cylinder 4 . The flow control valve 1 controls the oil pressure of the compensating pressure line 14 in the neutral operation such that the oil pressure of the compensating pressure line 14 may not exceed the set pressure of the relief valve 21 . Thus, the flow control valve 1 can prevent the hydraulic oil from rapidly flowing from the compensating pressure line 14 to the drain line 15 when the direction switching valve 2 is switched from the neutral position to the meter-out position. Therefore, the flow control valve 1 can prevent shock or hunting from occurring in the operation of the lift cylinder 4 . That is, the forklift according to the present invention can prevent shock or hunting in the fork from occurring when the fork is lowered.
[0072] FIG. 4 is a schematic view showing another embodiment of a flow control valve according to the present invention. The flow control valve 61 includes a direction switching valve 62 , a check valve 63 , a pressure compensating valve 65 , a direction switching valve 67 and a relief valve 68 . The flow control valve 61 further includes a plurality of lines for guiding hydraulic oil and transmitting oil pressure. The plurality of lines is composed of a pump pressure line 71 , a pump pressure line 72 , a load pressure line 73 , a compensating pressure line 74 , a drain line 75 , a compensating pressure line 77 and a drain line 78 .
[0073] The pump pressure line 71 connects the direction switching valve 62 to a pump not shown and guides the hydraulic oil supplied by the pump. The pump pressure line 72 connects the direction switching valve 62 to the check valve 63 . The load pressure line 73 connects between the check valve 63 , the lift cylinder 64 and the pressure compensating valve 65 . The compensating pressure line 74 connects between the pressure compensating valve 65 , the direction switching valve 62 and the direction switching valve 67 . The compensating pressure line 77 connects the direction switching valve 67 to the relief valve 68 . The drain line 75 connects the direction switching valve 62 to the tank 66 . The oil pressure of the drain line 75 is substantially zero (0). The drain line 78 connects the relief valve 68 to the tank 66 . The oil pressure of the drain line 78 is substantially zero (0).
[0074] The check valve 63 prevents the hydraulic oil from flowing from the load pressure line 73 to the pump pressure line 72 . That is, the check valve 63 connects the pump pressure line 72 to the load pressure line 73 when the oil pressure of the pump pressure line 72 is larger than that of the load pressure line 73 , and does not connect the pump pressure line 72 to the load pressure line 73 when the oil pressure of the load pressure line 73 is larger than that of the pump pressure line 72 .
[0075] The lift cylinder 64 is an actuator for lifting and lowering the fork of the forklift according to the present invention. That is, the lift cylinder 64 lifts the fork of the forklift when hydraulic oil is supplied from the load pressure line 73 and lowers the fork of the forklift when hydraulic oil is discharged into the load pressure line 73 . At this time, the oil pressure of the load pressure line 73 varies depending on the weight of a load held by the fork of the forklift and becomes larger as the load is heavier.
[0076] The pressure compensating valve 65 performs control such that the oil pressure of the compensating pressure line 74 is a set pressure. That is, the pressure control valve 65 enlarges the opening area of a variable orifice between the load pressure line 73 and the compensating pressure line 74 when the oil pressure of the compensating pressure line 74 is smaller than the set pressure, and narrows the opening area of the variable orifice when the oil pressure of the compensating pressure line 74 is larger than the set pressure.
[0077] The spool of the direction switching valve 62 can occupy one of the neutral position, the meter-in position and the meter-out position. That is, the direction switching valve 62 includes a potentiometer and a solenoid valve not shown. The potentiometer detects an operation quantity of the lever operated by the operator and outputs a current corresponding to the operation quantity to the solenoid valve directly or through a control device not shown. The solenoid valve applies a pressure such that the hydraulic oil has a pilot pressure corresponding to the current. The hydraulic oil is composed of two hydraulic oils. One is a hydraulic oil for pressing the spool of the direction switching valve 62 from right to left. The other is a hydraulic oil for pressing the spool of the direction switching valve 62 from left to right. The spool of the direction switching valve 62 is moved by being pressed by the hydraulic oil with the pilot pressure to be switched from the neutral position to the meter-in position and from the neutral position to the meter-out position.
[0078] At the meter-in position, the direction switching valve 62 connects the pump pressure line 71 to the pump pressure line 72 , closes the compensating pressure line 74 and closes the drain line 75 . At the meter-out position, the direction switching valve 62 closes the pump pressure line 71 , closes the pump pressure line 72 and connects the compensating pressure line 74 to the drain line 75 . At the neutral position, the direction switching valve 62 closes the pump pressure line 71 , closes the pump pressure line 72 , closes the compensating pressure line 74 and closes the drain line 75 .
[0079] The flow control valve 61 further includes a pilot pressure line 79 . The pilot pressure line 79 presses the spool of the direction switching valve 67 from left to right to transmit the pilot pressure of the hydraulic oil for moving the spool from the neutral position to the meter-in position to the direction switching valve 67 . The pilot pressure is raised when the spool of the direction switching valve 67 is moved from the neutral position to the meter-in position, and is not raised when the spool of the direction switching valve 67 is moved to the neutral position or the meter-out position.
[0080] When the pilot pressure is raised, the spool of the direction switching valve 67 is pressed by the pilot pressure to close connection between the compensating pressure line 74 and the compensating pressure line 77 . When the pilot pressure is not raised, the spool of the direction switching valve 67 is pressed by the pilot pressure to connect the compensating pressure line 74 to the compensating pressure line 77 . That is, the direction switching valve 67 closes connection between the compensating pressure line 74 and the compensating pressure line 77 when the spool of the direction switching valve 67 is set at the meter-in position, and connects the compensating pressure line 74 to the compensating pressure line 77 when the spool of the direction switching valve 67 is set at the neutral position or the meter-out position.
[0081] The relief valve 68 performs control such that the oil pressure of the compensating pressure line 77 does not exceed the set pressure. The set pressure of the relief valve 68 is larger than the set pressure of the pressure compensating valve 65 . That is, the relief valve 68 connects the compensating pressure line 77 to the drain line 78 when the oil pressure of the compensating pressure line 77 is larger than the set pressure, and does not connect the compensating pressure line 77 to the drain line 78 when the oil pressure of the compensating pressure line 77 is smaller than the set pressure.
[0082] The tank 66 stores hydraulic oil flowing through the drain line 75 and the drain line 78 therein. The hydraulic oil stored in the tank 66 is supplied to the pump pressure line 71 by a pump not shown.
[0083] As shown in FIG. 6 , the flow control valve 61 is mounted on the forklift 7 of the present invention. The forklift 7 includes the flow control valve 61 , the fork 8 and the lift cylinder 64 . The flow control valve 61 is included in a hydraulic circuit (not shown) mounted on the forklift 7 . The lift cylinder 64 is connected between the flow control valve 61 and the fork 8 . The fork 8 lifts and lowers a load. The lift cylinder 64 drives the folk 8 along with the flow control valve 61 .
[0084] Operations of the flow control valve 61 include the meter-in operation, the neutral operation and the meter-out operation. The meter-in operation is an operation performed when the direction switching valve 62 is switched from the neutral position to the meter-in position by means of the user's operation. The neutral operation is an operation performed when the direction switching valve 62 is switched from the meter-in position or the meter-out position to the neutral position by means of the user's operation. The meter-out operation is an operation performed when the direction switching valve 62 is switched from the neutral position to the meter-out position by means of the user's operation.
[0085] In the meter-in operation, the hydraulic oil supplied by the pump is supplied from the pump pressure line 71 to the lift cylinder 64 through the direction switching valve 62 , the pump pressure line 72 , the check valve 63 and the load pressure line 73 . When the hydraulic oil is supplied, the lift cylinder 64 lifts the fork.
[0086] In the neutral operation, since no hydraulic oil is supplied or discharged between the lift cylinder 64 and the load pressure line 73 , lifting or lowering of the fork is stopped. The load pressure varies depending on a load held by the fork of the forklift and becomes larger as the load is heavier. The hydraulic oil of the load pressure line 73 is supplied to the compensating pressure line 74 through the pressure compensating valve 65 . The pressure compensating valve 65 closes connection between the load pressure line 73 and the compensating pressure line 74 , when the oil pressure of the compensating pressure line 74 is raised to the set pressure of the pressure compensating valve 65 , thereby preventing the oil pressure of the compensating pressure line 74 from exceeding the set pressure. The direction switching valve 67 connects the compensating pressure line 74 to the compensating pressure line 77 .
[0087] When the load pressure is larger than the set pressure, the pressure compensating valve 65 gradually leaks the hydraulic oil from the load pressure line 73 to the compensating pressure line 74 through a gap between the spool chamber and the spool with time even when connection between the load pressure line 73 and the compensating pressure line 74 is closed, and raises the oil pressure of the compensating pressure line 74 . When the oil pressure of the compensating pressure line 77 is raised to the set pressure of the relief valve 68 , the relief valve 68 connects the compensating pressure line 77 to the drain line 78 to flow the hydraulic oil of the compensating pressure line 77 to the drain line 78 and lowers the oil pressure of the compensating pressure line 77 to the set pressure.
[0088] In the meter-out operation, the hydraulic oil is discharged from the lift cylinder 64 to the drain line 15 through the load pressure line 73 , the pressure compensating valve 65 , the compensating pressure line 74 and the direction switching valve 62 . When the hydraulic oil is discharged, the lift cylinder 64 lowers the fork. At this time, the oil pressure of the compensating pressure line 74 is controlled by the pressure compensating valve 65 to be the set pressure irrespective of the weight of the load held by the fork. For this reason, in the meter-out operation, irrespective of the weight of the load held by the fork, the flow control valve 61 can associate the flow of the hydraulic oil discharged from the lift cylinder 64 to the drain line 75 with the operation quantity of the direction switching valve 62 on one-to-one basis. In other words, the forklift according to the present invention can associate the lowering speed of the fork with the operation quantity of the direction switching valve 62 on one-to-one basis, thereby improving operability of the fork.
[0089] Like the flow control valve 1 in the above-mentioned embodiment, the flow control valve 61 controls the oil pressure of the compensating pressure line 74 in the neutral position is controlled so as to be smaller than the set pressure of the relief valve 68 . The flow control valve 61 has more complicated configuration than the flow control valve 1 in the above-mentioned embodiment since the direction switching valve 67 is provided. However, similarly to the flow control valve 1 in the above-mentioned embodiment, the flow control valve 61 can prevent shock or hunting from occurring in the operation of the lift cylinder 64 . That is, the relief valve performs control such that the oil pressure of the compensating pressure line 74 in the neutral position does not exceed the set pressure. The relief valve can be installed inside or outside of the direction switching valve operated by the operator and thus no attention is paid to the installation position.
[0090] FIG. 5 is a schematic view showing still another embodiment of a flow control valve according to the present invention. The flow control valve 81 includes a direction switching valve 82 , a check valve 83 and a pressure compensating valve 85 . The flow control valve 81 further includes a plurality of lines for guiding hydraulic oil and transmitting oil pressure. The plurality of lines is composed of a pump pressure line 91 , a pump pressure line 92 , a load pressure line 93 , a compensating pressure line 94 and a drain line 95 .
[0091] The pump pressure line 91 connects the direction switching valve 82 to a pump not shown and guides the hydraulic oil supplied by the pump. The pump pressure line 92 connects the direction switching valve 82 to the check valve 83 . The load pressure line 93 connects between the check valve 83 , the lift cylinder 84 and the pressure compensating valve 85 . The compensating pressure line 94 connects the pressure compensating valve 85 to the direction switching valve 82 . The drain line 95 connects the direction switching valve 82 to the tank 86 and the oil pressure of the drain line 95 is substantially zero (0).
[0092] The check valve 83 prevents the hydraulic oil from flowing from the load pressure line 93 to the pump pressure line 92 . That is, the check valve 83 connects the pump pressure line 92 to the load pressure line 93 when the oil pressure of the pump pressure line 92 is larger than that of the load pressure line 93 , and does not connect the pump pressure line 92 to the load pressure line 93 when the oil pressure of the load pressure line 93 is larger than that of the pump pressure line 92 .
[0093] The lift cylinder 84 is an actuator for lifting and lowering the fork of the forklift according to the present invention. That is, the lift cylinder 84 lifts the fork of the forklift when hydraulic oil is supplied from the load pressure line 93 and lowers the fork of the forklift when hydraulic oil is discharged into the load pressure line 93 . At this time, the oil pressure of the load pressure line 93 varies depending on the weight of a load held by the fork of the forklift and becomes larger as the load is heavier.
[0094] The pressure compensating valve 85 performs control such that the oil pressure of the compensating pressure line 94 is a set pressure. That is, the pressure control valve 85 enlarges the opening area of a variable orifice between the load pressure line 93 and the compensating pressure line 94 when the oil pressure of the compensating pressure line 94 is smaller than the set pressure, and narrows the opening area of the variable orifice when the oil pressure of the compensating pressure line 94 is larger than the set pressure.
[0095] The direction switching valve 82 can occupy one of the neutral position, the meter-in position and the meter-out position. That is, the direction switching valve 82 is switched from the neutral position to the meter-in position, from the neutral position to the meter-out position, from the meter-in position to the neutral position and from the meter-out position to the neutral position by the user's operation.
[0096] At the meter-in position, the direction switching valve 82 connects the pump pressure line 91 to the pump pressure line 92 , closes the compensating pressure line 94 and closes the drain line 95 . At the meter-out position, the direction switching valve 82 closes the pump pressure line 91 , closes the pump pressure line 92 and connects the compensating pressure line 94 to the drain line 95 . At the neutral position, the direction switching valve 82 closes the pump pressure line 91 , closes the pump pressure line 92 , closes the compensating pressure line 94 and closes the drain line 95 .
[0097] The tank 86 stores hydraulic oil flowing through the drain line 95 therein. The hydraulic oil stored in the tank 86 is supplied to the pump pressure line 91 by the pump not shown.
[0098] As shown in FIG. 6 , the flow control valve 81 is mounted on the forklift 7 of the present invention. The forklift 7 includes the flow control valve 81 , the fork 8 and the lift cylinder 84 . The flow control valve 81 is included in a hydraulic circuit (not shown) mounted on the forklift 7 . The lift cylinder 84 is connected between the flow control valve 81 and the fork 8 . The fork 8 lifts and lowers a load. The lift cylinder 84 drives the folk 8 along with the flow control valve 81 .
[0099] Operations of the flow control valve 81 include the meter-in operation, the neutral operation and the meter-out operation. The meter-in operation is an operation performed when the direction switching valve 82 is switched from the neutral position to the meter-in position by means of the user's operation. The neutral operation is an operation performed when the direction switching valve 82 is switched from the meter-in position or the meter-out position to the neutral position by means of the user's operation. The meter-out operation is an operation performed when the direction switching valve 82 is switched from the neutral position to the meter-out position by means of the user's operation.
[0100] In the meter-in operation, the hydraulic oil is supplied from the pump pressure line 91 to the lift cylinder 84 through the direction switching valve 82 , the pump pressure line 92 , the check valve 83 and the load pressure line 93 . When the hydraulic oil is supplied, the lift cylinder 84 lifts the fork.
[0101] In the neutral operation, since no hydraulic oil is supplied or discharged between the lift cylinder 84 and the load pressure line 93 , lifting or lowering of the fork is stopped. The load pressure of the hydraulic oil of the load pressure line 93 varies depending on a load held by the fork of the forklift and becomes larger as the load is heavier. The hydraulic oil of the load pressure line 93 is supplied to the compensating pressure line 94 through the pressure compensating valve 85 . The pressure compensating valve 85 closes connection between the load pressure line 93 and the compensating pressure line 94 , when the oil pressure of the compensating pressure line 94 is raised to the set pressure of the pressure compensating valve 85 , thereby preventing the oil pressure of the compensating pressure line 94 from becoming the set pressure or more.
[0102] In the meter-out operation, the hydraulic oil is discharged from the lift cylinder 84 to the drain line 95 through the load pressure line 93 , the pressure compensating valve 85 , the compensating pressure line 94 and the direction switching valve 82 . When the hydraulic oil is discharged, the lift cylinder 84 lowers the fork. At this time, the oil pressure of the compensating pressure line 94 is controlled by the pressure compensating valve 85 to be the set pressure irrespective of the weight of the load held by the fork. At this time, in the meter-out operation, irrespective of the weight of the load held by the fork, the flow control valve 81 can associate the flow of the hydraulic oil discharged from the lift cylinder 84 to the drain line 95 with the operation quantity of the direction switching valve 82 on one-to-one basis. In other words, the forklift according to the present invention can associate the lowering speed of the fork with the operation quantity of the direction switching valve 82 on one-to-one basis, thereby improving operability of the fork.
[0103] In the case of high pressure of the compensating pressure line 94 , when the compensating pressure line 94 is connected to the drain line 95 , the hydraulic oil rapidly flows from the compensating pressure line 94 to the drain line 95 . The rapid flow generates shock or hunting in the operation of the lift cylinder 84 . Since the flow control valve does not control the oil pressure of the compensating pressure line 94 in the neutral operation, when the direction switching valve 82 is switched from the neutral position to the meter-out position, the hydraulic oil cannot be prevented from rapidly flowing from the compensating pressure line 94 to the drain line 95 . Although the forklift to which the flow control valve 81 is applied cannot prevent shock or hunting from generating in the fork when the fork is lowered, it is better than that the lowering speed of the fork cannot be associated with the operation quantity of the direction switching valve 82 on one-to-one basis.
[0104] A flow control valve according to the present invention can improve operability of a hydraulic actuator.
[0105] It is apparent that the present invention is not limited to the above embodiment, that may be modified and changed without departing form the scope and spirit of the invention.
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A flow control valve includes a pressure compensating valve and a first switching valve. The pressure compensating valve is configured to enlarge an opening area of a variable orifice between a load pressure line and a compensating pressure line when a pressure of working fluid of the compensating pressure line is smaller than a first set pressure, and narrow the opening area of the variable orifice when the pressure of the working fluid of the compensating pressure line is larger than the first set pressure. The first switching valve is configured to switch between a meter-out operation and a neutral operation by an external operation, wherein the working fluid of the compensating pressure line is drained in the meter-out operation, the working fluid of the compensating pressure line is not drained in the neutral operation. The load pressure line guides the working fluid to be supplied to an actuator.
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FIELD OF THE INVENTION
This invention relates to nucleic acid delivery vehicle constructs that have an enhanced capability of expression in target cells, namely to hepatocytes and other liver cells.
BACKGROUND OF THE INVENTION
The ability to deliver nucleic acids carried by delivery vehicles, e.g., recombinant viruses (adenovirus, adeno-associated virus, herpesvirus, retrovirus) which are used with nucleic acid molecules, such as a plasmid, comprising a transgene, to transfect a target cell; molecular conjugate vectors; and modified viral vectors are important for the potential treatment of genetic diseases through gene delivery.
Adenovirus is a non-enveloped, nuclear DNA virus with a genome of about 36 kb. See generally, Horwitz, M. S., “Adenoviridae and Their Replication,” in Virology, 2nd edition, Fields et al., eds., Raven Press, New York, 1990. Recombinant (adenovirus dodecahedron and recombinant adenovirus conglomerates) to specific cell types is useful for various applications in oncology, developmental biology and gene therapy. Adenoviruses have advantages for use as expression systems for nucleic acid molecules coding for, inter alia, proteins, ribozymes, RNAs, antisense RNA that are foreign to the adenovirus carrier (i.e. a transgene), including tropism for both dividing and non-dividing cells, minimal pathogenic potential, ability to replicate to high titer for preparation of vector stocks, and the potential to carry large inserts. See Berkner, K. L., 1992, Curr. Top. Micro Immunol, 158:39-66; Jolly D., 1994, Cancer Gene Therapy, 1:51-64.
Adenoviruses have a natural tropism for respiratory tract cells, which has made them attractive vectors for use in delivery of genes to respiratory tract cells. For example, adenovirus vectors have been and are being designed for use in the treatment of certain diseases, such as cystic fibrosis (CF): the most common autosomal recessive disease in Caucasians. In CF, mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene disturb cAMP-regulated chloride channel function, resulting in pulmonary dysfunction. The gene mutations have been found to encode altered CFTR proteins which cannot be translocated to the cell membrane for proper functioning. The CFTR gene has been introduced into adenovirus vectors to treat CF in several animal models and human patients. Particularly, studies have shown that adenovirus vectors are fully capable of delivering CFTR to airway epithelia of CF patients, as well as airway epithelia of cotton rats and primates. See e.g., Zabner et al., 1994, Nature Genetics, 6:75-83; Rich et al., 1993, Human Gene Therapy, 4:461-476; Zabner et al., 1993, Cell, 75:207-216; Zabner et al., 1994, Nature Genetics 6:75-83; Crystal et al., 1004, Nature Genetics, 8:42-51; Rich et al., 1993, Human Gene Therapy, 4:461-476.
However, it would be useful to alter the genome of adenovirus, to allow it to be used to deliver a nucleic acid molecule that would be enhanced for expression in the liver, particularly in hepatocytes.
It would be useful to mediate expression of the transgene carried by the adenoviral vector through the use of one or more specialized regulatory elements. In this way the expression of transgene within desired cells can be enhanced and the adenovirus effects can be targeted to certain cells or tissues within an organism.
Like adenoviruses, retroviruses have also been used for delivery of transgenes to target cells. As set forth above, a transgene is a nucleic acid molecule that codes for, inter alia, a protein, RNA, ribozyme, antisense RNA not produced by the virus. Retrovirus virions range in diameter from 80 to 130 nm and are made up of a protein capsid that is lipid encapsulated. The viral genome is encased within the capsid along with the proteins integrase and reverse transcriptase. The retrovirus genome consists of two RNA strands. After the virus enters the cells, the reverse transcriptase synthesizes viral DNA using the viral RNA as its template. The cellular machinery then synthesizes the complementary DNA which is then circularized and inserted into the host genome. Following insertion, the viral RNA genome is transcribed and viral replication is completed.
Examples of retroviruses include Moloney murine leukemia virus (Mo-MuLV), HTLV and HIV retroviruses. Mo-MuLV vectors are most commonly used and are produced simply by replacing viral genes required for replication with the desired transgenes to be transferred. The genome in retroviral vectors contains a long terminal repeat sequence (LTR) at each end with the desired transgene or transgenes in between. The most commonly used system for generating retroviral vectors consists of two parts, the retroviral vector and the packaging cell line.
Retroviruses are typically classified by their host range. For example, ecotropic viruses are viruses which bind receptors unique to mice and are only able to replicate within the murine species. Xenotropic viruses bind receptors found on all cells in most species except those of mice. Polytropic and amphotropic viruses bind different receptors found in both murine and nonmurine species. The host range is determined primarily by the binding interaction between viral envelope glycoproteins and specific proteins on the host cell surface that act as viral receptors. For example, in murine cells, an amino acid transporter serves as the receptor for the envelope glycoprotein gp70 of ecotropic Moloney murine leukemia virus (Mo-MuLV). The receptor for the amphotropic MoMuLV has recently been cloned and shows homology to a phosphate transporter. There are six known receptors for retroviruses: CD4 (for HIV); CAT (for MLV-E (ecotropic Murine leukemic virus E); RAM1/GLVR2 (for murine leukemic virus-A (MLV-A)); GLVRI (for Gibbon Ape leukemia virus (GALV) and Feline leukemia virus B (FeLV-B). RAM1 and GLVR1 receptors are broadly expressed in human tissues.
Retrovirus packaging cell lines provide all the viral proteins required for capsid production and the virion maturation of the vector, i.e., the gag, pol and env genes. For the MMLV vectors, it is the packaging cell line that determines whether the vector is ecotropic, xenotropic or amphotropic. The choice of the packaging cell line determines the cells that will be targeted. Thus, the usefulness of retroviruses for gene transfer is limited by the fact that they are receptor specific.
However, retroviruses are useful for gene delivery systems because they have a high infection efficiency and the retroviral nucleic acid (after reverse transcription) integrates into the host genome resulting in sustained expression of the transgenes carried by the vector. However, typical retroviral vectors are limited in that they require dividing cells for infectivity. Furthermore, in vivo delivery of these vectors is poor and is effective only when infecting helper cell lines. Thus, it would be useful to have a system for increasing the efficiency of retroviral infection.
Certain situations exist where it would be useful to modify the expression of transgenes carried by viruses. For example, tissue-specific expression of the transgene in targeted cells might increase the efficiency of infection, and consequently, a lower volume of virus may be effective in the body. It would be useful to have a method of up-regulating the expression of the transgene in a tissue-specific manner.
One method for targeting specific cell populations to express a protein of interest is to use heterologous regulatory elements that are specifically expressed in the desired target tissue or cell populations. This may be achieved through the use of combinations of tissue-specific enhancers, promoters and/or other regulatory elements. The regulatory elements may be constitutive or inducible, such that they are regulated by the absence or presence of other DNA sequences, proteins or other elements or environmental factors. Where the transgene of interest is a cytotoxic gene, leaky expression would be highly undesirable.
SUMMARY OF THE INVENTION
Accordingly, the present invention provides improved regulatory elements that are useful for targeting transgene expression to the liver. In preferred embodiments, the regulatory elements comprise combinations of promoter and enhancer elements that are able to direct transgene expression preferentially in liver. In particular embodiments, the regulatory elements are used in recombinant vectors, such as such as nonviral plasmid based vectors or such as viral vectors, including adenovirus, adeno-associated virus, retrovirus and lentivirus, including the human immunodeficiency [HIV] virus. In other embodiments, the invention comprises recombinant vectors useful for transgene expression, particularly for high and sustained expression in the liver, such as viral vectors. The vectors comprise combinations of a constitutive or high-expressing promoter and one or more liver-specific enhancer elements.
Thus, the present invention comprises recombinant transgenes comprising strong constitutive promoters and one or more liver-specific enhancer elements. The transgenes may be used in recombinant vectors, such as recombinant viral vectors, for targeting expression of the associated coding DNA sequences preferentially in liver. In preferred embodiments, the strong constitutive promoter is selected from the group comprising a CMV promoter, a truncated CMV promoter, human serum albumin promoter and α-1-antitrypsin promoter. In other preferred embodiments, the promoter is a truncated CMV promoter from which binding sites for known transcriptional repressors have been deleted.
In other embodiments, the liver-specific enhancer elements are selected from the group consisting of human serum albumin [HSA] enhancers, human prothrombin [HPrT] enhancers, α-1microglobulin enhancers and intronic aldolase enhancers. One or more of these liver-specific enhancer elements may be used in combination with the promoter. In one preferred embodiment of the invention, one or more HSA enhancers are used in combination with a promoter selected from the group consisting of a CMV promoter or an HSA promoter. In another preferred embodiment, one or more enhancer elements selected from the group consisting of human prothrombin (HPrT) enhancers and α-1microglobulin (A1MB) enhancers are used in combination with the CMV promoter. In yet another preferred embodiment, the enhancer elements are selected from the group consisting of HPrT enhancers and A1MB enhancers, and are used in combination with the α-1-antitrypsin promoter.
The preferred embodiments of the present invention are recombinant viral vectors, particularly adenoviral vectors. In the preferred embodiments, the coding DNA sequence may encode a therapeutic protein that is most effective when delivered to the liver. The adenoviral vectors may comprise, in addition to the promoters and enhancers of the present invention, one or more adenoviral genes in order to support the efficient expression of the coding DNA sequence.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a depiction of the transcription factor binding sites present in the CMV, HSA and α-1 antitrypsin promoter regions.
FIG. 2 is a depiction of the transcription factor binding sites present in the HSA enhancers (HSA-1.7, nucleotides −1806 to −1737; HSA-6, nucleotides −6081 to −6000), a human prothrombin enhancer (−940 to −860), an α-1microglobulin enhancer (−2806 to −2659) and an intronic aldolase enhancer (+1916 to +2329).
FIG. 3 is a schematic representation of an initial series of enhancer/promoter combinations. Group A indicates the combinations of the HSA enhancers that were linked to either the mCMV or HSA promoter. Groups B and C represent the combinations of either the human prothrombin (HPrT) or α-1microglobulin (A1MB) enhancer linked to the mCMV promoter. Groups D and E represent the combinations of of either HPrT or A1MB linked to the α-1-antitrypsin promoter.
FIG. 4 depicts expression from mCMV promoter compared to that of hCMV promoter, and the effects of adding multiple HSA enhancers (HSA-1.7 and HSA-6).
FIG. 5 depicts expression from constructs containing the HPrT enhancer. Linkage of this enhancer to the mCMV promoter (Panel B) elevated expression to near levels achieved with the CMV promoter but did not exceed it. Expression from the α-1-antitrypsin promoter was rather poor, however when two copies of the HPrT enhancer are added expression from this combination exceeds that from the CMV promoter.
FIG. 6 depicts expression results from constructs containing the A1MB enhancer. Progressively increased expression is seen with increasing copy number of this enhancer (up to eight copies) linked to the mCMV promoter (Panel C). All copy combinations of this enhancer linked to the α-1-antitrypsin promoter yielded expression levels comparable to that obtained with the CMV promoter (Panel E).
FIG. 7 depicts expression results obtained with representative candidates from each vector series that yielded equivalent or higher levels of α-galactosidase expression compared to the CMV promoter.
FIG. 8 demonstrates the expression of FVIII in SCID Beige Mice. The Factor VIII expression cassettes used contained either the CMV promoter or a hybrid promoter composed of two copies of the hprt enhancer linked to a human α-1-antitrypsin promoter fragment (Hprt(2)AAT). Ten μg of plasmid DNA containing either cassette was injected via the tail vein of SCID beige mice using Mirus plasmid delivery technology. Mice were bled at one, seven and fourteen days post-injection and FVIII levels in the plasma were determined by an ELISA that is specific for human FVIII. Each bar represents the average FVIII expression in the plasma of four mice.
Expression levels detected on day one were comparable in mice that received either plasmid indicating that the hybrid promoter could yield expression levels that approximate that from the CMV promoter. However, expression from the CMV promoter was transient and plummeted to undetectable by day seven whereas expression from the hybrid promoter persisted to day 14 (the last time point of this experiment). This suggests that this hybrid promoter is a better choice for achieving long-term transgene expression in the liver.
FIG. 9 demonstrates the AAV mediated expression of recombinant human erythropoietin [EPO] in mice. From promoter studies in cultured Hep3B cells, several enhancer/promoter combinations were identified as promising candidates for achieving long-term expression in the liver. From this panel of combinations, several were cloned into AAV vectors to test their ability to drive expression of recombinant human EPO. 1×10e11 particles of each AAV vector was administered to NCR nude mice by portal vein injection. On days 14, 28 and 42 post-injection, the mice were bled retro-orbitally and EPO levels were determined by an ELISA specific for human EPO. All promoters shown in the above figure gave rise to persistent expression out to day 42. However from this analysis, three enhancer/promoter combinations emerge as being the most promising for yielding high persistent levels of expression. Two copies of the hprt enhancer linked to either the α-1AT or HSA promoters and two copies of the α-1-microglobulin enhancer linked to the α-1-AT promoter yielded expression ranging from 1500 to 3000 mU EPO/ml or from 300 μg to 600 μg protein/ml.
DETAILED DESCRIPTION OF THE INVENTION
The delivery of genes to the liver for therapeutic purposes has been explored extensively. This includes investigation aimed at correction of genetic diseases of the liver as well as systemic diseases that might be corrected by using the liver as a depot for therapeutic protein production. For this gene therapy approach to be feasible, expression of the therapeutic gene must be long-lived and approach appropriate levels. In several reports, the use of a variety of viral, non-viral, and liver specific promoters as well as various enhancer/promoter combinations has been explored in the context of adenoviral, AAV, retroviral and plasmid-based vectors for gene expression in cultured cells and in vivo. In many of these examples transgene expression was transient and/or not sufficient to achieve therapeutic benefit. In the context of adenoviral vectors, the CMV promoter and RSV promoter direct high levels of transgene expression however the longevity of expression is dependent upon retention of the adenoviral E4 region in the vector. The development of an enhancer/promoter combination that can direct sustained and appropriate levels of transgene expression in the context of a variety of vector systems would therefore be of benefit.
Promoters which are suitable for the present invention may be any strong constitutive promoter which is capable of promoting expression of an associated coding DNA sequence in the liver. Such strong constitutive promoters include the human and murine cytomegalovirus [CMV] promoter, truncated CMV promoters, human serum albumin promoter [HAS] and α-1-antitrypsin promoter. In a specific embodiment, the promoter used is a truncated CMV promoter from which binding sites for known transcriptional repressors have been deleted.
The liver-specific enhancer elements useful for the present invention may be any liver-specific enhancer that is capable of enhancing tissue-specific expression of an associated coding DNA sequence in the liver. Such liver-specific enhancers include one or more human serum albumin enhancers, human prothrombin enhancers, α-1 microglobulin enhancers and an intronic aldolase enhancers. In preferred embodiments, multiple enhancer elements may be combined in order to achieve higher expression.
Among the preferred embodiments of the present invention are vectors comprising one or more HSA enhancers in combination with either a CMV promoter or an HSA promoter; one or more enhancer elements selected from the group consisting of the human prothrombin (HPrT) enhancer and the α-1microglobulin (A1MB) enhancer in combination with a CMV promoter; and one or more enhancer elements selected from the group consisting of HPrT enhancers and A1MB enhancers, in combination with an α-1-antitrypsin promoter.
The strategy for achieving high and sustained levels of transgene expression involves combining promoter elements that have the potential to direct effective and sustained levels of expression with liver specific enhancer elements that can further increase expression. The promoter fragments preferred for use in the present invention include a truncated version of the CMV promoter (mCMV, nucleotides −245 to −14), human serum albumin promoter (−486 to +20) and α-1-antitrypsin promoter (−844 to −44). The truncated CMV promoter is missing binding sites for known transcriptional repressors and is thus a preferred version of this promoter. The human serum albumin and the α-1-antitrypsin promoter contain elements that direct basal yet liver specific expression. The transcription factor binding sites in these promoter regions are depicted in FIG. 1 . The enhancer elements used here include two HSA enhancers (HSA-1.7, nucleotides −1806 to −1737; HSA-6, nucleotides −6081 to −6000), a human prothrombin enhancer (−940 to −860), an α-1microglobulin enhancer (−2806 to −2659) and an intronic aldolase enhancer (+1916 to +2329). Each of these enhancers has been shown to greatly increase transgene expression when linked to a minimal promoter and transcription factor binding sites in these enhancer elements is depicted in FIG. 2 . FIG. 3 is a schematic representation of an initial series of enhancer/promoter combinations. Group A indicates the combinations of the HSA enhancers that were linked to either the mCMV or HSA promoter. Groups B and C represent the combinations of either the human prothrombin (HPrT) or α-1microglobulin (A1MB) enhancer linked to the mCMV promoter. Groups D and E represent the combinations of either HPrT or A1MB linked to the α-1-antitrypsin promoter.
Each of these enhancer/promoter combinations was linked to α-galactosidase and was tested for activity in Hep3B cells by measuring the levels of α-galactosidase in the supernatant medium following transient transfection. As shown in FIG. 4 , expression from the mCMV promoter is reduced compared to the CMV promoter. However, the combination of five copies of the HSA-1.7 enhancer with one copy of the HSA-6 enhancer linked to the mCMV promoter yielded expression that was higher than that obtained with the CMV promoter. The expression results from constructs containing the HPrT enhancer are shown in FIG. 5 . Linkage of this enhancer to the mCMV promoter (Panel B) elevated expression to near levels achieved with the CMV promoter but did not exceed it. Expression from the α-l-antitrypsin promoter was rather poor, however when two copies of the HPrT enhancer are added expression from this combination exceeds that from the CMV promoter. The expression results from constructs containing the A1MB enhancer are shown in FIG. 6 . Progressively increased expression is seen with increasing copy number of this enhancer (up to eight copies) linked to the mCMV promoter (Panel C). All copy combinations of this enhancer linked to the α-1-antitrypsin promoter yielded expression levels comparable to that obtained with the CMV promoter (Panel E). Representative candidates from each vector series that yielded equivalent or higher levels of α-galactosidase expression compared to the CMV promoter were retested in a single experiment. As shown in FIG. 7 , all enhancer/promoter combinations yielded comparable expression with expression from the HSA-1.7(5) HSA-6(1)mCMV and HPrT(2)A1AT promoters being the highest. These results demonstrate that high levels of expression are achievable by combining multiple copies of liver specific enhancers with various promoter elements.
EXAMPLES
1. Plasmid Constructions
The alpha one antitrypsin promoter (−1200 to +44) was PCR-amplified with Vent DNA polymerase (New England Bio Labs, Beverly, Mass. USA) from an in-house pBr 322 vector that contains a 19-kb genomic Sal I fragment which includes human PI derived from phage clone αNN (Dycaico et al. Science 242:1409-1412. 1988). The promoter was then cloned between the Hind III-EcoR I sites of pBluescript II SK+ (Stratagene, La Jolla, Calif. USA) to generate pBs A1AT. The sequence was analyzed using a PE Biosystems 377 automated sequencer. The hybrid alpha-galactosidase cassette from an in-house vector was cloned into the Spe I site of pBs A1AT to generate pBs A1AT HI AGAL. The alpha one antitrypsin hybrid intron alpha-galactosidase cassette was then subcloned into the pAdQuick (formerly pAdvantage) shuttle vector Sv2 ICEU I to generate Sv2 A1AT HI AGAL.
Human liver specific enhancer elements from albumin 60 bp and 81 bp; (1.7 kb and 6 kb from the transcription initiation site, respectively); prothrombin 81 bp (−940 to −860); and Alpha-1 microglobulin/Bikunin 154 bp (−2806 to −2653) were obtained via PCR from genomic DNA or through oligo synthesis. Multiple copies were cloned into Bluescript II SK+ (Stratagene, La Jolla Calif., USA). These enhancer elements were then subcloned into Sv2 A1AT HI AGAL via Cla 1-Stu 1, reducing the alpha one antitrypsin promoter to (−844 to +44) or subcloned into the in-house vector Sv2 CMV HI AGAL II via Cla 1-SnaB 1, truncating the wild-type cytomegalovirus promoter to (−245 to −14).
2. Hep3 B Transfections
Six well plates were seeded with Hep3 B cells at 2×10 5 cells per well. Diluted 2.5 μg enhancer construct +2.5 ug CMV B (Stratagene, La Jolla, Calif. USA) in 1.5 mls opti-mem reduced serum media (Gibco BRL, Gaithersburg, Md. USA). Diluted 20 μl lipofectamine 2000 (Gibco BRL, Gaithersburg, Md. USA) in 1.5 mls opti-mem reduced serum media. The two solutions were mixed and then incubated at room temperature for 30 min. While complexes formed, cells were rinsed twice with opti-mem reduced serum media. Incubated cells with the lipid solution (1.5 mls solution per well) for 3-4 hrs at 37° c. in 5% co 2 incubator. Cells were rinsed once with 1×PBS and the lipid solution was replaced with 2 mls Mem media containing 1 mM Sodium pyruvate and 10% Fetal Bovine Serum. (Gibco BRL, Gaithersburg, Md. USA).
3. Alpha-galactosidase Fluorescent Assay
One hundred microliters of supernatant from hepatoma transfections were transferred into 96-well plate (Corning flat bottom). Five-fold dilutions were prepared to 1:125. Alpha-galactoside A enzyme (Genzyme, Framingham, Mass. USA) was diluted two fold 1250 uU/ml to 19.5 uU/ml to generate a standard curve. Substrate solution (1.69 mg/ml 4-methylumbelliferyl-a-D-galactoside and 26 mg/ml N-acetyl-D-galactosamine) in a buffer containing 27 mM citric acid, 46 mM sodium phosphate dibasic pH4.4 was added to the samples. Samples were incubated at 37° C. for 3 hours. The reactions were terminated with the addition of fifty microliters of a one molar sodium hydroxide solution. Spectra Max Gemini (Molecular Devices Co. Sunnyvale, Calif. USA) were read with excitation filter 365 nm and emission filter 450 nm. Alpha-galactosidase activity was normalized to α-galactosidase activity in transfection cell lysates using Galacto-light Plus kit. (Tropix, Bedford, Mass., USA). All α-galactosidase assay reagents were obtained from Sigma, St. Louis, Mo., USA.
The disclosures of all references disclosed herein are hereby incorporated by reference. The invention has been described in detail with particular reference to preferred embodiments thereof. However, it is contemplated that modifications and improvements within the spirit and teachings of this invention may be made by those in the art upon considering the present disclosure. Such modifications and improvements constitute part of the present claimed invention.
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The invention is directed to novel combinations of liver specific enhancers and promoter elements for achieving persistent transgene expression in the liver. The liver specific enhancer elements may be derived from either the human serum albumin, prothrombin, α-1microglobulin or aldolase genes in single copies or in multimerized form linked to elements derived from the cytomegalovirus intermediate early (CMV), α-1-antitrypsin or albumin promoters. In a preferred embodiment of the invention, an adenoviral vector comprising a liver specific enhancer/promoter combination operably linked to a transgene is administered to recipient cells. In other embodiments of the invention, adeno-associated viral vectors, retroviral vectors, lentiviral vectors or a plasmid comprising the liver specific enhancer/promoter combination linked to a transgene is administered to recipient cells. Also within the scope of the invention are promoter elements derived from the human prothrombin gene and the β-fibrinogen gene.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation of U.S. patent application Ser. No. 13/165,180, filed Jun. 21, 2011, and claims priority to U.S. Provisional Patent Application No. 61/359,667, filed Jun. 29, 2010, both of which are incorporated by reference in their entirety.
BACKGROUND
[0002] Field of the Invention
[0003] The present invention generally relates to making payments using mobile devices, and more particularly, to using the mobile device to intelligently make payments.
[0004] Related Art
[0005] Electronic payments are becoming a preferred method of payment because they offer advantages to the user not present with traditional physical payments. With a physical payment, the user is required to carry the funding instrument and present the funding instrument when ready to make a payment. Examples of physical funding instruments include cash, checks, credit cards, debit cards, coupons, gift certificates, gift cards, and the like. These can take up space in a user pocket, purse, or wallet. To reduce space, the consumer may not carry all funding instruments all the time, resulting in the possibility that a desired funding instrument is not available when the consumer is ready to use it at a point of sale (POS). Such physical funding instruments may also be lost or stolen. Thus, physical “wallets” can be cumbersome, inconvenient, and prone to loss.
[0006] To remedy this, mobile devices have been and are being used to make payments through payment providers, such as PayPal, Inc. of San Jose, Calif. Such payment providers typically allow a consumer to make a payment through the user's mobile device, such as through the use of barcodes, communication between the payment provider and the merchant, and other methods. After authentication and/or authorization, the payment is made through a user account with the payment provider, where the account is funded through a funding source, such as the user's bank or credit card. The funding source is typically a single default source selected by the user.
[0007] While this may allow the consumer to forego carrying credit cards, bank cards, and cash, the user must still decide whether to use the payment provider service, another payment service on the mobile device, or a physical funding instrument. This can be disadvantageous, which also applies to physical wallets, because the user must decide which of the many possible funding instruments to use for a particular purchase. This may result in the user choosing a payment instrument that is not the “best” choice for the transaction.
[0008] Therefore, a need exits for a payment solution that overcomes the disadvantages described above with conventional payment methods.
SUMMARY
[0009] According to one embodiment, a consumer has an account with a payment provider, such as PayPal, Inc. The account includes at least one funding source, and preferably several. When the user is ready to make a purchase or payment, such as at a point of sale, the payment provider selects what funding source (e.g., Visa, AMEX, credit cards associated with different rewards programs, PayPal, bank account, coupons, gift cards, etc.) to use based on the transaction information, including the amount, type of purchase, merchant, location, etc. The selection can be based on user selected preferences, payment history of user, goals, preferred or incentivized payment sources of the merchant, or any combination of logic. For example, there may be discounts or other rewards at a certain store if a specific card is used, the user may want to primarily use a card to get sufficient reward points for a goal, the user may want to limit certain cards to a maximum monthly or transaction amount, an AMEX Hilton card may be selected for use at a Hilton hotel, etc.
[0010] This greatly reduces the time and effort for the user to decide which card or other funding instrument to use. This also helps the user make use of coupons, etc., as part of the funding.
[0011] The payment provider may also provide payment directly from a funding source to the merchant so that the recipient need not have an account with the payment provider. This may also apply when the user does not have a payment provider account.
[0012] According to another embodiment, different authentication or security levels are applied to different uses of the user device. For example, payments may require one type of authentication, while non-payments (such as information transfers or displays) may require another type of authentication. Within payments or non-payments, there may be additional different security levels. For example, higher security may be required for higher payment amounts and use or display of more sensitive information, such as social security number, credit card number, and the like.
[0013] These and other features and advantages of the present invention will be more readily apparent from the detailed description of the embodiments set forth below taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE FIGURES
[0014] FIG. 1 is a flowchart showing a process a payment provider performs to process a payment from a user's smart wallet, according to one embodiment;
[0015] FIG. 2 is a flowchart showing a process for using a user mobile device as a digital wallet with different authentication levels according to one embodiment;
[0016] FIG. 3 is block diagram of a networked system suitable for implementing the process described herein according to an embodiment;
[0017] FIG. 4 is a block diagram of a computer system suitable for implementing one or more components in FIG. 3 according to one embodiment; and
[0018] FIGS. 5A-5D are exemplary flows with sample screen shots showing various flows using a smart wallet according to one embodiment.
[0019] Embodiments of the present disclosure and their advantages are best understood by referring to the detailed description that follows. It should be appreciated that like reference numerals are used to identify like elements illustrated in one or more of the figures, wherein showings therein are for purposes of illustrating embodiments of the present disclosure and not for purposes of limiting the same.
DETAILED DESCRIPTION
[0020] According to various embodiments, a smart digital wallet in a user's mobile device provides the user with recommendations or decisions on what funding instruments to use based on transaction information, user preferences, user history, and/or funding instrument information. The smart wallet may also be customized with different levels of security for making a payment, based in part on user preferences, transaction amount, location, and other factors. Thus, the user's mobile device can be used as a smart wallet to replace physical funding instruments, while providing numerous advantages not available with a physical wallet.
[0021] FIG. 1 is a flowchart showing a process 100 a payment provider performs to process a payment from a user's smart wallet, according to one embodiment. At step 102 , the payment provider receives an indication that the user is ready to make a payment for items. Items, as used herein, may include physical goods, digital goods, services, donations, and anything that the user is making a payment for, to, or regarding. In this embodiment, the user is at a physical location or point of sale (POS) for the payment, such as at a store. In other embodiments, the user may be shopping online and making the payment through a computing device, such as a PC.
[0022] The indication may be received in any number of ways. One example is the user accessing a payment app a user mobile device at the POS, which makes a call to the payment provider through the mobile device. The use may enter credentials to access the user's account and enable payment through the mobile device. Another example is the merchant communicating a purchase transaction to the payment provider at the POS through a merchant device. These can be when the user begins a checkout process, during a checkout process, or after all items have been scanned and totaled. In one embodiment, the minimum information communicated at step 102 is a desire for the user to make a payment and user identity/account information. The latter allows the payment provider to access the user's account and data associated with the account.
[0023] Once the user's account is accessed, the payment provider determines, at step 104 , if there are any default settings to the user's account for payments. Default settings may be determined by the user, such as user defined preferences, by the payment provider, such as based on payment history, or a combination of the two. Default settings include information about the use of funding instruments associated with the user account. For example, the user may have an American Express Hilton Reward credit card, a Citibank debit card or bank account, a Visa Southwest Airlines Reward credit card, and a Visa gift card as some of the funding sources for the user account. The AMEX card may be the main funding source, followed by the Visa gift card, and others in a particular order. So, with a purchase, the AMEX card would be the preferred funding instrument. However, there may be situations where the AMEX card cannot be used, such as at merchants/sites/locations where AMEX is not accepted, the AMEX card is rejected (such as expired, limit reached, fraud suspected, etc.). If the AMEX is unavailable for use, the Visa gift card would be the next choice. However, the Visa gift card may be unavailable because its value has been depleted. The next funding instrument would then be tried.
[0024] The default settings may be changed as needed. For example, the AMEX card may be the first choice because the user wants to accumulate Hilton points for an upcoming vacation stay. However, once enough points are accumulated or no longer needed, the user may replace the AMEX card with the Visa card so that the user can accumulate points quicker for free flights. Such changes may be made by the user through the user's account page with the payment provider.
[0025] If there are default settings, those settings are applied at step 106 . The system also determines, at step 108 , whether there are any location-based restrictions or rules for any of the user's funding instruments. For example, a certain gift card or coupon may only be used within the United States. Another coupon may only be used in California. The Visa gift card may be used anywhere, but may have a bonus if used in Arkansas. The bonus may be a 10% credit on the gift card. The Arkansas use may be Visa wanting more spending in Arkansas to help the Arkansas economy in wake of its recent earthquake.
[0026] If there is at least one location-based rule, a location of the user (or POS) is determined at step 110 . This may be through a location service or function associated with the user's mobile device. Thus, when the user is ready to make a payment, the user's location will be known through the user's mobile device. Typically, the location is at the POS. The user location may also be determined in other ways. One example is the merchant communicating the identity of the user to the payment provider, which informs the payment provider that the user is with the merchant, where the merchant location is known by the payment provider. The payment provider applies the one or more location-based rules at step 112 . This may include changing the priority of the user defined preferences accordingly.
[0027] The system receives, at step 114 , transaction details, which can be through the merchant or the user. Transaction details may include information about the items scanned or to be purchased, such as description, type, quantity, and price, merchant information, such as name, account number, main address, local store address, phone number, the transaction date, and the like, and amount of the transaction, including taxes and any discounts/coupons/rewards applied or to be applied.
[0028] Using this and any other applicable information, the “best” one or more funding instruments are determined, at step 116 , for the user to use in the present transaction. The determination may include processing all or a portion of the information available and received about the user, the merchant, the location, and the transaction. For example, a particular merchant may only accept certain funding instruments (such as Visa and MasterCard only for credit cards), not accept certain funding instruments (such as no American Express or coupons), and/or provide a reward or other incentive for using a particular funding instrument (such as a store branded credit card).
[0029] In another example, a particular coupon or gift card may be applicable to one or more purchases in the transaction. Such coupons or gift cards may then be selected for use. Certain coupons, gift cards, and the like may have upcoming expiration dates. Based on the date of the transaction and the expiration dates of applicable funding instruments, appropriate funding instruments may be selected to be used for this transaction. For example, funding instruments about to expire may be prioritized over later-expiring funding instruments.
[0030] Once funding instruments are selected for the current transaction, the user may be presented with the selection(s), at step 118 , on the user's mobile device. The user may see where each funding instrument is to be applied and how, along with amount applied if appropriate. For example, a certain purchase or item may only allow a certain dollar amount to from a gift card, voucher, or coupon to be applied to the purchase.
[0031] Next, the payment provider makes a determination, at step 120 , whether the user has confirmed the selected funding instruments. This determination may include receiving an electronic signal from the user device of a confirmation resulting from the user tapping or otherwise selecting a “confirm” or similar link/button on the device. If a confirmation is received, the transaction may be processed, at step 122 , with the selected funding instruments. Processing may be through the payment provider, where the payment provider receives payment details through the user device or the merchant, determines whether one or more payments can be approved, debiting user account(s) and crediting merchant account(s) immediately or at a later time, and sending a notification to the user and/or the merchant that the payment for the transaction has been approved or denied. Processing may also be directly through the user. For example, the user may simply present a physical credit card, where processing is through conventional credit card processing with the merchant.
[0032] If the user does not confirm the selected funding sources, the user may decide to revise the selection, such as adding one or more different funding sources, deleting one or more funding sources, or applying a funding source differently (e.g., using a lesser amount of a gift card). For example, even though the payment provider selected the AMEX card based on the user's previously set preference (the user had wanted to accumulate hotel points), the user may no longer need the points. This may be due to the user obtaining a sufficient amount of points, the hotel stay changed, or other reasons. The user also may not have changed user preferences yet. As a result, the user may replace the AMEX card with the Visa card.
[0033] In one embodiment, the user can revise selected funding instruments through the user device. For example, the user may select a funding for revision. The selected funding source may be deleted or otherwise revised accordingly, such as through user actions through the user device. A new funding source may be added, such as by selecting from a list of available funding sources. The list can be in any form and accessed through any number of ways, including a drop down menu or a new window on a browser or app.
[0034] After one or more revisions to the selected funding sources are made by the user, the revisions are communicated to and received by the payment provider at step 124 . Once received, the payment provider may transmit the user-revised payment instrument selections to the user at step 126 . The user may view the revised payment selections, such as on the user device, and confirm or revise again as needed using the steps described above. When the user confirms the payment instruments, the payment can be processed at step 122 .
[0035] Note that the various steps and decisions above may be performed in different sequences and select ones may be omitted, as well as additional steps and decisions added.
[0036] Thus, the user is able to use the “best” funding instruments to pay for a transaction using selections from the payment provider based on user set preferences, location, transaction details, merchant, date, and other factors. Payment can be made through the user's mobile device, thereby eliminated the need for the user to carry physical funding instruments like cash, credit cards, debit cards, checks, coupons, and gift cards.
[0037] FIG. 2 is a flowchart showing a process 200 for using a user mobile device as a digital wallet with different authentication levels according to one embodiment. A typical physical wallet may contain non-payment cards, such as medical insurance cards, frequent flyer numbers, hotel loyalty numbers, social security card, auto club card, and the like, in addition to funding instruments like those discussed above. A mobile device, such as smart phone or tablet, may be able to store such personal information of the user, such that the mobile device can become more like a physical wallet in that it can then contain both payment instruments and user information.
[0038] To use the mobile device for payment, the user typically is required to enter a password or PIN and a user/device identifier, such as a user name, email address, or phone number, unless the user/device identifier is automatically communicated to the payment provider through the mobile device. This can be time-consuming and cumbersome, especially with the small physical and virtual keypads associated with mobile devices. However, such authentication is needed to protect the funding instruments and prevent unauthorized users to make payments from the user's account.
[0039] There may be other data or functions in the phone that do not require the authentication levels of payments. For example, a frequent flyer number or transmitting of a frequent flyer number may not require the level of security as sending a payment. Other information, such as the user's social security number, may require additional security. Even payments may allow different levels of security. For example, a payment transaction of less than $20 may not require as much security as a payment transaction of greater than $200. Thus, FIG. 2 illustrates an example of how a mobile device or user of the mobile device may be authenticated for different information or transactions using the mobile device.
[0040] At step 202 , a determination is made whether the mobile device, for the current use, is to be used for payment. Payment transactions typically will require stronger authentication. The determination may include receiving an indication from the user through the mobile device, such as selecting a payment app, or from a recipient, such as a seller, through a recipient device identifying the user or payer. If the mobile device will be used for a payment transaction, a determination is made, at step 204 , whether the amount of the payment transaction will be greater than a certain amount, X. This amount can be set by the user or the payment provider. Higher amounts typically will require stronger authentication. The amount can include use of funds from the user's account with the payment provider, use of coupons, gift cards, vouchers, etc., and/or use of other funding sources such as credit cards.
[0041] If the anticipated payment amount is less than or equal to X, the payment provider may require the user to authenticate using a first authentication level, Auth1, at step 206 . Auth1 may simply require the user to unlock the mobile device or access a payment app. If the anticipated payment amount is greater than X, the user may be required, at step 208 , to authenticate through a second authentication level, Auth2, which is stronger than Auth1. An example of Auth2 may include entry of a user PIN, biometric information, a password, or other data, in addition to what was required at step 206 .
[0042] If, as determined, at step 202 , the current transaction is not for payment, a determination may be made, at step 210 , whether the transaction involves “sensitive” or “confidential” information. Examples of sensitive information may include the user's social security number, a bank account number, a password, credit card numbers including security codes, debit card numbers, etc. Examples of non-sensitive information stored in the mobile device may include account numbers for airline loyalty programs, hotel loyalty programs, merchant loyalty programs, and the like, medical insurance policy number, dental insurance policy number, AAA membership number, etc. The user may determine which information is sensitive and which is not, such as by designating specific data or types of data.
[0043] At step 212 , the user is required to authenticate at a third authentication level, Auth3, when the transaction involves exposure or transmission of sensitive information. Auth3, in one embodiment, is a stronger authentication than Auth1, but weaker than Auth2. In another embodiment, Auth3 is the same as Auth2. Auth3 may include requiring the user to enter an identifier, such as an email address, phone number, or user name.
[0044] If the information is not sensitive, the user may be requested to authenticate using a fourth authentication level, Auth4, at step 214 . Auth4 may be the same as Auth1. In another embodiment, Auth4 is weaker than Auth1, Auth2, and Auth3. For example, Auth4 may include the user simply being able to use the mobile device, and thus effectively not requiring any authentication, just possession of the device.
[0045] Note that the above authentication levels are just examples and not limiting. For example, additional authentication levels may be employed. This may be due to more than two levels of authentication for a payment, with the different levels based on a plurality of transaction amount thresholds. Information may also be divided into more than two categories of just sensitive and non-sensitive. Furthermore, determinations, in addition to or in place of, whether the transaction is for a payment and whether the transaction involves sensitive information stored in the mobile device may be included.
[0046] After the specific authentication level is requested/required, the requested information is received, at step 216 , from the user, such as through the user mobile device. The information may be received by the user entering the requested information, such as through a keypad, keyboard, touch pad, touch screen, or other data input. Once received the information is processed by the payment provider, at step 218 . Processing may include determining if the received information is what was requested and whether the received information was what was expected. This can be through accessing the user's account and checking authentication information of the user.
[0047] A determination is then made, at step 220 , whether the user can be authenticated. This determination may include typical authentication procedures for the payment provider, including any fraud analysis, account restrictions, transaction limits, etc.
[0048] If the user is authenticated, the transaction moves forward at step 222 . The transaction can proceed with a payment process, a communication, display or access of data/information, or other use of the mobile device. However, if the user authentication fails, the transaction may not be allowed to proceed until the user is authenticated. Thus, the payment provider may allow the user one or more additional attempts to authenticate, using the same authentication requests or something different. For example, the user may be asked a security question.
[0049] Accordingly, the payment provider (and/or the user) may set different levels of security to be linked on the access to the wallet or some part of the wallet. As an example, the user may not care about protecting coupons or some loyalty components (e.g., frequent flyer card or movie theater reward card), but will care about protecting credit cards or payment instruments. The basic default security settings of the wallet may be speed of transaction over higher security (resulting in more friction or interaction from the user). However, the “smarter” the wallet will be, the better security with little user interaction can be provided by the payment provider.
[0050] For an example, a user could decide that for any transaction, the user does not want to be asked anything. As long as the smart wallet is triggered properly, the transaction will go through. Some users, being more cautious, may want to see any transaction and will ask to be prompted for information of transactions going through the smart wallet. Other users, wanting more security, could decide to be prompted for an actual validation of the transaction by entering a PIN, a password or a fingerprint/biometric component. The level of security could be linked also to the amount of the transaction, as mentioned above. For example, under $20, no action required, between $20 and $50, get a prompt to inform the user, above $50, enter a PIN. These levels could be flexible and decided by the user but again, with a validation/association to the risk profile managed by the payment provider.
[0051] Thus, using the above, a user may have multiple security choices when setting up the user's mobile device and using the mobile device for different transactions or uses. This can provide a more frictionless user experience by not requiring the user to enter passwords/PINs or biometric information for all uses of the phone. Multiple security choices can also protect the user from fraudulent uses of the mobile device by requiring heightened or stronger authentication for higher payments or access to extremely sensitive information.
[0052] There may be several components to such a digital wallet described above, including a user profile, a risk profile, and stored value. A user may create a user profile for the smart wallet. Typically, the more information the user provides, the “smarter” the wallet. The payment provider can use this information to make a more informed decision on funding instruments for each transaction. Examples of what the user may enter into the profile include spending preferences, spending limits, goals, preferred funding instruments, etc. The user profile may be revised by the user, such as by revising profile information. The profile may also be revised by the payment provider, such as based on user transactions. For example, if the user continues to revise funding instruments suggested or presented by the payment provider, the payment provider may revise the user profile accordingly to reflect the user preferences.
[0053] Another component, the user's risk profile, may be based in part on parameters or information from the payment provider. For example, a long time user of the payment provider service with a verified address and payment instruments (e.g., a bank account linked and verified to the user's payment provider account) will have a better risk profile than a user who just registered and has not linked/verified any bank account to his account. Other elements that may be used to build a user risk profile include the make/model of the user's mobile device (e.g., if it is registered with the payment provider (phone number but also hardware/software configurations, browser, etc.)). While the main risk profile may be stored in the cloud, a subset version could be stored on the mobile device with a specific set of parameters, especially for “offline” transactions using a stored value.
[0054] Stored value is an amount of cash the user maintains as a balance with the payment provider for payments. The payment provider may create an “extrapolation” of this balance on the mobile device of the user. This stored value may be linked to the risk profile of the user. For example, if a user with an excellent risk profile has a $500 balance on his payment provider account, then the payment provider may grant the user access to a stored value of $400 or even $500. A new user to the payment provider with an unverified account may have a $500 account balance with the payment provider, but would be allowed to have a stored value emergency access of only $5 or $50 or whatever amount would be deemed to be an acceptable risk for the payment provider for that user.
[0055] In one embodiment, the payment provider maintains a dynamic stored value management system that will rely on the capacity to enforce a verification of stored value spending against the balance remaining in the cloud. With data based on the mobile device, the payment provider could feed back in real time the stored value spending history against the account balance on a constant basis. However, for some mobile devices with limited functions or for a mobile device going on low battery mode, the payment provider may not be able to feed back this history and will have to grant a level of access in an offline/off the cloud mode. In one example, a user is trying to catch the last subway and the user's mobile device is NFC-enabled, but the battery is almost depleted. However, a contactless reader from the subway company is set to power up the NFC chip on the user device and provide enough energy boost in a short period of time to retrieve a ticket and/or payment to grant access through the gate. At that point, the payment provider may not have the option to provide feedback for any verification to the cloud, but the “smart wallet” will be able to provide the needed funds offline (and register it in the transaction history log for future synchronization). By doing so, the payment provider is taking the risk but also making sure the user experience is on par with the user expectations or online payment transactions.
[0056] The payment provider may manage offline transactions from an offline transaction history log applied against the stored value balance. However, based on the risk profile, the payment provider may associate parameters to this function of the smart wallet, such as number of transaction, transaction amount, time offline, etc. and force back a connection to the cloud to update the smart wallet and the stored value balance.
[0057] In order to manage the user and risk profiles, as well as matching data to trigger some functions of the smart wallet (e.g., user location, user preference from that specific handset, transaction log history, etc.), a back-end module may be in charge of the “smart” or intelligence in the smart wallet. This could be managed by components that are part of the payment provider system. By doing so and creating this “intermediate” buffer, the payment provider can deliver a faster service towards the mobile device and manage the stored value better against the risk profile but also provide a needed protection/isolation of the main user account residing in the payment provider core system.
[0058] From a technical point of view, the wallet may be an application residing on the mobile device and linked to the payment provider wallet in the cloud. Some components of the wallet (e.g., user interfacing) could be normal applications such as Java applet, widget or native type. However security functions (anti-phishing, anti-spoofing mechanisms, etc.) may need to be disassociated from the basic function and be launched from a “trusted” element/component on the mobile device. This could be a hardware and/or a software component. Examples of such components include TrustZone from ARM, Embedded Secure Element, MicroSD Card or SIM card. In one embodiment, the smart wallet or account remains in the cloud at all times and the mechanism to protect it are never exposed to the user or mobile device. For this reason, the user and risk profiles are managed differently.
[0059] The following provides one example of a smart wallet use case. A Costco customer has an American Express Costco branded card. He also goes on a regular basis to a Costco store located near his home. By monitoring the payment history of this user in that store/merchant, the payment provider will know that the user pays 90% of the time with this Amex card. The 10% remaining are payments made with a debit card. Both instruments are registered with the user's payment provider account.
[0060] By using the smart wallet (and assuming the store or merchant is known by the payment provider or the payment provider has created a business addresses register), the user may then have his default payment instrument proposed to him as follows: 1) Payment instrument #1 (preferred): American Express Costco card; 2) Payment Instrument #2 (secondary): Debit card; 3) Payment Instrument #3 (Stored value): Payment Provider Balance extension in physical world. The user may edit or revise as desired.
[0061] This selection will be triggered by the user profile, his specific location (leverage from the GPS position) and (if enabled) a store “wireless” signal sent to the mobile device of the user and “read” by the smart wallet (e.g., through an NFC tag, Bluetooth (existing pairing) or other). By doing triangulation of data, the smart wallet may be able to enhance the choice of payment instruments.
[0062] When the user arrives at the cash register, he connects to the payment provider, such as through an NFC channel, a remote/online session, etc. Transaction information, such as amount, store, merchant, type of purchase, etc., is communicated to the payment provider, as well as the location of the user and/or POS and any other information needed by the payment provider. The payment provider accesses the user's account and preferences and decides which funding instrument or combination of funding instruments to use automatically.
[0063] FIG. 3 is a block diagram of a networked system 300 configured to handle a transaction using a smart wallet, such as described above, in accordance with an embodiment of the invention. System 300 includes a user device 310 , a merchant server 340 , and a payment provider server 370 in communication over a network 360 . Payment provider server 370 may be maintained by a payment provider, such as PayPal, Inc. of San Jose, Calif. A user 305 , such as a sender or consumer, utilizes user device 310 to perform a transaction using payment provider server 370 . Note that transaction, as used herein, refers to any suitable action performed using the user device, including payments, transfer of information, display of information, etc.
[0064] User device 310 , merchant server 340 , and payment provider server 370 may each include one or more processors, memories, and other appropriate components for executing instructions such as program code and/or data stored on one or more computer readable mediums to implement the various applications, data, and steps described herein. For example, such instructions may be stored in one or more computer readable media such as memories or data storage devices internal and/or external to various components of system 300 , and/or accessible over network 360 .
[0065] Network 360 may be implemented as a single network or a combination of multiple networks. For example, in various embodiments, network 360 may include the Internet or one or more intranets, landline networks, wireless networks, and/or other appropriate types of networks.
[0066] User device 310 may be implemented using any appropriate hardware and software configured for wired and/or wireless communication over network 360 . For example, in one embodiment, the user device may be implemented as a personal computer (PC), a smart phone, personal digital assistant (PDA), laptop computer, and/or other types of computing devices capable of transmitting and/or receiving data, such as an iPad™ from Apple™.
[0067] User device 310 may include one or more browser applications 315 which may be used, for example, to provide a convenient interface to permit user 305 to browse information available over network 360 . For example, in one embodiment, browser application 315 may be implemented as a web browser configured to view information available over the Internet, including accessing a loyalty site. User device 310 may also include one or more toolbar applications 320 which may be used, for example, to provide client-side processing for performing desired tasks in response to operations selected by user 305 . In one embodiment, toolbar application 320 may display a user interface in connection with browser application 315 as further described herein.
[0068] User device 310 may further include other applications 325 as may be desired in particular embodiments to provide desired features to user device 310 . For example, other applications 325 may include security applications for implementing client-side security features, programmatic client applications for interfacing with appropriate application programming interfaces (APIs) over network 360 , or other types of applications. Applications 325 may also include email, texting, voice and IM applications that allow user 305 to send and receive emails, calls, and texts through network 360 , as well as applications that enable the user to communicate, transfer information, make payments, and otherwise utilize a smart wallet through the payment provider as discussed above. User device 310 includes one or more user identifiers 330 which may be implemented, for example, as operating system registry entries, cookies associated with browser application 315 , identifiers associated with hardware of user device 310 , or other appropriate identifiers, such as used for payment/user/device authentication. In one embodiment, user identifier 330 may be used by a payment service provider to associate user 305 with a particular account maintained by the payment provider as further described herein. A communications application 322 , with associated interfaces, enables user device 310 to communicate within system 300 .
[0069] Merchant server 340 may be maintained, for example, by a merchant or seller offering various products and/or services in exchange for payment to be received over network 360 . Merchant server 340 may be used for POS or online purchases and transactions. Generally, merchant server 340 may be maintained by anyone or any entity that receives money, which includes charities as well as retailers and restaurants. Merchant server 340 includes a database 345 identifying available products and/or services (e.g., collectively referred to as items) which may be made available for viewing and purchase by user 305 . Accordingly, merchant server 340 also includes a marketplace application 350 which may be configured to serve information over network 360 to browser 315 of user device 310 . In one embodiment, user 305 may interact with marketplace application 350 through browser applications over network 360 in order to view various products, food items, or services identified in database 345 .
[0070] Merchant server 340 also includes a checkout application 355 which may be configured to facilitate the purchase by user 305 of goods or services identified by marketplace application 350 . Checkout application 355 may be configured to accept payment information from or on behalf of user 305 through payment service provider server 370 over network 360 , such as using selected funding instruments from the smart wallet. For example, checkout application 355 may receive and process a payment confirmation from payment service provider server 370 , as well as transmit transaction information to the payment provider and receive information from the payment provider (e.g., a transaction ID).
[0071] Payment provider server 370 may be maintained, for example, by an online payment service provider which may provide payment between user 305 and the operator of merchant server 340 . In this regard, payment provider server 370 includes one or more payment applications 375 which may be configured to interact with user device 310 and/or merchant server 340 over network 360 to facilitate the purchase of goods or services, communicate/display information, and send payments by user 305 of user device 310 and as discussed above.
[0072] Payment provider server 370 also maintains a plurality of user accounts 380 , each of which may include account information 385 associated with individual users. For example, account information 385 may include private financial information of users of devices such as account numbers, passwords, device identifiers, user names, phone numbers, credit card information, bank information, or other financial information which may be used to facilitate online transactions by user 305 . Advantageously, payment application 375 may be configured to interact with merchant server 340 on behalf of user 305 during a transaction with checkout application 355 to track and manage purchases made by users and which funding sources are used, as well as points for a user.
[0073] A transaction processing application 390 , which may be part of payment application 375 or separate, may be configured to receive information from a user device and/or merchant server 340 for processing and storage in a payment database 395 . Transaction processing application 390 may include one or more applications to process information from user 305 for processing an order and payment using various selected funding instruments as described herein. As such, transaction processing application 390 may store details of an order associated with a phrase from individual users. Payment application 375 may be further configured to determine the existence of and to manage accounts for user 305 , as well as create new accounts if necessary, such as the set up, management, and use of a smart wallet for the user/mobile device.
[0074] FIG. 4 is a block diagram of a computer system 400 suitable for implementing one or more embodiments of the present disclosure. In various implementations, the user device may comprise a personal computing device (e.g., smart phone, a computing tablet, a personal computer, laptop, PDA, Bluetooth device, key FOB, badge, etc.) capable of communicating with the network. The merchant and/or payment provider may utilize a network computing device (e.g., a network server) capable of communicating with the network. It should be appreciated that each of the devices utilized by users, merchants, and payment providers may be implemented as computer system 400 in a manner as follows.
[0075] Computer system 400 includes a bus 402 or other communication mechanism for communicating information data, signals, and information between various components of computer system 400 . Components include an input/output (I/O) component 404 that processes a user action, such as selecting keys from a keypad/keyboard, selecting one or more buttons or links, etc., and sends a corresponding signal to bus 402 . I/O component 404 may also include an output component, such as a display 411 and a cursor control 413 (such as a keyboard, keypad, mouse, etc.). An optional audio input/output component 405 may also be included to allow a user to use voice for inputting information by converting audio signals. Audio I/O component 405 may allow the user to hear audio. A transceiver or network interface 406 transmits and receives signals between computer system 400 and other devices, such as another user device, a merchant server, or a payment provider server via network 360 . In one embodiment, the transmission is wireless, although other transmission mediums and methods may also be suitable. A processor 412 , which can be a micro-controller, digital signal processor (DSP), or other processing component, processes these various signals, such as for display on computer system 400 or transmission to other devices via a communication link 418 . Processor 412 may also control transmission of information, such as cookies or IP addresses, to other devices.
[0076] Components of computer system 400 also include a system memory component 414 (e.g., RAM), a static storage component 416 (e.g., ROM), and/or a disk drive 417 . Computer system 400 performs specific operations by processor 412 and other components by executing one or more sequences of instructions contained in system memory component 414 . Logic may be encoded in a computer readable medium, which may refer to any medium that participates in providing instructions to processor 412 for execution. Such a medium may take many forms, including but not limited to, non-volatile media, volatile media, and transmission media. In various implementations, non-volatile media includes optical or magnetic disks, volatile media includes dynamic memory, such as system memory component 414 , and transmission media includes coaxial cables, copper wire, and fiber optics, including wires that comprise bus 402 . In one embodiment, the logic is encoded in non-transitory computer readable medium. In one example, transmission media may take the form of acoustic or light waves, such as those generated during radio wave, optical, and infrared data communications.
[0077] Some common forms of computer readable media includes, for example, floppy disk, flexible disk, hard disk, magnetic tape, any other magnetic medium, CD-ROM, any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes, RAM, PROM, EEPROM, FLASH-EEPROM, any other memory chip or cartridge, or any other medium from which a computer is adapted to read.
[0078] In various embodiments of the present disclosure, execution of instruction sequences to practice the present disclosure may be performed by computer system 400 . In various other embodiments of the present disclosure, a plurality of computer systems 400 coupled by communication link 418 to the network (e.g., such as a LAN, WLAN, PTSN, and/or various other wired or wireless networks, including telecommunications, mobile, and cellular phone networks) may perform instruction sequences to practice the present disclosure in coordination with one another.
[0079] Where applicable, various embodiments provided by the present disclosure may be implemented using hardware, software, or combinations of hardware and software. Also, where applicable, the various hardware components and/or software components set forth herein may be combined into composite components comprising software, hardware, and/or both without departing from the spirit of the present disclosure. Where applicable, the various hardware components and/or software components set forth herein may be separated into sub-components comprising software, hardware, or both without departing from the scope of the present disclosure. In addition, where applicable, it is contemplated that software components may be implemented as hardware components and vice-versa.
[0080] Software, in accordance with the present disclosure, such as program code and/or data, may be stored on one or more computer readable mediums. It is also contemplated that software identified herein may be implemented using one or more general purpose or specific purpose computers and/or computer systems, networked and/or otherwise. Where applicable, the ordering of various steps described herein may be changed, combined into composite steps, and/or separated into sub-steps to provide features described herein.
[0081] The foregoing disclosure is not intended to limit the present disclosure to the precise forms or particular fields of use disclosed. As such, it is contemplated that various alternate embodiments and/or modifications to the present disclosure, whether explicitly described or implied herein, are possible in light of the disclosure. Having thus described embodiments of the present disclosure, persons of ordinary skill in the art will recognize that changes may be made in form and detail without departing from the scope of the present disclosure. Thus, the present disclosure is limited only by the claims.
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Systems, methods, and computer program products for providing cloud-based application security are disclosed. For example, a server part of a cloud-based application may determine a plurality of security challenges for authorizing a request based on a plurality of security settings of a user account and one or more attributes of the request, issue a first-level authorization challenge and a second-level authorization challenge based on the determining, identify a plurality of available resources from the user account for the request, and responsive to successful completion of the first-level authorization challenge and the second-level authorization challenge, automatically apply two or more of the available resources from the user account to fulfill the request based on the one or more attributes of the request and a physical location associated with the request.
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BACKGROUND OF THE INVENTION
The present invention relates to the monitoring of lengths of hose and is particularly applicable to the monitoring of flexible heavy duty hoses used to transfer oil at sea. Such hoses are known as fluid transport hoses.
It is often necessary to load and discharge crude oil at sea due to problems of berthing large ocean going tankers alongside shore facilities in shallow waters.
A Single Buoy Mooring system is generally used for this purpose where for example oil is conveyed through steel sub surface pipelines from onshore storage or pumping facilities to a point on the sea bed under the surface floating buoy.
Flexible submarine hoses connect from the fixed pipeline via the buoy through floating hoses on the surface to a "pick-up" point which is connected, as required, to the tanker manifold. Both the submarine and floating hose sections comprise individual sections bolted together as required.
It is a problem in such a system of loading and unloading tankers that in the event of one of the hose sections, of which there are several, breaking, oil will leak out and cause pollution. In order therefore to avoid environmental pollution, it is desirable to detect imminent leakage of oil from a hose section prior to its occurrence so as to enable the hose section to be replaced.
If ample warning is provided by the detection system there would be substantial savings in costly, and frequent hose inspection procedures, and the down time of the oil pumping apparatus may be kept to a minimum. That is to say to the time necessary for the physical replacement of the hose section.
If on the other hand leakage has already commenced, then the down time will necessarily be significantly longer coupled with the risk of penalties imposed by third parties.
SUMMARY OF THE INVENTION
With a view to enabling early detection of imminent breakdown of a hose section, the present invention in one aspect provides a fluid transport hose having two or more plies comprising a sensing element located between the plies of the hose, the sensing element being responsive to the electromagnetic properties of fluid present between the plies as a result of a failure of an inner ply of the hose.
It is believed that in some cases of rupture, the mechanism involves initially the formation of a mushroom or bubble in or along the inner ply of the hose, deforming the inner wall of the hose in a manner to obstruct the flow of oil. This obstruction will result in considerable heat generation and eventually in the tearing of the mushroom from the inner ply of the hose. Such a fault presents the problem that once the inner ply has ruptured, the extent of leakage is such that the outer plies cannot contain the leakage for much longer. It is therefore desirable in such forms of rupture to detect the fault prior to seepage of oil between the plies.
In accordance with a second aspect, the invention provides a fluid transport hose having two or more plies comprising a sensing element located between the plies, the sensing element being adapted to respond to the failure of an inner ply of the hose by presenting an open circuit.
Preferably, the sensing element is comprised of a coil of fine wire wrapped around the inner ply and connected to means which are responsive to a change in the electrical impedance of the coil. In the event of oil seepage, the inductance of the coil will be changed by virtue of the change in the magnetic properties of the material immediately contacting the coil and in the event of deformation of the inner plies this will change the inductance of the coil but may additionally cause rupture of the coil resulting in an open circuit.
Alternatively, however, the sensing element may be in the form of parallel non-touching wires connected to means responsive to a change in conductance between the individual wires or to a change in the capacitance between the wires.
If desired, the sensing element may be in the form of conductors printed onto a flexible backing which is wrapped between the plies or may comprise similarly disposed sheets of aluminium foil.
In a further alternative form the sensing element may comprise a magnetic tape connected to means responsive to a change in a radio frequency signal carried by the magnetic tape.
When considering the detection of deformation of an inner ply of a hose, a further advantageous embodiment of the sensing element involves the use of a fibre optic element.
If desired, a sensing element may additionally be installed between the outermost plies of the hose in order to sense physical damage to the outer plies of the hose as caused for example by collision with a vessel.
BRIEF DESCRIPTION OF DRAWINGS
The invention will now be described further, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 illustrates a ship moored at a buoy and connected to the buoy by means of an oil transfer pipe built of several flanged hose sections,
FIGS. 2 and 3 show a section of a hose forming part of the pipeline shown in FIG. 1, the hose section being cut away to illustrate the composite structure of the hose, and
FIG. 4 shows a section of hose broken away to illustrate its composite structure and diagramatically illustrates a radio link between the hose and a monitoring unit.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIG. 1, there is shown a tanker 10 moored by a buoy 12. Oil is transferred from the tanker 10 to the buoy 12 through an oil transfer pipe 14 which is flexible and which may float in part. The oil is delivered to an onshore station via the submerged pipeline 16. The transfer pipe 14 is formed of individual hose sections 20 which are flanged at each end so that they may be joined together. The hose sections 20 must be flexible and yet capable of withstanding the harsh environment to which they are subjected. The hose sections 20 are of a composite structure and this is illustrated in FIG. 2. Each hose section 20 consists of a high grade synthetic rubber tube 22, a sensing element 24 which is in contact with the outer surface of the tube 22, a textile ply 26 impregnated and coated with synthetic rubber, an overlay 28 of plies of braided high tensile steel cable, a layer of synthetic rubber 30 in which helically wound steel wire 32 is embedded and an outer sheath of wear resistant material 34.
The sensing element 24 should be flexible enough to withstand distortions of the hose section caused by installation, operational manipulation and ambient sea conditions insofar as these do not result in damage to the hose. The flexibility of the sensing element 24 is of greater practical significance when the hose section is not provided with a reinforcing steel wire 32, such hose sections are becoming more common.
The sensing element 24 is comprised of a coil of fine wire wrapped around the tube 22 and connected to a sensing unit 42 which is responsive to a change in the electrical impedance of the coil. This embodiment of the sensing element 24 is particularly useful since it is responsive to the presence of oil between the plies and is also responsive to the deformation of the tube 22. In the event of oil seepage, the inductance of the coil 24 will be changed by virtue of the change in the magnetic properties of the material immediately contacting the coil 24 and in the event of deformation of the tube 22 this will change the inductance of the coil 24 but may additionally cause rupture of the coil 24 resulting in an open circuit. The coil 24 is positioned adjacent the tube 22 in order to provide an early indication that breakdown of the hose section 20 is imminent.
The sensing unit, which is responsive to a change in the electrical impedance of the coil 24, may comprise an inductive bridge circuit in which the inductance of the coil 24 is compared with a reference inductance. Alternatively, the inductance of the coil 24 may form part of a tuned circuit wherein the frequency of oscillation of the tuned circuit will vary in accordance with changes in the inductance of the coil 24. A further alternative is to arrange the inductance of the coil as part of a blocking oscillator circuit in which case the circuit responds when the inductance of the coil 24 reaches a threshold value. The sensing unit may be encapsulated between the plies of the hose.
A signal indicative of the imminent breakdown of the hose section 20 is produced by the coil 24 in combination with the sensing unit to which the coil 24 is connected. This signal is combined with a further signal, produced by additional circuitry, which identifies the specific hose section 20. The combined monitoring signal is relayed to a suitable receiving station 44 from which the entire length of the oil transfer pipe 14 may be kept under surveillance. The combined monitoring signal is preferably relayed to the receiving station by means of radio-transmission. The radio transmitter can be separate from or combined with the sensing unit and additional circuitry, in the case of the combination the circuits can be encapsulated and mounted on a flange at one end of the hose section 20.
Whilst the preferred form of the sensing element 24 is that of a coil of fine wire several advantageous variations exist. The characteristic of the sensing element 24 which is used to monitor the hose and the sensing unit responsive to variations of that characteristic are dependent upon the form of the sensing element and the form or forms of deterioration which are being relied upon to indicate imminent breakdown of the hose section 20.
When the sensing element 24 is primarily intended to be responsive to the seepage of oil between the plies of the hose section 20, the sensing element 24 may comprise several components the capacitance or conductance between which is used to monitor the hose section 20. The sensing element 24 may be in the form of parallel non-touching wires, as shown in FIGS. 2 and 4 which are connected to v sensing unit 42 responsive to a change in the conductance of the material disposed between the individual wires or to a change in the capacitance between the wires. Alternatively, the sensing element may be in the form of conductors printed onto a flexible backing sheet which is wrapped between the plies or may comprise similarly disposed sheets of aluminium foil. A further alternative embodiment of the sensing element 24 is the use of a magnetic tape 40 wrapped around or along the tube 22 as shown in FIG. 3. A radio frequency signal is continuously or periodically transmitted along the magnetic tape with known filtering and detection techniques being employed to determine when the transmission of the signal along the magnetic tape has been affected by the presence of oil between the plies of the hose due to seepage through or rupture of the tube 22.
It is advantageous to dispose particles 36 of a suitable material between the plies of the hose together with the sensing element. These particles become suspended in the fluid which flows between the plies as a result of rupture of the tube 22 and serve to enhance the change in the electromagnetic parameters to which the sensing element responds. The use of particles of carbon black is particularly advantageous in the case of a sensing unit responsive to a change in conductance between the conductors of a sensing element consisting of parallel non-touching wires. Other suitable materials include particles having strong magnetic or conductive properties such as ferrous oxide. Care should be taken to ensure that the adhesion between the plies of the hose is not significantly reduced by the presence of the particles between the plies.
All of the above mentioned forms of the sensing element 24 are also responsive, to varying degrees, to deformation and rupture of the tube 22. Rupture of the tube 22 will result in the sensing element 24 being broken which can be detected and thus used to monitor the hose. When detecting the deformation and rupture of the tube 22 an advantageous embodiment of the sensing element 24 involves the use of a fibre optic element. Rupture of the tube 24 will cause the fibre optic element to break and thus result in the fibre optic element being unable to transmit a signal. The use of a fibre optic element is advantageous due to the material from which it is manufactured and the methods by which it may be coupled to transducers, particularly when compared with the corresponding properties of electrically conducting elements.
Additional monitoring of the hose sections 20 may be provided in order to detect the occurrence of physical damage to the outer plies of the hose. Such damage can be caused by passing vessels sailing over the floating hose 14. The additional monitoring may be effected by the use of a secondary sensing element positioned between the layer of synthetic rubber 30 and the outer sheath 34. The secondary sensing element may take the form of any of the above described variations of the sensing element 24 which, in combination with the respective sensing unit, is capable of detecting changes in characteristics caused by physical damage to the outer plies of a hose section 20. The sensing element may be separate from or a continuation of the sensing element 24. The preferred form of the sensing element is a fibre optic element 38, which will produce an open circuit when damage occurs. Preferably, indication of damage to the outer plies of a hose section 20 is relayed to the receiving station by a unique code used within the signalling system described above.
An additional detection device in the form of a pressure sensitive switch may be provided on the hose sections and is particularly useful when used on the hose section which is unattached at one end when the pipeline is not connected to a tanker. The pressure sensitive switch produces a signal if the free end of the pipeline sinks to a critical depth, that is the depth at which the remainder of the floating hose begins to be dragged below the surface of the sea.
Several variations of the signalling system are possible. Imminent breakdown of the hose section 20 may be signalled solely by a visual signal transmitted from the hose section 20. Monitoring signals may be relayed to the receiving station by cable transmission. The hose sections 20 constituting the oil transfer pipe 14 may be grouped into sets with the transmission of monitoring signals being relayed from each set. The relay of monitoring signals to a receiving station by means of radio transmission may occur by means of several radio links between relay stations, one such relay station may conveniently be positioned on the buoy 12.
The apparatus can be arranged so that the condition of the hose sections 20 are under surveillance, are periodically and/or sequentially inspected or arranged so that a warning signal is produced only when breakdown of a hose section 20 is imminent.
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A fluid transport hose having two or more plies comprising a sensing element located between the plies, the sensing element being responsive to the electromagnetic properties of fluid between the plies as a result of a rupture of the inner ply. Alternatively, the sensing element may be adapted to respond to the failure of an inner ply of the hose by presenting an open circuit.
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CROSS REFERENCE TO RELATED PATENT
[0001] The present patent application is a continuation-in-part of my co-pending patent application Ser. No. 14/069,341 filed Oct. 31, 2013 and entitled “METHOD OF AND SYSTEM FOR INDUCING A PLANNED AVALANCHE”. The specification and drawings of that patent application, which is sometimes referred to as the “Tuning Patent”, are specifically incorporated herein by reference.
[0002] The Tuning Patent referenced above is a continuation-in-part patent application of my then co-pending patent application, Ser. No. 13/176,723 filed Jul. 5, 2011, entitled “AVALANCHE CONTROL SYSTEM AND METHOD”, issuing as U.S. Pat. No. 8,596,929 on Dec. 3, 2013. The specification and drawings of that patent, which is sometimes referred to as the “Avalanche Patent”, are specifically incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0003] Field of Invention:
[0004] The present invention is an improved method and system of inducing a planned (or controlled) avalanche in a region in which an uncontrolled avalanche of snow might occur. That is, a controlled avalanche may be induced at a time which is most convenient and as frequently as desired to avoid a large avalanche at an undesirable time.
BACKGROUND ART
[0005] Ski slopes, roadways, housing and railways through canyons are at risk of an uncontrolled avalanche in some areas. An avalanche can occur spontaneously when a snow pack is unstable and there is enough vertical angle. Areas where the instability is the greatest are known as avalanche “birthing” areas
[0006] Naturally occurring avalanches are somewhat predictable, yet uncontrollable. It is well known that earthquakes have caused several of history's great avalanches. Snowmobiles are risky to ride in avalanche-prone areas due to their propensity to initiate an avalanche.
[0007] Avalanches are also hazardous—every year a number of people are killed as a result of an avalanche, and more are injured as a result of an avalanche. While some of the injuries may be minor, other injuries are significant, making an uncontrolled avalanche something which should be avoided, to the extent possible.
[0008] Various approaches have been suggested to mitigate avalanche events. One approach has been to use a concussive event to trigger a controlled avalanche, for example, artillery ordinance, dynamite or a mortar shell. More recently, gas explosions in one of a variety of types have become popular. For example, a fixed concussive device using explosive gases is one such system for using a gas explosion to initiate an avalanche, while a “Daisy Bell” concussive device carried by a helicopter is another such device.
[0009] The use of ordinance requires special handling skills and is the subject of increased regulation due to safety concerns.
[0010] Some avalanche control systems do not work well during times of snowfall or other adverse weather situations, such as fog, such as those avalanche control systems which require a helicopter.
[0011] Some of the avalanche control systems are costly to use—for example, the Daisy Bell system requiring a helicopter and pilot.
[0012] Additionally, some of these prior art systems for creating an avalanche employ chemical compounds which are harmful (adverse) to the environment, including the water supply. Some of the chemicals which are released during use of those prior art avalanche control system release chemicals which are harmful to humans or animals when those chemicals become part f the water supply.
[0013] My previously-filed Avalanche Patent describes a system and method for causing a controlled avalanche. My Tuning Patent describes a method and system for setting up an avalanche-generating system and operating it at a desirable frequency based on the local environment of an installation, particularly the characteristics of ground in the area of mounting. However, neither patent describes a convenient source of available vibrating parts for use in assembling such an avalanche control system, nor does either patent (or the known prior art) address the effects of vibration on some of the components of the system described in the Avalanche Patent.
[0014] Accordingly, it will be appreciated that the prior art system for inducing an avalanche have undesirable disadvantages and limitations.
SUMMARY OF THE INVENTION
[0015] The present invention overcomes some of the disadvantages and limitation of the prior art systems for inducing a planned or controlled avalanche of snow in those areas which have been identified as prone to avalanche activity.
[0016] The present invention allows for creating many smaller and/or controlled avalanches to reduce the risk of a large, uncontrolled and unpredictable avalanche.
[0017] The present invention is “friendlier” to the environment in avoiding undesirable chemicals and inconveniently-timed avalanches which may jeopardize lives. Further, since an avalanche may close roadways and other accesses, it would be desirable to “schedule” such avalanches at a time which is convenient (like the middle of the night), rather than at a time of peak activity.
[0018] The present invention includes a method of setting up a vibrational system to induce a controlled avalanche at a desired time.
[0019] The present invention may also allow for the avalanche-inducing system to be “tuned” to a desired frequency to compensate for differences in the ground surrounding an avalanche birthing area. The tuning can also compensate for variations in the attachment of a vibration-inducing source with the surrounding ground.
[0020] The present system is also relatively inexpensive to use (and reuse) and provides a minimal environmental impact compared with alternate systems. It also has the advantage that it can be operated in almost any kind of weather, not being dependent on moving people or equipment to the site of the desired avalanche.
[0021] The present system also can use “recycled” parts from devices which have served other functions in the past—therefore it is not necessary to make or buy additional (new) parts. Some recreation areas use transportation products such as golf carts and then dispose of those products when they look “used” or “worn”, but while the operating structures remain reliable and in good working condition.
[0022] The present system and method also addresses the undesirable effects of vibration in an avalanche control apparatus and isolates some of the components (particularly some of the electrical components such as batteries and solar panels) from undesirable effects of vibration created by the avalanche causing structure. By mounting those electrical components separate from components having greatest vibration, those electrical components will enjoy a longer useful life and/or be more efficient.
[0023] Other objects and advantages of the present invention will be apparent to one of ordinary skill in the art in view of the following description of the invention, taken in combination with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a pictorial representation of an area of an avalanche-prone area, showing one arrangement of avalanche-triggering apparatuses and sensors;
[0025] FIG. 2 is an enlarged view of a portion of FIG. 1 , an avalanche-prone area of FIG. 1 ;
[0026] FIG. 3 is a perspective view of components (including a drive system) of the present invention;
[0027] FIGS. 4-6 are views of the drive system shown in FIG. 3 ;
[0028] FIGS. 7 and 8 are views of an electrical equipment mast useful in practicing the present invention; and
[0029] FIG. 9 is a flow chart illustrating an illustrative method of practicing the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0030] FIG. 1 shows a pictorial representation of a mountainous area 10 in which avalanches can be expected. The mountainous area 10 includes a plurality of peaks 12 , 14 and 16 , with an avalanche origin region 20 defined between the lines 14 a and 14 b delineating an avalanche-prone area. The avalanche origin region 20 (sometimes alternatively called an “avalanche-birthing” or “avalanche-prone” area) often has a substantial terrain slope, perhaps averaging approximately 40 degrees, and is located within a terrain area in which the slope of the terrain is generally more gentle. A plurality of vibration sources 30 are mounted within the avalanche prone area 20 in accordance with the present invention. These vibration sources 30 may be generally of the type described in the Avalanche Patent referred to above and incorporated herein by reference or use other similar systems for prucing a vibration.
[0031] FIG. 2 shows an enlarged version of the avalanche prone region 20 between the lines 14 a and 14 b of FIG. 1 . A plurality of vibration sources 30 are indicated by the reference numerals 30 a through 30 j . Surrounding one of the vibration sources 30 a are a plurality of vibration sensors 40 a, 40 b, 40 c and 40 d . Each of these vibration sensors is an instrument which measures the movement of the ground nearby the sensor and may be an accelerometer or a seismic sensor of the type used to detect, measure and locate earthquakes. Such accelerometers or seismic detectors are commercially available devices which are readily available and provide a time-varying electric signal representative of the displacement (or vibration) of the earth in the area. Also shown in this view (and more fully described later in connection with FIGS. 7-8 ) are components of mast mounting electrical components including a base 152 and an upright member 154 . A separate mast with its electrical components may be provided for each vibration assembly, or, if the vibration assemblies are close together, a single mast with common electrical components may be provided to serve (provide electrical power for) multiple vibration devices. In this case, the base 152 and upright member 154 (along with their electrical components, not explicitly shown) are located among four different vibration devices, 30 a, 30 b, 30 c and 30 d, and the single arrangement of electrical components and mounting structure provides the electrical power for these vibration devices, connected by wiring not shown and provided with any distribution connections which might be desirable.
[0032] FIG. 3 shows a view of one vibration-inducing assembly which is useful in practicing the present invention. A drive assembly 100 from a golf cart has been removed from that environment and mounted to a mass member 200 such as a concrete culvert which is large enough to accommodate the drive assembly. The drive assembly 100 includes a pair of drive wheels 110 coupled through an axle 120 to a motor 130 . The motor 130 in such a system may be a direct current motor operating at 24 volts, and one such golf cart might include four (4) twelve volt direct current batteries. The wheels 110 are typically mounted with weights to balance the wheels to avoid vibration, but in this case, vibration is desired, so if the wheels 110 do not already have an inherent vibration (or if the vibration is not at the desired frequency or intensity), then additional weights are added to the wheels to provide additional vibration when the wheels are rotated.
[0033] Using components from a golf cart or similar device also allows for the use of control mechanism (a throttle assembly, not shown) to be used to tune the device by selecting a desirable frequency at which to operate the vibration device. Such a tuning of the vibration system may be accomplished as taught in the Tuning Patent referenced above.
[0034] FIG. 4 is a side view of the drive system 100 useful in the present invention (without mounting into the mass such as a concrete culvert). The drive system 100 includes the wheels 110 , the axle 120 and the motor 130 as well as conventional mounting hardware. The wheels may be filled with epoxy to reduce the maintenance issues (air has a tendency to leak out of some tires, and these assemblies may be mounted in locations which are difficult to service, so it would not be convenient to have air-filled tires checked periodically to make sure that the tires are inflated to the desired air pressure. Alternatively, solid rubber tires could be used to advantage in the present design, if desired, to avoid the necessity to refill the tires with pressured air periodically or to check the pressure of the air in the tires.
[0035] FIG. 5 is an end view of one of the wheels 110 (looking in the direction of the arrows from the line V-V in FIG. 4 ), showing the addition of additional weights 112 to provide imbalance and allow the wheels and the drive assembly 100 to vibrate as the wheels 110 are turned by the motor 130 . The additional weights are mounted in an asymetric arrangement to provide the desired amplitude and frequency of vibration, vibration which may be measured and tuned as described in the Tuning Patent referenced above.
[0036] FIG. 6 is another view of the drive assembly of FIGS. 4-5 , showing the wheels 110 , the axle 120 and the motor 130 along with mounting hardware.
[0037] FIGS. 7 and 8 show a mounting mast suitable for use in the present invention. The mast 150 includes a base 152 and an upright member 154 with solar or photoelectric cells 156 for generating electric power when the sun is shining. A plurality of batteries 158 are also mounted in a battery box 159 to the upright member 154 . In this way the solar cells and the batteries are mounted up from the ground and away from some of the snow and other moisture which might be on the ground.
[0038] FIG. 9 shows a flow chart for the steps of the method involved with the preferred embodiment of the present invention. In a first step 210 , a drive system is removed from a transportation device, such as a golf cart (other transportation products, such as automobiles or trucks, could also be used, but have the disadvantage of being larger and heavier). That is, a motor and driven wheels are removed from the transportation device. The second step 220 involves modifying the drive system to increase the vibration of the wheels when rotated about the axle, for example, by mounting weights on the wheels in an asymmetric arrangement. It will be appreciated that a normal mounting for the wheels on a transportation vehicle attempts to make the wheels as symmetric as possible by mounting weights by “balancing” the tires to the extent possible. In this case, however, it is desirable to have the wheels substantially out of balance to create substantial vibration as the wheels turn and that can be accomplished by mounting weights in an asymmetric fashion around the periphery of the wheels to increase any vibration from being out of balance. Then, at step 230 , the drive assembly is mounted to a member of significant mass, such as a concrete culvert which is larger than the drive system being used. That significant-mass member is then advantageously secured to the ground, as by forming at step 240 an aperture in the ground somewhat larger than the outside cross-section of the member of great mass and inserting the mass member and drive system within the aperture at step 250 . If desired, then the member of great mass may then be secured within the aperature in a suitable manner, such as by using cement or concrete, to provide a better connection between the member of great mass and the ground, allowing for improved transmission of the vibration from the asymmetric wheels through the mass member and the ground. The source of vibration then ay be tuned as described in the Tuning Patent referenced above, or other suitable means may be used to select an operating frequency for the drive assembly. The mast and power supply are mounted, preferably away from the opening, at step 260 and power from the power supply are used at the desired time at step 270 to energize the drive system to provide a vibration to trigger a controlled avalanche.
[0039] As will be appreciated by those handling systems which impart a significant vibration, the mounting of some of the electrical components on a vibrating member may decrease the useful life of selected electrical components as well as reduce the effectiveness of the assembly. For example, mounting of batteries to a significantly-vibrating member should be avoided, if possible. Also, since the solar panels are oriented toward the sun to produce the greatest power, vibrating those panels can reduce their effectiveness, since those panels will be moved away from the desired position as the panel is vibrated. Thus, it is desirable to mount the battery and the solar panels separate from the vibrating mass to reduce the effect of the vibration and to allow for greater efficiency.
[0040] Of course, many modifications are possible to the present invention without departing from its spirit and some of the features described can be used to advantage without the corresponding use of other features. For example, the drive system from a golf cart might easily be replaced with a drive system from another similar device, including as a land vehicle such as a car or truck or tractor. Further, those skilled in the relevant art will appreciate that the present invention can be operable without being at its greatest effectiveness. Various devices to provide the desirable mass can also be substituted for the concrete culvert described herein. Further, various other shapes of masses, either single pieces or assemblies of multiple pieces, can be used other than cylindrical mass of a concrete culvert, especially if the ground has a complementary recess to receive the mass. The devices and methods of the preferred embodiment which has been described in some detail in the foregoing material may also include things which are desirable, but not essential, to the practicing of the present invention. For example, tuning of operating frequency of the present invention as described in the Tuning Patent may be desirable in many situations, but is not believed to be essential to practicing the present invention, especially if the soil in the area is known and similar devices have been operated in such soil. It is also suggested that the system be re-tuned at periodic intervals, such as annually, to compensate for changes in the soil and/or attachment or changes in the operating characteristics of the vibrational source. It may also be possible to predict the changes over time or in connection with different soils and adjust for the suspected changes in the operational characteristics without redoing the testing. Various other techniques to tune the vibration system may be employed, such as using the tuning information from historical records or similar devices in other locations, if desired, or tuning may be determined to be unnecessary in some situations. Accordingly, it will be appreciated that the description of the preferred embodiment is for the purpose of illustrating the principles of the present invention and not in limitation thereof.
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A method and system for inducing a planned or controlled avalanche is disclosed. The system includes one or more sources of vibration mounted within a mass which is mounted within an aperture in the ground in the area where an avalanche has been determined to be likely to occur. The source of vibration is a drive system from a vehicle (such as a golf cart), preferably modified to increase the vibration and mounted in a vibrating mass (such as a concrete culvert). The vibrating mass may be mounted within an aperture in the ground and secured in place using concrete to increase the vibration-transmitting characteristics of the vibrating mass. An electrical system including a source of electricity and a storage device, as well as controls, is mounted separate from the source of vibration and the vibrating mass (e.g., the concrete culvert) to isolate portions of the electrical system (including the storage device) from some of the effects of the vibration.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation of U.S. patent application Ser. No. 10/372,624 filed Feb. 24, 2003, which is a continuation of U.S. patent application Ser. No. 09/292,024 filed Apr. 16, 1999, entitled METHOD FOR REDUCING CONGESTION IN PACKET-SWITCHED NETWORKS.
FIELD OF THE INVENTION
[0002] The present invention relates to communication networks and, more particularly, to methods and systems for reducing congestion in a packet-switched or hybrid network.
BACKGROUND OF THE INVENTION
[0003] With the explosive growth of today's information superhighway have come the inevitable traffic jams. Congestion is a serious problem today on the Internet, a worldwide system of computer networks using packet-switching technology to transfer messages between computers. Packet-switching protocols such as the Transmission Control Protocol/Internet Protocol (TCP/IP) divide messages into packets which travel along a path in the network that can be varied as conditions in the network change. Specifically, TCP/IP, as currently implemented in the Internet, routes packets independently of each other, utilizing its best efforts without any specific concept of a “connection”. Accordingly, in the Internet, there is little notion of “quality of service”, no notion of guaranteed throughput, and no notion of bounded transmission delay.
[0004] Current implementation of TCP/IP rely on packet loss as a indicator of congestion in the network. As the network experiences congestion, data flowing through a network router becomes bottlenecked in a queue until the queue overflows and packets are lost. Load reduction is accomplished by utilizing a well-known “congestion avoidance” algorithm first described by Van Jacobson in 1988. See “Congestion Avoidance and Control,” V. Jacobson, ACM SIGCOMM-88, August 1988, p. 314-29; “TCP Start, Congestion Avoidance, Fast Retransmit, and Fast Recovery Algorithms”, W. Stevens, RFC 2581 (revision of RFC 2001), which is incorporated by reference herein. In what is coined a “slow start”, a TCP source begins inserting packets into the network by starting with a minimal congestion window, allowing at most one unacknowledged packet in the network. Each time an acknowledgement (ACK) is received, the congestion window is enlarged exponentially until a first threshold is reached or until a packet is dropped. If the first threshold is reached, the TCP source continues to enlarge the congestion window linearly until either a second threshold is reached—or until a packet is dropped. Upon the timeout of a retransmit timer (thereby indicating a dropped packet), the TCP source reduces the transmission rate and “backs off” to its minimal window, with the goal of allowing the network to reach some form of equilibrium.
[0005] As traffic on the Internet increases and more applications are run which are sensitive to the delay caused by dropped packets (e.g., streaming audio and video), proposals have emerged to add some form of explicit congestion notification (ECN) to TCP. See “TCP and Explicit Congestion Notification”, ACM Computer Communication Review, V. 24 N. 5, Oct. 1994, p. 10-23; “A Proposal to add Explicit Congestion Notification (ECN) to IP”, K.K. Ramakrishnan and Sally Floyd, RFC 2481, which is incorporated by reference herein. For example, a network router with a queue nearing an overflow, rather than merely waiting for a packet to drop, can transmit a signal (in the form of a special bet in the packet's header) to indicate the presence of network congestion. The receiver's acknowledgement packet passes the notification on to the sender, which in turn slows down its transmission rate.
[0006] These methods of controlling congestion by signaling for a reduction in transmission rate, however, do not address the root problem—namely, insufficient transmission capacity to support the explosive growth in the number of users demanding access to the Internet at the same time. Short of increasing the capacity of the network, these methods of addressing congestion can make performance degradation more gradual, but they cannot prevent it altogether. It would be preferable to establish a system that reduced congestion in the network by affecting the network usage habits of the people accessing the Internet, and thereby directly addressing the problem of overrunning the capacity of the network.
SUMMARY OF THE INVENTION
[0007] The present invention permits a network service provider to detect an operational condition—such as congestion—in a packet-switched network and to alleviate such congestion by providing customer incentives to avoid use of the network. The detection mechanism triggers an incentive such as the modification of the user's access charges and the customer can be immediately notified of either the occurrence of the congestion or of information regarding the incentive. Usage of the network during congested periods can be deterred by imposing additional access charges during such periods—similarly, customers can be given a discount to encourage usage during periods of low congestion. An incentive schedule can be tailored to dynamically change the usage patterns of the customers of the network to accommodate the operational conditions in the network. The present invention has application in the Internet, where a detection/notification mechanism, for example, can be implemented in a network node such as a router or in a network endpoint such as a client machine or a proxy or mail server.
[0008] These and other advantages of the invention will be apparent to those of ordinary skill in the art by reference to the following detailed description and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a block diagram of a packet-switched network illustrating an embodiment of the present invention.
[0010] FIG. 2 is a diagram showing the movement of illustrative packets in a packet-switched network between a sender and a receiver as a function of time.
[0011] FIG. 3 is a block diagram of a packet-switched network and a proxy server illustrating another embodiment of the present invention.
[0012] FIG. 4 is a block diagram of a packet-switched network illustrating another embodiment of the present invention.
[0013] FIG. 5 is a diagram of a user display with a popup window in the upper right hand corner of the display showing information regarding congestion in a packet-switched network.
DETAILED DESCRIPTION
[0014] The present invention is illustrated with reference to FIG. 1 which shows a packet-switched network 100 having numerous packet-switching nodes 110 to 119 connecting endpoints 101 and 102 . Endpoint 101 and nodes 110 to 115 are assumed to be under the control or supervision of a network service provider; the remainder of the network is assumed to be controlled or maintained by other providers or entities. The network service provider provides access for users to the network for an access charge. For example, where the network 100 is the Internet, an Internet Service Provider (“ISP”)( such as AT&T WorldNet™ provides access to the Internet for its customers. In the case of the Internet, 110 to 115 represents routers and endpoints, 101 and 102 can be client machines, servers, proxy servers, mail servers, news servers, etc. FIG. 1 , of course, is a simplification as a typical communication network would encompass other network elements that would be apparent to one of ordinary skill in the art. Furthermore, although the discussion below focuses on service providers, one of ordinary skill would easily recognize that the present invention applies equally to other network entities such as, for example, corporate networks that utilize charge-back schemes.
[0015] In accordance with the present invention, operational conditions such as congestion in the network are detected in a network nodes 110 to 115 and/or at an endpoint 101 in the network under the control of the network service provider. Upon the detection of the condition, whether at a router or an endpoint, the present invention generates incentive information, such as billing records reflecting a reduction or an increase in the access charge paid by a particular user. This information can be relayed to a billing server or some other billing apparatus for processing. A notification mechanism permits the user to receive notice of the incentive, either by notifying the user of the presence of the operational condition (e.g., congestion) or of the incentive information (e.g. the modified access charge).
[0016] The specific detection mechanism will depend on the particular operational condition in the network sought to be detected as well as the protocols that can be used in the network to signal the condition. For example, each node 110 - 115 is customarily equipped in a packet-switched network with a large number of buffers for storing packets in anticipation of routing or awaiting availability of an output link. With regard to packet congestion, such symptoms develop first in the node's buffers or queues, as the buffers become filled and unavailable to store incoming packets. Thus, a router knows that the Internet is getting congested because its buffer queue for some output link is too long or is getting too long. Some routers today utilize a mechanism called Random Early Detection (“RED”) which signals the presence of congestion as it develops by dropping packets when the average queue length exceeds some threshold—rather than waiting for the queue to actually overflow. See RFC 2309, which is incorporated by reference herein.
[0017] Where endpoint 101 is a sender of packets across the network, see FIG. 2 , it will also be aware of the congestion developing in the router's buffers. Endpoint 101 , using TCP/IP, expects to receive an ACK 202 after transmitting a packet 201 through the network. Failure to receive an ACK signifies that the packet has been dropped by some router between it and the destination endpoint 102 . Where, however, endpoint 101 is a receiver of packets (and endpoint 102 is, accordingly, the sender), the situation is a bit more subtle. The TCP process layer at endpoint 101 , as it receives the packets 201 , 203 , etc. sent by 102 , knows the order in which to reassemble the packets based on a sequence number in the received packets— headers. Endpoint 101 , thus, expects to receive the packets in a certain order and can infer the dropping of a packet by looking for “holes” in the packets— sequence numbers. An out-of-sequence packet, especially if there is a significant delay before the hole is filled, in general indicates that the expected packet has been dropped due to congestion. This method does not guarantee absolute detection of every dropped packet since, for example, packet loss will be invisible to the receiver if the trailing packet/packets in a sequence are dropped. Nevertheless, the method statistically provides good detection of dropped packets, especially for long transmissions (which is the situation a network service provider would be the most concerned about). Alternatively, the endpoint could use duplicate packets as an indicator, although the method would not be expected to be as good as a method based on detecting a hole and a timeout.
[0018] The situation is simplified if the network has ECN capabilities. In that case, where the router experiences congestion in its buffers (whether by a buffer overflow or by RED), it sets a “Congestion Experiences” (“CE”) bit in the packet header of packets from ECN-capable transport protocols. See RFC 2481. The receiver of the packet detects the CE bit and sets a “ECN-Echo” flag in the header of a subsequent ACK packet sent back to the sender. Endpoints 101 and 102 are thus quickly notified of the congestion condition in a router and can react accordingly.
[0019] The above detection mechanisms have been described with respect to the Internet protocol suite although, as noted above, the present invention works with applications and protocols other than reliable data transfer over TCP (as well as non-TCP/IP networks such as Ethernet, hybrid networks, etc.). For example, the instant methods of congestion-based incentives work with multicast communication as well as unicast communication. Consider a multicast audio application that runs over RTP/UDP (the Real Time Protocol over the User Datagram Protocol). In multicast audio, a sender transmits a stream of packets containing audio samples to multiple receivers. These applications do not require that every audio sample be reliably delivered, but they do require some reliability in order to maintain acceptable audio quality. RTP in particular uses sequence numbers to order packets and detect losses at each receiver. A lost RTP packet signals congestion just as a lost TCP packet does. RTP packets can also arrive at a receiver, in principle, containing an ECN (Explicit Congestion Notification) signal placed there by the network. Furthermore, RTP receivers send periodic reports back to RTP senders. Senders use these reports to monitor communication quality and possibly adapt their behavior when there are problems. RTP reports can also carry ECN-Echo signals back to the send. Therefore, both implicit and explicit congestion signals can be used in the context of the present invention as already described above.
[0020] To see how the present invention can be implemented in a real-world setting such as the Internet, it is necessary to understand the typical operating environment. About 70 to 75% of the traffic in the Internet today utilizes the Hypertext Transfer Protocol (HTTP), i.e., Web page retrieval. Furthermore, most congestion in the case of HTTP will occur on user-bound packets, since that is the direction of most Web traffic. Some users connect directly to the Web server of interest; others go through what are known as proxy servers. Often operated by network service providers, a proxy server acts as an intermediary between a user terminal and the Internet to provide caching services. By caching frequently-requested pages, a proxy server can reduce the bandwidth necessary for the provider's own connection to the outside world. The present invention, then, should handle the case of both direct and proxy connections to the outside world, especially (but not exclusively) for Web traffic.
[0021] First, consider the case of a user of a proxy server. With reference to FIG. 3 , proxy server 301 receives a request from the user 300 for an Internet service (e.g. a Web page request from server 302 ) which the proxy server forwards through the Internet 305 using its own IP address—assuming the request passes filtering requirements and cannot be satisfied by the internal cache. When the proxy server receives the requested page, it relates it to the original request and forwards it back to the relevant user. A proxy server, as a receiver of packets from outside Web servers, can use the present invention to detect congestion in the network and attribute it to the customer who requested the specific Web page. It is also a sender on the provider's own network; this, too, can be noted appropriately. The proxy server is thus perfectly positioned to detect and charge for requests over congested networks. The same analysis holds for operator-provided e-mail and, to a certain extent, news servers maintained by the operator. When sending or receiving mail on behalf of a given customer, operational conditions internal and external to the network can be detected, noted, and billed accordingly. (It should be noted, however, that there could be philosophical problems with regard to the application of the present invention to the receipt of unsolicited mail during periods of congestion; see the discussion below on service-level congestion.)
[0022] Suppose, though, that the user does not utilize a proxy server and is connecting directly to the Internet, whether for Web-browsing or something else. See FIG. 4 . In this case, the end systems that detect the congestion most easily are the customer's machine 401 and some endpoint 402 not under control of the network operator. While the former is ideally placed to notify the user, it clearly cannot be trusted to generate charge records for purposes of billing. Under certain circumstances, it may be possible to gather data reliably, such as when the customer utilizes a tamper-resistant modem supplied by the network operator. Otherwise, the routes 410 to 415 in FIG. 4 operated by the network service provider should be used to detect congestion and gather the data necessary to generate the appropriate billing records.
[0023] The only case not covered, then, is when congestion occurs, but on a router not under the control of the local network operator, i.e. routers 416 to 419 . Arguably, this is not a matter of local concern, since the local network operator is not paying for the bandwidth. There is a situation of interest, however—namely, when the router detecting the congestion is at the other side of a comparatively slow link between the local network operator and an upstream service provider. There are two possible ways to overcome the problem: First, the local operator can provide the routers for both ends of the slow link. At the upstream end, a fast link can connect to the local provider's router; this, then, reduces to the previous case. Alternatively, by contractual arrangement the upstream provider can detect and record congestion on behalf of the local operator. This situation can be generalized. Network service providers can detect congestion attributable to other customers of other network operators, and notify and bill them appropriately. A special-purpose “congestion indication protocol” can be utilized to pass the information between network operators. Accordingly, all users of an upstream provider can be charged for the congestion that they cause, rather than trying to attribute the problem to individual users.
[0024] Clearly, notifying the users of the incentive is important: if users do not realize there is a problem in the network (and a surcharge/reward), they will not modify their behavior at appropriate times. Direct notification from the network provider is straightforward where the present invention is implemented as a user process running on a direct endpoint capable of detecting congestion. With other configurations, other mechanisms for notifying the customer can be utilized. For example, when the user is in contact with only some local server, service-specific mechanisms can be utilized. When the customer is accessing Web pages through a proxy, a Java or Javascript applet can be sent to the user in the first Web page retrieved which, in turn, displays to the user the relevant notifications regarding congestion and incentive information such as the effect on access charges. Similarly, the mail retrieval protocol could be modified to send appropriate information to the customer when accessing a mail server to check the user's e-mail (or create a new e-mail).
[0025] The notification can be in the form of a window or screen “popup” on the user's display. A small window could be displayed on the user terminal indicating the level of congestion in the network in some visually intuitive and appealing form such as a speedometer. See FIG. 5 . Moreover, other forms of notification can come from pre-emptive detection mechanisms. In common assigned U.S. Pat. No. 5,870,557, “Method for Determining and Reporting a Level of Network Activity on a Communications Network Using a Routing Analyzer”, the disclosure of which is incorporated by reference herein, a method is disclosed for periodically analyzing the congestion along routes from an access provider's entry point to the Internet to a set of desired Web sites. Round trip times and packet loss information collected from use of the “traceroute” command are utilized to identify congested links. The transmit characteristics are compiled and analyzed to provide a user with useful information about congestion along routes to the Web sites of interest and in order to warn users to avoid traffic to some Web sites at congested periods of time. Such preemptive mechanisms can be utilized with the present invention to provide a customer with prior information on the operational condition of the network before incurring any charges for usage of a congested link. Accordingly, a customer can be prompted before deciding to access the network in a manner that will generate any incentive information such as a modification to a customer billing record.
[0026] Moreover, it should be apparent from the above example that the notification mechanism need not be coupled to the network's detection and incentive mechanisms. Self-notification mechanisms can be utilized by the user. As long as users have received some notice of the general contours of the incentive, perhaps at registration, they can utilize whatever local detection/notification application scheme on their own computer terminal they choose to, such as the preemptive reporting application described above. The network service provider need only concern itself with detecting congestion and detecting usage.
[0027] The present invention has been described with respect to the operational condition of the network itself. Rather than focusing on a condition such as network congestion, the idea can be generalized to encompass “service” or “application-level” congestion, i.e. congestion as an attribute of a service or application as opposed to a network. The incentive information can be generated as a function of some condition of a service/application provided by the network operator to the customer.
[0028] For example, it is known that the load on e-mail servers increases near Christmas time, as users send each other holiday greetings laden with graphics and audio. See “Graphic-Laden Holiday Greetings Clog Servers at AT&T WorldNet”, Wall Street Journal, Dec. 10, 1998. As the added multimedia makes the messages much larger than regular text e-mail, the mail servers become overloaded resulting in significant slowdowns in the delivery of incoming and outgoing mail. The present invention can be utilized to detect the increasing load on the mail server and to notify and charge customers submitting large messages during such periods of service congestion. Similarly, receiving and storing certain high-volume newsgroups can be a considerable burden on a network operator trying to maintain a news server for its customers. Users who access such newsgroups by reading or posting to them could be notified and billed accordingly.
[0029] Service congestion detection can be accomplished by modifying the mail protocol or the netnews protocol. Where a change in the protocol is undesirable, fake congestion indicators can be generated. While artificially dropping packets in order to signal service-level congestion would be counterproductive, an ECN congestion bit can be set to notify the user of the service-level congestion. This scheme will work for any application where most of the data is sent from the server to the user, since it will then have a minimal effect on actual transmission speeds.
[0030] Although the embodiments of the present invention are described with respect to the Internet, it would be easily recognized by one of ordinary skill in the art that the present invention is applicable to packet-switched networks in general. The foregoing Detailed Description is to be understood as being in every respect illustrative and exemplary, but not restrictive, and the scope of the invention disclosed herein is not to be determined from the Detailed Description, but rather from the claims as interpreted according to the full breadth permitted by the patent laws. It is to be understood that the embodiments shown and described herein are only illustrative of the principles of the present invention and that various modifications may be implemented by those skilled in the art without departing from the scope and spirit of the invention.
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The present invention permits a network service provider to detect an operational condition—such as congestion—in a packet-switched network and to alleviate such congestion by providing customer incentives to avoid use of the network. The detection mechanism triggers an incentive such as the modification of the user's access charges and the customer can be immediately notified of either the occurrence of the congestion or of information regarding the incentive. Usage of the network during congested periods can be deterred by imposing additional access charges during such periods—similarly, customers can be given a discount to encourage usage during period of low congestion. An incentive schedule can be tailored to dynamically change the usage patterns of the customers of the network to accommodate the operational conditions in the network. The present invention has application in the Internet, where a detection/notification mechanism, for example, can be implemented in a network node such as a router or in a network endpoint such as a client machine or a proxy or mail server.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to industrial water cooling towers and particularly to towers of that class which are fire resistant. Novel passive vent means is provided for venting the interior of the tower when a fire occurs to enhance suppression of the combustion process.
2. Description of the Prior Art
Industrial sized water cooling towers have found extensive use in large industrial, business and multiple resident complexes because of their ability to efficiently dissipate large amounts of process or occupancy generated heat to the atmosphere. Cooling towers of this type are found in various areas including factory complexes, chemical processing plants such as petrochemical facilities, near offices, at hospitals, as a part of multi-family apartments or condominiums, as a part of large commercial retail properties, warehouses and electrical generating stations including nuclear power plants.
Cooling towers are constructed of any one of a number of materials including wood, fiberglass, concrete or steel structure, with plastic, wood or ceramic type fill materials. In many instances, uninterrupted operation of the tower is a critical factor because of the importance of continuity of the cooling system to overall process operation, and the particular function of the dependent operating system. The primary job of a cooling tower is generally the efficient cooling of water for processes or facilities. As a result, other design considerations are generally subordinate to the primary cooling function.
However, one usually subordinate design element that can become paramount under certain circumstances relates to fire safety. This is especially true if a tower fire has the potential of endangering personnel in a high occupancy area near the tower, or shut down of the tower because of a fire would adversely affect a process, a production facility or a utility such as a nuclear power plant. Because of these potential hazards, users, insurance carriers, contractors and fire authorities may mandate that the cooling tower be constructed of low combustion materials and of a fire retardant design, or otherwise protected against fire hazards with fire suppression systems such as water sprinklers.
The initial approach to low combustibility tower design was to use non-combustible structure and frame materials combined with a low efficiency, high cost, heavy brick or ceramic type fill, or no fill at all. However, the cost per unit of cooling of these designs was substantial and in most instances not an economically viable option. Later designs retained the non-combustible structures and frame materials previously used, but combined them with lighter weight and less expensive fire retardant fill material having low flame spread characteristics. Low combustibility materials alone however, did not guarantee fire safety.
Configuration and tower design details are critical to actual fire performance of a given model of a tower. Fill materials, although constructed of fire retardant materials, were usually not supported in configurations that substantially limited burning. More fire resistant fill configurations had to be created giving the overall design greater protection from fire damage and shut down. However, concrete and steel support structures were the only acceptable materials for use with the fire retardant fill configurations.
Tower designs which are the most economical and efficient generally have poor fire resistance. This is true of towers having wood frames and plastic fill. Douglas fir for example is an excellent construction material for most industrial cooling tower applications, providing longevity at a very economical price. Towers constructed of fir though are flammable and can completely burn down when exposed to a fire condition and the tower is not in operation. In certain circumstances, inability of the tower to meet fire protection specifications may rule the tower out for a particular application, or require installation of a fire protection sprinkler system which is not only expensive to install but also to maintain under varying ambient conditions. A secondary overall concern with wood towers is the environmental problems associated with leaching of preservative treatment chemicals. Preservatives are necessary to increase the longevity of the wooden cooling tower components under wet conditions.
Fire resistant towers are usually constructed of materials which are not self-propagating from a combustion standpoint. Conventional fire resistant components includes the structural components of the tower such as the upright support members, girts and the like, the fill assembly, the water distribution means overlying the fill assembly, and the casing and fan deck forming an enclosure for the tower.
Each material of construction has certain advantages and disadvantages. Among the factors involved are overall cost, combustibility of the particular material, corrosion resistance, and long term durability effecting longevity of the tower or suitability of the construction materials to a given end use. The ultimate goal would be to provide a cooling tower design which utilizes the highest efficiency components available, with the longest lasting materials of construction, and which cooperate to provide a required cooling function. Protection from material breakdown and strength loss as a result of metal corrosion or wood rot while offering protection from an external risk such as fire has been a long sought but not fully attainable goal. This has been particularly true from a cost benefit standpoint.
Cooling towers which are essentially unprotected from fire hazards, primarily those fabricated from wood, burn rapidly and completely when exposed to risk. Cooling tower fires in some instances may be impossible to extinguish via external fire fighting techniques and therefore require fire detection capable of detecting a combustion event and immediately initiating operation of a fire suppression system.
Fire suppression Systems such as sprinklers have been found to be generally reliable and serve well in several studies of fire incidents involving cooling towers. However, in order to be completely effective, more than one level of sprinklers are usually required on very tall tower configurations. However, sprinkler systems are very maintenance dependent insofar as corrosion is concerned and offer particularly difficult design considerations insofar assurance of water supply under freezing conditions.
Not only must the system provide rapid fire detection with low probability of false signaling, necessitating complex and costly detectors such as thermistors or the like. In addition, the water release mechanism must be positive and instantaneously responsive to fire detection. Sprinkler heads having melt out plugs have been employed, but squib actuated deluge valves are preferred because of their faster reaction time. Although these systems have proven to be effective as installed, they are expensive and extremely difficult to maintain on a regular basis over intervals of time that normally involves many years where there is no functional need for the system to operate.
Because sprinkler systems are expensive to install and require many specific care actions and programed maintenance, cooling tower users have sought to eliminate the need for such systems based on tower designs. These alternative design concepts have for the most part relied upon the use of non-combustible materials which are much more expensive than wood. Furthermore, the designs must meet customer acceptance standards and desirably comply with industry standards such as those receiving Factory Mutual (FM) approval, without the use of sprinkler protection. This entails not only structural protection in fires, but also limited combustion spread, especially laterally in the fill assembly, which represents the area of highest internal BTU content.
FM approval has typically been based on testing of tower mock ups for full tower sections for fire resistance. The FM approval process is based on placement of a very substantial ignitor in the lower part of the tower, and then observation of the effect of that ignition on the test cell or tower as a whole. A one foot by one foot plan area pan containing heptane to a depth of three inches is placed in the tower below the fill assembly and ignited. FM has not published specific judgment criteria, but instead issues approvals case by case based on test observations.
With the advent of synthetic resin framing components for cooling towers, as for example polyester resin reinforced with fiberglass, usually referred to as FRP or GRP, the provision of a fire resistant cooling tower which has required strength, durability and longevity characteristics, has become closer to reality. The use of FRP in the construction of cooling towers has slowly evolved over the years. Glass fiber reinforced synthetic resin components such as fan stacks, fan blades, fill support grids and wood tower braced diagonal connectors have been used for a number of years and have established FRP as a durable material in the corrosive cooling tower environment. In more recent years, virtually the entire components of a cooling tower have utilized FRP materials to provide effective corrosion resistance while retaining required structural strength. Exemplary is the "Four-way Crossflow Water Cooling Tower" of U.S. Pat. No. 4,788,013. Towers of the type disclosed in the '013 patent using alternative materials have become closer in cost to prior wood designs, particularly when the properties of cooling efficiency, superior corrosion resistance, long term longevity and overall maintenance and replacement costs are taken into account.
FRP cooling tower design interests have now focused on producing a low combustibility, low fire risk design in pultruded fiberglass structural material using high efficiency low flame spread fill materials such as polyvinyl chloride (PVC).
The assignee hereof has obtained a number of FM approvals on crossflow and counterflow cooling towers. These designs have been characterized by steel or concrete framing and PVC fill and eliminators in various configurations. Also approved have been fiberglass reinforced polyester fan blades, fan cylinders and distribution pipes along with PVC distribution piping and polypropylene type adaptors and nozzles. Approved tower sizes have ranged from relatively small towers, 4 feet by 4 feet by 6 feet to very large towers having a diameter as much as 400 hundred feet and a concrete shell 500 feet tall.
An FM approved tower incorporating a non-combustible ceramic tile fill is very inefficient in cooling capacity, is size limited based on fill weight, and is a very expensive design. A more recently approved tower design employs an extra cell for redundancy and an impenetrable fire barrier between each cell. The extra cell is required because a whole tower segment between any barrier location is subject to total fire exposure. Manifestly, provision of an extra cell protected by a fire barrier is a very expensive and therefore undesirable attempt to solve the fire hazard problem. PVC fill in a combustible support frame requires a substantial fire barrier and significant extra tower capacity. Burning cannot be controlled by design in any current FRP framed, PVC filled tower design.
A number of fire hazards exist in connection with cooling tower installations. The primary fire risks are associated with: 1) electrical equipment malfunctions and shorts, principally occurring in fan motors or junction boxes; 2) lightning strikes; 3) welding/cutting torch sparks from on or near the cooling tower; 4) sparks from an external source in the area such as an incinerator; and 5) careless storage of combustibles on, near or under the cooling tower, creating ignition sensitivity problems. Contrary to what would be expected, studies have shown that at least a third of cooling tower fires occur while the tower is in operation. The principle fire risk areas are the fan deck which is exposed to external sparks, and the fill assembly, because of its combustible nature and large BTU content in a limited internal area.
As a consequence, principle efforts to limit fire risks have heretofore for the most part been directed toward use of non-combustible materials, especially the fill components, and structural members, by configuration alternatives to limit fill combustion, by adding well maintained sprinkler systems with adequate water supply that is not subject to freeze up or corrosion, by adding lightning protection, by careful siting to avoid high risk locations, by specific management control of cutting and welding activities because of the high number of fires which result from these sorts of accidents, and by initiating emergency reaction readiness planning.
SUMMARY OF THE INVENTION
Although a cooling tower may be constructed of fire resistant materials, once a major fire has started within the tower, the fire resistant materials in effect may become combustible because of the rapid build up of heat that occurs within the interior of the tower. Towers in accordance with this invention have novel passive, normally closed air vents in the tower casing and/or fan deck which upon opening as a result of sensing of a fire serve to vent the interior of the tower to the atmosphere when a fire occurs inside of the tower thus enhancing suppression of the combustion process.
In the past, as noted, efforts to control fires in cooling towers have been directed to external protection such as sprinklers, or to the use of fire proof or fire retardant materials of construction. It has not been previously recognized that if a cooling tower is vented immediately adjacent the situs of a fire, the rapid release of hot products of combustion adjacent the fire site accompanied by flow of cool air from the surrounding atmosphere across the fire situs will actually function to suppress the fire and minimize lateral spreading. This is contrary to the conventional wisdom that there is a need to limit air access to the fire rather than increase the amount of air available.
In order to accomplish the intended purpose of suppressing the combustion process during a tower fire, the novel vent structure of this invention preferably includes means presenting apertures in the fan deck and/or the part of the upright tower casing where it joins the fan deck, and which are normally closed to prevent flow of air therethrough to preserve the air tight integrity of that part of the tower enclosure. However, the means normally closing the apertures comprises passive components which function to unblock the apertures when flame or the temperature within the tower adjacent thereto increases to a predetermined level thereby allowing air to flow outwardly to the atmosphere rapidly venting the area of the tower immediately above the high heat content fill assembly and serving to suppress a fire within the tower that has spread to the fill and adjacent structural components.
In one preferred embodiment, the normally closed vent structure of this invention comprises a fan deck made up of a series of fire resistant grates presenting a plurality of openings between adjacent grate members, and a layer of synthetic resin sheet material underlying the grates which is characterized by the property of melting or burning at a relatively low temperature so that when a fire occurs in a part of the tower, the hot products of combustion including the flame rising from such fire causes the sheet material immediately thereabove to melt or burn, thereby providing a vent opening for rapid relief of hot products of combustion through the vent opening thus presented.
An especially important aspect of the invention is the fact that the size of the vent provided is variable and directly dependant upon the extent of the fire within the tower. The greater the cross sectional area of the fire and corresponding area of the flame and/or hot products of combustion rising therefrom, the greater the size of the vent opening that is formed in the fan deck overlying the tower fill assembly. Limiting the vent opening to that required to vent hot products of combustion and/or flames assures the most efficient natural draft venting, while at the same time assuring that the vent opening that is formed is of adequate size under all circumstances, substantially regardless of the nature and extent of the fire.
Another important feature of the invention is the fact that by providing a normally closed grate defining vent as described which makes up the entire fan deck of the tower, a vented opening through the grate may take place in closest proximity to the fire, wherever the fire may occur across the plan area of the tower, thereby suppressing the fire and preventing its lateral spread throughout the fill assembly and associated structural members and fill support components.
In lieu of a grate-like vent normally closed by a readily meltable synthetic resin sheet laying against the inner face of the grate, panels may be provided having a series of openings therein which are closed by individual plugs fabricated of readily meltable, burnable or liquefiable synthetic resin material so that when a fire occurs at any point in the tower, the flame and/or hot products of combustion rising from such fire melt or burn the plugs immediately thereabove thus providing a series of vent openings immediately above the fire to assist in suppression of the fire and especially prevent its lateral spread across the plan area of the fill assembly.
Although a preferred embodiment involves a fan deck with normally closed vent structure, a further alternative construction consists of similarly functioning vents in the upright casing wall around the perimeter of the fan deck. A still further alternative arrangement comprises normally closed vent structure as described in the casing wall proximal to the fan deck, and in the fan deck as well.
Spring biased doors held in closed position across respective vent openings in the fan deck or uppermost part of the tower casing may be substituted for the synthetic sheet closed grates previously described. In this instance, temperature sensitive latches retain the doors in closed disposition until such time as the latches respond to flame and/or hot products of combustion thereby allowing respective doors to open under the spring bias thereagainst.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a vented fire resistant induced draft counterflow water cooling tower, with parts thereof being broken away for clarity and illustrating a preferred embodiment of the normally closed vent structure in the fan deck of the tower, and with the fill assembly being suspended from support structure therefore;
FIG. 2 is a side elevational view of a vented fire resistant induced draft counterflow water cooling tower similar to the tower of FIG. 1 but illustrating a fill assembly which is supported by structural members therebelow;
FIG. 3 is a side elevational view of a vented fire resistant induced draft crossflow water cooling tower, with parts thereof being broken away for clarity, and embodying the preferred normally closed vent structure in the fan deck of the tower;
FIG. 4 is an essentially schematic plan view representation of a water cooling tower illustrated in FIGS. 1 and 2, and showing the preferred vented fan deck construction of this invention;
FIG. 5 is a fragmentary, enlarged, essentially schematic cross sectional representation of a preferred normally closed vent structure in the fan deck of a water cooling tower as shown in FIGS. 1 and 2 and comprising a grate-like deck with a relatively low melting temperature synthetic resin sheet underlying the grate and normally closing off the openings therethrough;
FIG. 6 is a schematic view similar to FIG. 5 and showing an alternative embodiment of the vent structure wherein the openings in the grate-like deck are normally closed by a series of relatively low melting temperature synthetic resin strips in place of an underlying synthetic resin sheet;
FIG. 7 is an enlarged cross sectional view of FIG. 6 to better illustrate the details of construction of the vent structure shown in FIG. 6;
FIG. 8 is a fragmentary perspective view of one of the strips shown in FIGS. 6 and 7;
FIG. 9 is a fragmentary, enlarged, essentially schematic cross sectional representation of an alternative embodiment of the vent structure shown in FIG. 5 and embodying a series of grate-like members interrupted by a plurality of panel members defining a part of the fan deck of the tower, and with a relatively low melting temperature synthetic resin sheet being positioned below each of the grate-like members to normally prevent flow of air therethrough;
FIG. 10 is a fragmentary, enlarged, essentially schematic cross sectional representation of an embodiment of the vent structure hereof similar to that of FIG. 5 but in this instance comprising two layers of grate-like members one above the other, with the relatively low melting temperature synthetic resin sheet being interposed between the two layers of grate-like members;
FIG. 11 is a fragmentary, enlarged, essentially schematic cross sectional representation of another embodiment of the vent structure of this invention wherein the deck is made up of a series of panel members each having a plurality of openings therein normally closed by plugs made up of a relatively low melting temperature synthetic resin material;
FIG. 12 is a fragmentary, enlarged, essentially schematic cross sectional plan view of the panel vent construction shown in FIG. 11;
FIG. 13 is a fragmentary, enlarged, essentially schematic cross sectional view taken along the line 13-13 of FIG. 12 and looking in the direction of the arrows;
FIG. 14 is a fragmentary, enlarged, essentially schematic cross sectional representation of a further embodiment of the vent structure of this invention made up of a series of panels presenting the fan deck of a cooling tower, with at least certain of the panels being provided with vent openings therein, each normally closed by a spring biased door held in closed position by a hot products of combustion activated latch;
FIG. 15 is a fragmentary, enlarged, essentially schematic cross sectional representation of another embodiment of the invention wherein openings in the tower casing wall adjacent the fan deck of a cooling tower are closed by synthetic resin panels fabricated of a relatively low melting temperature synthetic resin material, thereby presenting normally closed vents openable by hot products of combustion thereagainst;
FIG. 16 is a fragmentary, enlarged, essentially schematic cross sectional representation which has panels in the upper part of the tower casing adjacent the fan deck also provided with a series of openings therein normally closed by plugs, and essentially conforming to the configuration and construction of the panels and plugs of FIGS. 12 and 13; and
FIG. 17 is a fragmentary, enlarged, essentially schematic cross sectional representation of vent doors in the upper part of the tower casing and which are similar in construction and operation to the vent doors depicted in FIG. 14.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A typical fire resistant vented counterflow water cooling tower embodying the preferred normally closed vent structure of this invention is designated by the numeral 20 in the drawings. The tower 20 includes a conventional concrete cold water basin 22 and a series of structural upright supports 24 and girts 26 which are fabricated of a fire resistant material such as FRP. A series of upper cross girts 26a support a fan deck 28 which embodies the vent structure of this invention. The fan stack 30 above deck 28 is likewise constructed of a fire resistant material, as for example FRP. The fan assembly 32 of tower 20 includes a gearbox 34 mounted centrally of stack 30 and driven by a motor 36 connected to the gearbox 34 by a shaft 38. The fan 40 has a central hub 42 joined to gearbox 34, and a plurality of radially extending fan blades 44 projecting from hub 42. The fan assembly 32 is carried by torque tube assembly 46 at the upper part of tower 20 which are in turn are supported by the main structural supports 24 of the tower. Fan stack 30 and fan blades 44 are preferably constructed of FRP. The hub 42, gearbox 34, shaft 38, motor 36 and torque tube assembly 46 are usually constructed of metal and therefore are fire resistant.
A fill assembly 48 within tower 20 is preferably comprised of a series of upright, side-by-side, interengaging fill packs 50 which make up a plurality of fill racks 52. Each fill pack has a plurality of upright, side-by-side interengaging PVC sheets 54 which are molded to present an undulating serpentine pattern as schematically shown in FIG. 1. Because of the undulating configuration of the serpentine pattern presenting alternating peaks and valleys in the surface of each of the sheets 54, air passages are presented between adjacent fill sheets to allow flow of air thereacross.
Each of the fill racks 52 is supported by at least two upright, horizontally spaced and aligned hangers 56 of stainless steel or the like and which and which are suspended from cross girts 26b. The hangers 56 associated with each pack 50 carry horizontal stainless steel tubes 58 at the lower ends thereof. The tubes 58 extend through the upper part of a corresponding pack 50. Tubes 58 thereby serve to support each of the fill packs 50 in upright disposition adjacent to a corresponding pack 50 and in interengagement therewith.
PVC is a preferred material for construction of the sheets 54 of packs 50 because it is a high efficiency low flame spread synthetic resin material, and has a sufficiently high melting point to substantially resist deformation at the hot water temperatures encountered in the fill of a water cooling tower.
Hot water distribution means 60 overlying fill assembly 48 includes a main manifold pipe 62, and a series of transverse cross distributors 64 joined thereto, which in turn have a plurality of nozzle pipes 66 provided with distributor nozzles 68 on the outermost extremities thereof. The manifold pipes 62 are connected to a main supply pipe through one or more risers either joined directly to pipe 62, or to a common horizontal connector conduit. Manifold pipe 62 is usually fabricated of FRP, while distributor 64 may be of FRP or PVC, and nozzle pipes 66 and nozzles 68 may be constructed of polypropylene.
Eliminators 70 directly overlying hot water distribution means 60 preferably consists of a series of PVC sheets which are also corrugated to present a series of inclined passages that cause the air flowing therethrough to be diverted from its normal upright path to drop droplets of water to be extracted from the hot air stream.
Casing 72 of tower 20 may be fabricated of a number of pultruded glass fiber reinforced polyester panels 74 of the type described in detail in an application for United States Letters Patent, filed by the assignee hereof on Jun. 6, 1995, Ser. No. 470,762, entitled "Multiple Purpose Panel For Cooling Towers", and which is incorporated herein by specific reference thereto. The panels 74 making up casing 72 around the perimeter of the tower terminate in spaced relationship from cold water basin 22 on at least one side of tower 20 thereby presenting an air entrance 76 below fill assembly 48. Stack 30 receiving fan assembly 32 defines a hot air outlet 78 above the fill assembly 48.
As a consequence, during operation of the tower, ambient air drawn into the tower 20 by the fan 40 through the air entrance 76 from the surrounding atmosphere moves upwardly through fill assembly 48 in counterflow relationship to water gravitating downwardly through the fill assembly 48 which has been delivered onto the top of the fill racks 52 from the hot water distribution means 60. Under cold ambient conditions, natural draft cooling takes place without operation of the fan 48. Therefore, water temperature is monitored to determine when and for what period of time fan assembly 38 is actuated.
Viewing FIGS. 4 and 5, it is to be observed that fan deck 28 comprises a grate unit 80 preferably made up of a series of side-by-side grate panels 82 which define the fan deck which surrounds opening 31 at the bottom of fan stack 30. Preferred grate panels 82 are available from the Aligned Fiber Composites Division of Morrison Molded Fiberglass Company, Bristol, Virginia, and sold under the trademark DURADEK gratings. The preferred grate panel 82 is designated DURADEK Series I-6000 1 1/2". This grate panel is fabricated of a fire retardant vinyl ester and has a 60% open area wherein the width of each open space 83 is 0.9 inch and the width of the top flange of each grate member 84 is 0.6 inch. Each grate member 84 is of transversely I-shaped configuration as shown in FIG. 5 with the individual members 84 being joined and held in the predetermined spaced relationship by a series of cross ties 86 also constructed of fire resistant vinyl ester material and positioned on 12 inch centers. The preferred DURADEK grate panels are available in panel widths of from 6 inches to 60 inches and lengths up to 240 inches.
The width of the grate members 84 preferably is from about 1/4 to 3/4 inch, and the spacing between the bars is preferably from about 1/2 to 1 1/2 inches. The thickness of the grate panels preferably is from about 1 inch to about 2 inches.
One or more sheets of synthetic resin sheet material 88 is provided in underlying, full covering relationship to the underside of fan deck 28 made up of grate panels 82. Sheet 88 is of a synthetic resin having a relatively low melt temperature, with polyethylene, polypropylene, nylon and polyvinyl chloride being suitable materials. A preferred sheet 88 is fabricated of 6 mil nylon. An alternative sheet may be polyethylene which may or may not be reinforced with nylon mesh. Without such reinforcement, the polyethylene sheet should be from about 40 to about 100 mils; with nylon mesh reinforcement the polyethylene sheet should be from about 5 to 20 mils. Means, not shown, may be provided for securing the sheet 88 to the underside of grate unit 80 if desired.
In the operation of tower 20, if a fire occurs, the most vulnerable part of the tower is fill assembly 48 because of its high BTU content. In most instances, the fire initially is confined to a part of the tower and to a portion of the fill assembly 48. As the fill sheets 54 of a particular fill pack are consumed by the fire, the flames rising therefrom burn the area of sheet 88 immediately thereabove, or the products of combustion rising from the fire contact and then collect below that area of sheet 88 until the material melts. Because of the relatively low melting point of the sheet material (polyethylene 98° to 115° C., polypropylene 160° to 175° C., nylon-type polyamide 210° to 220° C. and PVC 75° to 105° C.), the part of the sheet 88 exposed to the flame or hot products of combustion from the fire burns or melts the material thereby unblocking the open area of the grate panels thereabove to vent the interior of the tower so that the hot products of combustion may rapidly escape to the surrounding atmosphere.
Of particular note is the fact that the area of the fan deck 28 which vents is variable and directly dependent upon the extent of the fire and the cross sectional area of the flame or hot products of combustion that rise upwardly to the underside of the fan deck. Similarly, the location of the vented area is also directly dependent upon the location of the fire therebelow. Confinement of the venting to that part of the plan area of the tower where the fire has occurred has the added advantage of assuring most efficient natural draft of air past the tower portion subjected to combustion, and provides the most efficient venting.
Although relatively low melting temperature synthetic resin materials as described are preferred for blocking the openings through grate unit 82, it is to be understood that the blocking material may be of characteristics such that it burns when exposed to flames or softens to an extent that when subjected to hot products of combustion from a fire, the gravitational pull or the air pressure thereagainst within the tower casing may displace the synthetic resin material away from the openings normally blocked thereby, thus providing venting of the interior of the tower.
Tests have established that contrary to expectation, venting of the upper part of the tower enclosure when a fire occurs has the effect of more rapidly suppressing the fire, and especially preventing lateral propagation of the combustion, than is the case without such venting. In addition, the use of a fill assembly made up of a series of side-by-side fill packs which are in interengagement but not joined one to the other provides another advantage in increasing the fire resistance of the overall tower 20. Upon occurrence of a fire, which as indicated generally starts in one part of the plan area of the tower, the fill sheets 54 of a particular fill pack are the first that are subjected to the fire and generally are the ones that are first consumed, at least to a certain extent by the flames of the fire. When a fill pack has been consumed by the fire to an extent that it is no longer supported by the hangers 56 and tubes 58, that fill pack 50 falls away from assembly 48 into the underlying cold water basin 20. In this respect therefore, it is preferred that each of the fill packs 50 be made up of individual sheets 54 that extend the full height of the fill assembly 48.
A preferred fill pack 50 fabricated of PVC sheets may for example be 12 inches wide, 24 inches deep and from 24 inches to 72 inches high. The overall fill rack 52 made up of fill packs 50 nominally constitutes a 6 feet by 6 feet bay pack.
The tower 100 illustrated in FIG. 2 is the same as tower 20 except in this instance the fill assembly 148 rests on and is carried by the underlying girts 126a rather than being suspended from hangers 56 as depicted in FIG. 1. Although the individual fill packs 150 may fall away and gravitate into the cold water basin 122 in the same manner as described in respect to tower 20, the girt supports 126a for packs 150 require that the packs 150 be consumed by the fire to a greater extent than is the case with packs 50. For that reason, suspension of the fill assembly packs from hangers as shown in FIG. 1 is preferred over the bottom support construction of FIG. 2.
Venting of the tower 100 provided by grated deck 128 is the same as that described with respect to the vented deck 28. Thus, a sheet 188 of the same type of synthetic resin material as described with respect to sheet 88 is provided in underlying relationship to the grate unit 180.
In the alternate embodiment of the normally closed vent structure for a vented fire resistant cooling tower as shown in FIG. 6, the fan deck 228 is made up of a grate unit 280 identical to grate unit 80. The grate panels 282 of grate unit 280 are also held in spaced side-by-side relationship by a series of cross ties 286. In this instance though, rather than providing an underlying layer of synthetic resin material such as sheet 88, each of the openings 283 between adjacent I-members 284 of grate panels 282 is closed with a strip 290 best illustrated in FIGS. 7 and 8. As is apparent from those latter Figures, the strip 290 has a central body portion 292 integral with depending rebent leg portions 294 which present an enlarged rib 296. The effective transverse width of each of the leg portions 294 is correlated with the transverse thickness of the flanges of grate members 284 so that the ribs snap into place between adjacent members 284 and are frictionally held therebetween (see FIG. 7).
The strips 290 are also preferably fabricated of a relatively low melt temperature synthetic resin material such as the materials described for use in fabrication for sheet 88. Thus, when strips 290 are subject to flames and/or hot products of combustion rising within the interior of the tower above the fill assembly, that portion of each of the strips 290 which is burned or heated to its melting temperature, melts or burns away thus unblocking the openings 283 between adjacent members 284 and providing for venting of the interior of the tower.
The fan deck 328 embodiment of FIG. 9 differs from the preferred fan deck embodiment shown in FIG. 5 in that the grate panels 382, which are identical to the grate panels 82 of grate unit 80, are in horizontally spaced relationship and are separated by respective panels 374 of identical construction to the panels 74 used to fabricate casing 72. A synthetic resin sheet 388 underlies the grate panels 382, and alternatively, if desired, the panels 374 as well. Although the fan deck construction 28 is preferred as indicated, because that venting arrangement provides the maximum amount of venting available for the entire plan area of the tower, the fan deck 328 embodiment of FIG. 9 offers somewhat more positive support for personnel walking across the fan deck of the tower.
The fan deck embodiment 428 shown in FIG. 10 differs from that of the FIG. 5 embodiment by the provision of two grate units 480a and 480b located in superimposed relationship one above the other. The individual grate panels 482 making up units 480a and 480b may be of the same thickness as grate panels 80, or they may be of lesser thickness as indicated in FIG. 10. The synthetic resin sheet 488, constructed of the same material used for construction of sheet 88, is located between grate units 480a and 480b. Venting provided by the deck of FIG. 10 is the same as described with respect to vented deck 28.
In FIG. 11, the fan deck embodiment 528 depicted is made up of a series of side-by-side panels 574 which are identical to the panels 74 of FIG. 1, except in this instance the planer portions 574a, 574b and 574c of each panel 574 is provided with a series of spaced openings 510 (FIGS. 12 and 13) which are normally closed by respective synthetic resin plugs 512. Each of the plugs 512 is fabricated of a low melt temperature synthetic resin of the type described with respect to the material used for fabrication of sheet 88. Plugs 512 preferably have a flat top 514 integral with a circular side wall 516 presenting a circumscribing external groove so that the plugs may be inserted into respective openings 510 where they remain locked in place. Upon initiation of a fire within the interior of a tower protected by a vented deck of the type designated by the numeral 528, plugs 512 subjected to flames and/or hot products of combustion from the fire burn and/or melt thereby unblocking respective openings 510 and allowing venting of the tower in the area where the plugs have melted and liquefied. Although not illustrated, it is to be understood that the plugged panels 574 may alternate with unplugged panels 74 in the same manner as described with respect to fan deck 328 and illustrated in FIG. 9.
The vented fan deck 628 of FIG. 14 is another alternate embodiment of the invention wherein the panels 674 identical to panels 74 of tower 20 are in spaced relationship presenting an elongated opening 610 therebetween. Each of the openings 610 is normally closed by a door 620 pivotal about a respective pivot support 622 and normally biased into the open position thereof illustrated by the dotted lines of FIG. 14 by spring means such as torsion springs 624. A thermally activated latch assembly 626 associated with each door 620 functions to maintain a respective door 620 in the closed position of the same against the bias of spring 624. Flames and/or hot products of combustion contacting latch 626 ultimately cause the link 628 to melt or vaporize thereby releasing the latching engagement of door 620 with the latch assembly 626 and allowing such door to swing upwardly under the spring bias thereon to the open position thereof. The link 628 preferably is of a material such that it will fuse and melt or vaporize at a temperature approximately the same as the melting temperature of the synthetic resin material used to fabricate sheet 88.
The alternate embodiment of the vent structure shown in FIG. 15 provides venting of the casing of the tower adjacent the perimeter of the tower fan deck. Thus, the casing 772 made up of panels 774 which are of the same construction as panels 74, terminates in spaced relationship from the overlying fan deck 728 to present a perimeter opening 750. A synthetic resin sheet 788 which closes opening 750 is constructed of the same type of resin material used to fabricate cover 88, but in this instance may be of somewhat greater cross sectional thickness than sheet 88 in order to withstand the air pressure thereagainst. Operation of the vent structure shown in FIG. 15 is the same as with other embodiments of the invention.
The vent structure embodiments 888 and 689 of FIGS. 16 and 17 respectively are the same as the vent structures 528 of FIG. 11 and 628 of FIG. 14, except that the vents of FIGS. 16 and 17 are in the uppermost part of casing 872 and 673 rather than in the fan deck. The vent 888 therefore has a series of panels 874 identical to apertured panels 574, and a plurality of readily meltable plugs 812 identical to plugs 512.
In like manner, the vent 689 has normally closed, spring biased doors 621 which are identical in construction and operation to doors 620 of FIG. 14. The only difference is the location of doors 621 in openings 611 in the upper part of casing 673, rather than in openings in the fan deck 629. Again, operation of latched doors 621 is identical to the operation previously described with respect to doors 620.
The induced draft crossflow cooling tower 920 shown in FIG. 3 of the drawings is of conventional construction except for the provision of a vented fan deck 928 of identical construction and operation to the vented fan deck 28 of tower 20. The fill assembly 948 of crossflow tower 920 may either comprise individual, side-by-side fill sheets, fill packs similar to the fill packs of tower 20, or in the alternative may be a series of horizontally and vertically spaced splash bars of conventional construction and operation. It is preferred that the components of tower 920 be constructed of the same fire retardant materials previously described in detail with respect to tower 20. In the case of splash bars, these bars are also preferably fabricated of a synthetic resin material having fire retardant properties, such as PVC. Although hot products of combustion rise vertically from a fire within the fill assembly 948 of tower 920, the overlying hot water distribution deck 950 of the tower serves as a barrier thus diverting the flames and/or hot gases toward the fan deck 928, particularly when the fan assembly 932 is functioning. It is to be understood in this respect that the grated fan deck 928 as depicted in FIG. 3 has a central opening similar to opening 31 at the lower end of the fan stack 930. Thus, all plan areas of the fan deck 928 are capable of undergoing venting upon melting of a portion of the relatively low melting temperature synthetic resin sheet material 988 underlying grate unit 980.
The materials of construction for the components of a vented fire resistant cooling tower as described herein preferably have a flame spread rating no greater than about 25 under NFPA test standard 255, or ASTM E84. Materials meeting these standards are defined as limited-combustible under NFPA standard 220.
Burn tests using FM standards (1'×1'×3" deep heptane ignitor) comparing a commercial Marley Class F400 cooling tower (fiberglass composite counterflow cooling tower as depicted in FIG. 1) but without venting, and then an F400 with venting as described and depicted herein, established that the tower without venting burned to the ground, whereas with venting as shown in FIG. 1, only 12% of the available plan area of the tower was damaged. The damage that did occur was confined to the area directly above the ignitor. An approximately 10% maximum fire loss results in a tower that can readily be repaired at reasonable costs. This is especially true in view of the fact for the most part replacement of casing components adjacent to the fire area is all that is required, along with replacement of only those fill packs subjected to the fire, and proximal structural members.
The essential element of the present invention is the fact that the vent structure hereof controls the spread of combustion inside of the tower by limiting heat build up, and minimal damage occurs to the fill assembly because of the way in which a damaged fill pack may fall away from the remainder of the stack into the underlying cold water basin, before there has been any significant lateral profligation of the flame.
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A fire resistant industrial water cooling tower (20) is disclosed having normally closed passive vent structure (28) which vents the interior of the tower (20) above the area which is undergoing combustion to enhance suppression of the fire. The vent area is dependent upon the location and extent of the fire. The vent structure (28) comprises means presenting a series of vent openings which are closed by a component (88) that responds to flames and/or hot products of combustion to move out of blocking relationship to the opening thus venting the interior of the tower. In preferred embodiments, the vent includes a panel member (82) having a series of openings (83) therein which are either covered or blocked by a synthetic resin member (88) formed of a material which will burn and has a relatively low melt temperature thereby causing the material to either burn or rapidly melt when subjected to flames and/or hot products of combustion resulting from a fire in a part of the tower. The fire resistance of an industrial water cooling tower may be further enhanced by the utilization of fill assembly racks (52) made up of individual fill packs (50) that upon burning to a predetermined extent may fall away from the remaining packs of the stack to prevent lateral spread of the fire to the remainder of the fill assembly.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a divisional of U.S. patent application Ser. No. 14/505,787 filed Oct. 3, 2014, the entire content of which is incorporated herein by reference.
TECHNICAL FIELD
[0002] The application relates generally to gas turbines engines combustors and, more particularly, to fuel nozzles.
BACKGROUND
[0003] Gas turbine engine combustors employ a plurality of fuel nozzles to spray fuel into the combustion chamber of the gas turbine engine. The fuel nozzles atomize the fuel and mix it with the air to be combusted in the combustion chamber. The atomization of the fuel and air into finely dispersed particles occurs because the air and fuel are supplied to the nozzle under relatively high pressures. The fuel could be supplied with high pressure for pressure atomizer style or low pressure for air blast style nozzles providing a fine outputted mixture of the air and fuel may help to ensure a more efficient combustion of the mixture. Finer atomization provides better mixing and combustion results, and thus room for improvement exists.
SUMMARY
[0004] There is accordingly provided a method of inducing swirl in pressurized air flowing through an air passageway of a fuel nozzle of a gas turbine engine, the fuel nozzle including the air passageway and a fuel passageway extending through the fuel nozzle and meeting in a mixing zone at a downstream end of the fuel nozzle, the method comprising: inducing swirl in the pressurized air at an exit of the air passageway by directing the pressurised air through helicoidal grooves formed at a downstream end of the air passageway; and directing the swirling pressurized air exiting the air passageway into the mixing zone.
[0005] There is also provided a method of manufacturing a fuel nozzle for a gas turbine engine, the method comprising: providing a fuel nozzle body having an air passageway and a fuel passageway extending axially therethough, the air passageway and the fuel passageway meeting in a mixing zone formed at a downstream end of the fuel nozzle, the mixing zone located downstream of the air passageway and upstream of an exit lip of the fuel nozzle; and forming helicoidal grooves in an outer wall of the air passageway at a downstream end thereof that opens into the mixing zone, the helical grooves adapted to induce swirl in pressurized air flowing through the air passageway and into the mixing zone.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] Reference is now made to the accompanying figures in which:
[0007] FIG. 1 is a schematic cross-sectional view of a gas turbine engine;
[0008] FIG. 2 is a partial schematic cross-sectional view of an embodiment of a nozzle for the combustor of the gas turbine engine of FIG. 1 ; and
[0009] FIG. 3A and 3B illustrate alternative designs of swirl-inducing reliefs of the nozzle of FIG. 2 .
DETAILED DESCRIPTION
[0010] FIG. 1 illustrates a gas turbine engine 10 of a type preferably provided for use in subsonic flight, generally comprising in serial flow communication a fan 12 through which ambient air is propelled, a compressor section 14 for pressurizing the air, a combustor 16 in which the compressed air is mixed with fuel and ignited for generating an annular stream of hot combustion gases, and a turbine section 18 for extracting energy from the combustion gases. The gas turbine engine 10 has one or more fuel nozzles 100 which supply the combustor 16 with the fuel which is combusted with the air in order to generate the hot combustion gases. The fuel nozzle 100 atomizes the fuel and mixes it with the air to be combusted in the combustor 16 . The atomization of the fuel and air into finely dispersed particles occurs because the air and fuel are supplied to the nozzle 100 under relatively high pressures. The fuel could be supplied with high pressure for pressure atomizer style or low pressure for air blast style nozzles providing a fine outputted mixture of the air and fuel may help to ensure a more efficient combustion of the mixture. The nozzle 100 is generally made from a heat resistant metal or alloy because of its position within, or in proximity to, the combustor 16 .
[0011] Turning now to FIG. 2 , an embodiment of a fuel nozzle 100 will be described.
[0012] The nozzle 100 includes generally a cylindrical body 102 defining an axial direction A and a radial direction R. The body 102 is at least partially hollow and defines in its interior a primary air passageway 103 (a.k.a. core air) and a fuel passageway 106 , all extending axially through the body 102 .
[0013] The air passageway 103 and the fuel passageway 106 are aligned with a central axis 110 of the nozzle 100 . The fuel passageway 106 is disposed concentrically around the air passageway 103 . The fuel passageway 106 is annular. It is contemplated that the nozzle 100 could include more than one air passageway 103 and/or fuel passageway 106 , annular or not. The size, shape, and number of the fuel 106 and air passageway 103 may vary depending on the flow requirements of the nozzle 100 , among other factors. The nozzle 100 could, for example, include a secondary passageway around the fuel passageway 106 .
[0014] The body 102 includes an upstream end (not shown) connected to sources of pressurised fuel and air and a downstream end 114 at which the air and fuel exit. The terms “upstream” and “downstream” refer to the direction along which fuel flows through the body 102 . Therefore, the upstream end of the body 102 corresponds to the portion where fuel/air enters the body 102 , and the downstream end 114 corresponds to the portion of the body 102 where fuel/air exits.
[0015] The primary air passageway 103 is defined by outer wall 103 b. The outer wall 103 b ends at exit end 115 . The primary air passageway 103 carries pressurised air illustrated by arrow 116 . The air 116 will be referred interchangeably herein to as “air”, “jet of air”, or “core flow of air”.
[0016] The fuel passageway 106 is defined by inner wall 106 a and outer wall 106 b and carries a fuel film illustrated by arrow 117 . The fuel 117 will be referred interchangeably herein to as “fuel” or “fuel film”. In the embodiment shown in the Figures, the inner wall 106 a has a helicoidal relief to induce swirl in the fuel film 117 . By “swirl”, one should understand any non-streamlined motion of the fluid, e.g. chaotic behavior or turbulence. It is contemplated that the inner wall 106 a could be straight and/or could have grooves/ridges to induce swirl in the fuel film 117 . It is also contemplated that the outer wall 106 b could have grooves/ridges or that the inner wall 106 a could be straight.
[0017] The fuel passage 106 is typically convergent (i.e. its cross-sectional area) may decrease along its length, from inlet to outlet) in the downstream direction at the downstream end 114 . The outer wall 106 b of the fuel passageway 106 converging at the downstream end 114 forces the annular fuel film 117 expelled by the fuel passageways 106 onto a jet of air 116 from the primary air passageway 103 . The outer wall 106 b of the fuel passageway 106 includes a first straight portion 120 , a second converging portion 122 extending from a downstream end 126 of the straight portion 120 , and a third straight portion 124 extending from a downstream end 128 of the converging portion 122 . The third straight portion 124 forms an exit lip 127 of the nozzle 100 . The lip exit 127 is disposed downstream relative to the exit end 115 of the primary air passageway 103 . A diameter D 1 of the outer wall 106 b at the third straight portion 124 is slightly bigger than a diameter D 2 of the outer wall 103 b at the first straight portion 120 .
[0018] A downstream end portion (or exit lip) 132 of the outer wall 103 b of the air passageway 103 includes a surface treatment or swirl-inducing relief in the form of a plurality of grooves 130 . The grooves 130 define a plurality of ridges 131 between them. The ridges 131 form abrupt transitions in the outer wall 103 b and induce swirl in the core flow of air 116 as it exits the air passageway 103 . By inducing swirl to the core air, shearing forces between the fuel film 117 and the air 116 may be increased. The shearing induces better mixing between the air and the fuel, better breakdown of the fuel. In turn, a size of the fuel droplets created may be reduced.
[0019] The grooves 130 in the illustrated embodiment are disposed up to the exit end 115 of the air passageway 103 in order to ensure that the air swirling is sustained to a fuel breakdown region FB, right after the exit of the air passageway 103 at about the third straight portion 124 .
[0020] In the embodiment shown in the Figures, the grooves 130 are circumferential, helicoidal and of round cross-section. It is contemplated that the grooves 130 could have various shapes, for example, the grooves 130 could be axial, circular, of a rectangular cross-section, or of a triangular cross-section. The grooves 130 could be continuous or discontinuous.
[0021] FIGS. 3A and 3B show examples of alternative of designs of the relief of the downstream end portion 132 of the air passageway 130 . Grooves 130 a in FIG. 3A have a sawtooth cross-section, and the grooves in FIG. 3B are replaced by protrusion 130 b extending inwardly from the outer wall 103 b. The protrusions 130 b could also be substitute by vanes, which may be disposed circumferentially along the outer wall 103 b.
[0022] The relief of the outer wall 103 b may have various aspects, as long as it induces some sort of non-streamline behavior, e.g. turbulence, swirl or chaotic behavior in the air 116 . The relief could be right at the exit end 115 of the air passageway 103 , as shown in the Figures, or slightly upstream of the exit end 115 .
[0023] The nozzle 100 may include one or more secondary air passageway(s) sandwiching the fuel film 117 with the core flow of air 116 . The secondary air passageway(s) may include grooves similar to the grooves 130 or protrusion/ridges to induce swirl in the secondary stream of air. The grooves may be of the same type (e.g. helicoid) with the same characteristics (e.g. angle of the helix) as the grooves 130 or could be different.
[0024] The above description is meant to be exemplary only, and one skilled in the art will recognize that changes may be made to the embodiments described without departing from the scope of the invention disclosed. Other modifications which fall within the scope of the present invention will be apparent to those skilled in the art, in light of a review of this disclosure, and such modifications are intended to fall within the appended claims.
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A method of inducing swirl in pressurized air flowing through an air passageway of a fuel nozzle of a gas turbine engine includes inducing swirl in the pressurized air at an exit of the air passageway, by directing the pressurised air through helicoidal grooves formed at a downstream end of the air passageway. The swirling pressurized air exiting the air passageway is then directed into a mixing zone at a downstream end of the fuel nozzle.
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FIELD OF THE INVENTION
[0001] This invention is directed generally to clothes dryers, and more particularly, to safety systems for clothes dryers.
BACKGROUND
[0002] Conventional clothes dryers are constructed of a tumbler configured to hold clothes, a motor for rotating the tumbler, a heating element for heating air, a fan for blowing the heated air across the clothes while the clothes are in the tumbler, and an exhaust conduit for venting the heated air from the dryer. The heating element may be electric or gas powered. Because a close dryer includes a heating element, there always exists the chance of fire. Conventional clothes dryers include many different safety devices for reducing the likelihood of a fire. For instance, a conventional clothes dryer often includes a lint screen for removing lint from the air coming from a tumbler. The lint screen is often placed in an easily accessible location, such as in a slot in a top surface of the clothes dryer, and covers an exhaust conduit where the conduit leaves the tumbler. The lint screen collects lint from the air that has been picked up from the clothing in the tumbler. Most, if not all, manufacturers of clothes dryers recommend that lint screens be cleaned after each load of clothes is dried. Otherwise, an unacceptable amount of lint may build up on the lint screen and pose a fire hazard and prevent efficient operation.
[0003] Clothes dryers also typically contain heat sensors, such as thermocouples, for preventing dryers from overheating and causing fires. Most clothes dryers position a thermocouple proximate to a heating element of the clothes dryer. In this position, the thermocouple is capable of monitoring the area surrounding the heating element and can be used to determine whether the air surrounding the heating element is exceeding a predetermined threshold temperature. If the air becomes too hot, the thermocouple breaks a circuit, which thereby turns the dryer off and prevents the dryer from operating. The temperature of the air surrounding the heating element is monitored because the air surrounding the heating element often becomes too hot for safe operation when an exhaust conduit contains a blockage. Blockages in the exhaust conduits are dangerous because the blockages can cause the heating element to overheat and ignite lint near the heating element.
[0004] Many exhaust hoses for clothes dryers are incorrectly installed such that the exhaust hoses have internal diameters that are too small or are restrained. Such configurations accelerate lint collection on inside surfaces of the exhaust hoses, which may eventually result in partial or total blockage of the exhaust conduit. Such accumulation of lint may occur relatively quickly or over a longer period, such as a few years, and may go unnoticed by a homeowner. Such conditions are extremely dangerous.
[0005] While the conventional configuration of locating a thermocouple proximate to heating elements in a dryer has undoubtedly prevented many fires, dryers having this configuration remain susceptible to fires. In fact, dryers remain one of the most dangerous household appliances. Thus, a need exists for a system for improving the safety of clothes dryers.
SUMMARY OF THE INVENTION
[0006] This invention relates to a restriction sensor system usable with a clothes dryer for identifying blockages in an exhaust conduit downstream of a lint screen in an effort to prevent dangerous conditions and fires. The blockages may be found in the exhaust conduit located inside of or outside of a clothes dryer. The restriction sensor system may include a pressure sensing device for sensing the air pressure in an exhaust conduit of a clothes dryer downstream of a lint screen and creating an alert message when the air pressure on the exhaust conduit exceeds a pre-established threshold air pressure. The pressure sensing device may be formed from a body configured to be coupled to an exhaust conduit of a clothes dryer and may have at least one cavity for containing a diaphragm. The pressure sensing device may also include a diaphragm capable of reacting to relatively small changes in air pressure in the exhaust conduit. The pressure sensing device may also include a sensor for sensing the reactions of the diaphragm. In one embodiment, the sensor may be coupled to the diaphragm. The pressure sensing device may also include an orifice in the body for admitting a gas, such as air, from the exhaust conduit into the cavity of the pressure sensing device.
[0007] The restriction sensor system may also include one or more indicators for indicating that the pressure sensing device has identified that the air pressure in the exhaust conduit of the clothes dryer has exceeded a threshold air pressure. The indicator may be capable of generating a visual alert or an audible alert, or both. The indicator may be configured to be attached to a control panel of a clothes dryer or in another location on a clothes dryer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The accompanying drawings, which are incorporated in and form a part of the specification, illustrate embodiments of the presently disclosed invention and, together with the description, disclose the principles of the invention.
[0009] [0009]FIG. 1 is a perspective view with a partial cut away of a clothes dryer having a restriction sensor system.
[0010] [0010]FIG. 2 is a perspective view of a pressure sensing device usable in the restriction sensor system of FIG. 1.
[0011] [0011]FIG. 3 is an exploded view of the pressure sensing device of FIG. 2.
[0012] [0012]FIG. 4 is a perspective view of another embodiment of a pressure sensing device.
[0013] [0013]FIG. 5 is a side view of another embodiment of a pressure sensing device.
[0014] [0014]FIG. 6 is a top view of the pressure sensing device shown in FIG. 5.
DETAILED DESCRIPTION OF THE INVENTION
[0015] As shown in FIGS. 1 - 4 , this invention is a restriction sensor system 10 for use with an exhaust system 12 of a clothes dryer 14 . Restriction sensor system 10 may be capable of determining whether an exhaust conduit 16 downstream of a lint screen contains a blockage, which could potentially cause unsafe conditions and lead to a fire. Exhaust conduit 16 may include portions of the exhaust system located inside of or outside of clothes dryer 14 , or both. Restriction sensor system 10 may include a pressure sensing device 18 and an indicator 20 for indicating that pressure sensing device 18 has sensed an air pressure exceeding a threshold pressure in exhaust conduit 16 of clothes dryer 14 .
[0016] Pressure sensing device 18 may be capable of determining whether the air pressure in exhaust conduit 16 has exceeded a threshold air pressure, which may indicate that a blockage exists. In one embodiment, pressure sensing device 18 may be a differential pressure monitoring device, as available from Veris Industries in Portland, Oreg. and shown in FIGS. 5 and 6. Exhaust conduit 16 is a conduit downstream of a lint screen, or if a dryer does not contain a lint screen, exhaust conduit 16 is a conduit extending from tumbler 36 to an exit port venting air from clothes dryer 14 . Pressure sensing device 18 may be formed from a body 22 configured to fit into exhaust conduit 16 . Body 22 may contain one or more cavities 24 for containing a diaphragm, as shown in FIG. 3. In at least one embodiment, a diaphragm 26 is positioned in cavity 24 . Diaphragm 26 may be positioned so that a plane 27 in which diaphragm 26 rests is generally orthogonal to a general direction in which air is flowing and striking diaphragm 26 . Diaphragm 26 may be a thin film capable of reacting to small changes in pressure.
[0017] Cavity 24 may be in communication with one or more orifices 28 in body 22 . Orifice 28 may admit air found in exhaust conduit 16 , into cavity 24 . In another embodiment, orifice 28 may be coupled to a conduit 29 for admitting air found in exhaust conduit 16 . Orifice 28 may have any size appropriate for admitting a gas into cavity 24 . Orifice 28 is configured to inhibit contamination by lint or other debris. In one embodiment, orifice 28 and conduit 29 may form a pitot tube or static tube.
[0018] Body 22 may also have a sensor 30 coupled to diaphragm 26 . Sensor 30 may be capable of sensing changes in position of diaphragm 26 that may be caused by changes in pressure in exhaust conduit 16 . Sensor 30 may also be capable of measuring strain in diaphragm 26 . Sensor 30 may be formed from solid-state feedback circuitry.
[0019] Body 22 may further include a fin 32 , as shown in FIG. 4, housing orifice 28 . Fin 32 may be coupled to a bottom side 40 of body 22 . Fin 32 may be sized to accommodate orifice 28 and may have an aerodynamically efficient exterior surface. Fin 32 may include a curved edge 42 extending from the bottom side 40 of body 22 to orifice 28 . In another embodiment, body 32 may not include fin 32 , but instead include only conduit 29 , as shown in FIG. 2. Conduit 29 may have any size appropriate for admitting air into cavity 24 . In one embodiment, restriction sensor system 10 may be configured to position orifice 10 in exhaust conduit 16 so that orifice 28 faces downstream. However, this invention is not limited to positioning orifice 28 in this position. Rather, in another embodiment, restriction sensor system 10 may be positioned so that orifice 28 faces upstream.
[0020] Pressure sensing device 18 may include one or more indicators 20 for indicating that the exhaust conduit 16 has undergone an increase in air pressure that may be caused by, for instance and not by way of limitation, a blockage in exhaust conduit 16 . Indicator 20 may emit a visual alert or an audible alert, or both. Indicator 20 may be a light emitting device (LED) or other visually alerting device. Indicator 20 may also be a speaker, buzzer, or other noise making device. Indicator 20 may be configured to be attached to a control panel 34 of clothes dryer 14 . Indicator 20 may be coupled to sensor 30 using one or more electricity conducting wires 38 . Wires 38 may be connected to connectors 44 .
[0021] In another embodiment, restriction sensor system 10 may include pressure sensing device 18 including diaphragm 26 , as shown in FIGS. 5 and 6, that is configured to be coupled to exhaust conduit 16 of clothes dryer 14 using a conduit rather than coupling the pressure sensing device 18 directly to exhaust conduit 16 . Diaphragm 26 may be a diaphragm having model number RSS-495 that is available from Cleveland Controls of Cleveland, Ohio. The conduit may be coupled to diaphragm 26 at an inlet 35 using connection mechanisms such as, but not limited to, barbs and other devices. The conduit may be mounted directly to a port in exhaust conduit 16 . Alternatively, the conduit may be mounted a device or have an end with a fin 32 . In this embodiment, restriction sensor system 10 may also include sensor 30 in communication with diaphragm 26 and one or more indicators 20 for indicating the pressure in exhaust conduit 16 of clothes dryer 14 . Sensor 30 may be, but is not limited to, a snap-acting switch.
[0022] Restriction sensor system 10 is capable of being installed on any clothes dryer with little modification during a manufacturing process or after a clothes dryer has been completely assembled. The clothes dryer may have a tumbler 36 for containing clothes, a heating element for heating air, a fan for blowing air across the clothes in tumbler 36 , an exhaust conduit 16 for removing heated air, a control panel 34 , and a motor for rotating tumbler 36 . Pressure sensing device 18 may be coupled to exhaust conduit 16 downstream of either a lint screen, or if the clothes dryer does not have a lint screen, down stream of the point at which exhaust conduit 16 couples to tumbler 36 .
[0023] During operation of clothes dryer 14 , lint and other debris is collected with a lint screen. However, lint and other debris often pass through the lint screen and collects in exhaust conduit 16 . Accumulation of lint and other debris in exhaust conduit 16 is a fire hazard. When clothes dryer 14 is operating, air pressure develops in exhaust conduit 16 . As debris collects in clothes dryer 14 , the air pressure in exhaust conduit 16 increases. As the air pressure increases, diaphragm 26 reacts to the change in air pressure. Sensor 30 senses the reaction of diaphragm 26 . When the air pressure in exhaust conduit 16 exceeds a threshold pressure, sensor 30 causes indicator 20 to indicate that exhaust conduit 16 exceeds the threshold pressure. An increase in air pressure in the exhaust system of a clothes dryer may be caused by an increase in lint accumulation.
[0024] Indicator 20 may indicate that an air pressure in excess of a threshold air pressure has been observed by producing a blinking light, a light that is continuously turned on, a noise, such as, but not limited to, a buzzer, a voice that may give instructions on how to check the exhaust conduit, or others. In one embodiment, after sensor 30 determines that a threshold air pressure has been exceeded, indicator 20 remains actuated at all times when clothes dryer 14 is in use until the air pressure subsides to a level beneath the threshold air pressure. The threshold air pressure will vary depending on numerous factors, such as, but not limited to, the diameter of exhaust conduit 16 , the length of exhaust conduit 16 , the presence or absence of a cover on the end of exhaust conduit 16 and other factors. As a result, the threshold air pressure may vary.
[0025] The foregoing is provided for purposes of illustrating, explaining, and describing embodiments of this invention. Modifications and adaptations to these embodiments will be apparent to those skilled in the art and may be made without departing from the scope or spirit of this invention.
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A restriction sensor system for identifying the existence of blockages in exhaust conduits of clothes dryers. The restriction sensor system may include a pressure sensing device having a body configured to be coupled to an exhaust conduit of a clothes dryer. The pressure sensing device may be capable of determining changes in air pressure in the exhaust conduit. Once the air pressure present in the exhaust conduit exceeds a threshold air pressure, the pressure sensing device may send a signal to an indicator to generate an alarm, which may be a visual alarm or audible alarm, or both.
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FIELD OF THE INVENTION
[0001] The present invention relates to a device for preventing dock piling and/or structure piling uplift caused by frost heaving or shifting.
BACKGROUND OF THE INVENTION
[0002] U.S. Pat. No. 4,127,002 relates to a permanent pier piling for use in docks and the like in a body of water whereby an antifreeze solution within the piling circulates to distribute latent ground heat from the lower portion of the piling to the upper portion of the piling to maintain a fluid interface between the piling and the ice during the winter season.
[0003] U.S. Pat. No. 4,464,083 relating to an ice guard for protecting a vertically extending piling positioned in a body of water from damage due to changes in water and ice levels. The ice guard is concentrically positioned around a piling and extends above the surface of the body of water. The ice guard is held in place by the surrounding ice. The ice guard includes at least one longitudinally extending sleeve which is made of a buoyant material and a means for restricting vertical movement of at least a portion of the sleeve. Various longitudinally extending ribs can radiate from the sleeve to enhance adhesion of the sleeve to the ice.
[0004] U.S. Pat. No. 4,818,148 relates to a covering applied on the outer surface of a pile including a steel pipe or the like to surround a predetermined length thereof so as to reduce frost heaving force or negative friction acting on the pile in a frigid area. The covering is closely adhered by an adhesion layer to the pile.
[0005] U.S. Pat. No. 4,585,681 relates to a frost damage proofed pile for installment in a frigid district where the pile is subjected to a freezing and frost heaving force, such as permanently or seasonally frozen soil terrain. A tubular sheath member is fitted over the pile surface and has a length longer than the thickness of an active or seasonally frozen soil layer of the terrain in which the pile is installed. At least a portion of the length of the pile is formed as an extensible section, and at least the lower end of the sheath member is secured to the pile at or below a position corresponding to the bottom region of the active or seasonally frozen soil layer. A fluid material is filled in a space defined between the pile and the sheath member. The frost heaving force caused to exist upon freezing of the active or seasonally frozen soil layer as well as negative friction caused to exist in summer are inhibited from affecting the pile due to sliding of the sheath member relative to the pile.
[0006] U.S. Pat. No. 4,512,683 relates to a sleeve adapted to float in water to surround a piling to protect the same from being lifted by ice. It includes an outer corrugated casing which can be easily gripped by ice forming therearound. Within the casing is a layer of waterproof cementitious material followed by a layer of closed cell foam plastic. The innermost surface of the sleeve, which faces the piling, is a smooth even layer of polyethylene film. Should ice form in the annular space between the piling and the sleeve, the sleeve can easily slide up or down across the outer surface of the ice without moving the piling.
[0007] U.S. Pat. No. 4,403,459 relates to a method and apparatus for installing a benchmark in an arctic region to provide a reference point even after prolonged periods of exposure. To install the benchmark, a hole is formed through the active layer and into the underlying layer. An alignment jig mounts a marker element in a casing and both are positioned into the hole. A leveling clamp on the casing is used to plump and adjust the marker element to a known elevation. The marker element extends to the bottom of the hole while the casing terminates at a depth which is above the bottom of the hole but below the bottom of the active layer. A settable material which will freeze at ambient conditions, is poured into the hole to a point just above the lower end of the casing and is allowed to set. The annulus within the casing around the marker element is filled with fluidic material which will not freeze under ambient conditions. Since the marker element does not directly contact any part of the active layer, the marker element is effectively isolated from contact therewith so that the thawing and refreezing of the active layer do not disturb the position or elevation of the benchmark.
[0008] U.S. Pat. No. 4,784,526 relates to an arctic offshore platform placed in shallow waters with low to moderate ice environments. The arctic offshore platform has one or more support legs. Each support leg includes a base resting on the ocean floor, a central support column extending upward through the base to a portion above the ocean surface and a sloped-sided member seated atop the base and extending upward around the central support column to a position above the ocean surface. The base and central support column are installed and secured to the ocean floor as a unit. The sloped sided member is secured atop the base. The sloped sided member causes the ice sheets which may impact the support leg to fail in flexure, thus reducing the overall ice loadings in the support leg relative to the loading which would exist were the sloped-sided member absent.
SUMMARY OF THE INVENTION
[0009] The present invention relates to a system and method for preventing dock pilings from uplifting due to frozen water and tidal changes and land structure pilings in ground. It is an object of the present invention for the product to slide over the pilings and float partially above the water line. It is an object of the present invention for the device to float approximately 25% above the water line. The present invention comprises a power cord which is wrapped around a piling and plugged into a power source. It is an object of the present invention for the power source to be a 110 volt shore power. It is an object of the present invention for the power source to be located at the dock. The power cord supplies power to a heat trace cable which is enclosed in an air-tight sealed hose. The heat from the trace cable prevents the piling from freezing to the ice beyond the exterior of the heated hose. It is an object of the present invention for the water between the hose and the piling not to freeze. It is an object of the present invention for the internal ice to remain independent from the exterior ice. It is an object of the present invention to keep the piling independent from the strength of the vertical ice.
[0010] It is an object of the present invention for the heated hose to keep the piling independent from the force of the rising tide. This prevents upward lift.
[0011] It is an object of the present invention to provide a rigid hose. It is an object of the present invention for the heated hose to be attached to a plastic tube. It is an object of the present invention for the plastic tube to be about 4 feet long. It is an object of the present invention for the plastic tube or pipe to be about 10″-15″ in diameter.
[0012] The present invention relates to a method of protecting a piling against uplifting comprising: installing a heat trace cable inside a hose. The hose is then sealed air tight. The air tight seal allows for buoyancy of the device. Both sealed ends of the heated hose will remain above the water line or ground line. One end of the hose is capped closed, while the other end is sealed with the power cord that is plugged into the shore power. It is an object of the present invention to provide a thermostat adapter.
[0013] It is an object of the present invention for the device to be the flexible type. It is an object of the present invention for the device to protect any size piling or joined pilings. It is an object of the present invention for the device to be installed on pilings attached to docks or on land structures. It is an object of the present invention for the heat hose to be wrapped around the piling or joined pilings. It is an object of the present invention for the flexible heated hose to be wrapped around the piling without disturbing any hardware.
[0014] It is an object of the present invention to provide a device for preventing pilings from shifting or lifting in the frozen ground. The present invention relates to a device which prevents land pilings from uplifting due to frost heaving or shifting comprising a power cord which is wrapped around a piling and plugged into a power source. It is an object of the present invention for the device to be located 25% above the ground.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a side view of the device of the present invention wrapped around a dock piling.
[0016] FIG. 2 is a top view showing the device of the present invention wrapped around a dock piling.
[0017] FIG. 3 shows a plastic tube or plastic pipe used in the device of the present invention.
[0018] FIG. 4 shows the device of the present invention.
[0019] FIG. 5 shows a side view showing multiple devices of the present invention used on a dock.
[0020] FIG. 6 shows a side view showing multiple devices of the present invention used for land pilings.
DETAILED DESCRIPTION OF THE INVENTION
[0021] FIG. 1 shows the device 10 slid over the piling 20 and floating approximately 25% above the water line, and 75% below the water line. The power cord 30 is plugged into a 110 volt shore power on the dock 40 . The power cord 30 supplies power to a heat trace cable which is enclosed in an air-tight sealed hose. The heat from the heat trace cable prevents the piling from freezing to the ice beyond the exterior of the heated hose.
[0022] FIG. 2 shows a top view of the device 100 which has a heated hose 110 . Using the device of the present invention the water 120 between the hose 110 and the piling 130 does not freeze. Ice may begin to form at the water's surface, from the piling 130 toward the interior of the heated hose 110 , but the internal ice 120 remains independent from the exterior ice 140 . The device of the present invention keeps the piling independent from the massive strength of the vertical ice movement. While the tide may rise and fall when ice is attached to the piling 130 , the heated hose 110 keeps the piling 130 independent from the force of the rising tide. This prevents any upward lift.
[0023] FIG. 3 shows an embodiment of a rigid type, wherein the heated hose is attached to a plastic tube or plastic pipe 200 which is approximately 4 feet long and 10″-15″ in width. FIG. 4 shows the tube 200 having the power cord 210 inside of it. In a preferred embodiment, the tube stays 25% above the water line and 75% below the water line.
[0024] First the heat trace cable is installed inside the hose. The hose is then sealed, one end capped 220 , and the other end will have the power cord 210 that will be plugged into the shore power. The air-tight seal allows for the buoyancy of the product. Both sealed ends of the heated hose will remain above the water line. The heated hose is then wrapped around the tube. The unit is then ready for installation. In a preferred embodiment, thermostat adapter plugs are available.
[0025] FIG. 5 shows a side view of a floating dock or boardwalk 300 , showing multiple devices 310 . FIG. 5 shows an embodiment wherein the device 310 are flexible. With the flexible type, the user has the advantage of protecting any size piling or joined pilings 320 . The flexible type allows installation on pilings attached to docks. With the flexible type, the heated hose 330 can simply be wrapped around the piling 320 , or joined pilings. Many pilings at boat slips have hardware mounted to them. In this case, the flexible heated hose can be wrapped around the piling without disturbing the hardware.
[0026] FIG. 6 shows a side view of a bottom support beam or structure 400 having multiple devices 425 attached to pilings 410 . The device 425 preferably is approximately 75% below the ground 420 and 25% above the ground in the crawlspace 430 . Plug 440 is attached to a device for providing power to the device 425 .
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The present invention relates to a device for preventing dock piling and/or structure piling uplift caused by frost heaving or shifting.
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TECHNICAL FIELD
[0001] The present invention relates to an improved composition for use in the protection of non-metallic inorganic materials such as glassware in an automatic dishwashing (ADW) process.
BACKGROUND
[0002] The problem of corrosion of non-metallic inorganic items, such as glassware, ceramic and enamel materials, when subjected to automatic dishwashing processes is well recognised in the art. For example, it has been proposed that the problem of glassware corrosion is the result of two separate phenomena. Firstly, it has been suggested that the corrosion is due to leakage of minerals from the glass network, accompanied by hydrolysis of the silicate network. Secondly, it is proposed that the silicate material is then released from the glass.
[0003] These phenomena can cause damage to glassware after a number of separate wash cycles. The damage may include cloudiness, scratches, streaks and other discoloration/detrimental effects. The damage is generally irreversible and over time can be detected as a loss in mass of the glassware. This is in contrast to the cloudiness, streaks or spotting that may result from deposition of substances on the surface of the glassware, which can appear after a single wash cycle, and is generally removable.
[0004] Silicate materials have been proposed as agents that are effective in preventing materials from being released by the glass composition. However, the use of silicate compounds can have detrimental side effects, such as the tendency to increase separation of silicate material at the glass surface.
[0005] A further solution has been to use metals such as zinc, either in metallic form (such as described in U.S. Pat. No. 3,677,820) or in the form of compounds. The use of soluble zinc compounds in the prevention of glassware corrosion in a dishwasher is described in, for example, U.S. Pat. No. 3,255,117.
[0006] European Patents; EP-A-0 383 480, EP-A-0 383 482 and EP-A-0 387 997) describe the use of water insoluble compounds including zinc silicate, zinc carbonate, basic zinc carbonate (Zn 2 (OH) 2 CO 3 ), zinc hydroxide, zinc oxalate, zinc monophosphate (Zn 3 (PO 4 ) 2 ) and zinc pyrophosphate (Zn 2 P 2 O 7 ) for this purpose.
[0007] However, it has been found that the use of heavy metal compounds in some circumstances reduce the bleaching performance of a dishwashing composition on bleachable stains such as tea stains. Furthermore, for environmental reasons, it is becoming increasingly desirable to limit (and especially to avoid) the use of heavy metals in detergent formulations.
[0008] WO2010/020765 proposed a solution to this problem of glass and tableware erosion that did not require the use of heavy metals. This document, which is hereby incorporated by reference, disclosed that polyalkyleneimines such as polyethyleneimine (PEI) were highly effective additives for the prevention of corrosion of non-metallic inorganic items in automatic washing machines. WO2012/153143 also discloses ADW compositions that contain PEI for inhibiting glassware corrosion.
[0009] WO 99/07815 discusses the use of PEI as a sequestrant in detergents, for the purpose of stain removal, preferably in laundry detergents that are substantially free of bleach. Aqueous liquid laundry detergents are amongst the compositions disclosed.
[0010] It has been increasingly found by the applicants that lower and lower amounts of PEI can be added to ADW detergent compositions whilst maintaining protection against glassware corrosion. PEI may be added in doses equivalent to between 1 to 10 mg per wash cycle, whilst still maintaining full glassware protecting performance.
[0011] Polyethyleneimines can be solid or liquid compounds at room temperature, depending on their structure. For the field of automatic dishwashing, a number of liquid PEls are particularly of interest. However, it is extremely challenging to formulate a liquid form of PEI homogenously at very low levels into an automatic dishwashing detergent.
[0012] The applicants have found that applying low levels of PEI to solid powders or granules is difficult and can result in inconsistent distribution of the material throughout the solid. PEls are strongly surface active and binding materials. This means that the levels of PEI can vary significantly from wash to wash in powdered detergent and other solid monodose formats, leading to inconsistent results when formulating such products on an industrial scale.
[0013] The applicants have found that a good way to reliably prepare low level PEI-containing ADW compositions is to formulate the PEI in a gel or liquid phase of the composition. In this way the PEI seems to be evenly distributed and available in wash conditions to protect glassware.
STATEMENTS OF INVENTION
[0014] In a first aspect of the invention there is provided an automatic dishwasher (ADVV) detergent composition comprising less than 1% by weight of a Polyethylene imine (PEI) wherein the PEI is contained within a gel or liquid phase of the ADW detergent composition.
[0015] In a second aspect of the invention, there is provided a composition as recited in claim 1 .
[0016] In a third aspect of the invention, there is provided a product comprising the composition according to the invention in its first or second aspect, housed within a water soluble or water dispersible film or container.
[0017] In a fourth aspect of the invention, there is provided a method of automatic dishwashing, comprising supplying a composition according to the invention in its first or second aspect, or a product according to the invention in its third aspect, to an automatic dishwasher, and releasing the composition or product into a wash cycle of the automatic dishwasher.
[0018] In a fifth aspect of the invention, there is provided the use of a composition according to the invention in its first or second aspect, or a product according to the invention in its third aspect, for cleaning glassware whilst inhibiting the corrosion of the glassware during automatic dishwashing.
DETAILED DESCRIPTION
[0019] In the following section, embodiments discussed apply equally to all aspects of the invention unless the context dictates otherwise. Amounts quoted are by weight (wt %) unless stated otherwise.
[0020] Herein, term “phase” is preferably not interpreted in the strict thermodynamic sense. For example, the liquid “phase” may also comprise suspended solids, i.e. it may be a suspension or paste. Preferably, it is homogeneous on the macroscopic scale and/or is spatially separated from any other “phases” present.
[0021] For the purposes of the present invention, gel form is preferred. Herein, the term gel is not limited to a strictly colloidal composition. For the purposes of the present invention, gel may be considered to be a thickened liquid.
[0022] When a less viscous gel precursor material is used for processing ease, it preferably becomes more viscous, and preferably sets to become shape-stable, on standing.
[0023] In this embodiment, the gel precursor is preferably already gel itself, suitably a viscous material but flowable, either under gravity or when pumped. Preferably its viscosity when introduced is at least 1,000 mPa·s., preferably at least 5,000 mPa·s., preferably at least 10,000 mPa·s., measured at 25° C. on a Brookfield viscometer, RVDV-II+, spindle no. 27, speed 2.5 rpm.
Product Format
[0024] The entire ADW composition does not need to be in liquid or gel form, although it may be. The ADW composition may be comprised of several different phases, at least one of which may be in a liquid or gel form, provided that the liquid or gel form contains PEI. Detergent phases in the prior art include tablets, powders, gels, pastes and liquids. The detergent compositions of the present invention may comprise a mixture of two or more phases as long as at least one is a gel or liquid phase. For example the composition may comprise a gel or liquid component and a free powder component. The PEI may be entirely contained within the gel or liquid portion, or contained within both portions.
[0025] In an embodiment, the ADW detergent composition is a multi-phase composition with at least two or more separate phases, preferably at least three or more separate phases. In an embodiment, the composition comprises one or more different phases including powder, granules, and compressed solids.
[0026] Preferably the ADW compositions of the present invention are monodose compositions, i.e. compositions pre-supplied in the quantity required for a single wash cycle.
[0027] The monodose composition may comprise a tablet with a gel portion or layer. If compressed tablets form a portion of the ADW detergent composition, they may be homogeneous or composed of multi-layers. If the tablets are multi-layered then different layers may comprise different parts of the detergent composition. This may be done to increase stability or increase performance, or both.
[0028] In an embodiment, the composition is contained within a water soluble film or container, preferably a polyvinylalcohol film or container. The ADW detergent compositions may be housed in PVOH rigid capsules or film blisters. These PVOH capsules or blisters may have a single compartment or may be multi-compartment.
[0029] Multi-compartment blisters or capsules may have different portions of the composition in each compartment, or the same composition in each compartment. The distinct regions/compartments may contain any proportion of the total amount of ingredients as desired.
[0030] The PVOH capsules or film blisters may be filled with tablets, powders, gels, pastes or liquids, or combinations of these, within the scope of the invention.
[0031] The monodose may comprise an injection moulded PVOH capsule with multiple compartments. Each compartment may comprise a different composition. At least one of the compartments will contain a gel or liquid composition and at least a portion of the PEI will be in this composition and preferably all of the PEI will be in this composition.
Polyethyleneimine
[0032] The polyethyleneimine (PEI) is contained within a gel or liquid phase of the composition, and the amount of the polyethyleneimine is less than 1% by weight of the composition. Preferably, where the composition is multi-phase, the polyethyleneimine is only present in the gel or liquid phase.
[0033] Preferably the lowest amount of PEI to achieve effective results will be used. In an embodiment, the PEI comprises less than 0.5% by weight of the composition, preferably less than 0.25% by weight of the composition and most preferably less than 0.05%. Preferably, the PEI comprises less than 0.005% and preferably less than 0.0025% by weight of the composition. In an embodiment, the PEI loading is less than 0.0005% by weight.
[0034] Preferably the amount of PEI used will be between 0.5 mg and 100 mg per wash, more preferably between 1 mg and 50 mg, more preferably between 2 mg and 25 mg, most preferably between 4 and 10 mg.
[0035] In an embodiment, the composition comprises at least 0.0001 wt % of the PEI and/or less than 0.5 wt %, less than 0.25 wt %, less than 0.05 wt %, less than 0.04 wt %, less than 0.03 wt %, less than 0.01 wt %, less than 0.005 wt %, or less than 0.0025 wt %, of the PEI.
[0036] While it has been found that the PEI used may have any formula weight for effectiveness, preferably the PEI has a lower formula weight. Preferably the PEI used in the present invention has a formula weight between 100 and 50,000, more preferably between 400 and 25,000, more preferably between 800 and 10,000 and most preferably between 1000 and 3000. In an embodiment, the PEI has a molecular weight between 100 and 2500, preferably 200 and 1500 and most preferably between 400 and 1200. In an embodiment, the molecular weight of the PEI is between 700 and 900. The most preferred PEI has a molecular weight of 800. The molecular weight is suitably determined by light scattering.
[0037] Any PEI may be used. The PEI may be branched or linear. Preferably, the PEI is branched. Preferably, it contains primary, secondary and tertiary amine groups, and preferably has a ratio of primary to secondary amine groups between 1:0.5 and 1:1, preferably between 1:0.7 and 1:0.9.
[0038] Preferably, the PEI is liquid at room temperature.
[0039] Preferably, the PEI contains no alkoxylate groups or is homopolymeric.
[0040] A particularly preferred PEI is Lupasol® FG which is supplied by BASF.
Solvent
[0041] Water may be included in the ADW detergent composition. Preferably, however, the gel or liquid phase comprising the PEI is non-aqueous. In an embodiment, the gel or liquid phase contains no more than 10%, no more than 5%, no more than 3%, no more than 1%, or no, water, by weight of the gel or liquid phase.
[0042] The gel or liquid phase may contain organic solvents, preferably water-miscible solvents.
Surfactant
[0043] Surfactant may also be included in the ADW detergent composition and any of nonionic, anionic, cationic, amphoteric or zwitterionic surface active agents or suitable mixtures thereof may be used. Many such suitable surfactants are described in Kirk Othmer's Encyclopedia of Chemical Technology, 3rd Ed., Vol. 22, pp. 360-379, “Surfactants and Detersive Systems”, incorporated by reference herein. In general, bleach-stable surfactants are preferred according to the present invention.
[0044] In the case of ADW compositions, it is preferred to minimise the amount of anionic surfactant. Preferably the composition comprises no more than 2 wt %, no more than 1 wt %, or no, anionic surfactant. Preferably the composition comprises no more than 2 wt %, no more than 1 wt %, or no, ionic surfactant of any type. Non-ionic surfactants are especially preferred instead for automatic dishwashing compositions.
[0045] A preferred class of non-ionic surfactants is ethoxylated non-ionic surfactants prepared by the reaction of a monohydroxy alkanol or alkylphenol with 6 to 20 carbon atoms. Preferably the surfactants have at least 12 moles, particularly preferred at least 16 moles, and still more preferred at least 20 moles, such as at least 25 moles, of ethylene oxide per mole of alcohol or alkylphenol.
[0046] Particularly preferred non-ionic surfactants are the non-ionics from a linear chain fatty alcohol with 16-20 carbon atoms and at least 12 moles, particularly preferred at least 16 and still more preferred at least 20 moles, of ethylene oxide per mole of alcohol.
[0047] According to one embodiment of the invention, the non-ionic surfactants additionally may comprise propylene oxide units in the molecule. Preferably these PO units constitute up to 25% by weight, preferably up to 20% by weight, and still more preferably up to 15% by weight of the overall molecular weight of the non-ionic surfactant.
[0048] Surfactants which are ethoxylated mono-hydroxy alkanols or alkylphenols, which additionally comprises polyoxyethylene-polyoxypropylene block copolymer units may be used. The alcohol or alkylphenol portion of such surfactants constitutes more than 30% by weight, preferably more than 50% by weight, more preferably more than 70% by weight of the overall molecular weight of the non-ionic surfactant.
[0049] Another class of suitable non-ionic surfactants includes reverse block copolymers of polyoxyethylene and polyoxypropylene and block copolymers of polyoxyethylene and polyoxypropylene initiated with trimethylolpropane.
[0050] Another preferred class of nonionic surfactant can be described by the formula:
[0000] R 1 O[CH 2 CH(CH 3 )O] x [CH 2 CH 2 O] y [CH 2 CH(OH)R 2 ]
[0000] where R 1 represents a linear or branched chain aliphatic hydrocarbon group with 4-18 carbon atoms or mixtures thereof, R 2 represents a linear or branched chain aliphatic hydrocarbon rest with 2-26 carbon atoms or mixtures thereof, x is a value between 0.5 and 1.5, and y is a value of at least 15.
[0051] Another group of preferred non-ionic surfactants are the end-capped polyoxyalkylated non-ionics of formula:
[0000] R 1 O[CH 2 CH(R 3 ) O] x [CH 2 ] k CH(OH)[CH 2 ] j OR 2
[0000] where R 1 and R 2 represent linear or branched chain, saturated or unsaturated, aliphatic or aromatic hydrocarbon groups with 1-30 carbon atoms, R 3 represents a hydrogen atom or a methyl, ethyl, n-propyl, iso-propyl, n-butyl, 2-butyl or 2-methyl-2-butyl group, x is a value between 1 and 30 and, k and j are values between 1 and 12, preferably between 1 and 5. When the value of x is>2 each R 3 in the formula above can be different. R 1 and R 2 are preferably linear or branched chain, saturated or unsaturated, aliphatic or aromatic hydrocarbon groups with 6-22 carbon atoms, where group with 8 to 18 carbon atoms are particularly preferred. For the group R 3 , H, methyl or ethyl is particularly preferred. Particularly preferred values for x are comprised between 1 and 20, preferably between 6 and 15.
[0052] As described above, in case x>2, each R 3 in the formula can be different. For instance, when x=3, the group R 3 could be chosen to build ethylene oxide (R 3 ═H) or propylene oxide (R 3 =methyl) units which can be used in every single order for instance (PO)(EO)(EO), (EO)(PO)(EO), (EO)(EO)(PO), (EO)(EO)(EO), (PO)(EO)(PO), (PO)(PO)(EO) and (PO)(PO)(PO). The value 3 for x is only an example and bigger values can be chosen whereby a higher number of variations of (EO) or (PO) units would arise.
[0053] Particularly preferred end-capped polyoxyalkylated alcohols of the above formula are those where k=1 and j=1 originating molecules of simplified formula:
[0000] R 1 O[CH 2 CH(R 3 )O] x CH 2 CH(OH)CH 2 OR 2
[0054] The use of mixtures of different non-ionic surfactants is suitable in the context of the present invention, for instance mixtures of alkoxylated alcohols and hydroxy group containing alkoxylated alcohols.
[0055] Other suitable surfactants are disclosed in WO 95/01416, to the contents of which express reference is hereby made.
[0056] Preferably the non-ionic surfactants are present in the detergent composition in an amount of from 0.1% by weight to 20% by weight, more preferably 1% by weight to 15% by weight, such as 2% to 10% by weight, based on the total weight of the detergent composition.
[0057] In an embodiment, the gel or liquid phase comprising the PEI further comprises at least 10%, at least 15%, at least 20%, or at least 25%, surfactant, preferably non-ionic surfactant, by weight of the gel or liquid phase.
[0058] In an embodiment, a gel composition comprises between 30 and 80% non-ionic surfactants, 5-35% solvents, 0.1-5% and 0-10% water.
Builders
[0059] The detergent compositions may comprise a builder (or co-builder). In an embodiment, the liquid or gel phase comprises no builder. In an embodiment in which the composition is multi-phase, the builder is included in a separate phase from the PEI.
[0060] The builder/co-builder may be either a phosphorous-containing builder or a phosphorous-free builder as desired. In many jurisdictions, phosphate builders are banned. In an embodiment, the composition is phosphate-free.
[0061] If phosphorous-containing builders are to be used it is preferred that mono-phosphates, di-phosphates, tri-polyphosphates or oligomeric-polyphosphates are used. The alkali metal salts of these compounds are preferred, in particular the sodium salts. An especially preferred builder is sodium tripolyphosphate (STPP). Conventional amounts of the phosphorous-containing builders may be used typically in the range of from 15% by weight to 60% by weight, such as from 20% by weight to 50% by weight or from 25% by weight to 40% by weight.
[0062] If phosphorous-free builder is included, it is preferably chosen from succinate based compounds. The terms ‘succinate based compound’ and ‘succinic acid based compound’ are used interchangeably herein. Conventional amounts of the succinate based compounds may be used, typically in the range of from 5% by weight to 80% by weight, such as from 15% by weight to 70% by weight or from 20% by weight to 60% by weight. The compounds may be used individually or as a mixture.
[0063] Other suitable builders are described in U.S. Pat. No. 6,426,229 which are incorporated by reference herein. Particular suitable builders include; for example, aspartic acid-N-monoacetic acid (ASMA), aspartic acid-N,N-diacetic acid (ASDA), aspartic acid-N-monopropionic acid (ASMP), iminodisuccinic acid (IDA), N-(2-sulfomethyl) aspartic acid (SMAS), N-(2-sulfoethyl)aspartic acid (SEAS), N-(2-sulfomethyl)glutamic acid (SMGL), N-(2-sulfoethyl)glutamic acid (SEGL), N-methyliminodiacetic acid (MIDA), α-alanine-N,N-diacetic acid (α-ALDA), β-alanine-N,N-diacetic acid (β-ALDA), serine-N,N-diacetic acid (SEDA), isoserine-N,N-diacetic acid (ISDA), phenylalanine-N,N-diacetic acid (PHDA), anthranilic acid-N,N-diacetic acid (ANDA), sulfanilic acid-N,N-diacetic acid (SLDA), taurine-N, N-diacetic acid (TUDA) and sulfomethyl-N,N-diacetic acid (SMDA) and alkali metal salts or ammonium salts thereof.
[0064] Further preferred succinate compounds are described in U.S. Pat. No 5,977,053 and have the formula:
[0000]
[0000] in which R, R 1 , independently of one another, denote H or OH, R 2 , R 3 , R 4 , R 5 , independently of one another, denote a cation, hydrogen, alkali metal ions and ammonium ions, ammonium ions having the general formula R 6 R 7 R 8 R 9 N+ and R 6 , R 7 , R 8 , R 9 , independently of one another, denoting hydrogen, alkyl radicals having 1 to 12 C atoms or hydroxyl-substituted alkyl radicals having 2 to 3 C atoms.
[0065] Preferred examples include tetrasodium imminosuccinate. Iminodisuccinic acid (IDS) and (hydroxy)iminodisuccinic acid (HIDS) and alkali metal salts or ammonium salts thereof are especially preferred succinate based builder salts.
[0066] The phosphorous-free co-builder may also or alternatively comprise non-polymeric organic molecules with carboxylic group(s). Builder compounds which are organic molecules containing carboxylic groups include citric acid, fumaric acid, tartaric acid, maleic acid, lactic acid and salts thereof. In particular the alkali or alkaline earth metal salts of these organic compounds may be used, and especially the sodium salts. An especially preferred phosphorous-free builder is sodium citrate. Such polycarboxylates which comprise two carboxyl groups include, for example, water-soluble salts of, malonic acid, (ethylenedioxy)diacetic acid, maleic acid, diglycolic acid, tartaric acid, tartronic acid and fumaric acid. Such polycarboxylates which contain three carboxyl groups include, for example, water-soluble citrate. Correspondingly, a suitable hydroxycarboxylic acid is, for example, citric acid.
[0067] Three other highly preferred builders are MGDA, GLDA and malonyl lactate.
[0068] Preferred secondary builders include homopolymers and copolymers of polycarboxylic acids and their partially or completely neutralized salts, monomeric polycarboxylic acids and hydroxycarboxylic acids and their salts, phosphates and phosphonates, and mixtures of such substances. Preferred salts of the abovementioned compounds are the ammonium and/or alkali metal salts, i.e. the lithium, sodium, and potassium salts, and particularly preferred salts is the sodium salts. Secondary builders which are organic are preferred. A polymeric polycarboxylic acid is the homopolymer of acrylic acid. Other suitable secondary builders are disclosed in WO 95/01416, to the contents of which express reference is hereby made.
[0069] Preferably the total amount of builder present in the composition is at least 20% by weight, and most preferably at least 25% by weight, preferably in an amount of up to 70% by weight, preferably up to 60% by weight, more preferably up to 45% by weight. The actual amount used in the compositions will depend upon the nature of the builder used. If desired a combination of phosphorous-containing and phosphorous-free builders may be used.
Bleaches
[0070] The detergent compositions may comprise a bleach component or material. For example, the bleach material may comprise and oxygen or chlorine based bleach. The bleach material may be selected from any conventional bleach material known to be used in detergent compositions. The material may comprise the active bleach species itself or a precursor to that species. For example, the bleach material may comprise at least one inorganic peroxide or organic peracid or a chlorine based bleach including derivatives and salts thereof or mixtures thereof. Inorganic peroxides include percarbonates, perborates, persulphates, hydrogen peroxide and derivatives and salts thereof. The sodium and potassium salts of these inorganic peroxides are suitable, especially the sodium salts. Sodium percarbonate and sodium perborate are most preferred, especially sodium percarbonate.
[0071] The detergent compositions may also comprise bleach additives or bleach activation catalysts. The composition may preferably comprise one or more bleach activators or bleach catalysts depending upon the nature of the bleaching compound. Any suitable bleach activator may be included, for example TAED, if this is desired for the activation of the bleach material. Any suitable bleach catalyst may be used, for example manganese acetate or dinuclear manganese complexes such as those described in EP-A-1,741,774. The organic peracids such as perbenzoic acid and peroxycarboxylic acids e.g. PAP do not require the use of a bleach activator or catalyst as these bleaches are active at relatively low temperatures such as about 30° C. and this contributes to such bleach materials being especially preferred according to the present invention.
[0072] In an embodiment, the composition does not comprise bleach (and preferably does not comprise a bleach activator or bleach catalyst either) in the same liquid or gel phase as the PEI.
Other Ingredients
[0073] The skilled person will be aware of the kinds of ingredients needed to form effective ADW (automatic dishwashing) detergent compositions. The detergent compositions may comprise any other suitable ingredients known in the art.
[0074] For example, the detergent compositions may include enzymes. It is preferred that the enzyme is selected from proteases, lipases, amylases, cellulases and peroxidases, with proteases and amylases, especially proteases being most preferred. It is most preferred that protease and/or amylase enzymes are included in the compositions according to the invention as such enzymes are especially effective in dishwashing detergent compositions. Any suitable species of these enzymes may be used as desired. More than one species may be used.
[0075] The ADW detergent compositions may comprise one or more additional anti-corrosion agents. These anti-corrosion agents may provide further benefits against corrosion of glass and/or metal and the term encompasses agents that are intended to prevent or reduce the tarnishing of non-ferrous metals, in particular of silver and copper.
[0076] It is known to include a source of multivalent ions in detergent compositions, and in particular in automatic dishwashing compositions, for anti-corrosion benefits. For example, multivalent ions and especially zinc, bismuth and/or manganese ions have been included for their ability to inhibit such corrosion. Organic and inorganic redox-active substances which are known as suitable for use as silver/copper corrosion inhibitors are mentioned in WO 94/26860 and WO 94/26859. Suitable inorganic redox-active substances are, for example, metal salts and/or metal complexes chosen from the group consisting of zinc, bismuth, manganese, titanium, zirconium, hafnium, vanadium, cobalt and cerium salts and/or complexes, the metals being in one of the oxidation states II, Ill, IV, V or VI. Particularly suitable metal salts and/or metal complexes are chosen from the group consisting of MnSO4, Mn(II) citrate, Mn(II) stearate, Mn(II) acetylacetonate, Mn(II) [1-hydroxyethane-1,1-diphosphonate], V 2 O 5 , V 2 O 4 , VO 2 , TiOSO 4 , K 2 TiF 6 , K 2 ZrF 6 , CoSO 4 , Co(NO 3 ) 2 , Zinc acetate, zinc sulphate and Ce(NO 3 ) 3 . Any suitable source of multivalent ions may be used, with the source preferably being chosen from sulphates, carbonates, acetates, gluconates and metal-protein compounds. Zinc salts are especially preferred corrosion inhibitors.
[0077] Preferred silver/copper anti-corrosion agents are benzotriazole (BTA) or bis-benzotriazole and substituted derivatives thereof. Other suitable agents are organic and/or inorganic redox-active substances and paraffin oil. Benzotriazole derivatives are those compounds in which the available substitution sites on the aromatic ring are partially or completely substituted. Suitable substituents are linear or branch-chain C 1-20 alkyl groups and hydroxyl, thio, phenyl or halogen such as fluorine, chlorine, bromine and iodine. A preferred substituted benzotriazole is tolyltriazole.
[0078] Any conventional amount of the anti-corrosion agents may be included. However, it is preferred that they are present in an total amount of from 0.01% by weight to 5% by weight, preferably 0.05% by weight to 3% by weight, more preferably 0.1% by weight to 2.5% by weight, such as 0.2% by weight to 2% by weight based on the total weight.
[0079] Polymers intended to improve the cleaning performance of the detergent compositions may also be included therein. For example sulphonated polymers may be used.
[0080] Preferred examples include copolymers of CH2=CR 1 —CR 2 R 3 —O—C 4 H 3 R 4 SO 3 X wherein R 1 , R 2 , R 3 , R 4 are independently 1 to 6 carbon alkyl or hydrogen, and X is hydrogen or alkali with any suitable other monomer units including modified acrylic, fumaric, maleic, itaconic, aconitic, mesaconic, citraconic and methylenemalonic acid or their salts, maleic anhydride, acrylamide, alkylene, vinylmethyl ether, styrene and any mixtures thereof. Other suitable sulfonated monomers for incorporation in sulfonated (co)polymers are 2-acrylamido-2-methyl-1-propanesulphonic acid, 2-methacrylamido-2-methyl-1-propanesulphonic acid, 3-methacrylamido-2-hydroxy-propanesulphonic acid, allysulphonic acid, methallysulphonic acid, 2-hydroxy-3-(2-propenyloxy) propanesulphonic acid, 2-methyl-2-propenen-1-sulphonic acid, styrenesul phonic acid, vinylsulphonic acid, 3-sulphopropyl acrylate, 3-sulphopropylmethacrylate, sulphomethylacrylamide, sulphomethylmethacrylamide and water soluble salts thereof. Suitable sulphonated polymers are also described in U.S. Pat. No 5,308,532 and in WO 2005/090541.
[0081] When a sulfonated polymer is present, it is preferably present in an amount of at least 0.1% by weight, preferably at least 0.5% by weight, more preferably at least 1% by weight, and most preferably at least 3% by weight, up to 40% by weight, preferably up to 25% by weight, more preferably up to 15% by weight, and most preferably up to 10% by weight.
[0082] The detergent composition may also comprise one or more foam control agents. Suitable foam control agents for this purpose are all those conventionally used in this field, such as, for example, silicones and their derivatives and paraffin oil. The foam control agents are preferably present in amounts of 0.5% by weight or less.
[0083] The detergent compositions may also comprise minor, conventional, amounts of preservatives, fragrance etc.
[0000] pH
[0084] The ADW detergent compositions may also comprise a source of acidity or a source of alkalinity, to obtain the desired pH, on dissolution, especially if the composition is to be used in an automatic dishwashing application. A source of acidity may suitably be any suitable acidic compound for example a polycarboxylic acid. For example a source of alkalinity may be a carbonate or bicarbonate (such as the alkali metal or alkaline earth metal salts). A source of alkalinity may suitably be any suitable basic compound for example any salt of a strong base and a weak acid. When an alkaline composition is desired silicates are amongst the suitable sources of alkalinity. Preferred silicates are sodium silicates such as sodium disilicate, sodium metasilicate and crystalline phyllosilicates. In an embodiment, the composition is free of silicates.
[0085] In an embodiment, the composition has a pH between 6 and 13, between 6.5 and 12, between 7 and 11 or between 8 and 10.
[0086] The invention is further described with reference to the following non-limiting examples. Further examples within the scope of the invention will be apparent to the person skilled in the art.
EXAMPLES
Example 1
[0087] A three phase monodose composition, housed in a three-chambered PVOH capsule was prepared.
[0088] Powder formula 1 in compartment 1, dosage 11 g:
[0000]
MGDA
25%
Sodium carbonate
30%
Sodium percarbonate
20%
Citric acid
10%
Solid surfactant
15%
[0089] Powder formula 2 in compartment 3, dosage 1.3 g:
[0000]
Bleach Activator (TAED)
25%
sodium carbonate
25%
Cobuilders (Polyacrylates,
22%
Phosphonates)
Protease
23%
Amylase
5%
[0090] Gel with glass protection agent, dosage 1.8 g:
[0000]
Glycerin
90.6%
Gelatin
6%
Lupasol ® FG (PEI,
0.4%
molecular weight 800)
Water + Dye
3%
[0091] Total PEI content: 7.6 mg per unit dose.
Example 2
[0092] Phosphate containing three-part composition in a three-chambered PVOH pouch.
[0093] Powder formula 1-16 grams
[0000]
STPP
48.70%
Sodium carbonate
16.00%
Trisodium citrate
22.00%
Benzotriazol
0.40%
HEDP
0.30%
Protease
1.50%
Amylase
1.00%
1,2 Propylenedigylcol
1.00%
Sulphonated polymer
5.00%
[0094] Powder 2-1.3 grams
[0000]
Sodium percarbonate
100%
[0095] Gel composition—2.5 grams
[0000]
Glycerin
47.0%
Gelatin
3%
TAED
49.7%
Lupasol ® FG (PEI)
0.2%
Dye
0.1%
[0096] Total PEI content: 5 mg per unit dose.
[0097] Example compositions 1 and 2 were both tested according to the glass corrosion test methodology as set out in WO 2010/020765, pages 14 16. Both gave results at least equivalent to the results for Example 3 on Table 5a and 5b of WO 2010/020765, which is a solid formulation. The results for the compositions of the present invention were consistent and reliable when the compositions were produced on an industrial scale.
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The present invention relates to an improved detergent composition for use in the protection of non-metallic inorganic materials such as glassware in automatic ware washing machines.
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[0001] The present application claims the benefit of priority of pending provisional patent application Ser. No. 61/816,182, filed on Apr. 26, 2013, entitled “Novelty Currency”.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates generally to a novelty currency device and, more particularly, the invention relates to a novelty currency device taking advantage of two commonly used phrases, both associated with the concept of worthlessness, to drive home a message that stands in stark contrast to the cozy association of bribe and convenience endemic and implicit in disposable plastic promotional items.
[0004] 2. Description of the Prior Art
[0005] Traditional marketing giveaways function on a simple utility principle. The more useful device a promoter can emblazon with their client's identifying logo and address information, the more likely targeted customers are to incorporate it into their daily lives. This type of placement can be expensive to attain in many customers' lives. Customers are, for the most part, conditioned to hoard many such promotional gimmicks, usually only developing sustained emotional attachments to those that provide a significant utility. A classic example of this set is the pen. Pens inscribed with business contact information are the next logical leap after the invention of the business card. They provide not just a contact reference, but also a much-used business functionality that promotes, in the user, the desire to retain possession of the object itself, for completely tangential purposes. From here, the menagerie of promotional ephemera has expanded to its currently bloated state, with all manner of injection-molded plastic items of questionable functionality distributed in an attempt to secure valuable real-estate in the user's home and mind for business promotion purposes.
SUMMARY
[0006] The present invention is a novelty currency device for promoting the concept of worthlessness. The novelty currency device comprises a piece of currency and an alteration impression for altering the currency. The alteration impression provides an implied message of a reduced inherent value.
[0007] In addition, the present invention includes a method for promoting the concept of worthlessness. The method comprises providing a piece of currency, altering the currency with an alteration impression, and providing an implied message of a reduced inherent value.
[0008] The present invention further includes a novelty currency device for promoting the concept of worthlessness. The novelty currency device comprises a penny having a red color and a nickel having a aperture. The penny and nickel provide an implied message of a reduced inherent value.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a perspective view illustrating a novelty currency device, constructed in accordance with the present invention, with the novelty currency device being a red cent; and
[0010] FIG. 2 is a perspective view illustrating the novelty currency device, constructed in accordance with the present invention, with the novelty currency device being a plugged nickel.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0011] As illustrated in FIGS. 1 and 2 , the present invention is a novelty currency device, indicated generally at 10 , taking advantage of two commonly used phrases, both associated with the concept of worthlessness, to drive home a message that stands in stark contrast to the cozy association of bribe and convenience endemic and implicit in disposable plastic promotional items.
[0012] The novelty currency device 10 of the present invention consists of six cents worth of base materials. One piece consists of a regular American penny 12 , which has been covered over with a bright red enamel paint, and can be further decorated with a stenciled logo or campaign-specific message. The other element is a regular American nickel 14 , through which a round hole 16 has been bored. A small, circular plug 18 of rubber is inserted to fill the aperture 16 , restoring the smooth face on the front and back of the coin 14 . Together, the two pieces 12 , 14 of the novelty currency device 10 can be easily affixed to the front of any marketing or campaigning literature with a simple, removable gum adhesive, making them ideal for direct mail campaigns or decoration on the front of distributable brochures, hand bills and fliers.
[0013] Materials adorned with the novelty currency device 10 of the present invention contains a brief missive on the history and popularity of the two phrases that inspired the creation of these models. This discussion provides a wonderful starting point from which to segue into a discussion of the importance of value and the worthlessness of one's competing products or candidates. This type of negative campaigning has proved effective in marketing spheres as disparate as political campaigning and financial services sales. The novelty currency device 10 provides a wonderful physical reinforcement of the concept, offering a great pair of objects that end users can easily remove from any marketing material and carry with them in the pocket or purse to further spread the message to other users.
[0014] Using the novelty currency device 10 of the present invention is remarkably simple. Once the two items have been constructed, they can be distributed as needed, either by post or handed out in person. Regardless of the distribution method chosen, it's important to provide a concise explanation of what they are and what they represent. In this manner, the public can be effectively educated as to the true value represented by the candidate, product or service being promoted. The relatively low cost of the materials involved in constructing the novelty currency device ensures that many hundreds or thousands of sets can be cheaply and easily given away, at very little cost to the promoter engaging in that specific marketing campaign. The customizable face of the currency ensures that the items remain tied into the campaign in question, even when removed from any supporting documentation or expository display cards.
[0015] As both of the elements in the novelty currency device 10 of the present invention are constructed from real, legal tender, average users will find the sets incredibly hard to throw away. Nobody wants to be accused of wasting money, after all. The significant surface alterations to the coins also ensure that they cannot be easily spent, and the upshot of these paired restrictions is that most users who receive a free currency set will hold on to it, allowing it to continue building its helpful psychological associations in their minds long after the time when whatever handbill was distributed with them has been disposed.
[0016] The novelty currency device 10 of the present invention offers significant advantages over more traditional, disposable forms of advertising aimed and conveying the concept of true, value. The low cost of production ensures that wide-reaching campaigns targeting tens or hundreds of thousands of voters or potential customers are relatively cheap to execute. The inherent value of the objects being distributed, on the other hand, provides a virtual guarantee that any potential adherent to the cause will keep the items with them and possibly even push the message further, indoctrinating his or her friends and family into whatever concepts that the coins represent.
[0017] The foregoing exemplary descriptions and the illustrative preferred embodiments of the present invention have been explained in the drawings and described in detail, with varying modifications and alternative embodiments being taught. While the invention has been so shown, described and illustrated, it should be understood by those skilled in the art that equivalent changes in form and detail may be made therein without departing from the true spirit and scope of the invention, and that the scope of the present invention is to be limited only to the claims except as precluded by the prior art. Moreover, the invention as disclosed herein may be suitably practiced in the absence of the specific elements which are disclosed herein.
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A novelty currency device for promoting the concept of worthlessness is provided. The novelty currency device comprises a piece of currency and an alteration impression for altering the currency. The alteration impression provides an implied message of a reduced inherent value.
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REFERENCES TO RELATED APPLICATIONS
This application relies for priority on U.S. provisional application No. 60/230,618 filed on Sep. 5, 2000 and entitled “System and Method for Fabrication Components of Precise Optical Path Length”, P. Chen et al, and a continuation-in-part of U.S. application Ser. No. 09/898,469 filed Jul. 6, 2001, still pending by A. Eyal et al for “Interleaver Filters Employing Non-Birefringent Elements”.
FIELD OF THE INVENTION
This invention relates to methods and systems for the fabrication of optical elements of precise length and more particularly to fabrication of elements having optical path lengths exact enough to be used in applications for optical communications which use optical interferometry.
BACKGROUND OF THE INVENTION
There have long been needs for exactness in mechanical and optical devices and systems, and these needs have heretofore been met by a variety of techniques, from mechanical to optical. Examples of the latter are found in a 1922 publication of the Department of Commerce, entitled “Interference Methods for Standardizing and Testing Precision Gage Blocks” by C. G. Peters and H. S. Boyd, which describes light wave interference methods which are not subject to the “appreciable errors” found with “micrometer microscopes” and “contact instruments”. The authors describe optical interference approaches imparting about an order of magnitude improvement, e.g. from 0.25 to 0.025 microns. While directed to the calibration of gage blocks, this article nonetheless evidences what even today must be acknowledged as an ingenious optical approach to ascertaining the dimensions, flatness and parallelism of gage surfaces.
In modern telecommunication systems, however, dimensional measurements are embedded in a number of other factors which arise from the way in which optical elements are used. In telecommunications systems using device wavelength division multiplexing (DWDM), for example, polarization interferometry that requires precise differential delays between different beams is used in generating a required filter function. Interleavers employing these relationships are described in U.S. application Ser. No. 09/898,469 referenced above to provide athermal operation within individual stages of multi-stage multiplexers and demultiplexers.
The optical path length of an optical component through which light traverses is dependent not only on distance but also on intrinsic properties, such as the index of refraction, of the components. Modern optical systems must meet such demanding specifications that optical path length has become an important consideration. The fabrication of interleaving optical filters for DWDM using athermal delay line interferometers requires strict control of the optical path lengths of the glass elements. This control is necessary to meet the tight tolerances on absolute channel frequencies for DWDM applications. Traditional physical path length measurements such as mechanical or non-contact thickness probes with sub-micron accuracies are thus not adequate because the optical path length depends on both physical thickness and the absolute index of refraction of the medium. Also, for individual glass melts the index of refraction of typical optical glasses varies by 10 −5 to 10 −4 from a nominal or target value despite best production methods. This variation introduces substantial uncertainty in optical path length even if the physical thickness of the glass is known exactly. A particular additional requirement is that the optical path length of any “glass window” must be accurately measured at a chosen wavelength of operation (e.g., 1550 nm) to account for material dispersion.
SUMMARY OF THE INVENTION
Methods and systems for fabricating optical elements such as microoptic elements used in introducing differential delays in DWDM interleavers, use a number of different measurements of frequency periodicity at successive evolutionary processing steps leading to final sizing. The method and system provide precise frequency periodicities, with optical elements being so interrelated as to be acceptably athermal at a chosen frequency. The optical elements thus form the basis for a desired transmission spectrum for a DWDM interleaver. Frequency periodicity is synthesized by measuring output amplitudes derived from differential delays of a test beam at a plurality of incrementally varying wavelengths in the wavelength range of interest, using polarization interferometers to introduce a filter function.
To fabricate to interleaver precision, the optical frequency response of the interleaver must be characterized to sub-GHz in terms of accuracy. The first step in the characterization process is to measure the temperature dependence of the glass, and then calculate to high accuracy the physical lengths needed for both athermal operation and desired frequency periodicity. A first optical element or window is then ground and polished to the desired frequency periodicity given by a first calculation. For example, consider the case of a 50 GHz interleaver with a 100 GHz free spectral range (FSR). The first window is fabricated from the higher index glass of a pair of glasses to be used and is polished to within about 0.04 GHz of the target value to ensure good temperature insensitivity of the final interleaver. This glass element is left in the optical frequency measurement system, and the second window is then ground, polished and repeatedly measured by placing into the second arm of the optical path length measurement system until the frequency periodicity of the combined two glass interleaver is 100.00+−0.03 GHz. A like process is utilized to fabricate time delay elements for other FSR's, such as 25 GHz to 200 GHz.
In accordance with the invention, the frequency periodicity is ascertained during different steps using the differential delays introduced between different optical elements or one optical element and air in the delay paths of a polarization interferometer. An input test beam is propagated through both delay paths, but varied incrementally in wavelength through a selected range of wavelengths. This results in derivation of a sinusoidal variation from which peak to peak spacings determinative of frequency period can be calculated so that optical path length correction can be computed to a degree of accuracy dependent on the state of dimensional refinement of the element. By starting with precursor elements large enough in transverse area for multiple microoptic elements, and using the given oversize in thickness in the precursors, removal of thickness to final dimension can suffice for all microoptic elements at the same time.
To achieve these tolerances, the measurement system described herein meets the extremely high accuracy standards implicitly required for the measurement of optical path length. During the final polishing process of the glass window blanks, the optical path length is periodically measured until the target value is achieved. This measurement technique enables conventional polishing techniques to achieve the desired thicknesses.
Precise optical path length measurements have been achieved, accurate to better than 10 ppm. That is, a glass element with a free spectral range of 100.000 GHz can be fabricated to have a period accurate to better than 1 MHz. The parameter that is directly measured is the optical frequency response of the interleaver in about the 1500 to 1600 nm wavelength range but the determinative result is the establishment of optical path length.
A measurement system in accordance with the invention employs a tunable laser, controlled by a data processor to scan a selected wavelength range in equal, small increments, to generate wavelength varying test beams. The beams are directed through a differential delay system using polarization interferometry to generate a wavelength dependent output. This is received at a spectrum analyzer which stores the sinusoidally varying amplitude readings from the different wavelengths for analysis.
The data processor receives the data and employs a least squares fit program to analyze the sinusoidal variations and ultimately derives the length correction needed for an optical element. The optical measurement apparatus for introducing differential delays in microoptic elements, which area used in testing temperature dependence is in the form of a single stage interleaver. Measurement apparatus for large precursor elements incorporates stages which can be adjusted in two dimensional to position the optical element. Additionally, using illumination directed from a broadband light source through the optical element onto the spectrum analyzer, the tilt and tip orientation of the optical element can be optimized before differential delay readings are made. The laser beam power is advantageously monitored by a power meter coupled to provide measurement signals to the data processor for use in equalizing readings derived during scanning. Also a polarization scrambler is preferably employed in the beam path where polarization dependence in the interferometer may affect readings, by assuring that there is no dominant polarization.
BRIEF DESCRIPTION OF THE DRAWINGS
A better understanding of the invention may be made by reference to the following description, taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a block diagram of an optical measurement system in accordance with the invention that includes a top view of a polarization interferometer optic;
FIG. 2 is a side view of the optical layout of the polarization interferometer optical path length measurement system of FIG. 1;
FIG. 3 is a top view indicating the location of positioning elements for placement of glass elements into a polarization interferometer;
FIG. 4 is a process flow chart depicting steps in determining glass temperature characteristics to high accuracy;
FIG. 5 is a process flow chart depicting steps in fabricating glass elements to high accuracy in frequency optical path length;
FIGS. 6A and 6B are graphs presenting the temperature stability of the center frequency of fabricated using the process outlined in FIGS. 4 and 5;
FIG. 7 is a graph illustrating the center frequency temperature dependence achieved with two and three glass designs; and
FIG. 8 is a graph illustrating the temperature dependence of the response of an interleaver fabricated in accordance with the process depicted in FIGS. 4 and 5 .
DETAILED DESCRIPTION OF THE INVENTION
Extremely tight fabrication tolerances must be maintained between the differential optical paths of a system such as an advanced state of the art interleaver (e.g. Ser. No. 09/898,469 supra) to both provide athermal operation and to achieve the desired frequency periodicity. The differential optical path length between the two arms must be kept constant to a high level of precision (1 part in 10 4 ) to maintain a constant period of 100.00 or 200.00 GHz, for example. The approximate optical frequency is 193.000 THz, and the absolute frequency of each channel should be aligned to the ITU wavelength grid to better than 1 GHz. The deviation of the frequency period from the target value, for a typical 80 channel C band application, should be below 50 MHz. Practically, there is no glass material available with optical path length temperature dependence matched to the necessary level to that dependence exhibited by air. Individual glasses have a relatively large dependence of the optical path length on temperature. Therefore, a second glass material is necessary to compensate for the temperature dependence introduced by the first glass, and a third glass material can also be used for further improvement. Furthermore, it is advantageous to place glasses of substantially equal length in both arms. This eliminates the dependence of the interleaver's frequency response on ambient air conditions, which can be significant for 50 GHz or denser interleavers. The length of glass is selected to give the correct optical path length difference. The two glasses also should be matched in their optical path length temperature dependence. 50 and 100 GHz interleavers include glass elements cascaded from length L, such as 2L and 4L in a stage, where L is typically about 5 mm. The tolerances of L are on the submicron level, requiring precise thickness or optical path length control during the polishing process.
Some considerations based on the theory of the polarization interferometer are desirable to understand the degree of exactitude needed in optic components for optical interferometer systems. The transmission frequency response in terms of optical power of a single interleaver stage is given by:
T =sin 2 (φ), (1)
where the phase for an N glass interleaver is given by: φ = 2 π f c ( ( n 1 - n air ) L 1 - ( n 2 - n air ) L 2 - … - ( n N - n air ) L N ) . ( 2 )
The frequency dependence of the phase for an N glass interleaver is: ∂ φ ∂ f = 2 π c ( ( n 1 - n air ) L 1 - ( n 2 - n air ) L 2 - … - ( n N - n air ) L N ) + 2 π f c ( ∂ n 1 ∂ f L 1 - ∂ n 2 ∂ f L 2 - … - ∂ n N ∂ f L N ) ( 3 )
In the following, we will focus specifically a two glass interleaver design; however, similar analysis applies for the case of three or more glass types. For this case of two glasses the temperature dependence of the phase is: ∂ φ ∂ T = 2 π c ( ( n 1 - n air ) ∂ L 1 ∂ T - ( n 2 - n air ) ∂ L 2 ∂ T ) + 2 π f c ( ∂ n 1 ∂ T L 1 - ∂ n 2 ∂ T L 2 ) ( 4 )
The frequency periodicity of the total interleaver is: Δ f = c ( ( n 1 - n air ) L 1 - ( n 2 - n air ) L 2 ) + f ( ∂ n 1 ∂ f L 1 - ∂ n 2 ∂ f L 2 ) ( 5 )
For example, for a 50 GHz interleaver, Δf=100.00 GHz, and for a 100 GHz interleaver, Δf=200.00 GHz. The frequency periodicity of individual glasses 1 and 2 under the condition of temperature compensation is: Δ f 1 = Δ f ( 1 - ∂ f 1 ∂ T ∂ f 2 ∂ T ) ( 6 ) Δ f 2 = Δ f ( ∂ f 2 ∂ T ∂ f 1 ∂ T - 1 ) ( 7 )
By choosing L 1 =L 2 , the temperature dependence of air factors out of the interleaver frequency response. If this condition were not met, a 6 mm element of air would contribute a frequency shift of approximately 3 GHz/10° C. This effect also depends on whether the interleaver operates under constant pressure or constant volume conditions after it is sealed and packaged. Therefore, for highly stable telecom applications, insensitivity to inner atmosphere (e.g., air pressure or temperature) is necessary.
Measurement System
A functional diagram of a measurement system used to characterize the glass elements is illustrated in FIG. 1 . The measurement system comprises a number of operative elements: a computer 10 with frequency period analysis software, a tunable laser 12 operated in a wavelength scanning mode by the computer 10 using scanning control algorithms, a polarization scrambler 14 , an optical measurement bench 16 , a power meter 18 to which the laser beam can be directed after the bench 16 at a junction 19 comprising a switch, fiber or splitter, and an optical spectrum analyzer 20 . the power meter 18 and the spectrum analyzer 20 provide signals to the computer 10 for use in normalizing the readings. The computer 10 is interfaced to the tunable laser 12 using a standard bus such as GPIB, serial, or parallel, and the optical measurement bench 16 provides communication between the tunable laser 12 , optical power meter 18 and optical spectrum analyzer 20 , through switches or optical fibers. A separate, broadband light source 22 provides light into the laser beam path via a junction 24 which may comprise a beam combiner on an optical switch.
The optical measurement bench 16 consists of a series of polarization beam splitters, ½ waveplates and polarizers, as seen in both FIGS. 1 and 2, corresponding in substantial part to the basic elements of the interleaver. Beam displacers, fabricated from birefringent crystals, can be used for both the polarization beam splitters and polarizers. In general terms, an incoming beam from the laser 12 is split in the optical measurement bench 16 into two polarized beams which are laterally displaced from one another but exit the crystal along parallel paths. One outgoing beam from the displacer is e polarized, the other is o polarized, where the orientations of the e and o polarizations are dictated by the crystal orientation of the beam displacer. The parallel beams are directed through differential delay paths which are used in the testing of different glasses or relationships before the beams are recombined for the remainder of the measurement.
Several optical layouts achieve the desired optical measurement response. This example (FIGS. 1 and 2) utilizes an input collimator 30 , a polarizer 32 (Coming Polarcor™ for example) oriented at 45° to the horizontal, a first horizontal beam displacer 34 , and a true zero order ½ waveplate 35 to rotate the polarization of the displaced e and o beams by 90° before one or more glass elements to be measured for optical path length. The elements, called windows or pucks when in multi-element size, or microoptics elements if they are sized for use in an interleaver, may be used singly or in combinations in the measurement bench 16 . in this example, two windows, 36 , 37 (designated Glasses 1 and 2 ) are depicted as in positions they occupy (individually or concurrently) intercepting the beam paths in the delay segments. An optional window 38 , shown in dotted lines in FIGS. 1 and 2, is Glass 3 which may be measured also if a three glass stage is to be fabricated. A second horizontal beam displacer 40 follows the windows 36 , 37 to recombine the two beams, an output polarizer 42 oriented at −45° to the horizontal, and an output collimator 44 . All optics are antireflection coated in the 1500 to 1600 nm window, and the zero order waveplate is here designed for 1550 nm operation. Note that this optical layout closely resembles a single stage of the actual microoptic interleaver described in U.S. patent application Ser. No. 09/898,494 by Eyal et al., but on a larger scale to allow the precursor window blanks to be tested before dicing into microoptic windows.
The input optical beam is here, however, not dependent on the state of polarization of the laser 12 output. The polarization scrambler 14 rotates the input beam polarization repeatedly during the duration in which each beam of different wavelength is transmitted. The power meter 18 samples the beam amplitude and is operated separately from the optical spectrum analyzer 20 after recombination, so that the computer 10 can normalize the readings from the spectrum analyzer 20 .
This arrangement provides a relatively simple yet precise means of sampling the wavelength scanning test beams. If the laser output is uniformly polarized, the components may be oriented suitably to that reference. If the beam has an arbitrary state of polarization, the input beam may be split into upper and lower pairs of orthogonal polarizations, to provide a polarization independent output as in the Eyal et al application.
The input horizontal beam displacer 34 separates the input beams into e and o polarized beams, horizontally spaced by about 0.7 mm. The e and o beams may pass through one or more different glass elements 36 , 37 , etc., depending upon the measurement to be performed. Upon propagating through the glass elements, 36 , 37 , etc., the two beams acquire a relative phase shift between one another, because of the different indices of refraction of the glasses, and next enter a ½ waveplate 35 oriented at 45° to convert the o to e and the e to o polarizations. The two beams are then recombined into a single output beam by the output horizontal beam displacer 40 . The waveplate ensures that the optical path lengths traveled by the two beams (left and right) through the displacers 34 , 40 are equal. The lengths of the input and output beam displacers 34 , 40 are also precisely matched to ensure that the split beams are recombined into a single spot, and to precisely match the net distance each beam travels within the two displacers. Any residual path-length mismatch is precisely measured and mathematically corrected for in the data processing performed during the measurements.
This optical system is connected to the lightwave measurement system (FIG. 1) which scans and processes the wavelength response of the polarization interferometer. An Agilent 81641 tunable laser mainframe 12 provides a test beam to the interferometer input, and the interferometer output is measured by the single channel optical power meter 18 to record the transmitted optical power in transmission on the computer 10 . The laser 12 is scanned from 1520 to 1570 nm with a 0.01 nm step size for a total of 5000 points. The signals measured by the lightwave measurement system constitute a sinusoidal amplitude response varying with optical frequency. The data is least-squares fit by the computer 10 and period analysis software to a sinusoid, the two fit parameters being the optical frequency period and the phase to determine the frequency period to a few parts in 10,000. A 50 GHz interleaver, for example, requires an optical frequency period of 100.00 GHz. The control of the laser wavelength scanning, data acquisition, and least-squares curve fitting is performed by commercial software, for example, LabVIEW from National Instruments, Inc.
The optical path length of the glass windows 36 , 37 , 38 depends partly on the angle of incidence of the beams with respect to the windows. Normal incidence corresponds to the shortest optical path length. To ensure that the one or more glass windows are positioned exactly normal to the optical beams (within a few arcmins), an Agilent 71452B optical spectrum analyzer functioning with the broadband light source 22 in the communication link may be used to monitor the spectral response of the polarization interferometer in real time as the tilt and tip of glass windows 36 , 37 are adjusted.
Upon inserting only the first piece of glass, e.g. 36 , the tilt and tip are to be adjusted until the frequency period of the interleaver is minimized, which minimizes the optical path length in the glass. FIG. 3 illustrates the apparatus used to achieve orientational adjustment of the glass windows during the measurement process, with commercial micropositioning tables 47 , 48 being employed that are adjustable in two angular directions, specifically in tilt and tip. Such micropositioning tables are available from Newport Corp. and other optical equipment suppliers. For the second piece of glass, the tilt and tip are also adjusted until the frequency period of the interleaver is maximized or minimized, depending on the glass type, index of refraction and its length. Additional pieces of glass are to be inserted using a similar procedure. Those angles ( 1 b , 2 b , 3 b ) which are to be maintained close to normal incidence are indicated as small squares in FIGS. 1 and 2. If the angles are not 90 degrees, then the optical path length measurement is incorrect. The beam displacers and waveplates are epoxied in place to maintain mechanical stability during the measurements, and the input and output collimators are welded to the optical bench. The polarization scrambler 14 is typically installed in-line with the tunable laser output to ensure that the state of polarization is scrambled or depolarized at the input to the measurement system 16 .
Characterization of Temperature Dependence of Glasses
FIG. 4 is a flow chart outlining the steps required to characterize glass delay line elements to the level needed to temperature compensate interleavers while also achieving the precise frequency periodicity. The flow chart of FIG. 5 depicts processing steps used after this characterization has been completed.
This example applies to a two glass design, but the method can be readily extended to a three or more glass design using Equations 2-3 above. These delay line elements are to be processed as large glass “pucks” or plane parallel windows, which are subsequently diced into microoptic elements. The first step is to select suitable glasses which compensate for one another's temperature dependence. This is based initially on the therrno-optic and thermal expansion contributions to the temperature dependence, as determined from the vendor specifications. These published parameters, which are not adequately precise for present purposes are input into Equations 6 and 7 to provide the target frequency periodicity of each glass. The glass pucks are then ground and polished to be at some predetermined frequency above the target frequency. Typically, these frequencies are chosen to correspond to pucks each 100 ums thicker than the predicted target thicknesses (each about 9 mm thick). A microoptic element from each puck is then diced and used to build, in effect a one stage interleaver, from which the temperature dependence of the center frequency is measured. These measurements enable the residual temperature dependence of the pair to be calculated, from which the errors in the published specifications can be calculated and corrected for. Each glass melt has slightly different index of refraction and thermal characteristics, so that in general this thermal characterization process should be repeated for each glass melt, and used in calculating the residual temperature dependence.
Method to Fabricate Glass Elements of Precise Optical Path Length
FIG. 5 illustrates the method by which glass elements are fabricated to a precise optical path length, after the measurements have been made which characterize the temperature dependence of the glasses. The input signal to the optical measurement bench 16 is generated by the tunable laser 12 which scans the wavelength region of interest (C or L band). The polished window blanks e.g. 36 , 37 are first ground and polished to a thickness slightly over the target value. Conventional thickness measurement techniques are used up to this point. Next, the optical thicknesses of the parts are determined using the measurement system described herein and the following sequence. First, one oversize glass element e.g. 36 , is placed in the optical measurement bench 16 and aligned. Next, the amount of material to be removed is calculated, and further material is removed. This step is typically a final mechanical polishing step which can be carried out commercially to a high degree of precision once the absolute value of material to be removed is known. Alternatively, processes such as reactive ion etching or chemical etching can be utilized to remove the small amount of material during this final process step. Magneto-rheological polishing is an alternate technique which allows precise figuring of both the flatness and optical thickness of individual polished windows. When the first glass element 36 has been polished to the correct optical path length, the second glass element is inserted, and it is polished until the second target frequency periodicity is achieved. This process may be continued if more than two glass elements are used in the design. Note that the polishing may be simultaneously conducted on a large number of relatively large glass “pucks” of identical thickness. This provides the advantage of batch processing because thousands of microoptic elements are produced during each production run.
The windows are ground on a double sided ring lap using aluminum oxide slurry, and subsequently are polished on a similar double sided ring lap using cerium oxide slurry. Both these double sided machines optimally utilize pitch polishing rather than pad polishing. Alternately, a conventional double sided polishing machine using epolyurethane pads, for example, may be suitable for the lapping and polishing operations. In either approach, the double sided polishing has the inherent advantage that the flatness errors of both surfaces are in general complementary. As a consequence, the transmitted wavefront distortion of these plane parallel windows is inherently low, which is important to maintain consistent optical path length across the entire window. These windows are fabricated to provide a transmitted wavefront distortion of better than λ/3 to λ/10 (where λ=633 nm) across the 2 inch diameter substrate.
Processing of large diameter parts provides several advantages; namely, excellent surface flatness, transmitted wavefront distortion, parallelism of polished surfaces, and batch processing. The optical path length or physical thickness of the parts can be measured during the polishing stage to determine how much material should be removed. The removal rates are a well characterized part of the process (e.g., um per hour). This ensures that the glass elements are fabricated to the correct thickness to guarantee temperature insensitivity and to achieve the correct interleaver frequency response.
After these frequency targets are achieved, the glass is diced into a large number of identical microoptic windows. Upon dicing these large windows into microoptic delay line elements of, for example, 2.6×2.6 mm cross section, the residual power contribution to the flatness, which scales as the square of the diameter of the part, results in a transmitted wavefront distortion of less than λ/300 across the individual parts. Note, however, that this level of wavefront distortion is in practice not measureable.
In practice, this procedure gives extremely good temperature stability of the center wavelength. FIGS. 6A and 6B illustrate some typical dependencies of the center frequency with temperature, for 50.000 and 25.000 GHz interleavers, respectively. Note that the frequency drift varies approximately quadratically with center frequency within the passband. The linear dependence has been effectively nulled. The total shift with temperature is typically less than 2 GHz over the −5 to 65° C. operating temperature range for this group of interleavers.
By adding a third glass element, additional design flexibility is obtained. The residual quadratic temperature dependence can then be nulled, leaving only a cubic dependence. FIG. 7 illustrates the residual temperature dependence for a two and three glass design. FIG. 8 depicts the resulting transmission spectrum of an interleaver using the process described herein to fabricate a 50 GHz interleaver of precise period and low center frequency drift with temperature. The measured transmissions at −5,+5,+25,+45, and +65 degrees C are overlaid for comparison.
Systems and methods in accordance with the invention enable noncontact measurement of optical path length in terms of the thickness of optical windows to an accuracy of 100 nanometers. Further it is amenable to use in high production processes since large precursor blanks can be dimensioned together to provide a multiplicity of individual microoptic elements. While particularly suited for meeting the critical requirements of optical communication system, such as interleavers, these systems and methods are applicable wherever comparable requirements exist.
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Optical components, particularly microoptic glass components used in synthesizing birefringence in filter systems based on polarization interferometer techniques, are fabricated using systems and methods which provide accurate frequency periodicity measurements. These measurements are derived from differential delays induced by in-process glass elements between beam components in a polarization interferometer unit and from progressive wavelength scanning across a wavelength band of interest. The consequent sinusoidal output variation has peak to peak spacings which are measured to provide frequency periodicity values from which precise length corrections for the optical elements can be calculated.
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This is a continuation of copending application Ser. No. 07/488,548 filed on Mar. 5, 1990, now abandoned.
TECHNICAL FIELD
The present invention relates to electrical transducers and, in particular, to a resonant electrical system for driving a segmented transducer.
BACKGROUND OF THE INVENTION
The output capability of electrical transducers can be modified and expanded by selectively stimulating joined transducer segments. For example, piezoelectric actuators, an illustrative class of electrical transducers, can be constructed of stacked segments to provide a three-dimensional mechanical output. By combining cyclically alternating traction strokes of two or more piezoelectric actuators, "walking" motion can be produced.
At the start of tractional contact in conventional resonant actuators, such as resonant ultrasonic traveling wave motors, relative velocity between the actuator and a movable object results in initial sliding until firm contact is established. At the end of the traction portion of the cycle, sliding occurs again in preparation for the lift-off and retrace portions of the cycle. In such a system efficiency of electromechanical power conversion is reduced by sliding friction, particularly on retrace when the relative velocity is greatest. The electromechanical conversion efficiency of an actuating device with a conventional resonant drive is generally less than about 40%, with most of the loss caused by sliding friction. Rotors of resonant traveling wave piezoelectric motors are known to become uncomfortably hot to the touch after a few minutes of operation. Furthermore, resonant actuators that use circular or elliptical traction paths impart a time-varying normal force and a time-varying tangential (traction) force to the positioned object or rotor. As a result, linear motion is jerky and motors have torque ripple.
The speed of action of resonant actuators may be adjusted by altering the magnitude of the voltage swings or the mechanical strokes. However, resonant devices operate most efficiently at full power and full speed. Speed reduction by reducing amplitude also reduces efficiency because the energy allocated to sliding friction becomes an increasing fraction of the total available energy. As the size of the circular or elliptical motion is decreased, rubbing during retrace is exacerbated. The lower limit of speed is determined by the resonant amplitude at which traction cycling becomes intermittent or ceases altogether. Holding a controlled stationary position and applying a static traction force are beyond the operating scope of a resonant actuator.
Resonantly excited piezoelectric actuators of the prior art employ the thickness or extension piezoelectric deformation mode, wherein ferroelectric polarization is parallel to the applied electric field. Such polarization is degraded or even reversed if the applied potential causes an electric field anti-parallel to the direction of polarization. Resonance requires that large voltage swings be substantially symmetric about a floating median potential value. Elevation of the floating median value by at least half the peak-to-peak voltage swing above electrical ground avoids depolarization. This requires that the electrical circuitry operate at a relatively high voltage above ground, resulting in a safety hazard in large actuators.
Slowly varying direct current electrical sources, such as programmable DC power supplies, for example, have been used to control piezoelectric positioners. These power sources emulate class A amplifiers but have a restricted frequency response. All the reactive capacitive current flows through the amplifier output devices. A class A amplifier dissipates all of the available power internally under null excitation. The variable DC voltage is essentially free of superimposed high frequency ripple, and it provides smooth control and piezoelectric positioning at slow speeds (including zero speed) with relatively good positioning accuracy. At modest frequencies and voltages, programmable DC power supplies operate piezoelectric actuators as smooth walkers without losses from sliding friction. However, high efficiency is beyond the capability of a programmable DC power supply emulating a class A or class B amplifier. Operation becomes more difficult and less efficient above a few traction cycles per second or with voltages above about 200 volts. Furthermore, none of the known class A or class B linear amplifiers remain stable when driving an entirely capacitive load. Therefore, they ar not applicable to electromechanically efficient piezoelectric walking actuators except at the lowest portion of the amplifier's frequency band.
An electronic drive described in U.S. Pat. No. 4,628,275 issued to Skipper, et al. emulates a class A amplifier. The amplifier provides the high bipolar voltage swings necessary to operate piezoelectric shear actuators. However, the ultrasonic charge transfer cycles of the amplifier, even when holding a steady voltage, accelerate the rate of wear and fatigue in all mechanisms connecting the actuator to positioned objects. Furthermore, the amplifier requires high voltage DC power supplies, large and heavy transformers, and very fast switching devices to achieve modest electrical efficiencies. The use of AC-to-DC power converters and the presence of large reactive currents in output switching devices preclude efficiencies above about 80%.
Piezoelectric actuators capable of smooth walking are inherently well suited to operation in a vacuum, such as in orbiting space stations, because lubrication is not required. The high electromechanical efficiency of piezoelectric actuators, which exceeds 98% neglecting internal electrical losses, also precludes excessive heating during operation, thus eliminating the need for ancillary cooling that reduces overall system efficiency. Furthermore, piezoelectric actuators require no additional energy from the power source to maintain a stationary force.
Operation in a vacuum imposes similar thermal management requirements on the drive electronics. The need for heat removal decreases dramatically with increasing efficiency. Internal heat generation by an ideal electrical power source is negligible when piezoelectric actuators apply a stationary force or operate at low velocities. Ideally, the energy supplied by the drive system should equal the energy converted to useful mechanical work by the actuators. Thus, there is a need for a highly efficient electrical system to supply appropriate resonant waveforms for nonsinusoidal transducer output such as smooth walking motion by piezoelectric actuators.
SUMMARY OF THE INVENTION
Electromechanical resonance in a conventional transducer produces a sinusoidal output that is most easily described by sine and cosine waves that generate elliptical or circular mechanical output. In contrast, the present invention comprises an electrical system for driving a segmented transducer to produce arbitrary output waveforms. Each segment of the transducer is connected to an electrical controller by a separate electrical loop. The electrical controller provides a separate resonant electrical signal on each loop to stimulate each individual segment of the transducer. Each segment reacts to the resonant electrical stimulation on its loop. However, because the segments are coupled to form the transducer, the overall output of the transducer, typically in the form of force or motion, comprises the vector sum (neglecting coupling effects) of the output reactions of the individual segments of the transducer. Thus, the system of the present invention provides the capability of generating a nonsinusoidal transducer output at high efficiency by the process of mechanically summing a plurality of individual segment reactions produced by a corresponding plurality of resonant electrical stimulations.
The system of the present invention can generate a wide variety of output waveforms by the selection of appropriate electrical loop frequencies and Fourier coefficient amplitudes. By way of example and not limitation, the present system is applicable to piezoelectric actuators, electromagnetic actuators, magnetostrictive actuators, and thermal expansion devices. Also, periodic disturbances in many types of machinery and in delicate instruments, such as optical benches, are characteristically nonsinusoidal and can be reduced or cancelled by application of the principles of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention and for further advantages thereof, the following Description of the Preferred Embodiment makes reference to the accompanying Drawings, in which:
FIG. 1 is a perspective view of a piezoelectric dimorph;
FIG. 2 is a perspective view of a piezoelectric actuator comprising a plurality of stacked dimorphs;
FIG. 3 is a perspective view of adjacent actuators positioned for walking;
FIG. 4 is a schematic diagram of an electrical drive system of the present invention;
FIG. 5 is a plot of an ideal mechanical waveform for the tangential action of a two-axis, constant velocity, smooth walking piezoelectric actuator;
FIG. 6 is a plot of the mechanical sum of six actuator segments approximating the ideal waveform of FIG. 5;
FIG. 7 is a plot of the first four individual waveforms of the six actuator segments that are summed to produce the plot of FIG. 6;
FIG. 8 is a plot of an ideal mechanical waveform for the perpendicular action of a two-axis, smooth walking piezoelectric actuator;
FIG. 9 is a plot of the mechanical sum of six actuator segments approximating the ideal waveform of FIG. 8;
FIG. 10 is a plot of 30% piezoelectric segment hysteresis;
FIG. 11 is a quarter-cycle plot showing the hysteresis lag of a piezoelectric segment;
FIG. 12 is a quarter-cycle plot showing the hysteresis lag of the perpendicular action of a piezoelectric actuator; and
FIG. 13 is a quarter cycle plot showing the perpendicular action when the hysteresis time delay illustrated in FIG. 11 is subtracted from the activation time of each segment of the actuator.
DETAILED DESCRIPTION OF THE INVENTION
The present invention comprises a system for driving electrical transducers, such as piezoelectric actuators, to produce nonsinusoidal transducer output. Although the following description concentrates on piezoelectric actuators as a representative class of transducers, the present invention is suitable for driving any type of segmented electrical transducer.
For a clear understanding of the present invention, FIGS. 1-3 provide an introduction to layered piezoelectric actuators. FIG. 1 shows a piezoelectric cell 2, called a "dimorph." Dimorph 2 comprises piezoelectric layers 4a and 4b, a central electrode film 6 for connection by lead 12 to an electronic drive 14, and electrode films 8a and 8b for connection to ground leads 10. Piezoelectric layers 4a and 4b are polarized in directions indicated by arrows P a and P b , respectively. The term "dimorph," therefore, means a piezoelectric cell having two complementary layers of piezoelectric shear material with grounded outer electrodes.
When drive 14 applies a negative electric potential to electrode 6, an electric field is established in the direction indicated by arrow E b in layer 4b. Holding electrode 8b stationary in space, the combination of field E b and polarization P b causes shear such that electrode 6 translates parallel to electrode 8b in direction 15. Because the piezoelectric polarization direction P a in layer 4a is anti-parallel to the polarization direction P b in layer 4b, the negative potential applied to electrode 6 establishes an electric field E a anti-parallel to the field E b in layer 4b. This combination of polarization and electric field causes layer 4a to shear such that electrode 8a translates relative to electrode 6 in direction 15.
The translations of the piezoelectric layers have the same magnitude and direction when the two layers have congruent geometries and equivalent piezoelectric properties. The two layers are connected in electrical parallel and in mechanical series. Thus, electrode 8a translates relative to electrode 8b by the vector sum of the translations of the individual layers. The application of a positive potential to electrode 6 reverses the directions of the illustrated electric fields, thereby reversing the direction of the shear translations. Electrodes 8a and 8b are maintained at electrical ground, and electrode 6 is centrally located between the ground electrodes to maintain symmetry of current loops. Electrode 6 is driven most effectively with a bipolar signal having equal positive and negative peak potentials. Bipolar drive does not depolarize the layers because the electric fields are perpendicular to the directions of polarization. Bipolar drive doubles the shear piezoelectric translation compared to the monopolar drive used for conventional piezoelectric actuators operated in the thickness or extension modes. In addition, the piezoelectric shear deformation of dimorph 2 per unit electric field intensity is generally greater compared with other piezoelectric polarization modes.
Dimorph 2 may be used as an electromechanical positioner and transducer of force. Predetermined alternate dispositions of electrodes and polarization directions result in dimorphs that translate in one of three desired orthogonal directions. One, two, or three shear deformation dimorphs may be combined into an actuator to provide one, two, or three positioning axes, respectively. A shear actuator can be made by coupling dimorphs together in any order and number and with any desired combination of orthogonal motional directions. Grounded outer electrodes allow electrical and mechanical connection of dimorphs to each other and to other electrically conducting structural members without regard to the electrical state of the bonds.
Ancillary electrical insulators are not needed when stacking dimorphs to form actuators. Elimination of insulators improves electromechanical performance by eliminating unnecessary elastic insulator compliance and by minimizing the distance from a structural attachment to the point of actuator-applied force. In addition, all grounded electrodes may be interconnected and attached to ground at a single location.
FIG. 2 shows a piezoelectric actuator comprising a base 22, a plurality of stacked dimorphs such as dimorph 2, and a protective "tractor" or "foot" 24. Each of the plurality of dimorphs is connected to electronic drive 14 with a connection such as lead 12 connecting dimorph 2. Ground leads connected to electrodes between dimorphs are omitted for clarity. The dimorphs are coupled together and affixed to structural supporting base 22. Tractor 24 is affixed to the electrically positionable actuator end remote from base 22. The position of tractor 24 is the vector sum of dimorph translations (neglecting coupling effects), as indicated by directional arrows 16, 18, and 20.
The commonly used ferroelectric form of piezoelectric material comprises a collection of electric domains, each of which aligns at a different speed in response to a applied steady electric potential. For example, when a steady voltage step is applied to the actuator, those domains that align quickly achieve the majority of mechanical stroke in a relatively short time. Regardless of the steadiness of the applied potential after the step change, the mechanical stroke approaches its full extent asymptotically as the slower domains align with the electric field, which may be called drift. It is desirable in many applications of piezoelectric actuators to provide a mechanical stroke that faithfully follows the magnitude of the applied electric potential. One known method is the use of a position detector to close a control (feedback) loop with the actuator and its electrical drive. The advantage of loop control positioning is the elimination of positioning errors due to drift.
For reasons of clarity but not limitation, the following description includes piezoelectric actuators having only two orthogonal tractor motions, normal (i.e., perpendicular) and tangential. Extrapolations to three orthogonal motions are easily derived by one skilled in the art. Tractor 24 positions a movable object by contact friction, or traction. The movable object may be an actuator rod or a motor shaft, for example. At least one surface of the movable object proximate the tractor is a traction surface called a "tractee." Dimorphs that move tractor 24 in direction 16, tangential to the tractee, are called "tangenters," while dimorphs that move tractor 24 in direction 20, perpendicular to the tractee, are called "lifters."
FIG. 3 illustrates a pair of piezoelectric actuators A and B affixed to base 22 for moving and positioning tractee 26 (shown in phantom) by walking motion. A system for moving and positioning tractee 26 may comprise a plurality of actuators similar to actuators A and B. Motions of tractors 24a and 24b and tractee 26 are measured relative to fixed base 22. Electronic drives and connections are omitted for clarity. Tractors 24a and 24b are positioned electronically on predetermined paths, each path comprising a combination of tangenter motion, illustrated by arrows 28 and 34, and lifter motion illustrated by arrows 30 and 32. The electronic drive and controller (not shown in FIG. 3) control motions on the predetermined paths by applying appropriate electrical waveforms to the actuator segments. Tractors 24a and 24b alternately contact tractee 26 in walking fashion. Smooth walking produces substantially constant tractee velocity, constant net normal force applied to the tractee, constant net tangential tractive force applied to the tractee, and negligible sliding contact between tractors and tractee throughout the walking cycle. Negligible sliding contact, a major characteristic of smooth walking, promotes long-term stable operation, long life, and high electromechanical efficiency.
FIG. 4 is a schematic diagram of an embodiment of the electrical system of the present invention. The system comprises a controller 40, a plurality of electrical stimulators S 1 . . . S n connected to controller 40, a corresponding plurality of impedances Z 1 . . . Z n comprising individual segments of a transducer 42a, a corresponding plurality of second impedances Z' 1 . . . Z' n (that may comprise individual segments of a second transducer 42b, illustrated in phantom), and a plurality of electrical loops L 1 . . . L n connecting the corresponding stimulators and impedances. Impedances Z normally comprise electrical reactances, such as inductors and/or capacitors. In FIG. 4, the base of transducer 42a (and 42b) is fixed so that the motion of the top of transducer 42a (and 42b) corresponds to the mechanical output waveform. The use of transducer pairs, such as 42a and 42b, provides the benefits of system compactness and simplicity of construction. As connected in FIG. 4, transducer 42b provides an output complementary to that of transducer 42a, such as in the walking motion described above.
External electrical power is supplied to controller 40 on a line 44. Instructions, typically comprising an analog of the desired transducer output, are provided to controller 40 on a line 46. Using the supplied instructions, controller 40 computes and controls the distribution of electrical power to the stimulators to produce the desired transducer output. As an option, the system may include feedback lines 48a and 48b connecting transducers 42a and 42b, respectively, to controller 40. Feedback signals on lines 48a and 48b may represent transducer output states or the relative positions of transducer segments, for example. The amplitude of the electrical signal supplied to each stimulator is a periodic function of time. Each stimulator drives its loop with a resonant electrical signal. The frequency, amplitude, phase, and polarity of the desired response of each loop, represented by F 1 . . . F n , respectively, are determined by controller 40 from the instructions received on line 46. Resonance of the electrical stimulation is aided by the temporary storage of electrical energy in each loop impedance Z'. Impedances Z' may be separate components, or they may comprise output impedance circuits in the stimulators. In the preferred embodiment, impedances Z' comprise segments of second transducer 42b that correspond to the segments (impedances Z) of transducer 42a.
Controller 40 uses the Fourier theorem to select the frequency, amplitude, phase, and polarity of each segment response F. The resonant electrical signal provided on each loop produces the appropriate response F of that loop's actuator segment. The vector sum of the individual segment motions is the overall actuator output. This process is analogous to the synthesis of a nonsinusoidal electrical waveform by electrically adding a plurality of sinusoidal electrical signals. However, the present invention is distinguished from such prior systems by the absence of electrical summing and by the absence of mechanical resonance. The system of the present invention uses electrical resonance and mechanical summing to achieve the desired transducer output.
Transducers 42a and 42b of FIG. 4 may comprise segmented piezoelectric actuators as described above. In this embodiment, the impedances Z and Z' comprise piezoelectric dimorphs (individual dimorphs or groups of dimorphs connected in electrical parallel) that react electrically as capacitances. Referring to FIG. 5, dotted line waveform 50 is an ideal mechanical waveform of the tangential component of a two-axis piezoelectric actuator during smooth walking of an object positioned with constant velocity. Waveform 50 is a plot of tangential position of the actuator foot as a function of time. Tangential force is exerted during portion a of waveform 50 and removed during portion b. Retrace is accomplished during portion c, tangential force is reapplied during portion d, and the new tangential forcing cycle takes place during portion e. In this example, tangential waveform 50 is periodic with period lambda. With the use of bipolar piezoelectric shear elements, waveform 50 is symmetric about a quiescent mechanical position at 0 with extremes of tangential motion indicated as Y and -Y.
Referring to FIG. 6, waveform 52 illustrates actual tangential motion of a piezoelectric actuator having six segments whose individual tangential motions are summed as vectors. Actual waveform 52 is shown superimposed on ideal waveform 50. In theory, ideal waveform 50 can be achieved by summing the motions of an infinite number of actuator segments driven with separate loops. In practice, however, the sum of a relatively small number of segments adequately emulates the ideal waveform, as shown in FIG. 6.
FIG. 7 illustrates the plots of individual output waveforms F 1 . . . F 4 of the first four segments of an actuator. For the case of perfect actuator response, these curves correspond in phase and frequency to the electrical stimulations of loops L 1 . . . L 4 , respectively. In this example, half of the loops resonate with sine waves and the other half resonate with cosine waves. For piezoelectric walking, the force of tangential output is varied by adjusting the cosine amplitudes, while the speed of tangential motion is varied by adjusting the sine amplitudes.
Actuator force and speed may be varied independently and simultaneously. In the general case, all the actuator segments (e.g., dimorphs) are driven to the same peak potential that produces the most efficient but safe operation. Amplitude of the output motion of each segment can be changed by adjusting the size of the electrical impedance of each loop. For piezoelectric actuators, the capacitance of each segment can be modified by connecting different numbers of similar dimorphs in electrical parallel. This can be accomplished by the controller, for example, by using electrical switches (not shown) connected in the loops between the stimulators and the transducers. In the example illustrated in FIG. 7, the amplitude of F 1 is greater than that of F 2 because impedance Z 1 is greater than impedance Z 2 .
Referring to FIG. 8, waveform 54 is a dotted line plot of the ideal transducer output y as a function of time t for the perpendicular actuating portion (lifter) of a two-axis piezoelectric walking actuator. The actuator applies normal force to a tractee during portion a of waveform 54, removes normal force and lifts the foot clear of the tractee during portion b, awaits retrace by the tangenter during portion c, reapplies the foot to the tractee during portion d, and reapplies normal force during portion e for the next traction cycle. FIG. 9 shows a truncated series Fourier waveform 56, comprising the vector sum of six individual lifter segments, overlaid on the ideal waveform 54, illustrating the close approximation achieved with relatively few independently stimulated actuator segments.
The foregoing description has generally assumed linear actuator response to electrical stimulation. Actual transducers, however, have a nonlinear response. Bipolar driven shear piezoelectric actuators, when symmetrically stimulated to amplitudes lower than those causing saturation, have a nonlinearity, or hysteresis, similar to that illustrated in FIG. 10. The tractor position y is plotted in FIG. 10 as a function of applied electric potential e. An ideal linear transducer would respond as indicated by the dotted line 60. Curve 62 illustrates 30% lagging of actuator segment motion as the electric potential increases from the minimum potential -E, and curve 64 illustrates the same lagging as the potential decreases from the maximum of E.
FIG. 11 shows a quarter-cycle plot of the position of an actuator segment stimulated by a sine wave. The actual segment position 66 lags the ideal linear response 68 by the time alpha. Phase lag alpha is a time delay distortion caused by the piezoelectric hysteresis illustrate in FIG. 10. Actual response 66 also suffers from wave shape, or harmonic, distortion.
FIG. 12 shows a quarter-cycle response of a piezoelectric lifter. Dotted line 56 is the six-loop linear Fourier synthesized waveform of FIG. 9, and waveform 70 is the actual six-loop Fourier response including the time delay and harmonic distortions described above. To a first order approximation, the actuator time delay theta is the algebraic sum of segment delays alpha of FIG. 11, and the amplitude error beta is the algebraic sum of the harmonic distortions.
Referring to FIG. 13, waveform 70' is the actual six-loop Fourier response of FIG. 12 except that the time delays alpha are subtracted from respective loop activation times. This is called a phase, or time domain, correction. As illustrated in FIG. 13, corrections for alpha in the time domain significantly reduce the deviation from the linear synthesis of waveform 56. Because of the complex coupling of time delay and harmonic distortions, the amplitude error beta is also reduced. As a result, easily made time domain corrections provide a more accurate transducer output than that achieved from conventional whole-body drive of the same nonlinear transducer. In the preferred embodiment, controller 40 phase locks all loops to the loop having the highest frequency, thereby allowing relative phase corrections to be applied to the appropriate loops. Furthermore, the Fourier synthesis and time domain corrections practiced by the present invention reduce or eliminate many second order distortions such as piezoelectric drift.
Electrical transducers temporarily store electric and elastic energy. In an ideal resonant system, the stimulators supply only the electrical power that is to be converted into mechanical work, and the energy stored in loops as reactive power and elastic strain is recirculated without loss. Electrical loops for segmented transducers can be made with low resistance by eliminating semiconductor components. Semiconductors can be relegated to the controller sides of the stimulators, for example.
Many applications of the piezoelectric embodiment of the present invention allow substantial departure from the ideal smooth walking waveform. For example, a piezoelectric replacement for an hydraulic actuator allows considerably rougher running than a positioner for an optical element. For coarse running applications, a less accurate approximation of the Fourier sum can be tolerated. This allows connection of dimorphs into fewer series loops, which simplifies control. The relatively greater capacitance of larger dimorph groups may allow operation of each loop at a lower frequency, with larger charge transfer swings (i.e., reactive currents) that provide longer strokes. When each series loop is constructed with the least practical electrical resistance, very large reactive currents can be handled. When larger reactive currents flow with relatively reduced resistive dissipation, efficiency is improved. Large reactive currents also increase the speed of actuation, allowing greater power extraction from the actuators.
As an example of an alternative embodiment of the present invention, piezoelectric actuator capacitances can be replaced by inductances, each actuator inductance being a separate solenoid. In this embodiment, all members of a first group of solenoids are colinear around a magnetostrictive rod. The mechanical stroke at one end of the magnetostrictive rod is a nonsinusoidal waveform that is the truncated Fourier sum of the strokes induced by each solenoid. Capacitors or inductors can be used as ancillary electrical storage components in an embodiment not having a second group of electrically connected solenoids. With a second group of solenoids actuating a second magnetostrictive rod, each solenoid of the second group is connected to a respective solenoid of the first group in a loop similar to that previously described for piezoelectric dimorphs. In yet another embodiment, the dimorphs and solenoids described above can be replaced by actuators comprising electrically heated segments of a thermal expansion material. It can be seen from the foregoing examples that although the types of segmented actuators may vary considerably, the principles of the electrical drive system of the present invention remain the same.
A wide variety of stroke waveforms can be generated by the present invention by selection of appropriate loop frequencies and Fourier coefficient amplitudes. Uses for the various embodiments of the invention include smooth walking actuators, electromagnetic motors, and thermal expansion actuators. Nonsinusoidal periodic output is an advantage in many applications because predetermined portions of each actuator stroke may require different magnitudes of force, velocity, and acceleration.
Although the present invention has been described with respect to specific embodiments thereof, various changes and modifications may be suggested to one skilled in the art. Therefore, it is intended that the present invention encompass such changes and modifications as fall within the scope of the appended claims.
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An electronic system is provided for stimulating a segmented transducer with resonant electrical signals to produce a nonsinusoidal transducer output. In an illustrative embodiment, the transducer comprises a segmented piezoelectric actuator. The actuator comprises stacked piezoelectric dimorphs forming the actuator segments, each of which reacts electrically as a capacitance. Each segment (capacitance) is connected in a loop in electrical series with an external capacitor or a corresponding segment of a second actuator. An electrical controller stimulates each loop with a separate resonant electrical signal related to the others in frequency, phase, amplitude, and polarity. The resulting output of each actuator is the vector sum of the mechanical outputs of the individual dimorphs of that actuator. In an ideal resonant drive system for a segmented transducer, the only electrical energy used is that which is converted directly to mechanical work by the actuator. All other temporarily stored electric and elastic energy is recycled within the loops for high efficiency. When the electrical waveforms drive a pair of actuators, electrical charge oscillates between the actuators. Thus, loop currents flow between essentially lossless reactive components rather than through high-loss output devices.
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FIELD OF THE INVENTION
This invention relates to the production of banana starch using natural banana enzymes to break down the cell walls in a pulped banana slurry causing release of starch granules and allowing their recovery by filtration from the pulp residue and their separation from the aqueous dispersion by simple centrifugation.
BACKGROUND AND SUMMARY OF THE INVENTION
Banana starch is very likely to become a widely used starch commodity due to its desirable properties and to its potential production from low cost, cull bananas. It is known that about 25% of plantation grown bananas become culls. When banana bunches arrive at the central collection stations, bananas too small for shipping are removed along with those bananas that have damaged or spoiled areas that could cause microbial contamination of the bunch during shipping. This represents 25% of banana loss and a vast amount of financial loss.
If culls can be used for production of starch, they would represent a very large and significant source of starch that should be highly competitive in the world starch market. It would also improve crop economics and eliminate a large environmental problem.
To exalt the marketability of banana starch and lower its potential cost, I have developed a cost efficient process for producing starch from cull bananas. My process uses a minimum amount of processing chemicals, machinery and processing time. The new process comprises the step of steeping banana pulp with aqueous sodium bisulfite at pH of about 3.5 to about 5.5 for about 2 to about 8 hours, more preferably about 4 hours, at ambient to slightly elevated temperatures. During this steeping period the endogenous, banana enzymes such as pectinase, polygalacturonase, effectively work to disintegrate the plant cell walls allowing starch granules to be released into the aqueous steeping solution where they may be recovered by filtration through wire screens to remove cell walls and other non-starch pulp mass material and subsequent centrifugation.
DETAILED DESCRIPTION OF THE INVENTION
The present invention comprises pulping green bananas in water under conditions to obtain maximum cell wall breakdown without starch degradation. This is done by mechanically comminuting green bananas in the presence of about 0.5 to about 3.0% by weight, more preferably about 1% by weight sodium bisulfite solution at a pH of about 3.0 to about 5.5, more preferably at a pH of about 3.5 to about 5.2 and at about 20° to about 50° C., more preferably at ambient temperature providing optimum conditions for activation of the natural polygalacturonase and other enzymes that actively hydrolyze cell walls to open the plant cells and allow effective release of the starch granules. After about 2 to about 8 hours, most typically about 4 hours steeping time, the pulp is screened to remove fiber and the filtrate is then centrifuged to obtain granular banana starch in very good yield.
Green bananas or banana culls are separated from freshly harvested bunches and are quickly sliced and pulped in a blender, such as a Waring blender or its equivalent commercial type, with a 1% by weight sodium bisulfite water solution at pH 4 to 5.2 initially at ambient temperature. The temperature may rise, due to pulping energy input, to 40°-50° C. The resulting dispersion is allowed to stand or is slowly stirred for about 4 hours and filtered on a 75 micron sieve. The filtrate is centrifuged to settle the starch granule layer which may be surface scrapped to remove residual protein and then dried. Normally, any Steeping temperature below gelatinization of starch may be used.
EXAMPLE I
Green banana slices (100 grams; 5 mm thick) were placed in 200 g of 1% sodium bisulfite solution at pH 4.5 and blended in a Waring blender for 10 minutes and allowed to stand at 40° C. for 4 hours. The mixture was then filtered on a 200 mesh screen to remove pulp which was washed with a small amount of water. The filtrate was first centrifuged at 100×g to remove residual peel and fiber in the starch slurry. Thereafter the decanted starch slurry was centrifuged at 1000×g to precipitate the starch. The yield of dried banana starch from green bananas obtained from a wholesale banana warehouse was 20.1%.
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A process is described for isolating granular starch from bananas by making use of sodium bisulfite and naturally occurring enzymes in the bananas to promote release of starch granules from the banana fruit.
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FIELD OF THE INVENTION
[0001] The present invention concerns a tile built applying at least one metallic layer, in stainless steel or other metals, on a substratum like, as example, a sound-deadening or a thermosetting plastic material; a number of such tiles may be used to cover surfaces in the building filed. Characteristic of these tiles is that the tile sides are properly shaped to join the tiles together to realise stable, plane and continuous coverings.
[0002] The surfaces to be covered could be horizontal, as a floor, or tilted, up to be vertical as are building facades or inner walls. Tiles format is normally square or rectangular, even if there aren't limits to format type provided that the sides are made to be joined together. The invention concerns also a corresponding method to realise such tiles and the coverings obtained installing the tiles on suitable plane surfaces. Similar tiles are known being made by a metal plate bonded, with various methods, to a substratum of a non metallic material like, but not only, a plastic material. To apply such tiles multiple methods exists, but all of them are time consuming, needs skilled people, and are costly. Moreover the tiles implantation to the rough support requires costly adhesives or similar, that frequently become a critical factor when exposed to humidity or to wide thermal excursions.
[0003] An object of the present invention is to propose a new tile of the type and for the applications just described, together with the method to realise it; the tile is carefully designed to make the implantation easy, fast and cheap without using adhesives to fix it to the basement. The essential characteristics of the new tile, of his realisation method, and of the coverings obtained joining a number of such tiles, are defined by the enclosed claims. Further characteristics and advantages of the solution, according to the present invention, will be apparent from the description given below of preferred embodiments, given purely as an indicative example without limitations, with reference to the enclosed figures, in which:
[0004] FIG. 1 illustrates, in a schematic way, a tile in section according to the invention.
[0005] FIG. 2 is a plane view from the bottom of the tile of FIG. 1 .
[0006] FIG. 3 is a section to show the details of the coupling of two tiles of the type represented by FIGS. 1 and 2 .
[0007] FIG. 4 shows in a section details of the possible implantation of a tile to the basement and reinforced tiles having two metal layers.
[0008] FIG. 5 shows a different realization of the tile's coupling.
[0009] FIG. 6 shows the same coupling of the previous FIG. 3 , modified to allow the removal of a single tile from a complete pavement.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0010] With reference in particular to FIGS. 1 and 2 , a tile 10 is illustrated, the tile being composed by a metallic plate 12 , preferably but not exclusively, in stainless steel, and by a suitable plane substratum 14 , made as example by sound-deadening or thermosetting plastic material. The metallic plate 12 , that's the stamping surface or the top external surface of the covering realised assembling these tiles is coupled to the substratum 14 by any suitable way, like, as example by bonding with adhesive. Moreover, when out of ordinary mechanical performances are required, given that a single metallic layer cannot exceed a certain thickness because of the surface's shaping process, the tile could be built coupling more than one metallic plate, as example with two of them.
[0011] The tiles, will be installed on a base surface to be covered, normally a plane surface, horizontal in case of floors or tilted as in case of slope coverings, up to vertical when covering facades or internal walls.
[0012] To guide and join together adjacent tiles 10 , each tile shows, on one side, or preferably on two consecutive sides, a female shaped joint; the opposite sides are properly male shaped, these elements being obtained by the edges of the metallic plate of which the tile is composed. It is important to highlight that the tile joints according to the present invention, are made of homogeneous material, in the case metal, folded without soldering or other complex workings. Moreover, as per FIGS. 1 and 2 , where the tile shown has one metallic plate 12 , the four lateral profiles are external to the substratum 14 and properly folded to obtain said male and female joints. The method to get the female profile 16 , is to make a first fold 18 of the ending side of the plate versus the tile inner, and a second fold 20 , in the opposite direction to obtain an open “Z”, with an externally facing seat 22 parallel to the tile side. The global thickness of the “Z” fold is a bit less of the total tile thickness, to assure planarity. The seat 22 of the female 16 , is dimensioned to host a free edge 24 of a contiguous tile, said edge being part of a male element 26 result of folding down and then externally as in 28 the metallic side of the tile to obtain a substantially “L” shaped profile, where the free side 24 has a proper quote to perfectly fit inside the “V” seat 22 .
[0013] With reference to FIG. 2 , a rectangular tile 10 is illustrated, having two female elements 16 on two contiguous sides, and two male elements 26 on the contiguous opposite sides. To avoid metal interferences during folding and to well close the tiles one near to the other during implantation, the angles of the rough metal plate 12 are properly cut as per FIG. 2 , detail 32 . To be noticed that cuts at the angles, are made to get a completely continuous and closed tile plane when installed. It's also possible to build tiles having only two joint, typically on the longest dimension, instead of the four shown and described; this two side insertion tile, is preferred for long and tightened tiles and results cheaper.
[0014] Moreover the female joints 16 can be formed by single sub-elements 18 ′ obtained with cuts 18 ″ perpendicular to the tile edge, and folding lines 20 can be previously traced on the tile rear surface to improve the folding precision. With reference to FIG. 3 , details of a couple of tiles are shown, to highlight the joint of a male element 26 ′ and of a female element 16 , belonging to two adjacent tiles 10 ′ and 10 covering a surface 33 .
[0015] When the surface 33 is horizontal, it's normally not necessary to fix the tiles to the surface; anyhow, in case where the fixing is desired or preferable, the female edge 34 can be foreseen few millimetres longer to accept fixing screws, 38 on holes 36 , as shown in FIG. 4 . FIG. 4 illustrates two tiles 10 ″ and 10 ′″, having metal plates 12 ″ a , 12 ″ b and 12 ′ 41 a, 12 ′ 41 b respectively, the male and female profiles being obtained by folding the metal plane of the external plates 12 ″ a and 12 ∝″a.
[0016] However the male and female joints can be obtained by folding the inner plates 12 ″ b and 12 ′″b.
[0017] An even simpler fixing, is possible on the “L” shaped side as it happens at the ending lane of the coverings.
[0018] Due to the characteristics of the present invention, the implantation of tiles results simple, fast, and precise; the covering is aesthetically very clean, without visible screws with the metal tiles quite continuous. The metal joints, as made, allows the recovery of small planarity defects frequently present on the base rough surfaces, and compensate the dimensional changes due to temperature variation. An important advantage of the invention is that the metal tiles are electrically interconnected by a practically infinite number of points, this makes very simple the metal grounding of the complete covering when requested.
[0019] With reference to FIG. 5 , a different form of the invention is shown; with reference to two tiles 40 and 40 ′, each having a metal plate 42 and 42 ′, coupled with a substratum 44 and 44 ′, standing on a surface 45 . As per this implementation, the female joint element 46 is built folding the metal edge firstly down and secondly up; this realises a “V” seat 48 , where to insert a free folded down edge 50 ″ of the male element 52 . Also with this implementation the joints could be two or four on the sides of each tile.
[0020] It's a general good practice, to simplify the replacement of eventually damaged tiles or to give access to under covering installations, to interpose to normal tiles special easily removable “jolly” tiles without joints or with joints of reduced length as shown in FIG. 6 where, as example, the joining “Z” profile 16 h of the tile 10 h has an inner edge shorter than the equivalent one of the tile 10 in FIG. 3 .
[0021] As an alternative (not shown), the “jolly” tiles can be formed without joints and maintained in position on the ground surface by means of magnetic attraction between permanent magnetically attracting elements, embedded in the ground surface and in the bottom surface of the tile substratum.
[0022] To build the tiles, according to the present invention, a metal plate is properly cut at dimension and the plate corners are cut with a number of additional cuts made because beneficial to the precision of the folding process; as example, the line of folding can be properly engraved to improve precision.
[0023] The plate is then folded, in multiple steps, to get the tile metal plate complete with its female and male side profiles. Finally the tile is assembled with an eventual second metal plate, and the substratum. The covering made without screws with tiles produced as per the invention, keeps the lower surface exactly as it was before. This is very desirable and allows temporary installations and tile reusability, important characteristic for a number of applications, as example like the fair stands floors or the technical floors.
[0024] In conclusion the present invention realises, with limited investments, simple, flexible and cheap metal covering tiles characterised by an easy, adhesive free installation method, and by a very clean aesthetic, without visible screw or other heterogeneous components. The peculiarity of the metal joint is beneficial to recover the small planarity defects of the installation surface, important to compensate dimensional changes due to the thermal excursion and allows easy electrical grounding.
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This invention relates to a tile for covering surfaces in the form of one or more metallic plates and a substratum to be placed on the surface to be covered. At least one metal plate has folds forming male and female shaped elements to be connected with those of adjacent tiles to form a substantially continuous coverage.
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BRIEF SUMMARY OF THE INVENTION
To assist in the radiography of sick, newborn infants it is important to position the infant with respect to the x-ray plates or films in a particular fashion and at a particular, selected distance. This is advisable to get as clear an exposure, and preferably as magnified an exposure, as possible. A difficulty is that the infant should be handled and disturbed just as little as possible, yet must have his relationship to the x-ray film or plate controlled and arranged as precisely as possible. This is accomplished by maintaining the infant in an incubator or comparable enclosure in accordance with the preferred general practice and then providing a tray for use within the incubator. The tray supports the infant above a bottom area of the tray transparent to x-rays and is movable by means of an elevator to the desired or selected distance above an x-ray film or plate on or below the bottom of the tray beneath the x-ray transparent area. Also, the tray is preferably provided with means for engaging various life-supporting and monitoring tubes or connectors and holding them stationary with respect to the infant. The tray can nevertheless be moved within the incubator while the infant thereon remains connected, without disturbance, to his life-sustaining and observational attachments.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is an isometric view showing an infant elevator arrangement in connection with a cooperating incubator mechanism positioned in the vicinity of an x-ray device, some of the portions being shown in their positions between x-ray exposures.
FIG. 2 is an isometric view of an infant in an infant tray of the sort utilized in connection with the structure of FIG. 1, certain portions of the attendant mechanisms being omitted for clarity and other portions being broken away to reduce the size of the figure.
FIG. 3 is a fragmentary cross-section, the plane of which is indicated by the line 3--3 of FIG. 1.
FIG. 4 is a cross-section on a vertical plane transversely through the incubator showing the construction of the tray and the position of the x-ray cassette.
DETAILED DESCRIPTION
There are numerous problems in deriving x-ray showings from sick, newborn infants, yet such technology is highly valuable in assisting in saving infant lives. It is customary to house such an infant on a table within an enclosure having a controlled atmosphere, such a device often being referred to as an incubator. When in the incubator, the infant is often connected by tubes, wires and other connectors with various life-supporting or factor-recording devices outside of the incubator and is generally under observation in a highly controlled environment. If, then, x-ray pictures are required of the infant so situated, a number of problems arise, not only with respect to the desirability of disturbing the infant as little as possible, but also in arranging matters geometrically so that usable x-ray prints or plates can be obtained.
Pursuant to the present invention, some relatively standard mechanisms are particularly adapted, combined and improved to provide a facility which permits taking of x-rays under normally adverse conditions but with very little or no disturbance of the infant and yet with quite usable results.
In a typical environment, there is afforded an x-ray machine 6 of any standard kind which has an effective picture-taking head 7 disposed at an appropriate elevation above the floor 8. Resting on the floor is a cabinet 9 forming part of an incubator, generally designated 11, and inclusive of a supporting table 12 (FIG. 4) arranged at an appropriate and convenient height above the floor 8. The table may, if desired, have a depressed, central panel 10. The space above the table 12 is enclosed almost entirely by a hood 13 preferably of transparent material. The hood is inclusive of a top panel 14 disposed just below the x-ray head 7, a rear panel 16 designed to clear the x-ray machine 6 and particularly the head 7 thereof, a pair of end panels 17 and 18, and a front panel 19 conveniently connected to the top panel 14 by a longitudinal hinge 21.
The front panel can be swung up and swung down to afford access to the interior of the incubator or to be closed generally to isolate the interior of the incubator. It is customary to provide hand openings 22 in the panel 19. The interior of the incubator is connected to suitable atmospheric regulating structures, the details of which are not important herein. The atmosphere within the incubator is maintained at selected temperatures, humidities and air flow velocities in accordance with the requirements of the attending physician.
In many instances the infant is put onto the table 12 on a relatively thin, x-ray transparent mattress or comparable support and very often the infant is connected by tubes 26 or wires 27 or the like to exterior instrumentalities. These leads, such as 26 and 27, are taken from the exterior into the interior of the incubator, preferably through notches 28 provided at intervals around the edges of the end panels thereof, the notches being relatively small and thus not interfering particularly with the interior ventilation of the structure.
In accordance with the present invention, the mattress within the incubator may be dispensed with and can be replaced by or can be used with an infant tray 31 that is readily received within the incubator hood and occupies much of the area of the table 12 thereof. The tray conveniently is a one-piece molding of an x-ray transparent, plastic material. It has its own end walls 32 and 33 joining its own side walls 34 and 36 and has its own bottom wall 37 or floor. In this instance, the floor 37 is not completely integral, but rather has a relatively large, central, rectangular portion given over to an x-ray transparent, thin plate 38 of "Lexan" or other comparable light polycarbonate.
In addition, the tray side walls, at least some of them, are preferably provided with interruptions in the form of notches 39 in position for conveniently receiving conductors such as the wires and tubes 26 and 27. These can be temporarily anchored therein against endwise or sidewise movement by grommets 41 or by adhesive tape. While the portions of the conductors 26 and 27 outside of the tray can easily be moved and can be extended in any desired fashion through the interior of the incubator to extend therefrom through the notches 28, nevertheless there is no substantial movement of any such conductor on the inside of the tray and adjacent or relative to the infant.
The tray also includes a pair of parallel tubes 46 and 47 extending generally longitudinally thereof but outside the area of the window 38 and effective as to their position and arrangement readily to receive a pair of lift rods 48 and 49. These extend parallel to each other from an elevator head 51 at the upper end of an elevator plunger 52 vertically reciprocable in an elevator housing 53 having a spider support 54 on the floor 8.
Since the rods 48 and 49 are not always to be engaged with the tubes 46 and 47, but since they must be able to move vertically with respect to the housing 11, certain provisions are made. Preferably the end wall 18 is provided with a pair of vertical slots 56 and 57 extending from the table 12 upwardly very nearly to the top panel 14 of the hood 13. The slots are of adequate dimension easily to receive and pass the rods 48 and 49, and even to allow a little leeway for lateral displacement. In order to preclude the slots interfering with the air conditioning within the hood 13, there are provided covers 58 and 59 secured to the upper portion of the end wall 18 by swinging fasteners 61. The covers normally hang by gravity over the slots 56 and 57 and close them, but readily can be displaced laterally when the rods 48 and 49 are to be positioned therethrough.
In many instances, the incubator 11 and the elevator 53 are sufficiently stable so that they need not be especially interrelated, but under other circumstances and depending on some of the other surroundings, it is advisable in many cases to augment the elevator. There is then provided around the upright 53 a frame 62 of substantially the width of the housing 9 and having facing screw clamps 63 and 64 freely mounted thereon. With this arrangement, the elevator can be clamped to the incubator so that there is no possibility of relative dislodgment between them.
In a typical use of this structure, an infant is placed on the "Lexan" floor portion 38 either directly or on a relatively thin, x-ray transparent, small blanket. The infant is provided with the necessary and customary connectors and tubes 26 and 27. These are engaged with the side walls of the tray 31 either by means of the grommets 41 or by means of adhesive tape straps, so that there is no relative movement between the tubes 26 and 27 and the infant on the inside of the tray, although there is such movement possible on the outside of the tray. The tubes and wires then extend through the openings 28 in the side walls of the incubator to the appropriate external equipment to which they pertain.
When an x-ray exposure is to be made, the elevator 53 is wheeled into the vicinity of the incubator and an actuating handle 71 on the elevator upright is operated to bring the height of the rods 48 and 49 substantially level with the position of the tubes 46 and 47 on the tray. The elevator is shifted laterally until the rods and tubes line up. If desired, the rods 48 and 49 can be advanced or retracted and then fastened in place by thumb wheels 72 in order to adapt the elevator mechanism to the particular tray and incubator being encountered. Thereupon the elevator is moved toward the incubator with the rods 48 and 49 passing through the slots 56 and 57, the closure plates 58 and 59 being moved aside for that purpose. The rods 48 and 49 are further advanced into the tubes 46 and 47 for substantially the full length of the tray.
When the elevator has been advanced to that extent, the clamps 63 and 64 are then engaged with the sides of the incubator support cabinet 9 and are tightened so that the incubator and elevator are locked together temporarily. Thereupon, the actuating handle 71 for the elevator is again actuated in a slow, deliberate fashion and then is effective to lift the tray 31 with the infant on it away from the table 12 up toward the x-ray head 7 near the top of the hood 13. At a convenient height, x-ray pictures are taken utilizing an x-ray cassette 74 which has previously been placed on the table 12 beneath the tray and the infant. Such plate positioning is facilitated by cutouts 76 in the side walls of the tray. The elevator can be moved up and down without in any fashion disturbing the connectors 26 and 27 so far as the infant is concerned.
When the x-ray pictures have been taken, the clamps 63 and 64 are released, the elevator 53 is lowered to the bottom and is withdrawn or is moved away from the incubator as the rods 48 and 49 are extracted from the tubes 46 and 47. The cover plates 58 and 59 fall by gravity into position over the slots 56 and 57, so that the infant within the incubator is again enclosed. It has been found in actual practice that it is possible to get good x-ray photographs of sick, young infants without adversely disturbing them in any fashion.
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An infant incubator includes a table with an enclosing hood movably overlying the table. To work with the incubator, an exterior elevator can be clamped in position relative to the table and has a plunger movable vertically relative to the table. There are lifting arms on the plunger adapted to extend through slots in the hood and into engagement with arm-engaging means on an infant tray adapted to rest on the table beneath the hood. The tray preferably has an x-ray transparent bottom area and is movable by the lifting arms into various positions above an x-ray cassette on the table beneath the bottom area. Tubes and connectors can be fastened to the tray so as to move therewith as the elevator plunger operates the tray.
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This is a continuation of application Ser. No. 639,243 filed on Jan. 9, 1991, now U.S. Pat. No. 5,125,243.
FIELD OF THE INVENTION
The present invention relates in general to refrigeration devices and in particular to devices for cooling fluids.
BACKGROUND OF THE INVENTION
Airconditioning systems for vehicles are well known and are used, particularly in hot climates, fop cooling the interior of a vehicle. It is also known to use an existing vehicle air conditioning system to cool articles of food and drink being carried in a vehicle.
There is described in U.S. Pat. No. 4,103,510 a portable cooling chest operatively attachable to an automobile air conditioning system. The system comprises a portable cooling chest having a durable outer shell and an inner liner, each with bottom and side wall members and includes a unitary middle liner arranged in proximity to the bottom and side wall members of the outer shell to define an insulating compartment and in proximity to the bottom and side wall members of the inner liner to define a sealed cavity circumscribing the inner liner and containing eutectic fluid and immersed heat exchange coils. The heat exchange coils, coupled through a quick connect/disconnect means to the refrigerant of an automobile refrigeration system, circulate chilled refrigerant to chill and freeze the eutectic fluid within the sealed cavity and cool the interior space of the cooling chest.
A disadvantage of the cooling chest described in the above-mentioned U.S. Patent is that it is bulky and invariably takes up space, for example, in the baggage compartment of a vehicle. In addition, access to the cooling chest is not possible from the interior of the vehicle. Furthermore, as articles placed in the cooling chest are cooled by virtue of the entire interior volume thereof being cooled. This way of cooling is relatively slow and inherently wasteful of energy.
There is described in U.S. Pat. No. 3,858,405 a removably positioned refrigerated chest for motor vehicles. U.S. Pat. No. 4,483,151 describes a car airconditioner with a freezer/refrigerator chamber. U.S. Pat. No. 4,483,151 describes a refrigeration system having two evaporators, one of which provides general air conditioning and the other being provided for cooling a cooling chamber. As in U.S. Pat. No. 4,103,510, cooling apparatus employing a cooling chamber or the like is inherently slow and wasteful of energy.
U.S. Pat. No. 3,912,475 describes a combined air conditioner, beverage cooler and engine efficiency booster. The beverage cooler comprises a pair of beverage cooling coils associated with a gasoline engine with a fuel intake providing a source of reduced pressure.
A particular disadvantage to the airconditioner and beverage cooler of the above-referred to patent is that it is not useful with vehicles not having the described fuel intake which provides a source of reduced pressure, nor may it be appended, if so desired, to an existing, conventional vehicle airconditioner.
Disclosed in U.S. Pat. No. 3,553,976 is a container refrigerator which is adapted for attachment to the outside of a container. A refrigerating member is a tubular member, the configuration of which is either that of a C-shaped ring member that can be expanded and snapped onto a cylinder or that of a helically coiled tube that can be expanded and slid onto the container and released to be held in place. The refrigerating member holds a refrigerating medium which can be vented for reduction of temperature and the medium can be expanded between portions of the refrigerating member.
There is also described, in U.S. Pat. No. 4,711,099, a portable quick chilling device for cooling a beverage in a twelve ounce can from about 24 degrees Celsius to about 7 degrees Celsius in approximately four minutes. The evaporator of the device comprises a coil of tubing shaped to receive a generally cylindrical object to be chilled. There is also described apparatus for opening the coil so as to enable insertion of the beverage can thereinto and for closing the coil such that it tightly grips the can.
In U.S. Pat. No. 4,653,289 there is described a vehicle airconditioner ventilator-mounted receptacle for storage and cooling of food, drink or the like. The cooling of the goods contained within the receptacle is provided by circulation therewithin of the cool air flow from the ventilator. A disadvantage of this receptacle is that, as described in the examples, the temperature of goods cooled in the receptacle may be reduced in a relatively long time to a final temperature that is higher than the temperature of the cooled air circulated therearound.
Disclosed in U.S. Pat. No. 2,401,613 is a storage and cooling receptacle for use with a domestic refrigerator.
SUMMARY OF THE INVENTION
It is an aim of the present invention to provide an energy efficient, relatively inexpensive system for rapid cooling of individual standard-sized fluid containers. Preferably, the system is mounted in a vehicle.
There is thus provided in accordance with a preferred embodiment of the present invention a system For cooling fluid stored in a generally cylindrical container, the system including a generally cylindrical hollow coil element having an engaged orientation fop engaging the container and at least one disengaged orientation in which the container is disengaged, the hollow coil element being configured to provide thermal engagement between a refrigerant fluid located interiorly thereof and the container when the hollow coil element is in the engaged orientation, the hollow coil element including at least one elongate hollow element with a nonuniform generally spiral configuration, the spiral defining a plurality of turns of the elongate hollow element.
Further in accordance with a preferred embodiment of the present invention, the hollow coil element is configured such that, when the orientation thereof changes from at least one of the at least one disengaged orientations to the engaged orientation, the turns of the elongate hollow element tighten around the container in a predetermined order.
Still further in accordance with a preferred embodiment of the present invention, the moments of inertia of the cross sections of the hollow element are non-equal.
Additionally in accordance with a preferred embodiment of the present invention, the generally cylindrical configuration includes a substantially conical configuration, thereby defining first and second ends of the hollow coil element, the diameter of the turn at the first end exceeding the diameter of the turn at the second end.
Further in accordance with a preferred embodiment of the present invention, the at least one disengaged orientation includes a first receiving orientation in which the coil element is configured to receive the container and a second at-rest orientation in which the coil element is at rest, and the diameters of the plurality of turns are non-equal at least when the hollow coil element is in the at-rest orientation.
Additionally in accordance with a preferred embodiment of the present invention, the diameter of the cross-section of the container exceeds each of the diameters of the plurality of turns when the hollow coil element is in the at-rest orientation.
Further in accordance with a preferred embodiment of the present invention, the cooling system also includes orientation changing means For selectably changing the orientation of the hollow coil element From a one of the engaged and disengaged orientations to another of the engaged and disengaged orientations.
Further in accordance with a preferred embodiment of the present invention, the orientation changing means includes a spring.
Additionally in accordance with a preferred embodiment of the present invention, the cooling system also includes hollow coil element securing means for securing an end of the hollow coil element, thereby defining a fixed end of the hollow coil element and a free end thereof, and wherein the orientation changing means includes means for rotating the free end about the axis of the generally cylindrical hollow coil element at a relatively high angular velocity.
Still further in accordance with a preferred embodiment of the present invention, the diameter of the turn at the fixed end of the hollow coil element exceeds the diameter of the turn at the free end thereof.
Additionally in accordance with a preferred embodiment of the present invention, the moment of inertia of the cross section of the turn at the fixed end of the hollow coil element exceeds the moment of inertia of the cross section of the turn at the free end thereof.
Still further in accordance with a preferred embodiment of the present invention, the cooling system is characterized in that when the container is placed within the hollow coil element and the free end of the hollow coil element rotates about the axis thereof, the container also rotates about the axis.
Further in accordance with a preferred embodiment of the present invention, the fluid stored in the container includes a gaseous liquid and the cooling system also includes cooling control means for controlling the cooling of the coil, thereby to generally prevent forceable ejection of the liquid from the container when the container is opened.
Additionally in accordance with a preferred embodiment of the present invention, the cooling control means includes temperature control means For sensing and controlling the temperature of the coil.
According to a further preferred embodiment of the present invention there is provided a system for cooling gaseous fluid stored in a selectably disengageable container, the system including receiving means for selectably receiving the container, cooling means for providing a refrigerant fluid in thermal engagement with the container and means for substantially preventing forceable egress of the gaseous fluid from the container when the container is opened.
Further in accordance with a preferred embodiment of the present invention, the cooling means includes a coil through which said refrigerant fluid flows and the means for preventing comprises temperature control means for sensing and controlling the temperature of the coil.
Still further, in accordance with a preferred embodiment of the present invention, the temperature control means maintain the temperature of the coil generally above -7 degrees Celsius. Alternatively, the temperature control means are operative to cease the operation of the cooling means when the temperature of the coil drops below generally -7 degrees Celsius and renew the operation of the cooling means when the temperature rises generally above +1 degree Celsius.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be understood and appreciated more fully from the following detailed description taken in conjunction with the drawings, in which:
FIG. 1A is an illustration of beverage cooling apparatus constructive and operative in accordance with a preferred embodiment of the present invention, in an open orientation prior to insertion of a beverage container;
FIG. 1B is an illustration of the beverage cooling apparatus of FIG. 1A, in a first open orientation following insertion of a beverage container;
FIG. 1C is an illustration of the beverage cooling apparatus of FIG. 1A, in a closed orientation following insertion of a beverage container;
FIG. 2A is a top sectional illustration of the bottom portion of the beverage cooling apparatus of FIGS. 1A-C, when in either one of the open orientations of FIG. 1A and FIG. 1B;
FIG. 2B is a top sectional illustration of the bottom portion of the beverage cooling apparatus of FIGS. 1A-1C, when in the closed orientation of FIG. 1C;
FIG. 3A is a side sectional illustration of the bottom portion of the beverage cooling apparatus of FIGS. 1A-1C, when in either one of the open orientations of FIG. 1A and FIG. 1B;
FIG. 3B is a side sectional illustration of a portion of the beverage cooling apparatus of FIGS. 1A-1C, when in the closed orientation of FIG. 1C;
FIG. 4 is a front view illustration of the beverage cooling apparatus of FIGS. 1A-1C, when in the closed orientation of FIG. 1C;
FIG. 5A is a side view illustration (not to scale) of the coil of the beverage cooling apparatus of FIGS. 1A-1C, when in the first open orientation of FIG. 1B;
FIG. 5B is a side view illustration (not to scale) of the coil of the beverage cooling apparatus of FIGS. 1A-1C, when in the closed orientation of FIG. 1C;
FIG. 6A is a block diagram illustration of a cooling control system constructed and operative in accordance with a first preferred embodiment of the present invention and useful in conjunction with the beverage cooling apparatus of FIGS. 1A-5B;
FIG. 6B is a schematic illustration of electronic circuitry useful in implementing the cooling control system of FIG. 6A;
FIG. 7A is a block diagram illustration of a cooling control system constructed and operative in accordance with a second preferred embodiment of the present invention and useful in conjunction with the beverage cooling apparatus of FIGS. 1A-5B;
FIG. 7B is a schematic illustration of electronic circuitry useful in implementing the cooling control system of FIG. 7A;
FIG. 7C is a schematic illustration of electronic circuitry useful in an alternative implementation of the cooling control system of FIG. 7A;
FIG. 8A is a block diagram illustration of a cooling control system constructed and operative in accordance with a third preferred embodiment of the present invention and useful in conjunction with the beverage cooling apparatus of FIGS. 1A-5B;
FIG. 8B is a schematic illustration of electronic circuitry useful in implementing the cooling control system of FIG. 8A;
FIG. 8C is a block diagram illustration of a proposed cooling control system which is a variation of the cooling control system of FIG. 8A; and
FIG. 9 is a cross sectional illustration (not to scale) of the coil of the beverage cooling apparatus of FIGS. 1A-1C, constructed and operative in accordance with a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Reference is now made to FIGS. 1A-4, which illustrate beverage cooling apparatus, referenced generally 10, being constructive and operative in accordance with a preferred embodiment of the present invention and having a first open orientation and a second closed orientation. The apparatus defines a generally cylindrical beverage container receiving volume 12. The apparatus comprises a cover 14, a top support portion 16 to which the cover 14 is hingeably attached, a bottom support portion 18, and a generally planar vertical support portion
Top support 16 is generally planar and has a circular aperture 22 formed therethrough, through which the container is inserted.
Bottom support portion 18 comprises a horizontal generally planar base to which is rotatably attached, as by means of a bolt 25, generally cylindrical container receiving means 26.
Vertical support 20 typically comprises means for attaching the apparatus 10 to a vehicle, such as apertures 28 through which screws may be passed. Vertical support 20 also typically comprises apertures (not shown) through which electrical connections to the cooling controls shown and described hereinbelow may pass.
There is also provided a hollow spiral coil 130 (shown in FIGS. 5A and 5B), through which refrigerating fluid may flow, surrounding the container receiving volume 12. A first fixed end of the coil is secured to the top support portion 16 and a second rotating end of the coil is fixedly attached to the container receiving means 26 (preferably at two attachment locations 27, as best seen in FIGS. 2A-2B) such that the rotating end of the coil and the container receiving means 26 rotate together.
In accordance with a preferred embodiment of the present invention, coil 130 is operative to cool a beverage container with which it comes into contact. In an at-rest state, the inner diameter of coil 130 is less than that of a standard beverage container. Therefore, to insert a beverage container into coil 130, coil 130 has to be twisted open into an open orientation. The beverage cooling apparatus 10 is operative to open coil 130 to enable the insertion of the beverage container and to enable coil 130 to close around the beverage container so as to provide close contact between the coil 130 and the container, as described in detail hereinbelow.
There is also provided a first generally elongate element 40, comprising a generally upright elongate portion 42, a spring engaging portion 44 engaging a first end of a spring 46, and a container elevating portion 48. Generally elongate element 40 is pivotably and slidably mounted at a mounting location 50, such that it can pivot toward and away from the plane defined by vertical support and such that it can slide down into a guiding track 52, typically integrally formed with the bottom support portion 18 and associated with an opening 53 in the floor of bottom support portion 18 and configured and arranged to mate with container elevating portion 48.
The downward sliding movement of generally elongate element 40 is controlled by a protrusion 54 which extends generally perpendicularly to the plane defined by the cover 14 and which enters a protrusion receiving opening 56 provided in the top support portion 16. Protrusion 54 is preferably integrally formed with the cover 14.
There is further provided a second generally elongate element 58 comprising a spring engaging portion 60 for engaging a second end of the spring 46 and a cup engaging portion 62 for engaging the container receiving means 26, typically via an aperture 64 in a protruding portion 66. Protrusion 66 protrudes outwardly from and is preferably integrally formed with the container receiving means 26. Second generally elongate element 58 is pivotably joined to vertical support 20, as by a screw and bolt arrangement (not shown).
There is also provided a cover engaging element 70 which is pivotably mounted, at a first end thereof, to the cover 14 as by being bent around an elongate element 72 fixedly attached to the cover 14. The cover engaging element pivots about the axis defined by elongate element 72 when the cover is opened or closed. At a second end 74 thereof, the cover engaging element 70 engages the second generally elongate element 58. The cover engaging element 70 passes through an opening 76 provided in top support portion 16.
Container receiving means 26 is formed with an L-shaped aperture 78 in the wall thereof, best seen in FIGS. 3A and 3B, the longer arm 80 of which is generally circumferentially arranged and contacts the floor of container receiving means 26, and the shorter arm 82 of which is generally axially arranged with respect to an axis 84 (FIGS. 2A-2B) of the cylindrical volume 12. An opening 85 in the floor of container receiving means 26 is arranged generally opposite the shorter arm 82. The aperture 78 is arranged relative to the container elevating portion 48 such that, when the cover is opened, the container elevating portion 48 slides along long arm 80 of the aperture and toward short arm 82, and then up short arm 82. A stopper (not shown), typically integrally formed with the bottom support portion 18, is arranged to contact the tip 88 of the long arm 80.
The mechanical operation of the apparatus 10 will now be described. Assuming the apparatus is in the open orientation of FIG. 1A, a beverage container (not shown) is inserted by a user of the apparatus through aperture 22 and is pushed downwards by the user, through coil 130 (not shown), pushing down container elevating portion 48 until the container is fully seated within container receiving means 26. In this position, shown in FIGS. 1B and 2A, the container receiving means opening 85 and the bottom support portion opening 53 are arranged one opposite the other.
In response to the movement of the beverage container, container elevating portion 48 slides down arm 82 of aperture 78, descends through both openings and protrudes somewhat below bottom support portion 18 and the top tip 100 of the first elongate element 40 is aligned opposite a contacting portion of cover protrusion 54. In this position, portion 48 blocks the movement of container receiving means 26.
The cover 14 is then closed by the user of the apparatus. The cover engaging element 70 releases the second elongate element 58. The cover protrusion 54 descends along a path generally perpendicular to the plane of the cover 14 and urges the first elongate element 40 further downward into its track 52. Portion 48 of elongate element 40 is forced thereby from its rotation blocking engagement with the floor of container receiving means 26 to a position below container receiving means 26 (FIG. 4). This happens a relatively short time before the cover 14 fully closes onto top support portion 16 and enables the container receiving means 26 to rotate freely and quickly until tip 88 of long arm 80 reaches the stopper (not shown). This rotation causes "snap" rotation of the coil 130, i.e. rotation of a relatively short duration and at a relatively high velocity.
Due to the coil's tendency to assume its at-rest state, in which its diameter is less than that of the container, the rotating end of the coil and the container receiving means 26 which is engaged therewith, and is now free to rotate, then rotate in the direction of the arrow 106 at a relatively high angular velocity over a short distance. As a result, the coil-container engagement rapidly tightens until at a certain point (when the bottom turn of the coil engages the container sufficiently tightly), the container begins rotating in the same direction as the rotating end of the coil, thereby enhancing the inertia of the rotation. When the rotation ceases, the coil-beverage container engagement is very tight, thereby enhancing efficient cooling of the beverage by the coil. The spring 46 acts to maintain the tightness of the engagement since relaxation of the engagement (rotation in a direction opposite to arrow 106) results in tensioning of the spring 46 due to the pivoting of elongate element 58.
A further advantage of the tight coil-beverage container engagement provided by the above structure is that it, since there is generally good contact between the coil and the container, the temperature of the coil is an approximate but relatively accurate indication of the temperature of the container. This enables the indication of the temperature of the container to be obtained, without tampering with the container, via sensing the temperature of the coil as shown and described hereinbelow.
The closed orientation of the apparatus is shown in FIG. 1C. When desired (or in response to a suitable signal indicating that the cooling process has been terminated), the user opens the cover 14. The cover engaging element 70 urges the second elongate element 58 to pivot back to its original position. Second elongate element 58 urges the container receiving means 26 and consequently the rotating end of the coil to rotate in the opposite direction to the arrow 106. The second elongate element 58 also tensions the spring 46, which urges the first elongate element 40 back upwards to its original position. The container elevating portion 48 of element 40 causes elevation of the can so that, when the cover 14 is fully open, the user can easily remove the beverage container from the cylindrical volume 12.
The hollow spiral coil element 130 through which refrigerating fluid may flow has a generally nonuniform configuration, which has the advantage of causing the turns of the coil to tighten around the can in a predetermined order.
The cooling apparatus shown and described herein may be actuated in any desired manner. According to a preferred embodiment, there is provided a switch 120 on the support board 20 of the device which is automatically actuated by a protrusion 122 formed on elongate element 40, the protrusion being configured and arranged to contact the switch 120 and transfer it to its "on" position only when the cover 14 has been closed and a container is positioned within the container receiving means 26.
FIGS. 5A and 5B illustrate a first preferred configuration of the hollow spiral coil element 130 in which the spiral coil element 130 is configured such that, at least when no beverage container is engaged therewith, the inner diameters of the turns thereof are non-equal, as seen best in FIG. 5A. A preferred configuration is a truncated conical configuration. It is preferred that, as shown in FIG. 5A, the diameters of the turns gradually increase when proceeding from a rotating end 132 of the spiral coil element to a fixed end 134 thereof. If this configuration is employed, the extreme turn at the rotating end will tighten first, urging the container to rotate, and the turns proceeding from the rotating end to the fixed end will then tighten one at a time. An alternative configuration is an "hourglass" configuration in which the diameters of the turns are greatest at both ends of the coil element and are smallest at the middle of the coil element, in which case the tightening process will begin in the middle of the coil and spread to both ends thereof. Either of these configurations will result in a tight engagement of the coil element 130 with a beverage container and will prevent a situation wherein first and second non-adjacent turns of the coil element tightly engage the container and the turns between the first and second tightly engaged turns are only loosely engaged with the container.
It is noted that when the beverage cooling device is constructed as shown and described hereinabove, i.e. wherein the diameter of the coil at the rotating end thereof is relatively small and increases generally uniformly toward the fixed end of the coil, then almost for the entire time of rotation, the beverage container as well as the rotating end 132 of the hollow coil element 130 is rotated about the axis of the hollow coil element. This construction has the advantage of further tightening the final engagement between the container and the coil element, relative to an alternative construction in which the beverage container does not rotate but rather remains stationary. This is due to the fact that the frictional engagement between the container and the turn that is tightening around the coil at a given moment increases the tension of the portion of the coil defined by the turn. This increase urges the container and the free end of the coil to rotate further, which in turn further increases the frictional forces, causing further tensioning, and so on, until the coil reaches its maximally tensioned state.
A further advantage of the above construction is that the container and the rotating end of the hollow coil element are caused to rotate at a relatively high angular velocity due to the "snap" mechanism which goes into effect when the cover of the device is closed by a user. This acts to increase the inertia of the rotating elements (particularly of the beverage container due to the relatively large mass thereof), resulting in a further tightening of the final engagement between the container and the coil element relative to an alternative construction in which the angular velocity is smaller, due to the impact created by the rotating elements when rotation is terminated due to the coil having reached its maximally tensioned state.
FIG. 9 illustrates the truncated conical configuration of coil 130 wherein the inner diameter ID 1 at the fixed end 134 is larger than the inner diameter ID 2 at the rotating end 132. In FIG. 9, the moments of inertia of the cross sections of the hollow element defining the coil are shown to increase as one proceeds from the fixed end of the coil to the rotating end thereof. The width of the cross section at the fixed end 134 may be approximately b=4.8 mm and the width of the cross section at the rotating end 132 may be approximately a=5 mm, as shown. This configuration enables a truncated conical configuration wherein the inner walls 133 of each coil remains vertical and also results in tightening occurring starting from the rotating end 132 and proceeding toward the fixed end 134. It is appreciated that the moments of inertia of the cross sections of the hollow element defining the coil may be varied in any other suitable manner.
Reference is now made to FIGS. 6A-8C which illustrate cooling control systems useful in conjunction with the coil apparatus shown and described hereinabove and constructed and operative in accordance with various preferred embodiments of the present invention. The cooling is provided by the airconditioning system of the vehicle in which the beverage cooling apparatus is installed.
It has been found that due to the fast heat transfer rate between the coil and the beverage container, a cooling temperature of generally less than about -10 degrees Celsius on the coil 130 for a number of minutes generally causes a thin layer of ice to form inside the container. For gaseous liquids, such as carbonated beverages, the layer of ice causes an increase in the pressure in the container such that a forceable ejection of the liquid occurs when the container is opened. Furthermore, for certain beverages, and particularly dietetic beverages, a temperature of below -7 degrees Celsius on the coil for a number of minutes will generally cause the forceable ejection. Therefore, it is desirable to ensure that the temperature on the coil should not fall below -7 degrees Celsius.
In certain vehicles, particularly vehicles manufactured by American companies such as Chevrolet, Oldsmobile, General Motors, etc., the air conditioning system is such that the temperature on a coil installed in such a vehicle will remain above -7 degrees Celsius. These airconditioners are equipped with a CPS (cycling pressure switch) which maintains the pressure at approximately 25-45 psi, which is equivalent to a temperature of approximately -3 to +8 degrees Celsius. However, even in these vehicles it is preferable to provide a thermostat for ensuring that the temperature on the coil does not drop below -7 degrees Celsius since the CPS can sometimes break down.
Reference is now made to FIGS. 6A-6B, which illustrate a cooling control system suitable for use in vehicles in which the temperature on the coil does not normally fall below -7 degrees Celsius. In FIG. 6A (and in FIGS. 7A, 8A and 8C), the double lines indicate the flow of refrigerant fluid whereas the single lines indicate associations between the control components.
The airconditioning system of the vehicle normally comprises the following elements interconnected in the standard manner: a drier 250, a condensor 252, a compressor 210 having an associated clutch 230, a thermostat 217 controlling the compressor 210 and having a temperature sensor 254, the sensor 254 being in temperature sensing association with an evaporator 256, and an expansion valve 258. The fluid cooling system of the present invention comprises an additional path for refrigerant fluid located across the drier, condensor and compressor. Along the path there are provided the coil 130, a capillary 260 and an electric valve 218. The coil 130 has a first end 208 and a second end 212, the second end 212 being that connected to the capillary 260. A temperature sensor 214 is provided in temperature sensing association with the end 212 of the coil. It is appreciated that the temperature at end 212 of the coil will generally be lower than or at least as low as the temperature at end 208 of the coil.
Input from the sensor 214 is received by a thermostat 216 which controls the electric valve 218. Valve 218 controls the supply of refrigerating fluid from the compressor 210 to the coil 130. Thermostat 216 is suitably programmed in order to substantially prevent too rigorous cooling of the container and consequent forceable ejection of the beverage from the container when opened. For example, thermostat 216 may be programmed such that cooling of the coil stops when the temperature sensed by sensor 214 drops to -7 degrees Celsius and is renewed when the temperature sensed by the sensor 214 reaches -6 degrees Celsius.
It is noted that the embodiment of FIGS. 6A-6B operates externally of the control components of the airconditioning system and is not intrusive thereinto.
Reference is now made to FIGS. 7A-7C, which illustrate a cooling control system suitable for use in vehicles in which the temperature on the coil, in the course of normal operation of the airconditioning system, sometimes falls below -7 degrees Celsius. Identical reference numbers to the reference numbers of FIG. 6A will be used herein to denote elements similar to those of FIG. 6A.
The embodiment of FIG. 7A is generally similar to the embodiment of FIG. 6A. However, no valve 218 is provided and thermostat 216, instead of controlling valve 218, directly controls the clutch 230 of the compressor 210. Thermostat 216 is suitably programmed in order to substantially prevent too rigorous cooling of the container and consequent forceable ejection of the beverage from the container when opened. For example, the thermostat 216 may be programmed such that operation of the compressor is terminated when the temperature sensed by sensor 214 drops to -7 degrees Celsius and is renewed when the temperature sensed by the sensor 214 reaches +1 degrees Celsius.
In FIG. 7B, the thermostat 216 is shown connected in series with the integral thermostat 217 of the vehicle's airconditioning system. In FIG. 7C, the thermostat 216 is connected across the thermostat 217, and the actuating switch 120 is operative to ensure that the vehicle's integral thermostat 217 is rendered inoperative during the operation of the cooling system shown and described herein, the operation of the compressor being entirely controlled by the thermostat 216. This has the advantage of preventing cessation of cooling due to cessation of the operation of the compressor by the thermostat 217.
Reference is now made to FIGS. 8A-8B, which illustrate a cooling control system suitable for use in vehicles in which the temperature on the coil, in the course of normal operation of the airconditioning system, sometimes falls below -7 degrees Celsius. The embodiment illustrated resembles the embodiment of FIGS. 6A-6B except for the following differences: both ends of the coil are connected to thermostats via temperature sensors, instead of only one end of the coil as in FIGS. 6A-6B. As in FIGS. 6A-6B, sensor 214 is in temperature sensing association with end 212 of the coil and the data therefrom is received by thermostat 216. In addition, a sensor 242 is provided in temperature sensing association with end 208 of the coil and the data therefrom is received by a thermostat 244. Thermostats 244 and 216 control the operation of electric valve 218 which controls the flow of refrigerant fluid from the compressor 210 to the coil. Thermostat 244 is operative to ensure that the temperature range sensed by temperature sensor 242 remains within the range of 0 to -7 degrees Celsius, whereas thermostat 216 is operative to ensure that the temperature range sensed by temperature sensor 214 remains within the range of 0 to -18 degrees Celsius: If the low point of either temperature range is sensed, the valve 218 cuts off the flow of refrigerant fluid, renewing it if the high point of either temperature range is sensed.
In FIG. 8B, there is shown an optionally provided timer 240 which gives an indirect indication of the temperature of the fluid in the container. Specifically, the timer 240 counts the time interval in which thermostat 244 is in its disconnected state. If the temperature is found to go from -7 degrees to 0 degrees in a relatively short time period, e.g. within 15 seconds, this indicates that the fluid is insufficiently cool and the cooling process is not terminated. If the temperature is not found to reach 0 degrees within 15 seconds, this indicates that the fluid is cool enough and the cooling process is terminated. Preferably, audio indicating means (not shown) indicates this to the user of the device.
Reference is now made to the embodiment of FIG. 8C, which is a proposed variation of the embodiment of FIG. 8A, being generally similar thereto except that the inputs from sensors 214 and 242 are received by a microprocessor 246, instead of being separately received by thermostats 216 and 244. The microprocessor controls valve 218. Microprocessor 246 is suitably programmed to ensure that the temperatures sensed by thermostats 244 and 216 do not fall below -18 degrees Celsius, by cutting off the flow of refrigerant fluid at that point. Also, microprocessor 246 terminates cooling when the difference of temperature sensed by sensor 242 and by sensor 214 is less than 2 degrees Celsius, or after 8 minutes of cooling have elapsed, whichever of the two time periods is shorter.
It is noted that the embodiments of FIGS. 8A and 8C operate externally to the control components of the airconditioning system and are not intrusive thereinto.
It is noted that all specifications hereinabove of parameters of time and temperature for the various embodiments of the cooling control systems disclosed hereinabove are approximations of the true values which may vary as a function of the equipment, the beverage to be cooled, the airconditioning system, and other factors.
In the cooling control systems described hereinabove, any suitable temperature sensors may be employed, such as the IT 5001, commercially available from Dale, El Paso, Tex. Any suitable electric valves may be employed, such as the in-line valve commercially available from Bakara, Kibbutz Geva, Israel. The coil may be formed of any suitable material, such as copper.
It will be appreciated by persons skilled in the art, that the present invention is not limited by what has been particularly shown and described above. The scope of the invention is limited, rather, solely by the claims which follow:
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A system for cooling fluid stored in a generally cylindrical container is disclosed. The system includes a generally cylindrical hollow coil element having an engaged orientation for engaging the container and at least one disengaged orientation in which the container is disengaged. The hollow coil element is configured to provide thermal engagement between a refrigerant fluid located interiorly thereof and the container when the hollow coil element is in the engaged orientation. The hollow coil element includes at least one elongate hollow element with a nonuniform generally spiral configuration, wherein the spiral defines a plurality of turns of the elongate hollow element. There is also disclosed a system for cooling gaseous fluid stored in a selectably disengageable container. The system includes receiving apparatus for selectably receiving the container, cooling apparatus for providing a refrigerant fluid in thermal engagement with the container and apparatus for substantially preventing forceable egress of the gaseous fluid from the container when the container is opened.
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BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a control system having a control computer, which is intended to interchange data with at least one peripheral, and at least one further control computer which is connected to the control computer via a communication channel and is designed to assume at least part of the functionality of the control computer.
Such a control system is known, for example, from the published international patent application WO 02/01305 A1. Said application describes a redundant control system in which a peripheral is connected both to a first control computer and to a second control computer. The two control computers synchronously execute the same control program, in which case a communication channel in the form of a redundant coupling is provided in order to synchronize said computers. If the control system detects failure of one of the two control computers, the system changes over to the other control computer which then interchanges data directly with the peripheral.
BRIEF SUMMARY OF THE INVENTION
The present invention is based on the object of specifying a particularly simple and, at the same time, fail-safe control system.
According to the invention, this object is achieved by a control system of the type mentioned at the outset, in which the control computer is designed, in the event of its partial failure, to forward data received from the further control computer via the communication channel to the peripheral and/or to forward data received from the peripheral to the further control computer via the communication channel.
The control system according to the invention affords the advantage that it is possible to dispense with a redundant design of the control computer. This is enabled by virtue of the fact that the control computer is designed in such a manner that, even in the event of its partial failure, it can at least still be used to forward the data. This makes it possible for the further control computer to assume the functionality, that is to say the processing function, of the failed control computer without the need for the peripheral(s) to be directly connected to the further control computer. This advantageously dispenses with the need for the peripheral(s) to be correspondingly connected to a plurality of control computers.
Redundant control systems are known, for example, as so-called 2×2v2 systems in which 2 independent reliable 2v2 systems, that is to say two separate two-channel systems in each case, are used. In comparison with this, the control system according to the invention requires fewer components, thus saving effort and costs. At the same time, however, the failure safety of the control system remains substantially unaffected by this.
The control system according to the invention is preferably developed in such a manner that at least one further peripheral is associated with the further control computer, and the further control computer is intended to interchange further data with the further peripheral. This affords the advantage that the further control computer itself can be used to interchange data with at least one further peripheral and to control at least one further peripheral. This means that, in the event of partial failure of the control computer, the further control computer assumes the functionality of the control computer or at least part of this functionality in addition to its actual tasks. This has the advantage that there is no need for an additional control computer in order to interchange the further data with the at least one further peripheral.
In principle, the control computer can be a computer with any desired architecture and any desired design. This includes, for example, any desired hardware configurations and operating systems. In another particularly preferred embodiment of the control system according to the invention, the control computer is a multi-channel reliable computer. This affords the advantage that, if a channel in a 2v2 computer fails for example, the channel which has not failed admittedly can no longer alone ensure reliable processing, but this channel can nevertheless still be used to forward, that is to say to route, data. The peripheral(s) connected to the control computer is/are actually controlled in this case using the further control computer which has not failed and is preferably likewise a multi-channel reliable computer.
In one preferred embodiment, the control system according to the invention is configured in such a manner that it is designed to transmit the data forwarded by the control computer from the further control computer to the peripheral and/or to transmit the data forwarded by the control computer from the peripheral to the further control computer in a manner protected against corruption. This is advantageous since it makes it possible to check the integrity of the transmitted data for safety-relevant applications. If, for example, a channel in the control computer has failed, it is not possible to preclude that the remaining channel which has not failed and is now used exclusively to forward or pass the data possibly corrupts the data forwarded by it on account of an additional undiscovered failure. Said preferred embodiment of the control system according to the invention now makes it possible for the peripheral and/or the further control computer to detect corresponding corruption and to initiate corresponding measures, for instance in the form of rejecting the transmitted data, repeating the transmission of the data and/or outputting a fault signal. The corruption can be detected, for example, by evaluating a signature, for instance in the form of a hash value, for the transmitted data.
The control system according to the invention can preferably also be designed in such a manner that the control computer is designed to assume at least part of the functionality of the further control computer, and the further control computer is designed, in the event of its partial failure, to forward data received from the control computer via the communication channel to the further peripheral and/or to forward data received from the further peripheral to the control computer via the communication channel. This affords the advantage that, in the event of partial failure of the further control computer, data transmission and control are enabled using the control computer. This means that the control computer and the further control computer can reciprocally assume the functionality or processing function of the respective other control computer. As an alternative to this, it is also conceivable, for example, for an additional control computer, rather than the control computer, to be designed to assume the functionality of the further control computer. This means that, if a control computer fails in a control system having networked control computers, the function of said control computer can, in principle, be assumed entirely or else partially by one of the other control computers. In this case, it is also conceivable, in particular, for a plurality of control computers to together assume the processing function of a failed control computer. In this case, it is necessary for the failed control computer to be designed to forward the data to or from the plurality of control computers.
In another particularly preferred embodiment of the control system according to the invention, the peripheral is a sensor or an actuator. This is advantageous since failure safety is very important, in particular, when controlling such peripherals. In addition, it is often desirable for sensors or actuators to have to be connected to only one control computer rather than having to be additionally connected to a further control computer for redundancy reasons.
The control system according to the invention may, in principle, be part of any desired superordinate system. In one particularly preferred development, the control system is part of a railroad protection technology system or automation technology system. This is advantageous since corresponding systems impose particularly high demands on failure safety and generally connect a multiplicity of peripherals to control computers. In the case of a railroad protection technology system, corresponding peripherals may be, for example, a points contact, a signal, a points drive or an actuator, and, in the case of an automation technology system, corresponding peripherals may be, for example, process control sensors or actuators in a factory.
The invention also relates to a control computer for a control system having a control computer, which is intended to interchange data with at least one peripheral, and at least one further control computer which is connected to the control computer via a communication channel and is designed to assume at least part of the functionality of the control computer.
With regard to the control computer, the present invention is based on the object of specifying a control computer which enables a particularly simple and, at the same time, fail-safe design of the control system.
For a control computer of the type mentioned above, this object is achieved, according to the invention, by the fact that the control computer is designed, in the event of its partial failure, to forward data received from the further control computer via the communication channel to the peripheral and/or to forward data received from the peripheral to the further control computer via the communication channel.
The advantages of the control computer according to the invention substantially correspond to the advantages mentioned above in connection with the control system according to the invention. The control computer according to the invention thus affords the advantage, in particular, that it is possible to dispense with a redundant design for the purpose of failure safety.
In one preferred development of the control computer according to the invention, the control computer is a multi-channel reliable computer. In accordance with the above explanations of the corresponding embodiment of the control system according to the invention, this affords the advantage that, if one of the channels in the reliable computer fails, a further channel or the further channel in the reliable computer is available for forwarding the data from or to the further computer.
The control computer according to the invention is preferably configured in such a manner that it is designed to assume the functionality of the further control computer. This affords the advantage that the control computer can additionally be used for failure protection of the further control computer.
In addition, the invention relates to a method for operating a control system having a control computer, which is intended to interchange data with at least one peripheral, and a further control computer which is connected to the control computer via a communication channel and is designed to assume at least part of the functionality of the control computer.
With regard to the method, the present invention is based on the object of specifying a particularly simple and, at the same time, fail-safe method for operating a control system.
For a method of the type mentioned above, this object is achieved, according to the invention, by virtue of the fact that the control computer, in the event of its partial failure, forwards data received from the further control computer via the communication channel to the peripheral and/or forwards data received from the peripheral to the further control computer via the communication channel.
With regard to the advantages of the method according to the invention, reference is made to the advantages mentioned in connection with the control system according to the invention and the control computer according to the invention.
The method according to the invention is advantageously developed in such a manner that the data forwarded by the control computer from the further control computer to the peripheral and/or the data forwarded by the control computer from the peripheral to the further control computer are transmitted in a manner protected against corruption. This prevents undetected corruption of the transmitted data, in particular by the failed control computer being used for forwarding.
The invention is explained in more detail below using exemplary embodiments. In this respect
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
FIG. 1 shows an exemplary embodiment of the control system according to the invention in the fault-free state, and
FIG. 2 shows the exemplary embodiment of the control system according to the invention from FIG. 1 in a state in which one of the control computers has at least partially failed.
DESCRIPTION OF THE INVENTION
FIG. 1 shows an exemplary embodiment of the control system according to the invention in the fault-free state. In detail, a control system having a control computer 1 and a further control computer 2 is shown. The control computer 1 and the further control computer 2 are connected to one another via a communication channel 3 . In this case, the communication channel 3 may be of any desired type (wireless or wired), with the result that the control computer 1 and the further control computer 2 can be arranged at any desired distance from one another, for example.
In the exemplary embodiment in FIG. 1 , both the control computer 1 and the further control computer 2 are in the form of a two-channel reliable computer, that is to say in the form of a 2v2 system. This means that the control computer 1 has a first channel 1 a and a second channel 1 b . The same applies to the further control computer with respect to the two channels 2 a and 2 b . It is pointed out that the channels 1 a , 1 b , 2 a , 2 b may also be independent components, for instance in the form of a respective PC (personal computer), which form the respective control computer 1 or 2 together with further components.
In the exemplary embodiment in FIG. 1 , the channels 1 a , 1 b , 2 a , 2 b each have both a processing function 4 a , 4 b for the functionality of the control computer 1 and a further processing function 5 a , 5 b for the functionality of the further control computer 2 . In this case, in the state which is illustrated in FIG. 1 and in which there is no failure, the processing function of the respective other control computer 1 , 2 is inactive in the respective control computer 1 , 2 . This means that only the processing function 4 a , 4 b for the control computer 1 is active in the control computer 1 and only the processing function 5 a , 5 b for the further control computer 2 is active in the further control computer 2 .
The processing functions 4 a , 4 b each run simultaneously and in a parallel manner in the two channels 1 a , 1 b in the control computer 1 ; a corresponding situation applies to the processing functions 5 a , 5 b of the further control computer 2 with respect to the channels 2 a , 2 b in the further control computer 2 . In order to protect against malfunctions of the individual channels 1 a , 1 b or 2 a , 2 b , the processing results from the two channels 1 a , 1 b or 2 a , 2 b are respectively compared in this case by a comparison device (not illustrated in FIG. 1 for reasons of clarity) in the respective control computer 1 , 2 .
In addition, the control computer 1 and the further control computer 2 each comprise a functionality 6 a , 6 b for forwarding data respectively received from the other control computer 2 or 1 . However, this functionality 6 a , 6 b is inactive in the normal fault-free state shown in FIG. 1 . This means that, in the normal state of the control system, data are interchanged with peripherals 10 a , 10 b , 10 c , 10 d , 10 e solely by the control computer 1 and data are interchanged with further peripherals 11 a , 11 b , 11 c , 11 d , 11 e solely by the further control computer 2 .
If the control system is, for example, a railroad protection technology system, the peripheral 10 a may be, for example, a reliable input/output system, the peripheral 10 b may be a points contact, the peripheral 10 c may be an actuator in the form of a signal, the peripheral 10 d may be a sensor and the peripheral 10 e may be an actuator in the form of a points drive. The peripherals 10 a , 10 b , 10 c , 10 d , 10 e and the further peripherals 11 a , 11 b , 11 c , 11 d , 11 e are advantageously connected to the control computer 1 and to the further control computer 2 , respectively, in such a manner that the data are transmitted in a manner protected against corruption.
FIG. 2 is used below to explain how the control system behaves in the event of partial failure of the control computer 1 .
FIG. 2 shows the exemplary embodiment of the control system according to the invention from FIG. 1 in a state in which one of the control computers has at least partially failed. In this case, components which are unchanged with respect to FIG. 1 are denoted using the same reference symbols in each case.
In contrast to FIG. 1 , FIG. 2 illustrates a state of the control system in which the channel 1 a in the control computer 1 has failed. Since it is no longer possible to reliably interchange data between the control computer 1 and the peripherals 10 a to 10 e , the control computer 1 forwards data received from the peripherals 10 a , 10 b , 10 c , 10 d , 10 e to the further control computer 2 via the communication channel 3 . At the same time, the processing function 4 a , 4 b of the control computer 1 is activated in the further control computer 2 . Corresponding activation can be effected, for example, using a signal from that channel 1 b in the control computer 1 which has not failed, which signal is received via the communication channel 3 .
Furthermore, on account of the fact that the failure of the channel 1 a in the control computer 1 has been detected, the forwarding functionality 6 b of the channel 1 b is activated. In addition, the processing functions 4 b , 5 b of that channel 1 b in the control computer 1 which has not failed are switched off since they are now no longer used.
As a result, data transmitted to the peripherals 10 a , 10 b , 10 c , 10 d , 10 e , that is to say actuating commands for an actuator for example, are passed through to the relevant peripheral 10 a , 10 b , 10 c , 10 d , 10 e by that channel 1 b in the control computer 1 which has not failed. In this case, as already stated above, the peripherals 10 a , 10 b , 10 c , 10 d , 10 e are advantageously connected to the control computer 1 via a reliable input/output system. Data transmitted from the peripherals 10 a , 10 b , 10 c , 10 d , 10 e , that is to say from sensors for example, to the control computer 1 are likewise forwarded by the forwarding function 6 b , that is to say the routing functionality, of the control computer 1 to the further control computer 2 for further, reliable or protected processing.
The processing function 5 a , 5 b of the further control computer 2 is affected by the further control computer 2 assuming the processing function 4 a , 4 b of the control computer 1 only insofar as the further control computer 2 must provide the power for all of the processing functions 4 a , 4 b , 5 a , 5 b . In this case, it is necessary for the communication channel 3 to be designed in such a manner that it is able to transmit the data which have been forwarded or need to be forwarded. The time delay resulting from the forwarding of the data should be designed for the properties of the processes, for example of railroad protection technology, connected to the peripherals 10 a , 10 b , 10 c , 10 d , 10 e in order to avoid the functionality of these processes being impaired.
In accordance with the above statements, the control system illustrated is particularly advantageous in safety-relevant applications when the connected peripherals 10 a , 10 b , 10 c , 10 d , 10 e , that is to say actuator or sensor systems for example, are independently designed to check the actuating commands for the actuators or the coding of the sensor data for corruption. The reason for this is that, in the event of a failed channel 1 a in the control computer 1 , it must be assumed that the remaining channel 1 b which thus has not failed and is now exclusively used to forward the data could possibly corrupt the forwarded data on account of a further undiscovered failure.
In accordance with the above statements, the control system described has the advantage, in particular, that it is possible to dispense with a redundant design of the individual control computers 1 , 2 . This is made possible by networking the control computers 1 , 2 by means of the communication channel 3 and using the failed control computer 1 to forward data between the further control computer 2 , which assumes the functionality of the control computer, and the peripherals 10 a , 10 b , 10 c , 10 d , 10 e . In this case, the control computer 1 can use, for example, a remaining functional channel 1 b in the control computer 1 to forward the data.
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A particularly simple and simultaneously fail-safe control system has a control computer for interchanging data with at least one peripheral, and at least one further control computer connected to the first-mentioned control computer via a communication channel. The further control computer is configured to assume at least part of the functionality of the control computer. The control computer is designed, in the event of partial failure thereof, to forward data received by the further control computer via the communication channel to the peripheral and/or to forward data received by the peripheral to the further control computer via the communication channel. There is also provided such a control computer and a method for operating a control system.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to collaboration suite applications, and more particularly, to collaboration suite functionality in a client-server architecture.
2. Description of the Related Art
Collaboration suite applications typically include functionality such as email messaging, calendaring, and contact storage and retrieval, where email messages, calendar appointments, contacts, tasks, folders, documents, files, etc. are commonly referred to as “mailbox items.” The ZIMBRA COLLABORATION SUITE® from Zimbra, Inc. (San Mateo, Calif.), MICROSOFT EXCHANGE® and MICROSOFT OUTLOOK® from Microsoft Corp. (Redmond, Wash.), LOTUS NOTES® from IBM (Armonk, N.Y.) are examples of collaboration suite applications. YAHOO! MAIL® from Yahoo! Inc. (Sunnyvale, Calif.) and GMAIL® from Google Inc. (Menlo Park, Calif.) are e-mail applications which are also part of collaboration suites.
A collaboration suite application sometimes has a client-server architecture, where the client portion resides on a user device. The user device can include a personal computer, a MAC® computer, various handheld devices including personal digital assistants (PDAs) such as a TREO® device from Palm, Inc. (Sunnyvale, Calif.) a BLACKBERRY® device from Research In Motion Limited (Canada), a cell phone, and so on. It is to be noted that this list is in no way meant to be exhaustive.
As an example, the BLACKBERRY® device is discussed below in further detail. The BLACKBERRY® device is a wireless handheld device which includes the usual collaboration suite applications such as email, calendaring, contacts, to-do lists, etc. BLACKBERRY® devices are very popular with some businesses, where they are primarily used to provide e-mail access to roaming employees. To fully integrate the BLACKBERRY® device into a company's systems, the installation of BLACKBERRY ENTERPRISE SERVER® (BES) is required. FIG. 1 shows a BES machine 100 , which is a client to the MICROSOFT EXCHANGE SERVER® 110 . The BES machine 100 includes the BES 130 which uses MICROSOFT® Messaging API (MAPI) 125 . The MICROSOFT EXCHANGE® MAPI Provider 120 also resides on the BES machine 100 , and is used to communicate bidirectionally with the Microsoft Exchange Server MICROSOFT EXCHANGE SERVER® via a network 150 . The BES machine 100 is typically deployed and managed within the enterprise by messaging administrators (for example, the individuals already responsible for managing MICROSOFT EXCHANGE®) or sometimes a dedicated IT person, usually called the BLACKBERRY® or BES Administrator. It is to be noted that the architecture described with respect to FIG. 1 may be equally applicable to other collaboration suite servers (e.g., LOTUS DOMINO® Servers from IBM (Armonk, N.Y.), GROUPWISE® from Novell (Waltham, Mass.), etc.).
BES 130 can act as a sort of e-mail relay for corporate accounts so that users always have access to their mailbox items. The software monitors the mailbox on the MICROSOFT EXCHANGE SERVER® 110 via MAPI 120 , and when a new message comes in, it picks up the message and the messages are then relayed to the user's wireless provider (not shown in FIG. 1 ), which in turn delivers them to the user's BLACKBERRY® device (not shown in FIG. 1 ).
In such a scenario, the MICROSOFT EXCHANGE SERVER® 110 experiences additional load because all of the operations that the BES 130 conducts (e.g., those requested by the user) are conducted off the collaboration suite server 110 . Additional load is generated by any read or search operation. Examples of such operations include the user device fetching attachment content, the device executing searches or filters on the collaboration server, the device fetching large message bodies, the device needing to resynchronize its contents, and so on.
It is to be noted that the BES's 130 responsibility for synchronizing multiple mailboxes and devices (not shown) aggravates the problems discussed above.
A cache mode, where a local cache of your mailbox is stored (e.g., on a user device) is available for some programs. For instance, in MICROSOFT OUTLOOK 2003®, cached mode is a mechanism that keeps users' MICROSOFT EXCHANGE SERVER® mailboxes synchronized with offline folders that reside on their local hard disks. When MICROSOFT OUTLOOK® is used with a MICROSOFT EXCHANGE SERVER® 110 e-mail account, a copy of the user's mailbox is stored on the user's computer. This copy provides quick access to data and is frequently updated with the mail server. This provides for a better user experience. If the user works offline, whether by choice or due to a connection problem, his data is still available to him instantly wherever he is, even if a connection from the user's computer to the computer running Exchange server isn't available.
There are several limitations on such existing cache modes. For one thing, a cache mode is not available for scenarios where the mailboxes of multiple users need to be synchronized (e.g., using BES). In particular, the need to synchronize multiple mailboxes and devices leads to the need for the more efficient and scalable cached mode requirement. Not having a cache mode leads, as discussed above, to an increased load on the collaboration suite server. It also leads to a less reliable user experience. Moreover, even in cases where the cached mode does exist, as the size of a user's mailbox gets large, the large size of the caches can lead to disk capacity and performance issues. Further, the size of the user's mailbox is relevant in some cases (e.g. MICROSOFT OUTLOOK®) because an .OST file is often used to store cached data. Performance of an .OST file degrades significantly as mailbox size grows, especially with multi-gigabyte mailboxes. Moreover, for existing cache modes, the initial synchronization between the caches and the Collaboration Suite Server puts a significant load on network bandwidth and on the Collaboration Suite Server. For instance, with MICROSOFT OUTLOOK® cache mode, during the initial synchronization, all pre-existing MICROSOFT EXCHANGE® data has to be copied from the MICROSOFT EXCHANGE SERVER® to the .OST file being used for a user's cache. Further, there is no seamless periodic deletion of mailbox items across various folders, unless the user sets such filters for each folder individually. Moreover, there is no ability to get an individual mailbox item “on-demand” from the server if it is not stored on the cache.
There is thus a need for a cached mode for some applications to manage the load on the collaboration suite server. Further, there is a need for an efficient and scalable cached mode for synchronizing multiple mailboxes for multiple users of a collaboration suite application with their user devices. Further still, there is a need to manage the initial synchronization between the collaboration suite server and the cache. Moreover, there is a need for the ability to reap simply and easily across the user's mailbox. Furthermore, there is a need to obtain on demand mailbox items which are not in the cache.
BRIEF SUMMARY OF THE INVENTION
According to one aspect of the present invention, a cached mode is created for some applications (e.g., for use with the BES) to manage the load on the collaboration suite server in a multi-user scenario. Operations on the mailbox items are conducted off the cache, rather than off the collaboration suite server itself, thus reducing the load on the collaboration suite server.
In accordance with an embodiment of the present invention, a more efficient cache mode is created for collaboration suite applications. In accordance with an embodiment of the present invention, an efficient and scalable cached mode provides for synchronization of multiple mailboxes of multiple users of a collaboration suite application with their multiple user devices.
According to one aspect of the present invention, a filtered initial synchronization is performed with a local cache. In one embodiment, the cache is on the client device. In one embodiment, the client device is a mobile device (e.g., a BLACKBERRY® device). In one embodiment, the client device is user's host computer (e.g., a PC, a MAC®, a laptop, etc.). In another embodiment, the local cache is on a synchronization server, which synchronizes data for multiple users' mailboxes. The filtered initial synchronization is based on filters regarding to factors such as how many days worth of data should be downloaded etc. Such a filtered initial synchronization avoids use of large amounts of disk space in the client device (which would occur by simply transferring all the data from the collaboration suite server into the local cache). Further, such a filtered initial synchronization reduces the required bandwidth as well as the load on the collaboration suite server.
In one embodiment, this filtered initial synchronization is non-blocking. That is, new mailbox items received by the collaboration suite server are added to the cache even while the initial synchronization (filtered or non-filtered, depending on the embodiment) is ongoing. In one embodiment, a secondary synchronizer is used for this purpose.
Once the initial filtered synchronization is done, data is synchronized in real-time between the user's mailbox on the collaboration suite server and the cache.
In one embodiment of the present invention, mailbox items on the local cache are periodically reaped so as to not over-burden the disk space in the client device. In one embodiment, such reaping includes periodically removing data that is older than a predetermined time-period. This time-period can be determined, in one embodiment, by a system administrator. In one embodiment, this time-period can be determined by a user. For instance, in one embodiment, emails that have been received more than 7 days ago are deleted from the cache. In one embodiment, the reaped information is not removed from the collaboration suite server, but rather only from the cache. Thus the user can, in one embodiment, access a mailbox item on-demand from the collaboration suite server, even if it has been reaped from the cache. Hence the reaping is transparent to the user in that the user can access a mailbox item regardless of whether or not that mailbox item has been reaped from the cache. The user can have seamless access to a superset of the data in the cache. Such reaping is, in accordance with an embodiment of the present invention, transparent to the synchronization server.
The features and advantages described in this summary and the following detailed description are not all-inclusive, and particularly, many additional features and advantages will be apparent to one of ordinary skill in the art in view of the drawings, specification, and claims hereof. Moreover, it should be noted that the language used in the specification has been principally selected for readability and instructional purposes, and may not have been selected to delineate or circumscribe the inventive subject matter, resort to the claims being necessary to determine such inventive subject matter.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention has other advantages and features which will be more readily apparent from the following detailed description of the invention and the appended claims, when taken in conjunction with the accompanying drawing, in which:
FIG. 1 is a block diagram of a prior art system showing a MICROSOFT EXCHANGE SERVER® and a BES.
FIG. 2 is a block diagram of a system in accordance with an embodiment of the present invention,
FIG. 3 is a block diagram of a collaboration suite synchronization client for a system with multiple users of a collaboration suite application in accordance with an embodiment of the present invention.
FIG. 4 is a flowchart which outlines some of the steps taken by a system in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The figures (or drawings) depict a preferred embodiment of the present invention for purposes of illustration only. It is noted that similar or like reference numbers in the figures may indicate similar or like functionality. One of skill in the art will readily recognize from the following discussion that alternative embodiments of the structures and methods disclosed herein may be employed without departing from the principles of the invention(s) herein. It is to be noted that while some portions of the following discussion focus on the BLACKBERRY® device and the BES, the present invention is in no way limited to these.
FIG. 2 is a block diagram of a system in accordance with an embodiment of the present invention. The block diagram includes a user synchronization machine 200 , a collaboration suite server 210 , a synchronization server 220 , and multiple user devices 240 a . . . 240 n.
Collaboration suite applications typically include functionality such as email messaging, calendaring, and contact storage and retrieval, where email messages, calendar appointments, contacts, tasks, folders, documents, files, etc. are commonly referred to as “mailbox items.” The ZIMBRA COLLABORATION SUITE® from Zimbra, Inc. (San Mateo, Calif.), Microsoft Exchange MICROSOFT EXCHANGE® and Microsoft Outlook MICROSOFT OUTLOOK® from Microsoft Corp. (Redmond, Wash.), LOTUS NOTES® from IBM (Armonk, N.Y.) are examples of collaboration suite applications. The collaboration suite server 210 has a data store 215 , which stores mailbox items for each of the multiple users of the system. In one embodiment, the collaboration suite application has a client/server architecture, and the collaboration suite server 210 is the server in such a situation.
In one embodiment, a collaboration suite sync client 220 is the client which communicates with the collaboration suite server 210 over a network 250 a . The collaboration suite synchronization client 220 is responsible for synchronizing the data on the collaboration suite server 210 with the different user devices. As can be seen from FIG. 2 , the collaboration suite sync client 220 resides on the user synchronization machine 200 , and communicates via MAPI 225 with the user device synchronization server 230 . (It is to be noted that the user synchronization machine 200 can be split across several physical machines/servers.) The collaboration suite synchronization client 220 is discussed in greater detail below with reference to FIG. 3 .
In one embodiment, the user device synchronization server 230 functions as the server for the collaboration suite client on a user devices 240 a . . . 204 n , which are described in further detail below. The user device synchronization server 230 communicates with the collaboration suite synchronization client 220 using MAPI 225 . The BLACKBERRY ENTERPRISE SERVER® from RIM and the GOODLINK SERVER® from Motorola (Schaumburg, Ill.) are examples of the user device synchronization server 230 .
Network 1 250 a and Network 2 250 b can be any networks, such as a Wide Area Network (WAN) or a Local Area Network (LAN), or any other network, such as a wireless phone network. A WAN may include the Internet, the Internet 2, and the like. A LAN may include an Intranet, which may be a network based on, for example, TCP/IP belonging to an organization accessible only by the organization's members, employees, or others with authorization. A LAN may also be a network such as, for example, Netware™ from Novell Corporation (Provo, Utah) or WINDOWS NT® from Microsoft Corporation (Redmond, Wash.). The network 350 may also include commercially available subscription-based services such as, for example, AOL® from America Online, Inc. (Dulles, Va.) or MSN® from Microsoft Corporation (Redmond, Wash.). In one embodiment, Network 1 250 a and Network 2 250 b are different from each other. For instance, in one embodiment, Network 1 350 a is the Internet, while Network 2 250 b is a wireless phone network. In another embodiment, Network 1 250 a and Network 2 250 b are the same. In one embodiment, Network 1 250 a and/or Network 2 250 b are combinations of two or more different types of networks (e.g., Internet and phone network).
The user devices 240 a - 240 n , in one embodiment, are various handheld devices. These can include personal digital assistants (PDAs) such as a TREO® device from Palm, Inc. (Sunnyvale, Calif.), a BLACKBERRY® device from Research In Motion Limited (Canada), a cell-phone, and so on. The user device can also be a user's desktop or laptop computer (e.g., PC or MAC®). It is to be noted that this list is in no way meant to be exhaustive. Each of the user devices 240 a - n has an instance of the collaboration suite client 270 a - n on it.
FIG. 3 shows the collaboration suite synchronization client 220 in greater detail. It is to be noted that not all the components of the collaboration suite synchronization client 220 are shown here, for ease of understanding and simplicity. Furthermore, not all the connections between the various components included in the figure are shown in FIG. 2 .
The collaboration suite synchronization client 220 includes the collaboration suite MAPI provider 320 , user caches 340 a . . . 340 n (collectively 340 ), a synchronizer 350 , a secondary synchronizer 352 , a real-time notifier 360 , a reaper 370 , an on-demand fetcher 380 , and a MAPI translator 390 .
The user caches 340 a . . . 340 n each correspond to a mailbox. The use of these caches 340 a . . . 340 n for multiple mailboxes reduces the load on the collaboration suite server 210 , as described above. The user devices 240 a . . . 240 n are synchronized with the corresponding user caches 340 a . . . 340 n using the user device synchronization server 230 .
The synchronizer 350 and the secondary synchronizer 352 synchronize the data for a particular user in the data store 215 with the corresponding user cache 340 a . . . n . This is described in further detail with reference to FIG. 4 below.
The synchronizer communicates with the real-time notifier 360 , which communicates with the collaboration suite server 210 , to be notified of any real-time changes to the mailbox (e.g., new mail messages received).
The reaper 370 periodically reaps the various user caches 340 a . . . 340 n so as to not overload the user synchronization machine 200 . Thus mailbox items are systematically removed from user caches 340 a . . . 340 n . For instance, emails older than a certain date (e.g., older than 7 days) are deleted from the local cache 340 a . . . 340 n . In one embodiment, such reaping is transparent to the user in that a user can access any of his/her mailbox items from user device 240 a . . . 240 n , regardless of whether or not it is on the user cache 340 a . . . 340 n . This is done, in one embodiment, by communicating with the on-demand fetcher 390 , which fetches from the data store 215 on the collaboration suite server 210 , any mailbox item requested by a user which has been reaped from the user cache 340 a . . . 340 n . This is described in greater detail below with reference to FIG. 4 .
The MAPI translator 390 translates commands etc. to and from MAPI, prior to communication with the collaboration suite server 210 .
The functionality of the various modules shown in FIG. 3 is described in greater detail below with reference to FIG. 4 .
FIG. 4 is a flowchart which outlines some of the steps taken by a system in accordance with an embodiment of the present invention. An initial filtered synchronization (step 410 ) is performed between the collaboration suite server 210 and the caches 340 . This initial filtered synchronization is discussed further below.
Some or all of the data in the data store 215 for user n needs to be synchronized with the cache 340 n . In accordance with an embodiment of the present invention, the initial synchronization of the user n's data in data store 215 with the cache 340 n is filtered. All of the data for user n in the data store 215 is not synchronized with the cache 340 n . Instead, a subset of the data in the user's mailbox is synchronized with the cache 340 n . In one embodiment, the filters relating to what data should be downloaded onto the cache 340 are set by the user. In one embodiment, such filters are set by a system administrator. The filters can have one or more parameters, such as how old the data is. For instance, data in the user's mailbox that is older than 7 days may not need to be downloaded to the cache 340 . In one embodiment, a filter is applied only to certain types of mailbox items (e.g., emails, calendar entries, etc.), while other types of mailbox items (e.g., contacts, notes, etc.) are not filtered. In one embodiment, another type of filter controls which mailbox items are retrieved based on the folder that contains the item. Having an initial synchronization that is filtered has several advantages. For instance, the synchronizing the entire mailbox for each user on the collaboration suite server 210 and the caches 340 a . . . 340 n puts a significant load on network bandwidth and on the collaboration suite server 210 ; a filtered initial synchronization avoids such loads. Furthermore, synchronizing each user's entire mailbox with the cache 340 makes for a very large size of each cache 340 a . . . 340 n , which can cumulatively impact the collaboration suite synchronization client 220 . Another benefit of the filtered initial synchronization is that it reduces the amount of time required to populate the local cache 340 .
Once the initial synchronization is performed, the required data from each user's mailbox is on the cache 340 . These data from caches 340 a . . . 340 n are synchronized (not shown in FIG. 4 ) with the user's devices 240 a . . . 240 n (collectively 240 ) by the synchronizer 350 . The synchronization with the user devices 240 may happen concurrently with the initial filtered synchronization. That is, in one embodiment, as the user's mailbox is being replicated to the local caches 340 , the user device synchronization server 230 is also synchronizing the data to the user devices 240 .
In one embodiment, the initial filtered synchronization (step 410 ) is non-blocking. That is, the local cache 340 receives any new mailbox items the user receives while the initial filtered synchronization (step 410 ) is ongoing. The importance of this can be easily understood by considering the following scenario. Let us assume that a user has a few thousand mailbox items that will be handled during the filtered initial synchronization (step 410 ). This may take a few minutes to execute. During this time, new messages may be received in the user's mailbox. Although the synchronizer 350 is busy completing the filtered initial synchronization (step 410 ), a secondary synchronizer 352 ensures that these new messages are received by the cache 340 in real-time. This secondary synchronizer 352 gets notified by the server in real-time (via the real-time notifier 360 ) when new items arrive in the user's mailbox and it adds these mailbox items to the caches 340 in real-time. This is especially important for some cases (e.g., the BES) because over-the-air provisioning is done via email. So, as an example, when the user's administrator provisions a BES account for the user, the user does not need to wait for the cache 340 on the BES to be fully synchronized before he can provision his device 240 . Rather, he can provision it right away.
As explained above, in one embodiment, this secondary synchronization process (not shown in FIG. 4 ) is also running while the initial filtered synchronization (step 410 ) is proceeding. This secondary synchronization makes sure that the local cache 340 receives any new mailbox items for the user received on the collaboration suite server 210 . This occurs in real time.
Once 410 has completed, based on real-time local and server notifications (via the real-time notifier 360 ), progressive synchronization (not shown) occurs between the caches 340 and the collaboration suite server 210 , so that any changes are reflected in the caches 340 and the collaboration suite server 210 with as little delay as possible.
Since the user device synchronization server 230 conducts all its operations against the local caches 340 , the load on the collaboration suite server 210 is vastly reduced. The collaboration suite server 210 only needs to synchronize with the caches 340 , which creates much less load on it than passing through all the user device synchronization server 230 operations (e.g., searching, sorting, etc. of mailbox items) directly to the collaboration suite server 210 .
As new data is added to the data store 215 on the collaboration suite server 210 for each user, these data are progressively synchronized in real time (step 420 ) with the corresponding cache 340 a . . . 340 n . In one embodiment, the collaboration suite server 210 notifies the collaboration suite synchronization client 220 when a new mailbox item is received by it. Similarly, the collaboration suite synchronization client 220 notifies the collaboration suite server 210 when a new mailbox item is received by it. The caches 340 are continually synchronized (step 415 ) with user devices 240 by the user device synchronization server 230 .
In one embodiment, the data stored in each cache 340 a . . . 340 n includes a mailbox revision number. A token including this revision number of the mailbox version in the caches 340 a . . . 340 n is passed to the collaboration suite server 210 by the synchronizer 250 . The collaboration suite server 210 then checks the revision number of each mailbox against the revision number in the data store 215 corresponding to the mailbox. If the revision number in the token sent over by the synchronizer 250 is the same as the revision number in the data store 215 for that mailbox, then that mailbox does need to be synchronized at that time. If the revision number in the token is different, then something has changed since the last synchronization, and the mailbox needs to be synchronized. This prevents needless synchronization of mailboxes when nothing has changes, while at the same time ensuring timely synchronization when any change occurs.
As time goes on, the size of both the caches 340 a . . . 340 n , and the data on the user's devices 240 a . . . 240 n grows. Eventually, very large sizes of these caches 340 a . . . 340 n will cumulatively impact the collaboration suite synchronization client 220 , and large sizes of data on the user's devices 240 a . . . 240 n will impact the user devices 240 a . . . 240 n . In order to control these sizes, in accordance with an embodiment of the present invention, reaping (step 440 ) is performed on these caches 340 .
Reaping is the selective removal of data across various folders in a user's mailbox from the cache 340 . In one embodiment, some mailbox items are reaped by the reaper 370 based on a date (e.g., date received prior to 7 days ago is deleted from cache 340 ) while other mailbox items (e.g., contacts) are not reaped. Still other mailbox items are reaped with more complicated criteria—for instance, calendar entries are reaped if they are older than a few days, but recurring calendar entries are not reaped.
In one embodiment, this reaping of a user's mailbox is transparent to the user of the user device 240 . That is, reaped items remain on the collaboration suite server 210 , and the user 240 is not aware that data has been reaped. The user can request a mailbox item which has been removed from the local cache 340 by the reaper 370 , and in such a situation, the on-demand fetcher 380 will fetch the requested mailbox item from the data store 215 on the collaboration suite server 210 . This is discussed in further detail below.
In one embodiment, the reaping occurs at regular intervals. As mentioned above, in one embodiment, at any given time, only data from the last several (e.g., seven days) may be kept in the cache 340 . In another embodiment, the reaping may be based on the size of the cache. For instance, at any given time, the size of each cache may not exceed a predetermined size, and reaping occurs to keep the size of each cache under this predetermined size. The parameters for reaping (e.g., the periodicity of reaping) are specified by the system administrator in accordance with an embodiment of the present invention. In another embodiment, the user can specify the parameters for reaping. In one embodiment, when an item is reaped, its metadata is still viewable in the cache 340 , but large properties are not. For instance, if a mailbox item includes attachments, large text message bodies, large html message bodies, etc., these are removed. So the mailbox item will be in the cache 340 , but when the large fields are requested, the mailbox item will need to be refreshed from the collaboration suite server 210 . (See discussion regarding obtaining mailbox items on-demand (step 470 ) below.) It is to be noted that, over a long period of time, the data on the device 240 will be, in one embodiment, a superset of the data in the cache 340 , since many mailbox items may have been reaped from the cache 340 , but are held on the device 240 depending on for how long the device 240 has been configured to hold mailbox items.
Referring back to FIG. 4 , when a mailbox item is needed (e.g., the user requests a mailbox item on the user's device 240 ), a system in accordance with an embodiment of the present invention checks (step 450 ) if the needed mailbox item is on the cache 340 . If the mailbox item is on the cache 340 , it is provided (step 460 ) to the user's device 240 .
It may be that the mailbox item requested by the user is not available on the cache 340 . This may happen, for instance, when the user requests a much older email that is not available on the cache, either due to the filtered initial synchronization and/or due to the reaping. When this happens, the mailbox item requested is obtained on-demand (step 470 ) by the on-demand fetcher 380 from the collaboration suite server 210 on an as-needed basis. This happens transparently to the user device synchronization server 230 . The user can thus have seamless access to a superset of the data in the cache 340 .
As mentioned above, when a mailbox item is opened, or acted upon in any way, and the mailbox item is not in the cache 340 , the mailbox item is fetched from the collaboration suite server 210 and refreshed in the cache 340 . Any other operations that need to be conducted on this mailbox item are deferred until the current operation has completed. Operations can include simply providing the item to the user device 240 , modifications of a property of the item (contact first name, appointment start time, add/remove attachment on an item, etc.), modification of the location of the item (moving it to a new folder), deletion of the item, and so on.
While particular embodiments and applications of the present invention have been illustrated and described, it is to be understood that the invention is not limited to the precise construction and components disclosed herein. The present invention is in no way limited to the BES server, or to the ZIMBRA COLLABORATION SUITE® (from the assignees of this application). For example, embodiments of the present invention may be used for any form of replication from the collaboration suite application to a third party store. For instance, a fan-out style of replication may be useful where many replicas of mailboxes are needed. Various other modifications, changes, and variations which will be apparent to those skilled in the art may be made in the arrangement, operation and details of the method and apparatus of the present invention disclosed herein, without departing from the spirit and scope of the invention as defined in the following claims. It should further be recognized by those of ordinary skill in the art that one or more embodiments of the present invention may be implemented as one or more computer programs or as one or more computer program modules embodied in one or more computer readable media.
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A system and method for creating a cached mode is created for some applications, such as for use with BES. Operations on the mailbox items are conducted off the cache, rather than off the collaboration suite server itself, thus reducing the load on the collaboration suite server. According to one aspect of the present invention, a filtered initial synchronization is performed with the cache in the client device to further reduce the load on the collaboration suite server as well as the required bandwidth. In one embodiment of the present invention, mailbox items on the local cache are periodically reaped so as to not over-burden the disk space in the client device. In one embodiment of the present invention, mailbox items not present in the cache can be requested on-demand from the collaboration suite server.
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CROSS REFERENCE TO CO-PENDING APPLICATIONS
U.S. patent application Ser. No. 09/447,611, filed Nov. 23, 1999, and entitled, “LOW INPUT VOLTAGE, LOW COST, MICRO-POWER DC-DC CONVERTER”; U.S. patent application Ser. No. 09/447,999, filed Nov. 23, 1999, and entitled, “STEPPER MOTOR DRIVING A LINEAR ACTUATOR OPERATING A PRESSURE CONTROL REGULATOR”; U.S. patent application Ser. No. 09/448,102, filed Nov. 23, 1999, and entitled, “LOW INPUT VOLTAGE, HIGH EFFICIENCY, DUAL OUTPUT DC TO DC CONVERTER”; and U.S. patent application Ser. No. 09/448,000, filed Nov. 23, 1999, and entitled, “ELECTRONIC DETECTING OF FLAME LOSS BY SENSING POWER OUTPUT FROM THERMOPILE” are commonly assigned co-pending applications incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to systems for control of a gas appliance incorporating a flame and more particularly relates to fuel control valve systems.
2. Description of the Prior Art
It is known in the art to employ various appliances for household and industrial applications which utilize a fuel such as natural gas (i.e., methane), propane, or similar gaseous hydrocarbons. Typically, such appliances have the primary heat supplied by a main burner with a substantial pressurized gas input regulated via a main valve. Ordinarily, the main burner consumes so much fuel and generates so much heat that the main burner is ignited only as necessary. At other times (e.g., the appliance is not used, etc.), the main valve is closed extinguishing the main burner flame.
A customary approach to reigniting the main burner whenever needed is through the use of a pilot light. The pilot light is a second, much smaller burner, having a small pressurized gas input regulated via a pilot valve. In most installations, the pilot light is intended to burn perpetually. Thus, turning the main valve on provides fuel to the main burner which is quickly ignited by the pilot light flame. Turning the main valve off, extinguishes the main burner, which can readily be reignited by the presence of the pilot light.
These fuels, being toxic and highly flammable, are particularly dangerous in a gaseous state if released into the ambient. Therefore, it is customary to provide certain safety features for ensuring that the pilot valve and main valve are never open when a flame is not present preventing release of the fuel into the atmosphere. A standard approach uses a thermogenerative electrical device (e.g., thermocouple, thermopile, etc.) in close proximity to the properly operating flame. Whenever the corresponding flame is present, the thermocouple generates a current. A solenoid operated portion of the pilot valve and the main valve require the presence of a current from the thermocouple to maintain the corresponding valve in the open position. Therefore, if no flame is present and the thermocouple(s) is cold and not generating current, neither the pilot valve nor the main valve will release any fuel.
In practice, the pilot light is ignited infrequently such as at installation, loss of fuel supply, etc. Ignition is accomplished by manually overriding the safety feature and holding the pilot valve open while the pilot light is lit using a match or piezo igniter. The manual override is held until the heat from the pilot flame is sufficient to cause the thermocouple to generate enough current to hold the safety solenoid. The pilot valve remains open as long as the thermocouple continues to generate sufficient current to actuate the pilot valve solenoid.
The safety thermocouple(s) can be replaced with a thermopile(s) for generation of additional electrical current. This additional current may be desired for operating various indicators or for powering interfaces to equipment external to the appliance. Normally, this requires conversion of the electrical energy produced by the thermopile to a voltage useful to these additional loads. Though not suitable for this application, U.S. Pat. No. 5,822,200, issued to Stasz; U.S. Pat. No. 5,804,950, issued to Hwang et al.; U.S. Pat. No. 5,381,298, issued to Shaw et al.; U.S. Pat. No. 4,014,165, issued to Barton; and U.S. Pat. No. 3,992,585, issued to Turner et al. all discuss some form of voltage conversion.
Upon loss of flame (e.g., from loss of fuel pressure), the thermocouple(s) ceases generating electrical current and the pilot valve and main valve are closed, of course, in keeping with normal safety requirements. Yet this function involves only a binary result (i.e., valve completely on or valve completely off). Though it is common within vehicles, such as automobiles, to provide variable fuel valve control as discussed in U.S. Pat. No. 5,546,908, issued to Stokes, and U.S. Pat. No. 5,311,849, issued to Lambert et al., it is normal to provide static gas appliances with a simple on or off, linearly actuated valve having the desired safety features.
Yet, there are occasions when it is desirable to adjust the valve outlet pressure regulation point of the main burner supply valve of a standard gas appliance. These include changes in mode (i.e., changes in the desired intensity of the flame) and changes in the fuel type (e.g., a change from propane to methane). U.S. Pat. No. 5,234,196, issued to Harris; U.S. Pat. No. 4,816,987, issued to Brooks et al.; U.S. Pat. No. 5,873,351, issued to Vars et al.; and U.S. Pat. No. 5,150,685, issued to Porter et al., suggest approaches to variable valve positioning of a gas appliance. However, the introduction of an entirely new valve design is likely to introduce severe regulatory difficulties. The present safety valve approach has been used for such a long time with satisfactory results. Proof of safe operation of a new approach to valve design would require substantial costly end user testing.
SUMMARY OF THE INVENTION
The present invention overcomes the disadvantages of the prior art by providing a main burner valve for a gas appliance which offers the user the opportunity to quickly and easily change the main valve outlet pressure regulation point to accommodate changes in fuel type. The main burner valve of the present invention utilizes a standard, linearly actuated valve design having proven safety features, but which also offers precisely controllable differing outlet pressure. Linear actuation is important, because it offers the normal safety features associated with the industry standard of full off upon flame out. However, because the valve of the present invention may be positioned along the entire length of its travel from full open to full closed, the valve is totally adjustable permitting changes in mode, fuel input, and other outlet pressure related features.
In accordance with the preferred mode of the present invention, a thermopile is thermally coupled to the pilot flame. As current is generated by the thermopile, it is converted via a DC-to-DC converter to a regulated output and an unregulated output. The regulated output powers a microprocessor and other electronic circuitry which control operation of the main fuel valve in response to sensed conditions, operator inputs, and certain stored data. The unregulated output powers various mechanical components including a stepper motor.
The stepper motor is mechanically coupled to a linear actuator which precisely positions the main fuel valve. Because the main fuel valve is linearly actuated, it operates in known fashion with respect to the industry proven flame out safety features. Yet, the stepper motor, under direct control of the microprocessor, positions the linear actuator for precise valve positioning and therefore, fuel input modulation to the burner.
The use of a stepper motor means that any selected valve position is held statically by the internal rachet action of the stepper motor without quiescent consumption of any electrical energy. That makes the electrical duty cycle of the stepper motor/valve positioning system extremely low. This is a very important feature which permits the system to operate under the power of the thermopile without any necessary external electrical power source. In fact, the stepper motor duty cycle is sufficiently low, that the power supply can charge a capacitor slowly over time such that when needed, that capacitor can power the stepper motor to change the position of the linear actuator and hence the main fuel valve outlet pressure regulation point.
In accordance with the present invention, the gas appliance is calibrated during the manufacturing process. The stepper motor values and hence the valve positioning data corresponding to the desired valve settings are determined empirically for the various fuel types. This information is stored within non-volatile memory of the microprocessor. Thus, a table of stepper motor commands are available to the microprocessor for rapid changes of fuel type.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects of the present invention and many of the attendant advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which like reference numerals designate like parts throughout the figures thereof and wherein:
FIG. 1 is a simplified electrical schematic diagram of the present invention;
FIG. 2 is a simplified block diagram of the microprocessor of the present invention;
FIG. 3 is a detailed electrical block diagram;
FIG. 4 is a plan view of the valve assembly; and
FIG. 5 is a flow diagram showing calibration of the valve assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a very basic electrical diagram 22 of the power circuitry of the present invention. Thermopile 24 is structured in accordance with the prior art. Resistor 26 represents the internal resistance of thermopile 24 .
Pilot valve 28 has a solenoid (not separately shown) which holds the pilot valve closed whenever sufficient current flows through the circuit. Similarly, the internal solenoid (also not separately shown) main valve 32 holds the main valve closed whenever sufficient current flows through the associated circuit.
DC-to-DC conversion facility 36 converts the relatively low voltage output of thermopile 24 to a sufficiently large voltage to power the electronic circuitry, including the microprocessor. In accordance with the preferred mode of the present invention, DC-to-DC conversion facility 36 consists of two DC-to-DC converters. The first converter operates at the extremely low thermopile output voltages experienced during combustion chamber warm up to generate a higher voltage to start the higer efficiency, second DC-to-DC converter. The other DC-to-DC converter, once started, can keep converting at much lower input voltage and generate much more power from the limited thermopile output for the system during normal operation. A more detailed description of the second device is available in the above identified and incorporated, commonly assigned, co-pending U.S. Patent Applications.
FIG. 2 is a simplified diagram showing the basic inputs and outputs of microprocessor 60 . In the preferred mode, microprocessor 60 is an 8-bit AVR model AT90LS8535 microprocessor available from ATMEL. It is a high performance, low power, restricted instruction set (i.e., RISC) microprocessor. In the preferred mode, microprocessor 60 is clocked at one megahertz to save power, even though the selected device may be clocked at up to four megahertz.
The two primary inputs to microprocessor 60 are the thermopile output voltage received via input 62 and the manual mode change information received via input 64 . The thermopile output voltage is input once per second. The mode change information, on the other hand, is received a periodically in response to manual action by the user.
Output 66 controls operation of the stepper motor. As is explained in more detail below, this affects management of the main fuel valve orifice size. Output 68 is the on/off control for the external circulation fan. Output 70 controls the radio frequency receiver through which an operator can communicate via a remote control device.
FIG. 3 is a detailed block diagram of the inputs and outputs of microprocessor 60 . One megahertz crystal 84 clocks microprocessor 60 . The output of crystal 84 is also divided down to provide an interrupt to microprocessor 60 once per second. This interval is utilized for sampling of the thermopile output voltage Indicator 112 permits early notification of flame on to the user.
Manual mode switch 86 permits an operator to select local mode or remote mode. Similarly, manual switch 88 is used to select the input fuel type, so that the main valve outlet pressure regulation point can be switched between propane and methane. Each of these alternative switch positions cause microprocessor 60 to consult a particular corresponding entry within the valve positioning table stored in the non-volatile memory of microprocessor 60 . These entries provide the necessary information for microprocessor 60 to direct the stepper motor to set the main burner valve outlet pressure to the proper value. The method for determining the valve positioning table entries is described in detail below.
DC-to-DC converter 36 can receiver inputs from up to two thermopiles. Inputs 94 and 96 provide the positive and negative inputs from the first thermopile, whereas inputs 90 and 92 provide the positive and negative inputs from the second thermopile, respectively. Output 102 is the unregulated output of DC-to-DC converter 36 . This output has a voltage varying between about 6 volts and 10 volts. The unregulated output powers the mechanical components, including the stepper motor. Line 104 is a 3 volt regulated output. It powers microprocessor 60 and the most critical electronic components. Line 106 permits microprocessor to power DC-to-DC converter 36 up and down. This is consistent with the voltage sampling and analysis by microprocessor 60 which predicts flame out conditions.
Line 72 enables and disables pilot valve driver 72 coupled to the pilot valve via line 98 . Similarly, line 110 controls main valve driver 74 coupled to the main valve via line 100 . This is important because microprocessor 60 can predict flame out conditions and shut down the pilot and main valves long before the output of the thermopile is insufficient to hold the valves open. A more detailed description of this significant feature may be found in the above referenced, co-pending, commonly assigned, and incorporated U.S. Patent Applications.
Stepper motor drivers 76 are semiconductor switches which permit the output of discrete signals from microprocessor 60 to control the relatively heavy current required to drive the stepper motor. In that way, line 66 controls the stepper motor positioning in accordance with the direction of the microprocessor firmware. Line 114 permits sensing of the stepper motor status. Lines 122 , 124 , 126 , and 130 provide the actual stepper motor current.
In the preferred mode of practicing the present invention, the gas appliance is a fireplace. The thermopile output is not sufficient to power the desired fan. However, the system can control operation of the fan. Therefore, line 132 provides the external power which is controlled 15 by fan driver 80 . Lines 128 and 129 couple to optical isolation device 78 for coupling via lines 68 , 116 , and 118 to microprocessor 60 . Line 134 actually powers the fan.
The fireplace of the preferred mode also has radio frequency remote control. A battery operated transmitter communicates with rf receiver 82 via antenna 136 . Lines 70 and 120 provide the interface to microprocessor 60 . Rf receiver 82 is powered by the 3 volt regulated output of DC-to-DC converter 36 found on line 104 .
FIG. 4 is a plan view of the valve assembly 140 of the preferred mode of the present invention. Fuel inlet 150 has standard fittings. Similarly, gas outlet 148 includes a standard coupling. Regulator cap 142 fits within housing cap 144 as shown (a better view is found in the section of FIG. 5 ). Motor housing 146 contains the linear actuator and stepper motor (neither shown in this view).
FIG. 5 is a flow diagram showing the manner in which the entries are empirically determined for the valve positioning table. Entry is via element 160 . The propane valve positioning values are determined first. The stepper motor opens the valve to its maximum position at element 164 .
At element 166 , the stepper motor decrements the outlet pressure of the valve. The outlet pressure is determined at element 168 . If the pressure is not as desired, control is returned to element 166 for a further decrement of the outlet pressure. When the valve pressure has been decremented to the desired point, control is given by element 168 to element 170 . The stepper motor positioning command is stored in the valve positioning table by element 170 . Element 72 determines whether there are other propane entries to be determined. If yes, control is given to element 166 to continue the process.
After element 172 finds that all of the propane entries have been made in the valve positioning table, control is given to element 174 to initialize for determine the methane (or natural gas) values. The process is essentially repeated for methane. Element 176 opens the valve to the maximum outlet pressure. Decrementation of the valve outlet pressure is accomplished by element 178 . Element 180 determines if the desired value has been reached. If no, the process continues at element 178 . If yes, element 182 records the stepper motor value. Element 184 ascertains whether all of the methane values have been determined. If not, control is given to element 178 . If yes, element 186 completes the valve positioning table, and exit is made via element 188 .
Having thus described the preferred embodiments of the present invention, those of skill in the art will be readily able to adapt the teachings found herein to yet other embodiments within the scope of the claims hereto attached.
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An apparatus for and method for providing easy and rapid conversion from a first fuel to a second fuel in a gas appliance. The gas appliance has a variable fuel valve controlled by a microprocessor. A table stored in non-volatile memory has an entry for each of the fuels to be burned in the gas appliance. The table entries are empirically determined at the time of manufacture.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an apparatus for manufacturing a semiconductor device, and more particularly, to a dry etching apparatus.
2. Description of the Related Art
A dry etching apparatus uses plasma to carry out various processes in the manufacturing of a semiconductor device. In a dry etching process, a reaction gas is injected into the dry etching apparatus and external power having the frequency of a radio wave is applied to a silicon cathode and an anode of the dry etching apparatus. The energy of electrons accelerated by an RF electric field formed between the cathode and the anode is increased as the electrons elastically collide repeatedly against molecules of the reaction gas. Then, the highly energized electrons collide non-elastically with the molecules of the reaction gas whereby the molecules of the reaction gas are ionized and excited to generate plasma. Negatively charged plasma gases flow to the anode due to a difference in potential between the cathode and the anode. There, the plasma reacts with a wafer located on the anode to generate a material having a high vapor pressure and a volatile material, to thereby etch the wafer.
If the dry etching process described above is to be performed accurately and effectively, the plasma stream must be confined to the wafer supported on the anode and impurities must be suppressed.
However, an examination of a conventional dry etching apparatus (FIG. 1) reveals that sunflower-shaped particles of a polymer and particle contaminants 30 are deposited on an aluminum ring 14 extending along the periphery of an electrostatic chuck (ESC) 12 provided in the lower portion 10 of a processing chamber of the apparatus, and on a plasma confinement ring 24 supporting a silicon cathode 22 in an upper portion 20 of the processing chamber. The aluminum ring 14 is provided to enhance the uniformity of the plasma density, whereas the confinement ring 24 is provided to confine the plasma stream to the area of the wafer.
The present inventor has determined that the deposition of the polymer and of the particle contaminants 30 are caused by occurrences of micro-arcing between screws 26, which fix the confinement ring 24 in place, and the aluminum ring 14 extending along the periphery of the electrostatic chuck 12. The micro-arcing acts at openings for air stream control which are formed in the silicon cathode 22 and an aluminum baffle, mounted on the silicon cathode 22, to control the flow of gas. The particles of silicon or aluminum which are produced as a result of the micro-arcing contaminate the wafer during the dry etching process. Also, the plasma confinement ring 24 does not completely confine the plasma stream to just the area of the wafer. Rather, the plasma diffuses onto the aluminum ring 14. There, some of the plasma combines with the particle contaminants. The plasma and the plasma combined with the particle contaminants are burned by the micro-arcing to form the sunflower-shaped polymer and particles 30 shown in FIG. 1.
The contamination of the wafer, and the presence of the polymer and particle contaminants 30 adversely affects the dry etching process to the point where the yield of satisfactorily etched products is below expectations.
SUMMARY OF THE INVENTION
It is therefore one object of the present invention to provide a dry etching apparatus in which micro-arcing is suppressed.
It is another object of the present invention to provide a dry etching apparatus which prevents a wafer being etched from becoming contaminated.
To achieve these objects, the present invention provides a dry etching apparatus including a plasma confinement ring secured by screws to a cathode, an anode, and a metal focusing ring extending around the anode for enhancing the uniformity of the plasma. The screws are located a maximum distance away from the focusing ring and the electric RF field. The screws are preferably covered with caps of electrically insulative material. Furthermore, the metal of the focusing ring is preferably anodized. The screws can be of an anodized metal or of an insulating material.
All of these measures help the present invention achieve the above-mentioned object of preventing the occurrence of micro-arcing during the etching process and hence, prevent contaminants from being produced.
The confinement ring functions as a physical barrier that confines the plasma stream to within the projected area of the wafer. To this end, the height of the confinement ring (distance by which the confinement ring protrudes downwardly from the cathode) is selected to be 7˜9 mm. The confinement ring is preferably formed of ceramic or at least of a material such as anodized aluminum and quartz which will not be damaged by the plasma. Furthermore, the confinement ring can have a TEFLON (polytetrafluoroethylene) coating to reduce the friction between the cathode and the confinement ring. All of these measures help the present invention achieve the above-mentioned second object of the present invention of preventing the contamination of the wafer.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects and advantages of the present invention will become more apparent from the following detailed description of a preferred embodiment thereof made with reference to the attached drawings, of which:
FIG. 1 is a perspective view of a conventional dry etching apparatus showing polymer and contamination particles formed therein;
FIG. 2 is a sectional view of one embodiment of the dry etching apparatus according to the present invention;
FIG. 3 is an enlarged view of a section of the dry etching apparatus encircled by `A` in FIG. 2;
FIG. 4 is a graph showing the relationship between the time during which RF power is supplied and the generation of particle contaminants, when the dry etching apparatus of FIG. 2 is used; and
FIG. 5 is a graph showing the relationship between the time during which RF power is supplied and the generation of particle contaminants, when the conventional dry etching apparatus of FIG. 1 is used.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will now be described more fully hereinafter with reference to the accompanying drawings. In the drawings, the size and relative position of the elements of the dry etching apparatus are exaggerated for clarity. Furthermore, like numbers refer to like elements throughout the drawings.
Referring first to FIG. 2, an electrostatic chuck (ESC) 112 capable of holding a wafer 118 serves as an anode. The ESC 112 is disposed in the bottom portion of a processing chamber 100 of the dry etching apparatus. Rings 114A, 114B and 116 extend around a peripheral portion of the ESC 112. The ring 114B is made of metal and is a focusing ring primarily responsible for ensuring that the plasma density is uniform. This focusing ring 114B may be made of pure aluminum, but is preferably made of anodized aluminum or stainless steel, to suppress micro-arcing. The ring 114A extends over the top of the metal focusing ring 114B and serves as an insulating ring to prevent the ring 114B from being directly exposed to the plasma and to prevent arcing. The ring 116 extends over the periphery of the metal focusing ring 114B and the insulating focusing ring 114A and also serves as an insulating ring. The wafer 118 which is to be dry etched is loaded on the ESC 112, and the rings 114A and 116 help to maintain the wafer 118 in place.
A cathode 122 and a baffle 128 stacked thereon are disposed in the top portion of the processing chamber 100 of the dry etching apparatus. A confinement ring 124 supports the cathode 122 in position in the upper portion of the processing chamber 100 of the dry etching apparatus. The confinement ring 124 protrudes downward from the cathode 122 by a predetermined height `H` to confine the plasma to an area corresponding to the projected area of the wafer 116. The confinement ring 124 is formed of ceramic or any other material which is not damaged by plasma, e.g., anodized aluminum or quartz. The confinement ring 124 is also preferably coated with an insulating material such as TEFLON (a smooth, heat resistant/scratch resistant polymer coating) to reduce the friction between the silicon cathode 122 and the confinement ring 124 and thus, to prevent silicon particles from being generated by the rubbing of the silicon cathode 122 and the confinement ring 124.
The confinement ring 124 is fixed to an upper sealing plate 130 by screws 126. The screws 126 are located a maximum distance D1 away from the focusing ring 114B, and are spaced from the radio frequency (RF) electric field region, i.e., from the region in which the plasma is formed. The screws 126 are made of an anodized metal to prevent micro-arcing or of an insulating material such as TEFLON. When the screws 126 are made of metal, a respective insulating cap 126A preferably covers each of the screws 126 to prevent a certain amount of micro-arcing from occurring. Each insulating cap 126A preferably has a vacuum hole 127 extending horizontally therethrough, i.e., parallel to the focusing ring 114B, to vent the internal space between the screw 126 and the confinement ring 124 or upper sealing plate 130 after the dry etching process is completed.
The dry etching apparatus also includes a gas inlet 140 through which a reaction gas is introduced into the processing chamber at the top portion thereof, and a gas outlet 170 through which the reacted gas is exhausted from the processing chamber 100 at the bottom portion thereof. Also, an RF power supply 150 is connected to the cathode 122 and the anode 112.
When the reaction gas is injected into the gas inlet 140 and the power is applied to the cathode 122 and the anode 112 by the RF power supply 150, an RF electrical field is formed between the cathode 122 and the anode 112 and the reaction gas is converted to plasma 160 by the RF electrical field. The plasma 160 impinges the wafer 118 supported on the anode 112, thereby dry etching the wafer 118.
The confinement ring 124, and the location of the screws 126 relative to the rings 114A, 114B and 116, will now be described in more detail with reference to FIG. 3.
The degree to which the plasma is confined to the area of the wafer 118 is a function of the amount by which the confinement ring 124 protrudes downward from the cathode 122 (physical barrier height `H`). Thus, the confinement ring 124 of the present invention has a physical barrier height `H` which ensures that the plasma impinges only the wafer 118. For instance, when all other elements of the dry etching apparatus have the same sizes as those of the conventional dry etching apparatus, the physical barrier height of the confinement ring of the present invention is 7˜9 mm, which is 2˜4 mm higher than the physical barrier height (5 mm) of the conventional confinement ring.
The screws 126 which fix the confinement ring 124 to the upper sealing plate 130 are disposed outside the region in which the RF electrical field is formed but at locations at which the screws 126 still, of course, have the ability to keep the confinement ring 124 assuredly fixed to the upper sealing plate 130. More specifically, each screw 126 is located the maximum distance D3 away from a respective location P on the inner peripheral edge of the confinement ring 124, as taken along a line extending in the radial direction of the confinement ring 124 through P and the screw. This location P is directly opposite an end portion of the ESC 112 where the edge of the wafer 118 lies. Each screw 126 is thus also located a maximum distance D1 away from the focusing ring 114B. When the sizes of elements of the dry etching apparatus according to the present invention are the same as those of the conventional dry etching apparatus, the screws 126 are each located 2˜5 mm further outside of the RF electrical field than the screws of the conventional dry etching apparatus. For instance, when a distance D2 between the screw 126' and the location P of the confinement ring 124 in the conventional dry etching apparatus is 7 mm, the distance D3 between the screw 126 and the position P of the confinement ring 124 of the present invention is 9˜12 mm. Even if the screws 126 of the present invention are slightly affected by the electric field, micro-arcing is suppressed because the distance D1 between each screw 126 and the metal ring 114B is maximized.
A comparison between the present invention and the conventional dry etching apparatus will now be described.
First, the number of particle contaminants generated during a dry etching process performed by a dry etching apparatus according to the present invention was measured.
A wafer 118 having a 1500 Å thick oxide layer was chucked by the ESC 112 of the dry etching apparatus shown in FIG. 2, and then CF 4 , CHF 3 and Ar were injected into the processing chamber through gas inlet 140. Then, plasma was generated by applying the RF power to the cathode 122 and the anode 112 with the RF power supply 150 to etch the oxide layer. While the RF power was being applied, the number of particles generated in the dry etching apparatus was measured at predetermined time intervals during a period of time from 0 minutes to 3750 minutes. The results are shown in the graph of FIG. 4.
Next, the conventional dry etching apparatus shown in FIG. 1 was operated under the same conditions, and the number of particles generated in the conventional dry etching apparatus was also measured at predetermined time intervals. The results of these measurements are shown in the graph of FIG. 5.
As shown in FIG. 4, the number of particle contaminants generated in the dry etching apparatus of the present invention is almost always less than 10. On the other hand, as is clear from FIG. 5, the number of particle contaminants generated in the conventional dry etching apparatus is oftentimes greater than 10 and at times ranges to more than 50.
According to the dry etching apparatus of the present invention, the screws 126 for fixing the confinement ring 124 to the upper sealing plate 130 are located at positions which ensure a sufficient securing of the confinement ring 124 to the sealing plate 130, which are outside of an RF electric field, and which are a maximum distance D1 away from the metal focusing ring 114B. Thus, micro-arcing will not occur between the screws 126 and the focusing ring 114B during the dry etching process. Also, the screws 126 are provided with insulating caps, an insulating ring(s) is/are provided over the metal focusing ring 114B, and the screws 126 and the focus ring 114B are made of an anodized metal to effectively suppress the micro-arcing. Also, the physical barrier height of the confinement ring 124 is precisely set to ensure that the plasma impinges only the wafer 118, and not the focusing ring. Thus, when using the dry etching apparatus of the present invention, micro-arcing does not occur and the plasma is only distributed onto the wafer, whereby the generation of particle contaminants is suppressed and the yield of the products produced by the dry etching process is kept high.
Although the present invention has been described above with respect to the preferred embodiment thereof, various changes thereto and variations thereof will become apparent to those of ordinary skill in the art. Accordingly, all such changes and modifications are seen to be within the true spirit and scope of the present invention as defined by the appended claims.
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A dry etching apparatus used for manufacture of a semiconductor device includes a plasma confinement ring secured by screws to a cathode, an anode, and a metal focusing ring extending around the anode for enhancing the uniformity of the plasma. The screws are located a maximum distance away from the focusing ring. Thus, micro-arcing is prevented from occurring between the focusing ring and the screws. The confinement ring is also designed to distribute the plasma stream only onto the wafer, so that the generation of contamination particles is suppressed during etching.
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CROSS REFERENCE TO RELATED APPLICATION
[0001] The present application is a continuation of international application PCT/EP 2004/014403, filed 17 Dec. 2004, and which designates the U.S. The disclosure of the referenced application is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The invention relates to a melt-blown method for melt spinning fine non-woven fibers, as well as to a device for carrying out said method.
[0003] In the production of non-woven microfibers a plurality of fiber strands are extruded from a polymer melt through nozzle holes of a spinneret and then drawn with a blowing stream into microfibers. Such fibers exhibit an average fiber diameter of usually <10 μm. In the state of the art such methods are called melt-blown methods. The blowing stream is preferably produced from hot air that is blown with a high expenditure of energy on the fiber strands. The blowing stream leads to drawing and bursting of the fiber strands so that fine non-woven fibers of finite length are produced.
[0004] DE 33 41 590 A1 and corresponding U.S. Pat. No. 4,526,733 disclose such a method, where a fluid, which is not heated up, is used as the blowing stream. In principle, such relatively cold blowing streams exhibit the advantage that there is no need to heat up the fluid. This method could also produce fine fibers made of thermoplastic polymers, which exhibit a fineness of less than 10 μm.
[0005] Irrespective of whether the prior art melt-blown method is carried out with a hot blowing medium or with a cold blowing medium, as disclosed in the DE 33 41 590 A1, the fiber strands are usually torn into finite fibers. In addition to the disadvantageous formation of fuzz, such fibers lead, upon being deposited to form a non-woven fabric, to irregularities in the physical properties due to the conglutinated fiber pieces. In particular, such non-woven fabrics can tolerate only slight tensile strengths owing to the finite fiber pieces.
[0006] DE 199 29 709 A1 discloses another method for producing fine non-woven fibers. In this method the fiber strands are split into fine fibers by means of a gas stream. The prior art method, which is referred to as the Nanoval method in professional circles, is based on generating a pressure effect on the fiber strand subject to the action of a gas stream and a nozzle unit. Said pressure effect causes the fiber strand to burst so that a plurality of fine, essentially endless fibers is produced. At the same time the hydrostatic pressure, prevailing in the interior of the fibers, is greater than the gas pressure that envelops the fiber strands and by means of which the bursting of the fiber strands is achieved. Then the fibers are guided—subject to the action of the gas stream—to a depositing area and are deposited as a non-woven fabric.
[0007] All of the state of the art melt-blown methods run the risk that the individual fibers will conglutinate before the final solidification and lead to undesired points of discontinuity in the non-woven fabric.
[0008] Therefore, an object of the invention is to provide a melt-blown method for melt spinning fine non-woven fibers of the type described in the introductory part. According to this method, a high quality microfiber could be produced at a relatively low expenditure of energy.
[0009] Another goal of the invention is to provide non-woven fibers for producing a non-woven fabric, which exhibits improved physical properties.
[0010] In addition, an object of the invention is to improve a melt-blown method and a melt-blown device for melt spinning fine non-woven fibers in such a manner that a microfiber is produced that exhibits maximum uniformity and continuity in order to attain, during their subsequent manufacture into a non-woven fabric, a uniform distribution of the fibers during the depositing process.
SUMMARY OF THE INVENTION
[0011] The above objectives and others are realized according to the invention by providing, in one embodiment, a method for melt spinning fine non-woven fibers, comprising extruding a polymer melt through several nozzle holes of a spinneret in order to form several fiber strands, and immediately after emerging from the nozzle holes, acting on the fiber strands with a cold blowing stream that, subject to the action of an overpressure, flows through at least one blowing nozzle orifice onto the fiber strands and draws the fiber strands, wherein the blowing stream is guided to the fiber strands inside an acceleration section, in which the fiber strands and the blowing stream are accelerated in such a manner that the fiber strands are drawn to form infinite microfibers. The present invention also provides a non-woven fiber and a resulting non-woven fabric produced according to the method.
[0012] The invention is based on the knowledge that in the conventional melt-blown methods, the blowing stream is accelerated, upon impinging on the fiber strand, to a maximum velocity. Therefore, the meeting of the blowing stream and the fiber strand results in a more or less sudden elongation of the fiber strands. This elongation leads to drafting and—optionally upon exceeding a maximum spinning draft—to tearing of the fibers. In order to avoid such overstressing of the fibers, the blowing stream is fed, according to the invention, to the fiber strands inside an acceleration section. In the acceleration section the blowing stream and the fiber strands are then accelerated together in such a manner that the fiber strands are drawn to form endless micro fibers. In this way overstressing the fiber strand while drawing can be avoided in an advantageous way. The maximum velocity of the blowing stream is not reached until the end of the acceleration section and leads to the desired total drawing of the fiber strands.
[0013] Since the blowing stream and the fiber strands are accelerated inside the acceleration section, the blowing stream can be fed to the fiber strands at a relatively low expenditure of energy. Thus, it has been demonstrated that merely an overpressure in a range below 1,000 mbar is sufficient to provide the fiber strands with the desired spinning draft. Consequently the consumption of the blowing stream can also be reduced to a minimum.
[0014] The blowing stream is preferably air that exhibits a natural air temperature in a range between 15° C. and 110° C. Thus, it is possible to quickly establish peripheral zones for the fibers, a feature that benefits in particular the stability of the fibers for drawing. In addition, the microfibers cool better. In this respect it is important that the air does not heat up. Therefore, the temperature that accepts the air without cooling or heating owing to the environmental conditions is called here the natural air temperature.
[0015] The blowing stream is produced preferably from the surrounding air at an ambient temperature. Said surrounding air is drawn in from the environment below the spinneret. At an average consumption of approximately 600 m 3 /h*m of surrounding air and at a maximum overpressure of 1 bar in a conventional spinning device, the blowing stream can be provided at a low cost.
[0016] Owing to the alternative method, with which the fiber strands are extruded at a mass flow of the polymer melt through the nozzle hole of the spinneret of 1.0 g/min. to 10 g/min. per nozzle hole, all of the current types of polymers, for example polypropylene or polyamide, may be extruded. Preferably a throughflow of >3 g/min. is set per nozzle hole. Therefore, the hole diameter may lie in a range between 0.2 and 1.0 mm.
[0017] Therefore, it is especially advantageous for the polymer melt to be heated inside the spinnerets just before emerging from the nozzle holes, so that the freshly extruded fiber strand exhibits a relatively high melting temperature that may be, for example, above 350° C. for a polypropylene fiber. Depending on the type of polymer, the polymer melt is heated preferably to a range between 300° C. and 400° C. in order to obtain a constant optimal setting as a function of the type of polymer, the capillary diameter of the nozzle holes and the desired fiber fineness, the length of the acceleration section for accelerating the blowing stream and the fiber strands ranges from 2 mm to 30 mm.
[0018] Thus, the fiber strands can be fed directly from the nozzle hole into the acceleration section or not until the fiber strands have passed through a short extrusion zone of a maximum 2 mm, in which the fiber strands may emerge from the nozzle hole without any influence of the blowing stream.
[0019] In order to generate high draft forces on the fiber strands, a preferred alternative of the method provides that the fiber strands and the blowing stream are fed, upon passing through the acceleration section, into a free space, where an atmosphere prevails that is in essence equal to an ambient pressure. The expansion of the blowing stream into the free space produces zones of turbulence, which improves the blowing stream's attack on the fiber surface. So-called whiplash effects may also occur with the result that the fibers continue to be drawn.
[0020] In order to intensify such effects, additional zones of air turbulence may be generated by air conductors inside the free space. This in turn also generates special effects in the fibers, such as thick and thin points.
[0021] However, there is also the possibility of providing an additional air stream inside the free space for the purpose of cooling. This alternative of the method is especially advantageous to implement in those cases, in which the blowing stream exhibits relatively high air temperatures.
[0022] The method, according to the invention, is suitable for processing all current types of polymers, such as polypropylene, polyethylene, polyester or polyamide, and to process into non-woven fibers with microfiber cross sections ranging up to 0.5 μm. In particular, good results could be attained with a polypropylene material, where the fiber fineness of the infinite microfibers was in a range between 1 μm and 30 μm.
[0023] The microfiber, produced with the method according to the invention, is suitable, as an infinite fiber, in particular for depositing in order to form a non-woven fabric.
[0024] The inventive device for carrying out the inventive method provides that an acceleration section is formed between the upper edges and the bottom edges of the two blowing nozzle orifices, which are arranged below the spinneret. Thus, there is no need for any additional aids in order to achieve an acceleration section, which is designed directly below the nozzle holes. The device, according to the invention, is characterized in particular in that a plurality of fiber strands can be drawn uniformly with relatively close spacing to form microfibers without the adjacent fibers conglutinating. Therefore, the device, according to the invention, is suitable for producing a large number of high quality microfibers of high uniformity.
[0025] According to an advantageous further development of the inventive device, the upper edge of the two blowing nozzle orifices is assigned to an entry throat; and the bottom edges of the two blowing nozzle orifices are assigned to an exit throat in order to achieve a defined acceleration section. The exit throat exhibits a free flow cross section that is smaller than the flow cross section of the entry throat. Thus, after the fibers have passed through the entry throat, they may be accelerated continuously by means of the blowing stream, emerging from the blowing nozzle orifices, as far as up to the exit throat.
[0026] Depending on the fiber fineness and the type of polymer, the exit throat is set to a slit width ranging from 2 to 8 mm. The slit width is defined by the smallest distance between the bottom edges that are opposite each other and belong to the blowing nozzle orifices.
[0027] The entry throat, which exhibits a larger slit width, can be formed advantageously directly on a level with the underside of the spinneret, so that the extruded fiber strands can enter directly into the acceleration section. However, there is the possibility of forming the entry throat at a short distance from the underside of the spinneret, so that the fiber strands do not reach the acceleration section until after passing through a short extrusion zone ranging from 0 to 2 mm.
[0028] The length of the acceleration section is defined by the distance of the entry throat from the exit throat. Depending on the type of fiber and the fiber fineness this length may range from 2 mm to 20 mm.
[0029] A preferred design of the inventive device exhibits an inflow channel for each blowing orifice for the air supply. Said inflow channel is formed between the bottom edge and the upper edge of the respective blowing nozzle. Therefore, the upper edge and the bottom edge are aligned or formed in such a manner that the inflow channel exhibits in the direction of the blowing orifice a tapering flow cross section on the end of the bottom edge and the upper edge respectively. Thus, a continuous acceleration of the supplied air as far as up to the entry into the acceleration section can be achieved so that a small supply of energy is necessary to generate the blowing stream.
[0030] The air that is made available is held advantageously in reserve in a pressure chamber that is connected to the blowing orifices.
[0031] According to an especially advantageous further development of the inventive device, the pressure chamber is connected to a suction unit in order to provide air as inexpensively as possible. This suction unit takes in the surrounding air and conveys it directly into the pressure chamber.
[0032] A free space is formed below the bottom edges of the blowing orifices in order to facilitate an intensive draft of the fiber strands during the expansion of the blowing stream upon emerging from the acceleration section.
[0033] The free space may contain additional aids for guiding, cooling and/or drawing the fibers. This gives the inventive device a high degree of flexibility that makes it possible to produce microfibers of any type and for any application.
[0034] The non-woven fiber, which is made of a polymer material and produced according to the method of the invention, is characterized in that, despite the microfiber cross sections ranging from 0.5 μm to 30 μm, the fibers exhibit an infinite length. This makes it possible to provide infinite microfibers, produced by a melt-blown method, in order to produce non-woven fabrics.
[0035] Thus, the inventive non-woven fabric, which is formed from the non-woven fibers of the invention, is characterized in particular by a high uniformity both in the machine direction and in the cross direction. Therefore, such non-woven fabrics are especially suitable for barrier products, where, on the one hand, permeability to air is desired, but, on the other hand, such a non-woven fabric exhibits a blocking effect with respect to liquids. Therefore, the inventive non-woven fabric is especially suitable for hygienic products, medical products and filter applications.
[0036] The inventive non-woven fabric is characterized in particular by a higher stretching ability as compared to conventional melt-blown non-woven fabrics. Therefore, the inventive non-woven fabric can be used advantageously in products, where minor deformations occur during production or use. In particular for such applications a suitable non-woven fabric is one, where the infinite microfibers, which are made of a polypropylene, are deposited to form a weight per unit of area in a range between 1.5 g/m 2 and 50 g/m 2 and lead to an elongation at break of at least 60% or can tolerate a maximum tensile stress at an elongation of at least 40%.
[0037] The high strength and deformability of the non-woven fabrics make it possible to produce in an advantageous manner composite non-woven fabrics that exhibit a plurality of layers. In the composite non-woven fabric of the invention, at least one of the layers is made of a non-woven fabric exhibiting the infinite microfibers of the invention.
[0038] Both the inventive non-woven fabric and the composite non-woven fabric are especially suitable for hygienic products, such as diapers, sanitary napkins, medicinal products, such as wound dressings, filter products, or household products, such as cleaning cloths or dust cloths.
[0039] Therefore, for the above applications in particular composite non-woven fabrics, wherein at least one other layer is made of a spun bond non-woven fabric, are preferably used.
BRIEF DESCRIPTION OF THE DRAWINGS
[0040] Having thus described the invention in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:
[0041] FIG. 1 is a schematic representation of a view of one embodiment of the inventive device for carrying out the inventive method;
[0042] FIG. 2 is a schematic representation of a view of a detail of the spinneret underside of another embodiment of the inventive device;
[0043] FIG. 3 is a schematic representation of a view of a detail of another embodiment of the inventive device;
[0044] FIG. 4 is a schematic representation of a longitudinal sectional view of another embodiment of the inventive device;
[0045] FIG. 5 is a diagram of the elongation as a function of the weight per unit of area of a non-woven fabric, according to the invention; and
[0046] FIG. 6 is a diagram of the tensile strength as a function of the weight per unit of area of a non-woven fabric, according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0047] The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the invention are shown. Indeed, the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.
[0048] FIG. 1 is a schematic representation of a view of a first embodiment of the inventive device for carrying out the inventive method.
[0049] The embodiment exhibits a spinneret 1 , which is connected to a melt source (not illustrated here) by means of a melt feed 2 . Usually an extruder is used as the melt source. Said extruder melts a thermoplastic material and feeds said material as the polymer melt under pressure to the spinneret. The underside of the spinneret 1 exhibits a plurality of nozzle holes 5 , which are connected inside the spinneret 1 to the melt feed 2 . The nozzle holes 5 are configured on the underside of the spinneret 1 in a specific arrangement, preferably in a series of rows with one or more rows next to one another. A fiber strand can be extruded out of the polymer melt emerging from each of the nozzle holes 5 .
[0050] Underneath the spinneret 1 there is a blower 3 , which exhibits two blowing nozzles 4 . 1 and 4 . 2 , which lie opposite each other and are located a short distance underneath the spinneret 1 . Each of the blowing nozzles 4 . 1 and 4 . 2 contains a blowing nozzle orifice 7 . 1 and 7 . 2 , which is formed between a respective upper edge 9 . 1 or 9 . 2 and the respective bottom edge 10 . 1 or 10 . 2 . The upper edge 9 . 1 and/or 9 . 2 and the bottom edge 10 . 1 and/or 10 . 2 are designed in the shape of plates and extend with their free end essentially parallel to the nozzle holes 5 of the spinneret 1 . Thus, the upper edges 9 . 1 and 9 . 2 , which lie opposite each other, form an entry throat; and the bottom edges 10 . 1 and 10 . 2 , which lie opposite each other, form an exit throat for the fiber strands 6 . The entry throat and the exit throat are designed in such a manner that between the upper edges 9 . 1 and 9 . 2 and the bottom edges 10 . 1 and 10 . 2 there is an acceleration section 15 , in which a blowing stream, emerging from the blowing nozzle orifice 7 . 1 and 7 . 2 , is accelerated together with the fiber strands 6 .
[0051] The upper edges 9 . 1 and 9 . 2 of the blowing nozzles 4 . 1 an 4 . 2 are usually arranged in such a manner with respect to the spinneret 1 that, on the one hand, no significant heat losses can occur at the spinneret 1 and, on the other hand, no blowing air can escape outside the acceleration section. The design (which is not shown in FIG. 1 ) of the transition from the spinneret 1 to the upper edges 9 . 1 and 9 . 2 shall be explained in detail below.
[0052] Each of the blowing nozzles 4 . 1 and 4 . 2 is assigned a pressure chamber 8 . 1 and 8 . 2 , in which is stored a blowing medium, which is held under an overpressure. Preferably air is used as the blowing medium. However, it is also possible to use a gas. The pressure chambers 8 . 1 and 8 . 2 may be connected jointly or separately to a pressure source, for example a compressed air ductwork system. Below the blower 3 there is a free space 12 that extends from the bottom edges 10 . 1 and/or 10 . 2 of the blowing nozzles 4 . 1 and 4 . 2 as far as to a depositing belt 13 . The depositing belt 13 serves to deposit the drawn microfibers 11 to form a non-woven fabric 14 . To this end, the depositing belt 13 is connected to a drive in order to carry away in a continuous mode the non-woven fabric 14 after the microfibers 11 have been deposited. The arrows show the direction of movement of the depositing belt 13 .
[0053] The embodiment (shown in FIG. 1 ) of the inventive device is shown in an operating situation. When in operation, the spinneret 1 is fed continuously a polymer melt, which is made, for example, of polypropylene. The spinneret 1 is designed so that it can be heated in order to hold the melt temperature of the polymer melt in a range above 300° C., preferably in a range between 300 and 400° C. Then the polymer melt is extruded through the nozzle holes 5 to form a respective fiber strand 6 . After the fiber strands 6 emerge from the nozzle holes 5 , they arrive in the acceleration section 15 and are brought together with a blowing stream. Thus, the fiber strands 6 and the blowing stream are accelerated continuously inside the acceleration section 15 as far as up to an exit throat. In this way the fiber strands 6 are increasingly stretched. The result is that following the expansion of the blowing stream in the free space, said fiber strands form microfibers with a fiber cross section in a range between 0.5 μm and 30 μm. Then the microfibers 11 are deposited continuously as the non-woven fabric 14 on the depositing belt 13 .
[0054] A cold blowing medium, preferably cold air, is used as the blowing medium for taking off and stretching the fiber strands 6 . This process allows the fiber strands to cool down until they are deposited, so that no additional cooling of the fibers is necessary. At air temperatures of, for example 25° C., in particular the free space 12 between the blower 3 and the depositing belt 13 can be held extremely small so that the blowing stream significantly improves the depositing of the microfibers so as to form a non-woven fabric. In addition, the stability of the fiber guide is enhanced in that, when the cold blowing air meets the freshly extruded fiber strands, rapid cooling of the peripheral zones of the fiber strands 6 takes place. However, the stretchability remains essentially preserved owing to the molten core areas of the fiber strands 6 .
[0055] In order to attain maximum draft forces by means of the blowing stream, the blowing nozzles 4 . 1 and 4 . 2 are formed preferably in such a manner that the blowing stream already flows out of the blowing nozzle orifices in the direction of travel of the fibers. To this end, FIG. 2 is a cross sectional view of another embodiment of the inventive device. This cross sectional view shows only a part of the spinneret underside with the underlying blowing nozzle orifices of the blowing nozzles.
[0056] The detail in FIG. 2 shows the emergence situation of a fiber strand 6 at the spinneret 1 in a cross sectional view. To this end, the spinneret 1 exhibits a nozzle hole 5 . The spinneret 1 has a number of heating elements 19 in order to heat the polymer melt, conveyed inside the spinneret 1 .
[0057] Below the spinneret 1 there are blowing nozzles 4 . 1 and 4 . 2 with blowing nozzle orifices 7 . 1 and 7 . 2 . The blowing nozzle orifice 7 . 1 is placed between the upper edge 9 . 1 and the bottom edge 10 . 1 . The upper edge 9 . 1 and the bottom edge 10 . 1 are designed as mold plates, which between themselves form the inflow channel 18 . 1 . The inflow channel 18 . 1 exhibits a flow cross section that tapers off in the direction of the blowing nozzle orifice 7 . 1 so that the blowing air, supplied inside the inflow channel 18 . 1 , is accelerated continuously as far as up to the blowing nozzle orifice 7 . 1 . At the same time the inflow channel 18 . 1 is shaped by the upper edge 9 . 1 and the bottom edge 10 . 1 in such a manner that the blowing stream, emerging from the blowing nozzle orifice 7 . 1 , is fed in the direction of travel of the fibers. It has proven to be especially advantageous if the upper edge 9 . 1 in relation to the bottom edge 10 . 1 exhibits such a physical curvature that its theoretical imaginary extension that projects beyond the free end strikes in the middle of an exit throat 17 , which is formed by the bottom edges 10 . 1 and 10 . 2 , which lie opposite each other. At the same time, the continuous decrease in the distance between the upper edge 9 . 1 and the bottom edge 10 . 1 continues as far as up to the middle of the exit throat 17 . This design of the blowing nozzle 4 . 1 makes it possible to improve the accelerating effect for drawing off the fiber strand.
[0058] The blowing nozzle orifice 7 . 2 of the blowing nozzle 4 . 2 on the opposite side of the spinneret 1 is identical (as the mirror-image) to the first blowing nozzle orifice 7 . 1 of the blowing nozzle 4 . 1 . The inflow channel 18 . 2 between the formed plates of the upper edge 9 . 2 and the bottom edge 10 . 2 is configured with a tapering flow cross section. Thus, with respect to a more detailed description reference is made to the aforesaid.
[0059] The upper edges 9 . 1 and 9 . 2 are spaced apart so as to lie opposite each other below the underside of the spinneret 1 and form an entry throat 16 . The slit width of the entry throat 16 is labeled with the capital letter E in FIG. 2 and defined by the distance between the two upper edges 9 . 1 and 9 . 2 . The slit width E is essentially constant over the entire spinning width of the spinneret 1 .
[0060] Below the upper edges 9 . 1 and 9 . 2 the bottom edges 10 . 1 and 10 . 2 are arranged so as to lie opposite each other in relation to the exit throat 17 . The slit width of the exit throat 17 is labeled with the capital letter A in FIG. 2 and is defined by the narrowest distance between the two bottom edges 10 . 1 and 10 . 2 . The slit width A of the exit throat 17 is also in essence constant over the entire spinning width of the spinneret 1 . The slit width A of the exit throat 17 is designed smaller than the slit width E of the entry throat 16 . Between the entry throat 16 and the exit throat 16 there is an acceleration section 15 . In particular, through the inflow channels 18 . 1 and 18 . 2 , which belong to the blowing nozzles 4 . 1 and 4 . 2 and which empty directly into the acceleration section 15 , the fiber strand 6 together with the blowing air is guided from the entry throat 16 with increasing velocity along the acceleration section 15 as far as up to the exit throat 17 and blown into the free space 12 , which is formed below the exit throat 17 . The distance between the entry throat 16 and the exit throat 17 , which defines directly the exit cross section of the blowing nozzle orifices 7 . 1 and 7 . 2 and gives the length of the acceleration section 15 , may range from 2 mm to 30 mm as a function of the type of polymer and fiber fineness. The split width of the exit throat 17 varies from 2 mm to 8 mm. Even if the nozzle holes 5 exhibit a capillary diameter of 0.6 mm, microfibers exhibiting a fiber fineness in a range between 1 and 30 μm could be produced with the device of the invention.
[0061] On the side of the blowing nozzles 4 . 1 and 4 . 2 that faces the spinneret 1 , a sealant 23 . 1 and 23 . 2 is disposed between the spinneret 1 and the upper edges 9 . 1 and 9 . 2 . The sealants 23 . 1 and 23 . 2 form, on the one hand, in relation to the spinneret 1 an insulating layer in order to avoid heat losses and, on the other hand, a seal with respect to the blowing air, conveyed in the acceleration section 15 . The sealants 23 . 1 and 23 . 2 are made preferably of insulating materials.
[0062] In the embodiment of the inventive device, depicted in FIG. 2 , there is space between the underside of the spinneret 1 and the acceleration section 15 . The result of this space is that the fiber strands 6 do not enter the acceleration section until after they have passed through a short extrusion zone. Such a reverse movement leads to an additional stability with respect to the travel of the fiber strands.
[0063] However, it is also possible to let the extruded fiber strands 6 pass into the acceleration section 15 directly after leaving the nozzle holes 5 . Such an embodiment of the inventive device is depicted as a schematic representation in a sectional view in FIG. 3 . The design of the spinneret 1 as well as of the blowing nozzles 4 . 1 and 4 . 2 is in essence identical to the above embodiment, according to FIG. 2 , so that reference is made to the above description, and only the differences are explained.
[0064] The entry throat 16 between the upper edges 9 . 1 and 9 . 2 is constructed directly on a level with the underside of the spinneret 1 . The result is that upon leaving the nozzle hole 5 , the fiber strands 6 enter directly into the acceleration section 15 and make contact with the blowing stream and thus acquire from the spinneret 1 a different take-off behavior.
[0065] On the side of the blowing nozzles 4 . 1 and 4 . 2 that faces the spinneret 1 , there is one respective air gap 24 . 1 and 24 . 2 between the spinneret 1 and the upper edges 9 . 1 and 9 . 2 . The air gaps 24 . 1 and 24 . 2 are dimensioned so closely that in essence no blowing air can pass through, but a sufficient layer of air remains in order to insulate it from the spinneret 1 .
[0066] In order to improve and increase the drawing of the microfibers 11 , the free space 12 in the embodiment, depicted in FIG. 3 , has a number of conductors 20 , which result in the formation of a plurality of turbulence zones and, thus, effect an intensification of the drawing process. However, this enables the production of even preferably microfibers with special effects, such as thin points.
[0067] FIG. 4 shows a schematic representation of a longitudinal sectional view of another embodiment of the device of the invention. The embodiment, according to FIG. 4 , is in essence identical to the embodiment according to FIG. 1 , so that only the differences are explained below, and otherwise reference is made to the above description.
[0068] In the embodiment, depicted in FIG. 4 , the blower 3 exhibits a suction unit 21 below the spinneret 1 . The suction unit 21 is connected to the pressure chambers 8 . 1 and 8 . 2 . The suction unit 21 takes in the surrounding air from below the spinneret 1 and feeds it to the pressure chambers 8 . 1 and 8 . 2 . In this way, the blowing stream for drawing the fiber strands can be produced advantageously from the surrounding air. Thus, the surrounding air exhibits a room temperature that may range, as a function of the surroundings, from 15° C. to 40° C. Thus, the result is that the blowing stream can be provided and produced at a very low cost.
[0069] The embodiment, depicted in FIG. 4 , exhibits an injector 22 in order to further improve the guide of the fibers below the blowing nozzles 4 . 1 and 4 . 2 in the free space 12 .
[0070] Therefore, when the fiber strands pass through the injector 22 , the surrounding air pending in the free space 12 from the surrounding, is directly involved without any outside assistance in the guiding and cooling of the fibers. However, it is also possible for climate-controlled air to be drawn into the free space 12 . Then, as the conditioned air, the climate-controlled air can be predetermined with respect to the air temperature, humidity and air quantity so that specific cooling conditions at the fibers can be set. However, such mechanisms are used preferably in those cases, in which the blowing stream must be produced from a relatively warm air.
[0071] In principle, the inventive method and the inventive device for carrying out the inventive method are suitable for use with polymer melts of all current polymers, such as polyester, polyamide, polypropylene or polyethylene.
[0072] In one example of the method, a polymer, which is made of a polypropylene, is melted to form a melt and extruded through a nozzle hole having a capillary diameter of 0.6 mm and a melt throughput of 6 g/min. per nozzle hole. The number of nozzle holes was 36 . The pressure chambers 8 . 1 and 8 . 2 were supplied with air at room temperature and an overpressure of 260 mbar. Therefore, the configuration of the device, depicted in FIG. 2 , was used in order to draw the extruded fiber strands so as to form microfibers. After extruding and drawing, the PP microfibers were deposited to form a non-woven fabric with a weight per unit of area of 50 g/m 2 . An analysis of a non-woven fabric sample revealed a fiber fineness of the microfiber in a range between 2.5 and 25.1 μm. The average fiber cross section of the microfibers was 5.2 μm. The subsequent determination of the elongation at break of a non-woven fabric sample, which was 40 mm long, yielded a value of 63% in the machine direction and 70% in the cross direction. At the same time a maximum tensile strength of 29 N in the machine direction and 17 N in the cross direction could be determined. Therefore, in comparison with conventional melt-blown non-woven fabrics with finite fiber pieces, an approximately 300% improvement in the physical properties could be determined.
[0073] In a series of experiments the polypropylene fibers were deposited to form non-woven fabric that exhibited a variety of different weights per unit of area. The results are plotted in the diagram in FIG. 5 and FIG. 6 . The diagram, shown in FIG. 5 , shows the relationship between the weight per unit of area of the non-woven fabric and the attained elongation at break. The capital letters MD and CD designate the orientation of the non-woven material, where MD (machine direction) stands for the machine direction and CD (cross direction) stands for the cross direction in the non-woven fabric. As the weight per unit of area decreases, the elongation at break increases, an effect that indicates in particular the high strength of the infinite microfibers. Compared to the conventional melt-blown non-woven materials, an increase of up to 300% with respect to the elongation at break could be determined.
[0074] FIG. 6 shows a diagram of the tensile strength of the non-woven fabric as a function of the weight per unit of area. Here, too, a significant increase over the conventional melt-blown non-woven fabrics could be determined. The maximum tensile strength was above 5 N for non-woven materials with a weight per unit of area of about 10 g/m 2 and above 25 N for non-woven materials with a weight per unit of area of about 50 g/m irrespective of the direction of pull. Therefore, such non-woven materials are especially suitable for applications, where deformations, such as in hygienic materials, must be tolerated, or where deformations occur during production. The microfiber characteristics of the non-woven fabric, according to the invention, result, on the one hand, in an air and/or vapor permeability with a simultaneous low penetration tendency. Thus, the non-woven materials can be used preferably as barrier products, such as in the hygiene sector for diapers and sanitary napkins. However, applications in medical technology, such as wound dressings, are also possible.
[0075] The non-woven fabrics, made of such fibers, may be included in an especially advantageous manner in composite materials. The suction capability and blocking effect of such non-woven fabrics may be used advantageously in a composite non-woven fabric in order to form a barrier layer.
[0076] The significantly high elongation and tensile strength of the inventive melt-blown method also lead to improved processing. Even applications with small deformation, such as in hygienic products, are possible without any problems.
[0077] Many modifications and other embodiments of the invention set forth herein will come to mind to one skilled in the art to which this invention pertains having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
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A meltblown method for melt spinning fine non-woven fibers and a device for carrying out said method. According to the invention, a polymer melt is extruded, in order to form several fiber strands, through several nozzle bores of a spinning nozzle and twisted on the outlet side of the nozzle bores by means of a cold blow flow. According to the invention, the blow flow is fed to the fiber strands in an acceleration path wherein the fiber stands and the blow flow are accelerated in such a manner that the fiber strands are twisted in order to form continuous fine fibers. According to the inventive device, the inventive acceleration path is formed between the upper edges and the lower edges of the two blow nozzle openings below the spinning nozzle.
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[0001] This application claims the benefit of U.S. Provisional Application No. 62/016,138 filed on Jun. 24, 2014.
BACKGROUND
[0002] The present invention relates to filter media cartridges used in air filtering systems, particularly industrial air filtering systems.
[0003] Air filtering systems are commonly used in numerous industrial applications. Typically, air filter systems draw air from the surrounding environment, pull that air through one or more filters and then expel the filtered air back into the surrounding environment. The filters used can have many shapes, but are typically either flat or tubular. The tubular filters typically draw air through the exterior of the filter into the interior. The filter captures contaminants that are entrained in the air and the filtered air exits the air filter system.
[0004] As the filter begins to accumulate contaminants, it is necessary to clean the filter media. One method of cleaning the filter is to pulse compressed air in the interior of the tubular filter media and blow the contaminants off the media. The contaminants are then collected in a pan and discarded.
[0005] One disadvantage of known filter media is the inability to withstand the drawing of air through the media to filter the air and the cleaning of the filter by pulsing compressed air through the filter media. The pressures used are high and results in undue flexing of typical filter media. After repeated flexing, the filter media can break down in numerous ways, such as for example folding upon itself, which reduces the filtration area, tearing which results in an inability to filter, etc.
[0006] The present invention overcomes these disadvantages by providing a unique filter media cartridge that has reinforced pleats that withstand repeated pressure changes, a central support to withstand repeated pressure changes and support ribs to add additional overall strength to the filter media.
[0007] The invention will become more apparent to those skilled in the art from the detailed description of a preferred embodiment. The drawings that accompany the detailed description are described below.
DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is an exploded view of the filter media cartridge of the present invention.
[0009] FIG. 2 is a plan view of the filter media cartridge of the present invention.
[0010] FIG. 3 is a cutaway view of the filter media cartridge of the present invention taken along line A-A of FIG. 1 .
[0011] FIG. 4 is a cutaway view of the filter media cartridge of the present invention taken along line C-C of FIG. 1 .
[0012] FIG. 5 is an enlarged section of the filter media cartridge of the present invention.
[0013] FIG. 6 is a perspective view of an example of a air filtration unit incorporating filter media of the present invention.
[0014] FIG. 7 is a block diagram illustrating the method of making the filter media of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0015] With reference to FIGS. 1 and 2 , the filter media cartridge of the present invention is shown generally at 10 . The filter cartridge 10 includes a filter media 12 mounted between a top pan 14 and a bottom pan 16 . The pans 14 and 16 hold the media in position and facilitate installation of the filter media cartridge 10 within an air filter unit. Retention bands 18 are mounted about the filter media to retain the media 12 in position. This is particularly important when compressed air is pulsed through the media 12 in a reverse direction. Without the restraint of the bands 18 , the filter media 12 would be blown outwards away from the internal support core 20 during a compressed air pulse, which can cause damage, ripping or tearing to the media 12 , allowing pollutants, particulate or dirt through the filter, compromising its filtration efficiency. In the disclosed embodiment, the bands 18 are mounted to the filter media 12 by adhesive.
[0016] To provide additional support, internal support core 20 is provided. The internal support core 20 adds additional support to the filter media cartridge, extending the media's life during operation and cleaning. The internal support core 20 in the disclosed embodiment is expanded metal. As is well known to those of ordinary skill in the art, the expanded metal is formed by making numerous cuts or slits in the metal and then stretching or expanding the metal to form enlarged openings at the various cuts. The expanded metal is shown schematically at 21 in FIG. 2 . Ribs 23 are provided along the length of the core 20 and are formed by leaving portions of the expanded metal core 20 free from cuts. The ribs 23 form a continuous spiral support along the length of the internal support core 20 .
[0017] The filter media 12 of the present invention includes a glue bead 22 that provides spacing between the folds of the media 12 and reinforces the media 12 . The glue bead 22 is positioned along the interior of the media 12 adjacent the internal support core 20 . In the disclosed embodiment, the glue bead is formed in at least one strip along the internal circumference of the media 12 , and in the preferred embodiment, along the top and bottom of the media 12 . In the even more preferred embodiment, the glue bead 22 is formed at spaced locations along the length of the media 12 . The glue bead 22 is applied in a strip along the media 12 prior to the media being folded. When the media 12 is folded, the glue adheres adjacent folds together along the interior of the media 12 .
[0018] The glue beads 22 provide substantial support and regular spacing to the folds of the media 12 . This prevents the folds and pleats of the media 12 from collapsing against one another when under negative pressure from the airflow being drawn through the media 12 . This means the entire surface area of the media 12 is exposed and able to be effectively utilized by the airstream passing through the filter, to evenly distribute the captured contaminants, and to reduce the level of pressure drop and resistance to the airflow created by the media 12 and the captured particulate layer, also known as the dust cake.
[0019] With reference to FIG. 7 , a block diagram representation of the method of making the filter media of the present invention is illustrated. In the preferred method of making the filter of the present invention, a flat sheet of filter material 12 is fed into a pleating machine 50 . The pleating machine creases the filter material to form the folds or pleats. In the disclosed embodiment, the creases are spaced apart at approximately 2 inch intervals along the length of the filter material. The creases create a series of peaks and valleys along the length of the filter material. These pleats or folds are approximately 2 inches deep.
[0020] After being creased, the filter material exits the pleating machine and enters the glue bead machine 52 . The glue bead machine 52 has a number of spaced glue nozzles 54 . In the disclosed embodiment the glue nozzles 54 are approximately on 8 inch centers to apply multiple glue beads along the length of the creased filter material sheet 12 . As the sheet enters and progresses through the glue bead machine 52 , the filter material 12 begins to unfold allowing the glue to the applied along the peaks and valleys of the sheet. The glue bead is generally applied in a continuous strip along the length of the filter medium 12 . Depending upon the filter medium, a plurality of glue strips are spaced along the width of the filter medium and extend along the length of the filter medium.
[0021] Upon exiting the glue bead machine 12 , the sheet is forced to fold at the creases. A stop bar 56 is used to stop the forward movement of the filter medium 12 , which causes the filter medium to fold as it exits the glue bead machine 52 . As the filter media 12 folds, adjoining peaks and valleys contact one another with the glue bead strip at the adjoining peaks and valleys adhere to bond the peaks and valleys together at that location. The filter medium is than allowed to cure to form a pleated sheet with peaks and valleys with the adjoining peaks glued together at spaced locations along the width of the filter medium. After curing, the sheet of filter medium is cut to a desired length and formed into a tube. The glue is flexible enough to allow the media to be formed into a tube and have the peaks fan out.
[0022] In the disclosed embodiment, glue, in this application a two part curing adhesive is applied to the ends of the tube 12 and to the end caps 14 and 16 . The end caps 14 and 16 can then be secured to the ends of the tube 12 . Additionally, the core 20 is adhered to the ends caps 14 and 16 by the same adhesive.
[0023] As will be appreciated by those of ordinary skill in the art, either the top pan 14 or bottom pan 16 or both have open centers to allow the filtered air to flow through the cartridge 10 . In the disclosed embodiment, the top and bottom pans 14 and 16 and the core 20 are attached to the media 12 by the two part adhesive.
[0024] With reference to FIG. 6 , an example of an air filtration unit is generally illustrated at 30 . The air filtration unit has a housing 32 . The filter media cartridges 10 of the present invention are mounted in the housing 32 . A fan 34 and motor 36 draw air through an intake 38 . The air that is drawn in is pulled through the filter media cartridges 10 . The air has entrained particulates that are trapped in the filter media cartridge 10 . The air that is pulled through the media 12 then is expelled to through the outlet 40 .
[0025] Valves and nozzles can be used to pulse compressed air in reverse through the filter media cartridges 10 to blow off the particulates that have been trapped in the filter media 12 . The particulate that is blown off the media 12 is deposited in the container 42 . The container 42 can then be emptied.
[0026] The foregoing invention has been described in accordance with the relevant legal standards, thus the description is exemplary rather than limiting in nature. Variations and modifications to the disclosed embodiment may become apparent to those skilled in the art and do come within the scope of the invention. Accordingly, the scope of legal protection afforded this invention can only be determined by studying the following claims.
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A filter media cartridge and method of making filter media wherein the filter media has a plurality of folds formed into a tube with an internal support core supporting the media material. A plurality of retention bands mounted about the filter media to retain the filter media in position and prevent media from expanding outwardly sufficiently to damage the filter media. At least a one glue bead located circumferentially about the filter media. The glue bead adhering adjacent folds of the media together to provide support and regular spacing of the folds so that the folds are prevented from collapsing with respect to one another.
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The present invention incorporates by reference the material in the ASCII text file whose name is sample sequence listing, the date of creating the ASCII text file is 29 Dec. 2015, and the size of the ASCII text file is 2552 bytes.
The methylomonas referred to as SP.ZR1 has the China General Microbiological Culture Collection Center (CGMCC) designation number CGMCC NO. 9873, having been deposited on Oct. 29, 2014.
The address of CGMCC: No. 3, No. 1, Beichen West Road, Chaoyang District, Beijing
The telephone number:0086-10-64807355
The e-mail: cgmcc@im.ac.cn
FIELD OF THE INVENTION
The present invention relates to the art of application technology about microorganisms, and particularly relates to a high concentration methanol tolerant methanotroph and its application.
DESCRIPTION OF THE RELATED ART
The world possesses a huge amount of methane, which is mainly in Siberia Marsh (about 8 ten billion tons), in the Polar Ice Sheet (about five hundred billion tons) and in the Sea Bed (about 2.5 to 10 megatons), meanwhile, there are a lot of unconventional sources of methane on earth, such as coalbed methane, landfill gas, biogas, marine methane hydrates and methane recovered from the coke oven gas and refinery gas. Methane is a greenhouse gas whose warming power of the atmosphere is 23 times stronger than carbon dioxide. Currently methane is used as fuel by human primarily. Converting methane into higher value chemicals and liquid fuels can provide significantly economic value, and environmental and strategic interests.
Currently conversion process of methane is indirect in industry, which mainly includes three steps. They are complex and multistage processes, and are operated under severe conditions such as: steam reforming at 800˜1000° C., and 20˜30 ATM; partly oxidizing at 1200˜1500° C. and methanol synthesizing at 200˜300° C. and 50˜100 ATM. While microorganisms can convert methane into various metabolic intermediates with different carbon chain length at room temperature and atmospheric pressure, a biotechnology of converting microorganisms into methane has good potential and prospect.
Commercial bioconversion of methane has gone through three stages: 1) producing single cell protein, 2) using methane monooxygenase to produce ethylene oxide, and 3) biodegradating chloride contaminants. Meanwhile, only using methane monooxygenase to produce ethylene oxide has achieved a certain economic benefits until now. An important factor of limiting the industrialization of converting methane by using microorganisms is low growth rate of the microorganisms.
Methanol is the main product of methane conversion process, and is the main product of coal chemical industry. Methanol is also the basic material of C 1 chemical industry. Methanol has wide raw material sources, and its biggest usage is to produce other oxygen-containing organic chemicals, such as formaldehyde, acetic acid and ether. The research for biological conversion of methanol is still at the laboratory stage. Producing single cell protein by fermenting which uses methanol as substrate is the most typical application of biotechnology in the development of methanol derived product. Methanol can be directly used by methanotroph, but methanol has a relatively strong physiological toxicity to methanotroph. Methanotrophs which have been reported show poor ability to tolerate methanol. For example, Methylomonas lenta exhibits sensitiveness to culture medium added with 0.1% to 0.5% methanol. The methanotroph which has been mutagenized can tolerate 2.4% methanol, but shows poor stability. While the methanotroph disclosed by the present invention which is wild without being mutagenized can still grow when the concentration of methanol in culture medium reaches 3.5%.
At present, the patents about methanotroph in China mainly relate to cultural method of methanotroph, application of methanotroph in wastewater treatment, production of single cell protein and production of methanol. Parts of the patents have disclosed producing PHA by fermenting of methanotroph.
The methanotroph disclosed by the present invention can grow efficiently using methane, and can tolerate to high concentration of methanol. A good foundation is established for using the methanotroph to ferment methane or methanol to produce high value-added products such as carotenoids and polysaccharides.
SUMMARY OF THE INVENTION
One purpose of the present invention is to disclose a high concentration methanol tolerant methanotroph. The methanotroph disclosed by the present invention is screened from wetlands of sludge, and the methanotroph can grow rapidly by using methane, and the methanotroph can tolerate with high concentration of methanol.
Further, one purpose of the present invention is to provide an application of a high concentration methanol tolerant methanotroph. The methanotroph disclosed by the present invention can produce carotenoids in liquid fermentation culture medium with methanol or methane as substrate.
Further, one purpose of the present invention is to provide an application of a high concentration methanol tolerant methanotroph. The methanotroph disclosed by the present invention can produce polysaccharide in liquid fermentation culture medium with methanol or methane.
To achieve the above objects and other objects, the present invention adopts the technical scheme, the present invention provides:
A high concentration methanol tolerant methanotroph named Methylomonas sp. ZR1, an accession number of the methanotroph in China General Microbiological Culture Collection Center of the methanotroph is CGMCC No. 9873, and deposit date of the methanotroph is Oct. 29, 2014.
An application of the high concentration methanol tolerant methanotroph is for producing carotenoids.
Preferably, the carotenoids is produced by fermentation product which is obtained from inoculating and fermenting the methanotroph with methane or methanol as substrate in a fermentation temperature of 20˜30° C.
Preferably, the fermentation temperature is 25° C.
Preferably, when the methanol is used as substrate, the mass percent concentration of the methanol in the fermentation culture medium is less than or equal to 3.5%.
An application of the high concentration methanol tolerant methanotroph is for producing polysaccharide.
Preferably, polysaccharides are produced by the fermentation product, which is obtained from inoculating and fermenting of the methanotroph with methane or methanol as substrate in a fermentation temperature of 20˜30° C.
Preferably, the fermentation temperature is 25° C.
Preferably, when the methanol is used as substrate, the mass percent concentration of the methanol in the fermentation culture medium is less than or equal to 3.5%.
Preferably, the polysaccharide is heteropolysaccharide which mainly includes glucosamine, glucose and mannose.
Morphological characteristics of colonies of the methanotroph which is disclosed by the present invention are as follows:
circular smooth colonies with central uplift and smooth edges are generated on NMS culture medium, the colonies of the methanotroph show brightly orange and thick, Gram staining of the cells of the methanotroph is negative.
The beneficial effects of the present invention are as follows:
The advantages the methanotroph disclosed by the present invention are as follows:
{circle around (1)} being easy to cultivate: the methanotroph can grow well in NMS culture medium with methane as carbon source, wherein recipe of the NMS culture medium is simple, wherein there is no need to add organic nitrogen into the NMS culture medium;
{circle around (2)} growing rapidly with methane as carbon source: single colony of the methanotroph is picked and inoculated into the NMS culture medium with methane as substrate and with inorganic as nitrogen source; after being cultured for 48 h, the cell concentration of the methanotroph can reach 10 8 cfu/ml;
{circle around (3)} tolerating with high concentration of methanol: the methanotroph can grow well in the NMS culture medium with methanol as substrate, wherein concentration of methanol is 35 g/L; after being cultured for 3 days, OD 600 of the NMS culture medium can reach 2.5;
{circle around (4)} producing carotenoids and polysaccharides with methane and methanol as substrates:
After being cultured for 10 days with methane as substrate, fermentation broth of the methanotroph appears to be bright orange viscous liquid because of carotenoids and polysaccharides produced by the methanotroph;
After being cultured for 3 days with methanol as substrate, fermentation broth of the methanotroph appears to be bright orange viscous liquid because of carotenoids and polysaccharides produced by the methanotroph;
As described above, a high concentration methanol tolerant methanotroph Methylomonas sp. ZR1 is obtained by screening in the present invention, and the methanotroph Methylomonas sp. ZR1 can use methane to grow rapidly, and can use C 1 compounds such as methane and methanol to produce high value-added products such as carotenoids and polysaccharides. The methanotroph Methylomonas sp. ZR1 has good potential and prospect in biological transformation of C 1 compounds. The methanotroph Methylomonas sp. ZR1 disclosed by the present invention is applied to produce polysaccharide and carotenoids, wherein the producing process is simple and the operation of the producing is easy. The methanotroph Methylomonas sp. ZR1 can grow rapidly by using methane or methanol, and can produce carotenoids and polysaccharides with high added value. Meanwhile the methanotroph Methylomonas sp. ZR1 can tolerate with high concentration of methanol and has a high industrial application value.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a growth curve of the high concentration methanol tolerant methanotroph Methylomonas sp. ZR1 disclosed by the present invention with methane as substrate.
FIG. 2 is a growth comparison chart of the high concentration methanol tolerant methanotroph Methylomonas sp. ZR1 disclosed by the present invention with different concentration of methanol as substrate.
FIG. 3 is an absorption spectrum by full wave scanning of pigment extracted from fermentation product, which is produced by the high concentration methanol tolerant methanotroph Methylomonas sp. ZR1 during fermenting to produce carotenoids with methane as substrate in embodiment 4 of the present invention.
FIG. 4 is an absorption spectrum by full wave scanning of pigment extracted from fermentation product, which is produced by the high concentration methanol tolerant methanotroph Methylomonas sp. ZR1 during fermenting to produce carotenoids with methane as substrate in embodiment 5 of the present invention.
FIG. 5 is an absorption spectrum by full wave scanning of pigment extracted from fermentation product, which is produced by the high concentration methanol tolerant methanotroph Methylomonas sp. ZR1 during fermenting to produce carotenoids with methane as substrate in embodiment 6 of the present invention.
FIG. 6 is a HPLC spectrum of hydrolysate extracted from fermentation product, which is produced by the high concentration methanol tolerant methanotroph Methylomonas sp. ZR1 during fermenting to produce polysaccharide with methane as substrate in embodiment 7 of the present invention.
FIG. 7 is a HPLC spectrum of hydrolysate extracted from fermentation product, which is produced by the high concentration methanol tolerant methanotroph Methylomonas sp. ZR1 during fermenting to produce polysaccharide with methane as substrate in embodiment 8 of the present invention.
FIG. 8 is a HPLC spectrum of hydrolysate extracted from fermentation product, which is produced by the high concentration methanol tolerant methanotroph Methylomonas sp. ZR1 during fermenting to produce polysaccharide with methane as substrate in embodiment 9 of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be further described in detail with the accompanying drawings, to make those skilled in the art can implement the invention according to the text of the specification.
If there is no special instruction, experimental methods used in the following embodiments are conventional methods.
If there is no special instructions, materials and reagents used in the following embodiments can be obtained from commercial sources.
The solvent in the NMS culture medium is water, and the solute in the NMS culture medium is KNO 3 1 g/L, KH 2 PO 4 0.717 g/L, Na 2 HPO 4 0.272 g/L, MgSO 4 .7H 2 O 1 g/L, CaCl 2 .6H 2 O 0.2 g/L, sodium iron EDTA 0.005 g/L and 1 ml of trace element solution; when methane is used as carbon source or substrate, the methane accounts for 15˜50% of gas and air accounts for 50˜80% of gas; when methanol is used as carbon source or substrate, the adding content of the methanol is 1.0˜3.5%.
Solid medium is prepared by adding 15 g of agar per liter of the NMS culture medium.
The trace element solution is prepared by adding EDTA 0.5 g, FeSO 4 .7H 2 O 0.2 g, H 3 BO 3 0.03 g, ZnSO 4 .7H 2 O 0.01 g, MnCl 2 .4H 2 O 0.003 g, CoCl 2 .6H 2 O 0.02 g, CuSO 4 .5H 2 O 0.1 g, NiCl 2 .6H 2 O 0.002 g and Na 2 MoO 4 0.003 g per liter of water.
Embodiment 1
Screening Method of Methanotroph Methylomonas sp. ZR1
The methanotroph Methylomonas sp. ZR1 is screened from wetland of sludge, 1 g sample of wetland of sludge is inoculated directly into 250 ml anaerobic bottle containing 100 ml of the NMS culture medium, 100 ml of methane is added to the anaerobic bottle as carbon source to make methane account for 30% of gas phase in the anaerobic bottle. The methanotroph is cultured in shake at 25° C. and at 180 rpm until that OD 600 of the NMS culture medium can hold steady. The methanotroph is inoculated into fresh culture medium with 1% inoculation, and is subcultured 3 times; the liquid culture is diluted and coated on coated tablet, and the coated tablet is placed in air with methane accounting for 30%. A large amount of the methanotroph can be obtained by using the screening method, wherein the methanotroph Methylomonas sp. ZR1 which generates bright orange colonies grows fastest and generates the largest colony.
Genome of the methanotroph is extracted, and 16S rRNA gene sequences of the genome are amplified and sequenced; polynucleotide sequences of 16S rRNA are the same as polynucleotide sequence of SEQ ID No:1; with the 16S rRNA gene sequences compared with the Blast results in NCBI, the comparison results show that the 16S rRNA gene sequences have a 97.9% similarity with Methylomonas methanica S1 T ; according to the comparison results combined with physiological and biochemical characteristics of methanotroph Methylomonas sp. ZR1, the methanotroph is assigned as Methylomonas sp ZR1.
Embodiment 2
Methanotroph Methylomonas sp. ZR1 Growing with Methane as Substrate
Single colony of the methanotroph Methylomonas sp. ZR1 formed on the plate is picked, inoculated into 30 ml of NMS liquid culture medium (using methane as carbon source) to culture at 28° C. and at 180 rpm; samples of fermentation broth are taken and cell concentration of the samples is measured every day; as shown in the FIG. 1 , the cell concentration increases with the extension of fermentation time, which shows the number of the methanotroph Methylomonas sp. ZR1 gradually increases and the methanotroph Methylomonas sp. ZR1 grow well in the NMS liquid culture medium with methane as substrate.
Embodiment 3
Methanotroph Methylomonas sp. ZR1 Growing with Methanol as Substrate
Single colony of the methanotroph Methylomonas sp. ZR1 is obtained by the methanotroph Methylomonas sp. ZR1 growing with methanol as substrate, the single colony of the methanotroph Methylomonas sp. ZR1 is inoculated into 30 ml of NMS liquid culture medium (using methane as carbon source) to culture at 28° C. and at 180 rpm. After being cultured for 2 days, OD 600 of the NMS liquid culture medium reaches 0.7, inoculated into 100 ml of fresh NMS culture medium with 5% inoculation, wherein the content of methanol in the fresh NMS culture medium is respectively 12.5 g/L, 15 g/L, 17.5 g/L, 20 g/L, 22.5 g/L, 25 g/L, 27.5 g/L, 30 g/L, 32.5 g/L and 35 g/L, and be cultured in shake for 3 days at 25° C. and at 180 rpm in a 250 ml shake flasks; cultivation results are shown in FIG. 2 , which show the methanotroph Methylomonas sp. ZR1 can grow and reproduce well in the culture medium with different concentration of methanol.
Embodiment 4
Fermenting Methanotroph Methylomonas sp. ZR1 to Produce Carotenoids with Methane as Substrate
Single colony of the methanotroph Methylomonas sp. ZR1 formed on the plate is picked, inoculated into 30 ml of NMS liquid culture medium (using methane as carbon source) to culture at 25° C. and at 180 rpm, after being cultured for 2 days, OD 600 of the NMS liquid culture medium reaches 0.7, and inoculated into fresh NMS culture medium with 5% inoculation, fermenting in column reactor at 28° C.; after being cultured for 2 days, fermentation broth of single colony of the methanotroph Methylomonas sp. ZR1 appears to be orange viscous liquid; the methanotroph Methylomonas sp. ZR1 is collected by centrifugation for 10 mins at 8000 rpm; the methanotroph Methylomonas sp. ZR1 collected is washed twice with distilled water, vacuum freeze-dried, then dried powder of the methanotroph is obtained; the dried powder of the methanotroph Methylomonas sp. ZR1 is weighed, and is extracted 3 times with methanol solution whose volume is 10 times the volume of dried powder of the methanotroph Methylomonas sp. ZR1, then orange extraction solution of pigment is obtained; the orange extraction solution of pigment is filtered, and spin dried by a rotary evaporation apparatus, then red pigment is obtained.
The Color Reaction of the Red Pigment in Concentrated Sulfuric Acid
The extracted red pigment is re-dissolved in 1 ml of dichloromethane, then pigment solution is obtained; 50 μl of the pigment solution was taken, diluted with chloroform to 0.5 ml, and being added with a few drops of concentrated sulfuric acid; then the pigment solution turns from red to blue-green, which shows that the red pigment extracted is carotenoids.
Full wave scanning of the red pigment is taken; 300 μl of the pigment solution is taken, and is added into a quartz 96-well plate; while 300 μl of dichloromethane solution is kept as control, the pigment solution is scanned from 220 nm to 700 nm, the scan results are shown in FIG. 3 .
The scan results show a three-finger peak which is a typical characteristic peak of carotenoid appears at around 500 nm, which also shows that the red pigment extracted is carotenoids.
Embodiment 5
Fermenting Methanotroph Methylomonas sp. ZR1 to Produce Carotenoids by Fermentation with Methane as Substrate
Single colony of the methanotroph Methylomonas sp. ZR1 formed on the plate is picked, inoculated into 30 ml of NMS liquid culture medium (using methane as carbon source) to culture at 30° C. and at 180 rpm; after being cultured for 2 days, OD 600 of the NMS liquid culture medium reaches 0.7, and inoculated into fresh NMS culture medium with 5% inoculation, fermenting in column reactor at 28° C., and after being cultured for 5 days, fermentation broth of single colony of methanotroph Methylomonas sp. ZR1 appears to be orange viscous liquid; the methanotroph Methylomonas sp. ZR1 is collected by centrifuging for 10 mins at 8000 rpm; the methanotroph Methylomonas sp. ZR1 collected is washed twice with distilled water, vacuum freeze-dried, then dried powder of the methanotroph Methylomonas sp. ZR1 is obtained; the dried powder of the methanotroph Methylomonas sp. ZR1 is weighed, extracted 3 times with methanol solution whose volume is 10 times of dried powder of the methanotroph Methylomonas sp. ZR1, then orange extraction solution of pigment is obtained; the orange extraction solution of pigment is filtered, and is dried by the rotary evaporation apparatus, then red pigment is obtained.
The Color Reaction of the Red Pigment in Concentrated Sulfuric Acid
The extracted red pigment is re-dissolved in 1 ml of dichloromethane, then pigment solution is obtained; 50 μl of the pigment solution was taken, diluted with chloroform to 0.5 ml, and being added with a few drops of concentrated sulfuric acid, then the pigment solution turns from red to blue-green, which shows that the red pigment extracted is carotenoids.
Full wave scanning of the red pigment is taken, 300 μl of the pigment solution is taken, and is added into quartz 96-well plate; while 300 μl of dichloromethane solution is kept as control, the pigment solution is scanned from 220 nm to 700 nm, the scan results are shown in FIG. 4 ,
The scan results show a three-finger peak which is a typical characteristic peak of carotenoid appears at around 500 nm, which also shows that the red pigment extracted is carotenoids.
Embodiment 6
Fermenting Methanotroph Methylomonas sp. ZR1 to Produce Carotenoids with Methane as Substrate
Single colony of the methanotroph Methylomonas sp. ZR1 formed on the plate is picked, inoculated into 30 ml of NMS liquid culture medium (using methane as carbon source) to culture at 28° C. and at 180 rpm, after being cultured for 2 days, OD 600 of the NMS liquid culture medium reaches 0.7, and inoculated into fresh NMS culture medium with 5% inoculation, fermenting in column reactor is conducted at 28° C., and after being cultured for 10 days, fermentation broth of single colony of methanotroph Methylomonas sp. ZR1 appears to be orange viscous liquid; the methanotroph is collected by centrifuging for 10 mins at 8000 rpm; the methanotroph collected is washed twice with distilled water, vacuum freeze-dried. then is dried powder of the methanotroph is obtained; dried powder of the methanotroph is weighed, extracted 3 times with methanol solution whose volume is 10 times the volume of dried powder of the methanotroph, then orange extraction solution of pigment is obtained; the orange extraction solution of pigment is filtered, and is dried by the rotary evaporation apparatus, then red pigment is obtained.
The Color Reaction of the Red Pigment in Concentrated Sulfuric Acid
The extracted red pigment is re-dissolved in 1 ml of dichloromethane, then pigment solution is obtained; 50 μl of the pigment solution was taken, diluted with chloroform to 0.5 ml, and being added with a few drops of concentrated sulfuric acid, then the solution turns from red to blue-green, which shows that the red pigment extracted is carotenoids.
Full wave scanning of the red pigment is taken, 300 μl of the pigment solution is taken, and added to a quartz 96-well plate, while 300 μl of dichloromethane solution is kept as control, the pigment solution is scanned from 220 nm to 700 nm, the scan results are shown in FIG. 5 .
The scan results show a three-finger peak which is a typical characteristic peak of carotenoid appears at around 500 nm, which also shows that the red pigment extracted is carotenoids.
Embodiment 7
Fermenting Methanotroph Methylomonas sp. ZR1 to Produce Polysaccharide with Methane as Substrate
Single colony of the methanotroph Methylomonas sp. ZR1 formed on the plate is picked, inoculated into 30 ml of NMS liquid culture medium (using methane as carbon source) to culture at 20° C. and at 180 rpm, after being cultured for 2 days, OD 600 of the NMS liquid culture medium reaches 0.7, and inoculated into fresh NMS culture medium with 5% inoculation, fermenting in column reactor at 20° C., and after being cultured for 3 days, fermentation broth of single colony of methanotroph Methylomonas sp. ZR1 appears to be orange viscous liquid; supernatant of the orange viscous liquid is collected by centrifuging for 10 mins at 8000 rpm; volume of the supernatant collected is condensed 10 times through using a rotary evaporator; the supernatant condensed is added with 95% ethanol to make the concentration of ethanol reach 70%, then the supernatant is remained at 4° C. overnight; after being centrifuged for 10 mins at 5000 rpm, supernatant is collected and is washed by ethanol, acetone and petroleum ether in turn, and being dried at 50° C. in an oven, then EPS raw material (polysaccharide) is obtained. The EPS raw material is re-dissolved in distilled water, and then is added into a dialysis bag whose cutoff molecular weight is 3.5 KDa. After being dialyzed for 3 days, and being desalted, polysaccharide solution desalted is obtained. The polysaccharide solution desalted is added with a Sevage solution of the same volume (the volume ratio of chloroform to n-butanol is 4 to 1), and swinging violently for 5 mins, centrifugating for 10 mins at 8000 rpm, collecting the upper polysaccharide solution, then removing protein 6˜8 times repeatedly. The deproteinized polysaccharide solution is concentrated under reduced pressure, freeze-dried, then dry polysaccharide samples are obtained.
Qualitative Reaction of Polysaccharide Solution
The Free Polysaccharide Analysis of Polysaccharide Solution
5 mg of dry polysaccharide samples are dissolved in 1 ml of distilled water, then polysaccharide solution is obtained; reducing sugars in the polysaccharide solution are determined by using 3,5-dinitrosalicylic acid, then measurement results show that the polysaccharide solution extracted do not contain free reducing polysaccharides.
MoLish Reaction
5 mg of dry polysaccharide samples are dissolved in 1 ml of distilled water, then polysaccharide solution is obtained; 200 μL of the polysaccharide solution is added into a clean glass test tube, and 100 μl of 6% phenol is added into the clean glass test tube, and 1 ml of concentrated sulfuric acid is added into the clean glass test tube, then color reacting solution of the dry polysaccharide samples is obtained; water is used as a negative control, and glucose is used as a positive control; the solution of the dry polysaccharide samples and the solution of the glucose all show yellow, color of the water do not change.
HPLC Analysis of Hydrolysate of Polysaccharide
5 mg of dry polysaccharide samples are dissolved in 1 ml of TFA aqueous solution whose concentration is 4 M; after being hydrolyzed for 8 h at 115° C., hydrolysate of polysaccharide is obtained; HPLC analysis of the hydrolysate of polysaccharide is taken; the HPLC analysis is taken by using BioRad42A column, with ultrapure water as mobile phase, at a flow rate of 0.6 ml/min and at 55° C.; the HPLC analysis is taken by Refractive Index Detector, then HPLC analysis results are shown in FIG. 6 .
The HPLC analysis results show that one peak of the hydrolysate of polysaccharide appears at 6.2 min, which is consistent with the time that peak of glucosamine standard sample appears, and another peak of the hydrolysate of polysaccharide appears at 16.2 min, which is consistent with the time that peak of glucose standard sample appears, and another peak of the hydrolysate of polysaccharide appears at 17.8 min, which is consistent with the time that peak of mannose standard sample appears. The HPLC analysis results show the polysaccharides which are produced by the methanotroph Methylomonas sp. ZR1 are mainly heteropolysaccharide which is consisted of glucosamine, glucose and mannose.
Embodiment 8
Fermenting Methanotroph Methylomonas sp. ZR1 to Produce Polysaccharide with Methane as Substrate
Single colony of the methanotroph Methylomonas sp. ZR1 formed on the plate is picked, inoculated into 30 ml of NMS liquid culture medium (using methane as carbon source). to culture at 25° C. and at 180 rpm; after being cultured for 2 days, OD 600 of the NMS liquid culture medium reaches 0.7, and inoculated into fresh NMS culture medium with 5% inoculation; fermenting in column reactor at 28° C., and after being cultured for 6 days, fermentation broth of single colony of methanotroph Methylomonas sp. ZR1 appears to be orange viscous liquid; supernatant of the orange viscous liquid is collected by centrifuging for 10 mins at 8000 rpm; volume of the supernatant collected is condensed 10 times through using a rotary evaporator; the supernatant condensed is added with 95% ethanol to make the concentration of ethanol reach 70%, then the supernatant is remained at 4° C. overnight; after being centrifuged for 10 mins at 5000 rpm, supernatant is collected, and is washed by ethanol, acetone and petroleum ether in turn, and being dried at 50° C. in an oven, then EPS raw material (polysaccharide) is obtained. The EPS raw material is re-dissolved in distilled water, and then is added into a dialysis bag whose cutoff molecular weight is 3.5 KDa, and after being dialyzed for 3 days, and being desalted, then polysaccharide solution desalted is obtained. The polysaccharide solution desalted is added with a Sevage solution of the same volume (the volume ratio of chloroform to n-butanol is 4 to 1), and swinging violently for 5 mins, centrifugating for 5 mins at 8000 rpm, collecting the upper polysaccharide solution, then removing protein 6˜8 times repeatedly. The polysaccharide solution removed protein is concentrated under reduced pressure, freeze-dried, then dry polysaccharide samples are obtained.
Qualitative Reaction of Polysaccharide Solution
The Free Polysaccharide Analysis of Polysaccharide Solution
5 mg of dry polysaccharide samples are dissolved in 1 ml of distilled water, then polysaccharide solution is obtained; reducing sugars in the polysaccharide solution are determined by using 3,5-dinitrosalicylic acid, then the measurement results show that the polysaccharide solution extracted do not contain free reducing polysaccharides.
MoLish Reaction
5 mg of dry polysaccharide samples is dissolved in 1 ml of distilled water, then polysaccharide solution is obtained; 200 μL of the polysaccharide solution is added into a clean glass test tube, then 100 μl of 6% phenol is added into the clean glass test tube, and 1 ml of concentrated sulfuric acid is added into the clean glass test tube, then color reacting solution of the dry polysaccharide samples is obtained; water is used as a negative control, and glucose is used as a positive control; the solution of the dry polysaccharide samples and the solution of the glucose all show yellow, color of the water do not change.
HPLC Analysis of Hydrolysate of Polysaccharide
5 mg of dry polysaccharide samples are dissolved in 1 ml of TFA aqueous solution whose concentration is 4 M; after being hydrolyzed for 8 h at 115° C., hydrolysate of polysaccharide is obtained; HPLC analysis of the hydrolysate of polysaccharide is taken; the HPLC analysis is taken by using BioRad42A column, with ultrapure water as mobile phase, at a flow rate of 0.6 ml/min and at 55° C.; the HPLC analysis is taken by Refractive Index Detector then HPLC analysis results are shown in FIG. 7 .
The HPLC analysis results show one peak of the hydrolysate of polysaccharide appears at 6.2 min, which is consistent with the time that peak of glucosamine standard sample appears, and another peak of the hydrolysate of polysaccharide appears at 16.2 min, which is consistent with the time that peak of glucose standard sample appears, and another peak of the hydrolysate of polysaccharide appears at 17.8 min, which is consistent with the time that peak of mannose standard sample appears. The HPLC analysis results show the polysaccharides which are produced by the methanotroph Methylomonas sp. ZR1 are mainly heteropolysaccharide, which includes glucosamine glucose and mannose.
Embodiment 9
Fermenting Methanotroph Methylomonas sp. ZR1 to Produce Polysaccharide with Methane as Substrate
Single colony of the methanotroph Methylomonas sp. ZR1 formed on the plate is picked, inoculated into 30 ml of NMS liquid culture medium (using methane as carbon source) to culture at 28° C. and at 180 rpm, after being cultured for 2 days, OD 600 of the NMS liquid culture medium reached 0.7, and inoculated into fresh NMS culture medium with 5% inoculation, fermenting in column reactor at 28° C., and after being cultured for 10 days, fermentation broth of single colony of methanotroph Methylomonas sp. ZR1 appears to be orange viscous liquid; supernatant of the orange viscous liquid is collected by centrifuging for 10 mins at 8000 rpm; volume of the supernatant collected is condensed 10 times through using a rotary evaporator; the supernatant condensed is added with 95% ethanol to make the concentration of ethanol reach 70%, then the supernatant is remained at 4° C. overnight; after being centrifuged for about 10 mins at 5000 rpm, supernatant is collected, and is washed by ethanol, acetone and petroleum ether in turn, and being dried at 50° C. in an oven, then EPS raw material (polysaccharide) is obtained. The EPS raw material is re-dissolved in distilled water, and then is added into a dialysis bag whose cutoff molecular weight is 3.5 KDa. After being dialyzed for 3 days, and being desalted, then polysaccharide solution desalted is obtained. The polysaccharide solution desalted is added with a Sevage solution of the same volume (the volume ratio of chloroform to n-butanol is 4 to 1), and swinging violently for 5 mins, centrifugating for 10 mins at 8000 rpm, collecting the upper polysaccharide solution, then removing protein 6˜8 times repeatedly. The deproteinized polysaccharide solution is concentrated under reduced pressure, freeze-dried, then dry polysaccharide samples are obtained.
Qualitative Reaction of Polysaccharide Solution
The Free Polysaccharide Analysis of Polysaccharide Solution
5 mg of dry polysaccharide samples are dissolved in 1 ml of distilled water, then polysaccharide solution is obtained; reducing sugars in the polysaccharide solution are determined by using 3,5-dinitrosalicylic acid, then measurement results show that the polysaccharide solution extracted does not contain free of reducing polysaccharides.
MoLish Reaction
5 mg of dry polysaccharide samples is dissolved in 1 ml of distilled water, then polysaccharide solution is obtained; 200 μL of the polysaccharide solution is added to a clean glass test tube, and 100 μl of 6% phenol is added into the clean glass test tube, and 1 ml of concentrated sulfuric acid is added into the clean glass test tube, then color reacting solution of the dry polysaccharide samples is obtained; water is used as a negative control, and glucose is used as a positive control; the solution of the dry polysaccharide samples and the solution of the glucose all show yellow, color of the water do not change.
HPLC Analysis of Hydrolysate of Polysaccharide
5 mg of dry polysaccharide samples dissolved in 1 ml of TFA aqueous solution whose concentration is 4 M, after being hydrolyzed for 8 h at 115° C., hydrolysate of polysaccharide is obtained; HPLC analysis of the hydrolysate of polysaccharide is taken. the HPLC analysis is taken by using BioRad42A column, with ultrapure water as mobile phase, at a flow rate of 0.6 ml/min, at 55° C.; the HPLC analysis is taken by Refractive Index Detector, then HPLC analysis results are shown in FIG. 8 .
The HPLC analysis results show that one peak of the hydrolysate of polysaccharide appears at 6.2 min, which is consistent with the time that peak of glucosamine standard sample appears, and another peak of the hydrolysate of polysaccharide appears at 16.2 min, which is consistent with the time peak of glucose standard sample appears, and another peak of the hydrolysate of polysaccharide appears at 17.8 min, which is consistent with the time peak of mannose standard sample appears. The HPLC analysis results show the polysaccharides which are produced by the methanotroph Methylomonas sp. ZR1 are mainly heteropolysaccharide, which includes glucosamine, glucose and mannose.
Although the embodiments of the present invention have been disclosed above, but it is not limited to the use of the specification and embodiments listed. It can be applied to various fields suitable for the present invention. Those skilled in the art can easily modify. Therefore, without departing from the general concept of the scope defined by the claims and the equivalents, the present invention is not limited to the specific details and illustrations herein illustrated and described herein.
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The present invention discloses a high concentration methanol tolerant methanotroph and its application, a accession number of the methanotroph in China General Microbiological Culture Collection Center being CGMCC No. 9873, deposit date being Oct. 29, 2014, category names being Methylomonas sp. ZR1. The methanotroph Methylomonas sp. ZR1 disclosed by the present invention can grow rapidly by using methane, and can tolerate with high concentration of methanol. The methanotroph Methylomonas sp. ZR1 can use C 1 compounds such as methane and methanol to produce high value-added products such as carotenoids and polysaccharides, which has high application prospect in biological transformation of one-carbon chemistry.
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This application is related to U.S. application Ser. No. 60/080,856, the specification of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
This invention relates to hoses used to vent appliances, and in particular to a connector for connecting a clothes dryer discharge hose to an exhaust vent hose or fixture.
Clothes dryers, and other appliances, often include a discharge hose to exhaust a discharge air stream from the appliance. Dryer hoses are somewhat troublesome to connect and disconnect form a discharge as required to install, remove or service the appliance. The typical dryer installation puts the hose behind the dryer, and many times the dryer must be moved in order to disconnect, inspect, clean, or replace the dryer hose. Further difficulty lies in the manner in which the exhaust hose is connected to the discharge vent (normally one or more large hose clamps), and in the tendency of the thin, flexible walls of the relatively large diameter hoses to bend out of shape. A need therefore remains for an improved dryer hose discharge connection which addresses the shortcomings of the prior art.
SUMMARY OF THE INVENTION
The present invention provides a reliable, simple and quick coupler for connecting dryer hoses to exhaust vents for any installation. The invention simplifies inspection and cleaning of dryer hoses to minimize the potential fire hazard from lint buildup in a dryer hose, and provides a more secure hose to exhaust vent connection to prevent disconnection of the hose from the vent.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the discharge hose portion of one embodiment of the invention.
FIG. 2 is a side elevational view of the discharge hose portion shown in FIG. 1.
FIG. 3 is a top plan view of the discharge hose portion shown in FIG. 1.
FIG. 4 is a perspective view of the exhaust vent portion of one embodiment of the invention.
FIG. 5 is a side elevational view of the discharge hose portion shown in FIG. 4.
FIG. 6 is a top plan view of the discharge hose portion shown in FIG. 4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning now to FIGS. 1-6, a dryer hose connector according to a preferred embodiment of the invention includes a first member 10 (FIG. 1) and a second member 30 (FIG. 4). Each of members 10 and 30 includes a cylindrical portion 12 and 32 respectively, and flanges 13 and 33 respectively. In one embodiment, portions 12 and 32 are sized to be received into a flexible dryer hose (not shown). Reinforcing ribs 14 are provided for added strength, and to permit attaching the connector to the hose without the need for clamps. First member 10 is preferably attached by cylindrical portion 12 to the discharge hose of a dryer or other appliance. Second member 30 is preferably attached to a hose connected to a discharge vent from the room in which the appliance is located. Second member 30 may be mounted to the wall, floor, or ceiling with three screw fasteners inserted through holes 36a-c spaced at 120 degree intervals around the flange 33. Member 10 includes an annular sealing surface 19 which in the preferred embodiment protrudes slightly from flange 13. Member 30 includes a corresponding sealing surface 39 which engages sealing surface 13 to provide a substantially gas-tight seal between members 10 and 30.
Flange 13 includes three openings 18a-c which, in the preferred embodiment, are spaced evenly around the flange. Flange 33 includes three protruding lugs 38a-c which are spaced about flange 33, and which are positioned to engage each of openings 18a-c respectively. Member 10 interconnects with member 30 by being rotated which moves a portion of the flange adjacent each of openings 18a-c beneath a respective resilient lug 38, which holds flange 13 in place. Members 10 and 30 are disengaged in reverse order; flanges members 10 and 30 are rotated in the opposite direction until lugs 38a-c can be removed from openings 18a-c. Those of skill in the art will appreciate that the shape of openings 18 and lugs 38, and other details of the invention, could be varied from those shown without departing from the spirit and scope of the following claims. In the preferred embodiment, members 10 and 30 are formed of a molded polymeric material, although any material or method of forming is considered within the scope of the invention.
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A hose connector having a pair of flanged cylindrical members which can be readily connected and disconnected by insertion of one or more protruding lugs on one flange into corresponding openings in the other flange.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This patent application claims the benefit of U.S. Provisional Patent Application Nos. 61/467,858, filed Mar. 25, 2011, and 61/490,138, filed May 26, 2011, which are incorporated by reference in their entireties herein. This patent application is also a continuation of co-pending U.S. patent application Ser. No. 13/428,625, filed Mar. 23, 2012, which is incorporated by reference in its entirety herein.
BACKGROUND
[0002] Sinks have drains for permitting water to drain from the sink into a plumbing system. During installation, drains are typically inserted into the interior of the sink basin and dropped into an opening at the base of the basin. The drain has a rim with a diameter exceeding the diameter of the opening such that the rim rests on the top surface of the base of the sink basin. Often, the portion of the base surrounding the opening has a countersink portion such that the rim of the drain is generally flush with the adjacent portion of the base of the sink. Nonetheless, a groove is present between the rim of the drain and the sink base that is difficult to clean and susceptible to bacterial growth. In addition, the presence of the groove is visible to a user and aesthetically unappealing.
BRIEF SUMMARY
[0003] Embodiments of sinks and drains for sinks are disclosed herein. The embodiments permit the attachment of a drain to a sink such that the drain is substantially disposed below the top surface of the sink basin, and such that there is no discernable separation between the base of the sink basin and the drain when viewed from above the sink. A method of making a sink is also disclosed wherein there is no discernable separation between the base of the sink basin and the drain when viewed from above the sink.
[0004] A sink is described comprising a sink basin, a drain entry portion, a flange plate, a strainer, a first seal, and a second seal. The sink basin can have a sidewall and a base. The base can have an opening. The drain entry portion can be disposed at the opening and attached to the base. The drain entry portion can extend away from the base. The drain entry portion can have a lip for receiving the first seal. The flange plate can have an inner edge portion and an outer edge portion. The outer edge portion can be in contact with the first seal. The first seal can be disposed between the lip and the outer edge portion. The strainer can be disposed near the inner edge portion. The second seal can be disposed between the strainer and the inner edge portion.
[0005] A drain is also disclosed comprising a first seal, a drain entry portion, a flange plate, a strainer, and a second seal. The drain entry portion can have a lip for receiving the first seal. The flange plate can have an inner edge portion and an outer edge portion. The outer edge portion can be in contact with the first seal. The first seal can be disposed between the lip and the outer edge portion. The strainer can be disposed near the inner edge portion. The second seal can be disposed between the strainer and the inner edge portion.
[0006] A method of making a sink is also described. The method comprises forming a sink basin having a sidewall and a base, providing a drain entry portion, welding the drain entry portion to the base at the opening, and grinding the weld at the opening such that the drain entry portion appears integrally formed with the base when viewing into the sink basin. The base can have an opening. The drain entry portion can be cylindrical.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a perspective view of a sink;
[0008] FIG. 2 is a sectional view of a drain for the sink of FIG. 1 ;
[0009] FIG. 3 is a sectional view of a second embodiment of a drain for the sink of FIG. 1 ;
[0010] FIG. 4 is a sectional view of a third embodiment of a drain for the sink of FIG. 1 ;
[0011] FIG. 5 is a perspective view of another embodiment of a sink;
[0012] FIG. 6 is a sectional view of an embodiment of a drain for the sink of FIG. 5 ;
[0013] FIG. 7 is a sectional view of an embodiment of a drain for a sink attached to a garbage disposer;
[0014] FIG. 8 is a fragmentary bottom perspective view showing the drain of FIG. 7 ;
[0015] FIG. 9 is a sectional view of a drain entry portion welded to a sink;
[0016] FIG. 10 is a sectional view of another embodiment of a drain entry portion welded to a sink; and
[0017] FIG. 11 is a sectional view of a further embodiment of a drain entry portion welded to a sink.
DETAILED DESCRIPTION
[0018] Referring to FIG. 1 , a sink 100 with the appearance of an edgeless drain is shown. The sink 100 can include one or more sink basins 102 and a rim 104 . The sink basin 102 can include one or more sidewalls 106 and a base 108 . The base 108 can include an opening 110 for a drain. The sidewalls 106 and base 108 can form an interior surface of the basin 102 to retain water and washable items. The rim 104 can be used to support the basin 102 in an above-mount arrangement or under-mount arrangement with respect to a counter. The sink 100 can be made of any suitable material, such as stainless steel.
[0019] Referring to FIG. 2 , a drain 101 is shown that can include a drain entry portion 112 , a flange plate 114 , a strainer 116 , a drain pipe 118 , and a cover 120 . The drain entry portion 112 can be cylindrical and can extend from the bottom of the sink basin at the opening for the drain 101 . The drain entry portion 112 can include a first end portion 122 and a second end portion 124 . In some embodiments, the drain entry portion 112 can be formed as part of the sink 100 . In other embodiments, the drain entry portion 112 can be a component separately manufactured from the sink 100 . The first end portion 122 of the drain entry portion 112 can be welded to the base of the sink to fix the drain entry portion 112 to the sink basin at the opening. In order to conceal the welded intersection between the drain entry portion 112 and the base, a grinding and polishing operation can be applied such that the intersection is hidden to a user looking into the sink basin. In addition, because the drain entry portion 112 can be mounted from below without the need for a drain rim to rest on the base, there is no groove between the drain 101 and the sink basin 102 . From a user's perspective, the drain opening leads directly into the drain 101 . The weld between the sink basin and the drain entry portion 112 can be accomplished in any suitable manner, such as with a shielding gas weld.
[0020] FIGS. 9-11 show examples of suitable embodiments of a drain entry portion welded to a base of a sink. It will be appreciated, however, that the drain entry portion can be coupled to the sink via any suitable manner.
[0021] Referring to FIG. 9 , the drain entry portion 612 can include a radially extending flange 680 . The flange 680 can be disposed against the underside of the sink base 108 . The drain entry portion 612 can have an interior diameter that is smaller than the opening 110 of the sink 100 such that there is a portion of the flange 680 extending inward from the opening 110 that can receive a solder material 682 for welding the drain entry portion 612 to the sink 100 . As discussed, after welding, a grinding and polishing operation can be applied to the weld such that the intersection between the drain entry portion 612 and the sink 100 is hidden to a user looking into the sink basin 102 .
[0022] Turning to FIG. 10 , the drain entry portion 712 can include a radially extending flange 780 . The flange 780 can be disposed within the opening 110 such that the flange abuts the portion of the sink base 108 forming the opening 110 . Thus, the perimeter of the flange 780 has a diameter that is smaller than the opening 110 of the sink 100 such that the flange 780 fits within the opening 110 . The thickness of the flange 780 can be smaller than the thickness of the sink base 108 such that a space is formed on the upper surface of the flange 780 for receiving a solder material 782 for welding the drain entry portion 712 to the sink 100 . As discussed, after welding, a grinding and polishing operation can be applied to the weld such that the intersection between the drain entry portion 612 and the sink 100 is hidden to a user looking into the sink basin 102 .
[0023] As shown in FIG. 11 , the drain entry portion 812 can include a radially extending flange 880 . The flange 880 can be disposed away from the edge 884 of the drain entry portion 812 on the first end portion 822 . The flange 880 can be disposed against the underside of the sink base 108 , and the edge 884 of the drain entry portion 812 can have an exterior diameter that is smaller than the opening 110 of the sink 100 . The flange 880 can be located on the drain entry portion 812 a sufficient distance from the edge such that the edge is disposed below the upper surface of the sink base 102 and such that the edge 884 can receive a solder material 882 for welding the drain entry portion 812 to the sink 100 . As discussed, after welding, a grinding and polishing operation can be applied to the weld such that the intersection between the drain entry portion 812 and the sink 100 is hidden to a user looking into the sink basin 102 .
[0024] Referring again to FIG. 2 , the second end portion 124 of the drain entry portion 112 can include a lip 126 for receiving a seal 128 . The flange plate 114 can have an outer edge portion 130 and an inner edge portion 132 . The outer edge portion 130 of the flange plate 114 can rest on the seal 128 such that the seal 128 prevents water inside the drain 101 from passing between the intersection of the drain entry portion 112 and the flange plate 114 . The inner edge portion 132 of the flange plate 114 can receive a lip 134 of the drain pipe 118 for supporting the drain pipe 118 .
[0025] The strainer 116 can be disposed above the lip 134 of the drain pipe 118 and the inner edge portion 132 of the flange plate 114 . The strainer 116 can include a seal 136 for contacting the lip 134 of the drain pipe 118 and preventing the passage of water in the drain 101 past the seal 136 . The strainer 116 can be press fit within the flange plate 114 . The strainer 116 can have one or more openings in the bottom of the strainer to permit water to flow past the strainer 116 and into the drain pipe 118 .
[0026] The drain 101 can include a cover 120 over the drain entry portion 112 , the flange plate 114 , and the strainer 116 . The cover 120 can be secured to the sink with a locking nut 138 . The drain pipe 118 can be threaded to receive the locking nut 138 , and the locking nut 138 can be tightened to enhance the seal force applied between the drain entry portion 112 and the flange plate 114 . A coupler 140 can be used to attach the drain pipe 118 to a pipe 142 leading to a trap.
[0027] A removeable strainer basket 144 can be disposed within the drain 101 . The strainer basket 144 can include a basket portion 146 for capturing solids and a stopper 148 that can be lowered into the strainer 114 to plug the drain 101 .
[0028] Turning to FIG. 3 , a second embodiment of a drain 201 is shown that can include a drain entry portion 212 , an attachment portion 250 , a strainer 216 , and a drain pipe 218 . The drain entry portion 212 can be cylindrical and can extend from the bottom of the sink basin at the opening for the drain 201 . The drain entry portion 212 can include a first end portion 222 and a threaded exterior surface 252 . The drain entry portion 212 can be a component separately manufactured from the sink. The first end portion 222 of the drain entry portion 212 can be welded to the base to fix the drain entry portion 212 to the sink basin at the opening. In order to conceal the welded intersection between the drain entry portion 212 and the base, a grinding and polishing operation can be applied such that the intersection is hidden to a user looking into the sink basin. In addition, because the drain entry portion 212 can be mounted from below without the need for a drain rim to rest on the base, there is no groove between the drain 201 and the sink basin. From a user's perspective, the drain opening leads directly into the drain 201 . The weld between the sink basin and the drain entry portion 212 can be accomplished in any suitable manner, such as with a shielding gas weld.
[0029] The attachment portion 250 can have a threaded surface 254 and an inner edge portion 232 . The attachment portion threaded surface 254 can be received and tightened to the threaded surface 252 of the drain entry portion 212 . The inner edge portion 232 of the attachment portion 250 can receive a lip 234 of the drain pipe 218 for supporting the drain pipe 218 .
[0030] The strainer 216 can be disposed above the lip 234 of the drain pipe 218 and the inner edge portion 232 of the attachment portion 250 . The strainer 216 can include a seal 236 for contacting the lip 234 of the drain pipe 218 and preventing the passage of water in the drain 201 past the seal 236 . The strainer 216 can be press fit within the attachment portion 250 . The strainer 216 can have one or more openings in the bottom of the strainer to permit water to flow past the strainer 216 and into the drain pipe 218 . The drain pipe 218 can be threaded to receive a coupler that can be used to attach the drain pipe to a pipe leading to a trap.
[0031] A removeable strainer basket 244 can be disposed within the drain 201 . The strainer basket 244 can include a basket portion 246 for capturing solids and a stopper 248 that can be lowered into the strainer 216 to plug the drain 201 .
[0032] Referring to FIG. 4 , a third embodiment of a drain 301 is shown that can include a drain entry portion 312 , an attachment portion 350 , a strainer 316 , and a drain pipe 318 . The drain entry portion 312 can be cylindrical and can extend from the bottom of the sink basin at the opening for the drain 301 . In this embodiment, the drain entry portion 312 can be formed from the sink basin during the drawing process to shape the sink. Thus, the drain entry portion 312 can be integrally formed to lead directly from the sink basin to the drain 301 . Threads 352 can be welded or otherwise attached to the drain entry portion 312 .
[0033] The attachment portion 350 can have a threaded surface 354 and an inner edge portion 332 . The attachment portion threaded surface 354 can be received and tightened to the threads 352 of the drain entry portion 312 . The inner edge portion 332 of the attachment portion 350 can receive a lip 334 of the drain pipe 318 for supporting the drain pipe 318 .
[0034] The strainer 316 can be disposed above the lip 334 of the drain pipe 318 and the inner edge portion 332 of the attachment portion 350 . The strainer 316 can include a seal 336 for contacting the lip 334 of the drain pipe 318 and preventing the passage of water in the drain 301 past the seal. The strainer 316 can be press fit within the attachment portion 350 . The strainer 316 can have one or more openings in the bottom of the strainer to permit water to flow past the strainer 316 and into the drain pipe 318 . The drain pipe 318 can be threaded to receive a coupler that can be used to attach the drain pipe to a pipe leading to a trap.
[0035] A removeable strainer basket 344 can be disposed within the drain 301 . The strainer basket 301 can include a basket portion 346 for capturing solids and a stopper 348 that can be lowered into the strainer 316 to plug the drain 301 .
[0036] FIGS. 5 and 6 show another embodiment of an edgeless drain 401 suitable for use with a non-metallic sink 400 , such as a sink made of granite or other suitable stone. The drain 401 can include a first drain entry portion 411 , a second drain entry portion 412 , a flange plate 414 , a strainer 416 , a drain pipe 418 , and a cover 420 . The first drain entry portion 411 can be cylindrical and can extend from the bottom of the sink basin at the opening for the drain 401 . Similar to the embodiment of FIG. 4 , the first drain entry portion 411 can be formed as part of the sink basin during the process of making the sink. Thus, the first drain entry portion 411 leads directly from the sink basin into the drain 401 .
[0037] The second drain entry portion 412 can include a first end portion 422 and a second end portion 424 . The second drain entry portion 412 can be a component separately manufactured from the sink. The first end portion 422 of the second drain entry portion 412 can include one or more apertures such that the drain entry portion 412 can be fastened to the bottom of the sink using suitable fasteners 456 disposed through the apertures, such as one or more screws.
[0038] The second end portion 424 of the second drain entry portion 412 can include a lip 426 for receiving a seal 428 . The flange plate 414 can have an outer edge portion 430 and an inner edge portion 432 . The outer edge portion 430 of the flange plate 414 can rest on the seal 428 such that the seal 428 prevents water inside the drain 401 from passing between the intersection of the second drain entry portion 412 and the flange plate 414 . The inner edge portion 432 of the flange plate 414 can receive a lip 434 of the drain pipe 418 for supporting the drain pipe 418 .
[0039] The strainer 416 can be disposed above the lip 434 of the drain pipe 418 and the inner edge portion 432 of the flange plate 414 . The strainer 416 can include a seal 436 for contacting the lip 434 of the drain pipe 418 and preventing the passage of water in the drain 401 past the seal 436 . The strainer 416 can be press fit within the flange plate 414 . The strainer 416 can have one or more openings in the bottom of the strainer to permit water to flow past the strainer 416 and into the drain pipe 418 .
[0040] The drain 401 can include a cover 420 over the second drain entry portion 412 , the flange plate 414 , and the strainer 416 . The cover 420 can be secured to the sink with a locking nut 438 . The drain pipe 418 can be threaded to receive the locking nut 438 , and the locking nut 438 can be tightened to enhance the seal force applied between the second drain entry portion 412 and the flange plate 414 . A coupler 440 can be used to attach the drain pipe 418 to a pipe 442 leading to a trap.
[0041] A removeable strainer basket 444 can be disposed within the drain 401 . The strainer basket 444 can include a basket portion 446 for capturing solids and a stopper 448 that can be lowered into the strainer 416 to plug the drain 401 .
[0042] It will be appreciated that the above-described sink and drain embodiments may be utilized with a garbage disposer. For example, FIGS. 7 and 8 show an embodiment of a drain 501 attached to a garbage disposer 560 . In this embodiment, the drain 501 can include a drain entry portion 512 , a disposer attachment ring 562 , a strainer 516 , and a disposer assembly 564 . The drain entry portion 512 can be cylindrical and can extend from the bottom of the sink basin at the opening for the drain 501 . The drain entry portion 512 can include a first end portion 522 and a threaded exterior surface 552 . The drain entry portion 512 can be a component separately manufactured from the sink. The first end portion 522 of the drain entry portion 512 can be welded to the base to fix the drain entry portion 512 to the sink basin at the opening. In order to conceal the welded intersection between the drain entry portion 512 and the base, a grinding and polishing operation can be applied such that the intersection is hidden to a user looking into the sink basin. In addition, because the drain entry portion 512 can be mounted from below without the need for a drain rim to rest on the base, there is no groove between the drain 501 and the sink basin. From a user's perspective, the drain opening leads directly into the drain 501 . The weld between the sink basin and the drain entry portion 512 can be accomplished in any suitable manner, such as with a shielding gas weld.
[0043] The disposer attachment ring 562 can have a threaded surface 566 and a lower portion 568 . The flange plate threaded surface 552 can be received and tightened to the threaded exterior surface 566 of the drain entry portion 512 . The lower portion 568 can have a detent 570 for receiving a snap ring 572 . The strainer 516 can be disposed above detent 570 . The strainer 516 can have one or more openings in the bottom of the strainer to permit water to flow past the strainer 516 and into the disposer 560 .
[0044] The disposer assembly 564 can include a backup flange 574 and a mounting ring 576 . The backup flange 574 can be generally triangular and the mounting ring 576 can have a plurality of tightening screws 578 for contacting the backup flange 574 near each vertex of the backup flange 574 . During tightening of the screws 578 , the mounting ring 576 can be retained to the disposer attachment ring 562 by the snap ring 572 . As is known to those of skill in the art, the disposer 560 can include a bracket for hanging the disposer from the mounting ring.
[0045] A removeable strainer basket 544 can be disposed within the drain 501 . The strainer basket 544 can include a basket portion 546 for capturing solids and a stopper 548 that can be lowered into the strainer 516 to plug the drain 501 .
[0046] All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.
[0047] The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.
[0048] Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.
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Sinks and drains for sinks permitting the attachment of the drain to the sink such that the drain is substantially disposed below the top surface of the sink basin, and such that there is no discernable separation between the base of the sink basin and the drain when viewed from above the sink. A method of making a sink such that there is no discernable separation between the base of the sink basin and the drain when viewed from above the sink.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to improved signal determination in nuclear magnetic resonance well logging. More specifically, the invention is a method directed towards eliminating spurious effects of magneto-acoustic ringing from obtained resonance signals.
2. Description of the Related Art
Nuclear magnetic resonance (NMR instruments have been adapted for use in wellbores drilled through earth formations. Generally speaking, NMR instruments used for analyzing earth formations include a magnet for inducing a static magnetic field in the earth formations to be evaluated, an antenna placed proximate to the formations to be analyzed, and circuitry adapted to conduct radio-frequency (RF) power pulses through the antenna to induce an RF magnetic fields in the same formations. The circuitry also includes a receiver adapted to detect signals induced in the antenna (or a separate receiving antenna). The induced signals are related to NMR phenomena induced in the formation of interest by the combined action of the static magnetic field and the RF magnetic field.
Typically, measurement of NMR related phenomena in the earth formation is performed by introducing a static magnetic field B 0 and allowing some time for the static magnetic field to polarize nuclear spins in the formation in a direction substantially along the direction of the static magnetic field. Bb may be produced by one or more permanent magnet or electromagnets. An oscillating magnetic field B 1 may be produced by one or more RF antennas to excite and detect nuclear magnetic resonance. A typical sequence of RF pulses is known as the Carr-Purcell-Meiboom-Gill (CPMG) sequence. The first RF pulse of this sequence is known as the excitation pulse has a magnitude and duration selected to reorient the nuclear magnetization by about 90 degrees from its previous orientation. After a selected time, successive RF pulses, known as refocusing pulses, are passed through the antenna. Each of these pulses typically has a magnitude and duration selected to reorient the nuclear spin axes by about 180 degrees from their immediately previous orientations. Each refocusing pulse enables the nuclear spin axes to “rephase” or realign with each other. After application of an RF pulse, the magnetization begins to precess around B 0 and produces a detectable signal in the antenna. The induced signals, known as “spin echoes”, are generally measured during the time interval between each successive refocusing pulse. The amplitude of the spin echo signals, and the rate at which the spin echo amplitudes change during a measurement sequence, are related to properties of interest of the earth formations, such as fractional volume of pore space (porosity) and the properties of fluids present in the pore spaces. The frequency of the RF magnetic field needed to reorient the nuclear magnetization, is equal to the Larmor frequency a ω 0 =γB 0 where γ is the gyromagnetic ratio. For evaluation of earth formations, the static magnetic field amplitude and RF magnetic field frequency are typically selected to excite NMR phenomena in hydrogen nuclei, although other nuclei may be used for NMR evaluation of earth formations.
Exciting the antenna with RF power pulses in the presence of a strong static magnetic field causes mechanical excitation of the antenna. Mechanical excitation of the antenna leads to excitation of a signal, called “ringing”, in the antenna. This phenomenon can be explained as follows: The RF magnetic field induces eddy currents within the skin depth of the metal. In the presence of a static magnetic field, the electrons experience a Lorentz force. This same force affects the lattice as well, causing the acoustic waves. As discussed in Buess et al. (see M. L. Buess and G. L. Petson. Rev. Sci. Instrum. 49(8), 1978.), the ionic displacement is proportional to the strength of the RF magnetic field at the surface of the metal. A reciprocal mechanism converts acoustic waves into oscillating RF magnetic fields, which thereby induces voltage in the NMR receiver coil.
Another source of the magneto-acoustic ringing is generation of ultrasonic waves in non-conductive magnetic materials via the process of magneto-striction. The non-conductive magnetic material, typically ferrite, can be used as a permanent magnet, as discuss in Taicher '713 (U.S. Pat. No. 4,710,713). Alternatively, the magnetic material can be used as the antenna core, as discussed in Taicher '979 (U.S. Pat. No. 4,698,979) and Kleinberg '787 (U.S. Pat. No. 5,055,787). In these uses also, the inverse effect causes the magnetization oscillations to induce voltage in the NMR receiver. The effect is also linearly proportional with respect to the RF magnetic: field at the surface of the magnetic material.
The ringing is unrelated to NMR phenomena, and frequently has a very large amplitude. The amplitude of the ringing is often highest right after application of each RF pulse, and is of such a magnitude as to make it difficult to measure the amplitude of induced NMR signals. Reducing the effect, of ringing on NMR measurement is very important in well logging applications, among others, because significant information about the properties of the earth formations are determined by the amplitudes of spin echoes occurring shortly after the RF pulses.
Several methods are known in the art for reducing ringing. One device for reducing ringing is to have the magnet arranged so as to dispose the antenna in a region having substantially zero static magnetic field amplitude. An NMR apparatus which has this arrangement is described, for example, in U.S. Pat. No. 5,712,566 issued to Taicher. Yet another device for reducing ringing is to provide separate antennas for inducing the RF magnetic field and detecting the NMR induced signals, where these two antennas are substantially orthogonal to each other. Ringing induced in the transmitting antenna is substantially undetected by the receiving antenna. See for example, the Taicher '566 patent referred to previously.
A standard technique for suppressing the magneto-acoustic ringing due to an applied CPMG sequence includes repeating the measurement with the RF phase of the excitation pulse inverted. Thus the NMR pulse sequence is implemented in the form of phase alternated pairs (PAPs):
where TW is the wait time, 90 ±x is the excitation pulse with RF carrier phase alternated, B y is the refocusing pulse, t cp =TE/2 is half of the echo spacing (TE). As a result of this alternation, the NMR signal inverts the phase of the echoes but leaves unaffected the ringing signal. As a preferred option of operation, the refocusing pulse B y is a 180° pulse. The ringing signal can be eliminated from a pair of phase alternated CPMG sequences by subtracting the echo signal generated by one CPMG sequence from the echo signal generated by another CPMG sequence within the alternated pair. The subtractions eliminates ringing caused by the refocusing pulses and also eliminates a DC offset of the receiver.
One shortcoming of the PAP approach is that it does not eliminate ringing due to the excitation pulse. Since the ringing signal due to the excitation pulse inverts its phase the same way as the echo signal, it can not be subtracted using the method of alternated pairs. As a result, this ringing typically corrupts the first one or two echoes in the CPMG sequence, thereby affecting the resolvability of the fast relaxation components in the NMR relaxation spectrum.
A method of eliminating the ringing due to the excitation pulse is described in U.S. Pat. No. 6,204,663, issued to Prammer. The method of Prammer '663 is based on changing the measurement frequency between certain pulse sequences and averaging out data points obtained from the different sequences in a way that effectuates cancellation of the spurious signals. Since mechanical resonance producing an acoustic ringing occurs at its own frequency, the ringing signal will change its phase with respect to the changed NMR signal. If the frequency change is made equal to one-half of the time between excitation pulse and acquisition, an additional phase difference of 180 degrees between ringing signals in two sequences can be achieved. Then, adding the signals from the two measurements eliminates ringing from the excitation pulse. A drawback of this approach is that the width of the acquisition window may be comparable with TE, so the ringing subtraction can not be achieved over the entire echo acquisition window. The method of Prammer '663 is difficult to implement if there is a substantial excitation pulse ringing signal in the second echo acquisition window.
U.S. Pat. No. 6,541,969 B2, issued to Sigal et al., discusses a method and system for improving the resolution of bore hole NMR logging measurements and for suppressing artifacts in NMR data obtained from logging measurements. In a preferred embodiment, the NMR pulse echo trains are CPMG spin echo trains. Further, non-formation signal contribution is estimated from two or more of the plurality of CPMG spin echo trains, preferably using one or more phase-alternated pair(s) of CPMG spin echo trains. In a specific implementation to PAPs are used that are formed by a current CPMG spin echo train (CPMG 0 ) and an immediately preceding (CPMG −1 ) and an immediately following (CPMG +1 ) phase alternated CPMG spin echo trains. In another embodiment, non-formation signal contribution is estimated using a separate NMR pulse echo train, which preferably is a CPMG spin echo train without an initial π/2 (excitation) pulse.
Another problem of the PAP approach as applied to NMR with logging arises from the inherent delay between sequences in the alternated pairs. Since the NMR device moves through the borehole during this delay, the echoes from the CPMG sequence can be measured in two environments having two different conductivities. Thus, the antenna response to the signal generated by magneto-acoustic effects can be different between the first and second obtained signal, and the ringing subtraction can become inaccurate as a result.
A technique addressing this problem is described in EP 0967490 A2, issued to Sun et al. Rather than employing PAPs, the method obtains a main signal comprising spin echo signals and undesired effects and then subtracts a signal from a second time period having only the undesired effects. Following the main part of the CPMG pulse sequence comprising echo signal, ringing and DC offset, the spin echoes are eliminated by using, for example, a missing 180° pull technique. The continuation of the allows for acquiring the ringing and DC offset only. The ringing and DC offset acquired during the second part of the sequence is averaged and then subtracted from the signal acquired during the main part. One drawback to this technique is that it consumes a substantial amount of DC power, and power consumption is critical for NMR well logging. Another drawback is related to the procedure employed for averaging the ringing signal, which operates using the assumption that the ringing signal repeat itself from echo to echo. This is not typically the case. Thus, the calculated average signal may not represent the ringing signal in a few first echo acquisition windows
There is a need to develop a method that reduces the effect of magneto-acoustic ringing in NMR experiments in a manner that minimally extends power consumption and can be operated in a region that sufficiently approximates the region in which signal detection occurs. The method of this invention addresses those needs.
SUMMARY OF THE INVENTION
The present invention is a method of reducing the effects of non-formation; signals in a nuclear magnetic resonance (NMR) echo signal obtained within a borehole in an earth formation. The method of the invention obtains an NMR echo signal sequence in response to a primary applied pulse sequence as well as at least one auxiliary signal pertaining to non-formation signal. The NMR echo signal typically carries formation and non-formation signals. The at least one auxiliary signal is in response to a single auxiliary pulse sequence applied at substantially the same depth as the primary pulse sequence and having at least an excitation pulse. The auxiliary sequence carries information on the non-formation signals. A sequence of signal responses is constructed from the at least one auxiliary signal in order to simulate the effective non-formation signal. The constructed signal is then subtracted from the NMR echo signal sequence.
The primary pulse sequence of the invention is preferably a Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence, having an excitation pulse following by a plurality of refocusing pulses. Preferably, the refocusing pulse of the primary pulse sequence further comprises a 180° reorientation pulse. Alternatively, the refocusing pulse can be of a length for reorienting atomic nuclei by an angle in a range between 90° and 180°.
The auxiliary pulse sequence comprises at least an excitation pulse of the CPMG sequence and preferably further comprises act least one refocusing pulse. Preferably, the auxiliary pulse sequence is of the form
TW a −90 ±x −( t cpa −B y −t cpa ) N a −90 ∓x
where TW a waiting time before the start of the auxiliary train; 90 ±x is an excitation pulse with RF carrier phase alternated; t cpa is the time interval between the excitation and refocusing pulses of the auxiliary pulse; B y is the refocusing pulse; 90 ∓x is a forced recovery pulse; and N a is the number of repetitions in the auxiliary train. The auxiliary pulse sequence is typically applied after a short time period (TW a ) after the end of the primary pulse sequence. The refocusing pulse (B y ) of the auxiliary pulse sequence can comprise a 180° reorientation pulse. Alternatively, the refocusing pulse of the auxiliary pulse can be a pulse for reorienting atomic nuclei by an angle in a range between 90° and 180°.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a well logging instrument suitable for use with the present invention.
FIG. 2 shows the ringing signal captured in a plurality of acquisition windows corresponding to a CPMG sequence.
FIG. 3 shows the ringing signal after a single refocusing RF pulse.
FIG. 4 shows the ringing signal after an excitation pulse.
FIG. 5 shows a constructed ringing signal computed according to the method of this invention.
FIG. 6 shows the results of subtracting experiment ringing signal from a ringing signal computed in FIG. 5 .
DESCRIPTION OF PREFERRED EMBODIMENT
FIG. 1 depicts a borehole 10 which has been drilled in a typical fashion into a subsurface geological formation 12 to be investigated for potential hydrocarbon producing reservoirs. An NMR logging tool 14 has been lowered into the hole 10 by means of a cable 16 and appropriate surface equipment represented diagrammatically a reel 18 and is being raised through the formation 12 comprising a plurality of layers 12 a through 12 g of differing composition, to log one or more of the formation's characteristics. The NMR logging tool is provided with bowsprings 22 to maintain the tool in an eccentric position within the borehole with one side of the tool in proximity to the borehole wall. The permanent magnets used for providing the static magnetic field is indicated by 23 and the magnet configuration is that of a line dipole. Signals generated by the tool 14 are passed to the surface through the cable 16 and from the cable 16 through another line 19 to appropriate surface equipment 20 for processing, recording and/or display or for transmission to another site for processing, recording and/or display.
FIG. 2 shows a plurality of ringing signals captured in a plurality of acquisition windows 205 corresponding to a CPMG sequence. Each acquisition window 205 has a duration of 0.15 ms. Acquisition windows are separated by the time interval TE=0.7 ms. Time is displayed in FIGS. 2-6 along the: abscissa in units of ms and the ringing is displayed along the ordinate on the scale of 10 −4 ADC units of voltage. The solid line 201 corresponds to the in-phase channels of the quadrature detector normally used in the NMR receivers. The dotted line 202 corresponds to the out-of-phase channel signal. The two signals can be considered as the real and imaginary parts of the complex vector representing the output voltage. Data in FIG. 2 is obtained with no hydrogen-containing sample coupled with the probe.
It is known that the amplitude of the acoustic excitation, produced either by an RF magnetic field in metal or by an applied electric field in dielectric material, follows a linear relation with respect to the RF field amplitude (see, for example, Buess et al.). A reasonable approximation can be made wherein the spurious signal, acquired in the NMR antenna in response to this acoustic excitation, is also linear with RF magnetic field strength. Thus, the ringing signal in the CPMG experiment can be reconstructed using the superposition principle given that the ringing signal from the excitation RF pulse and from a single refocusing RF pulse are known. The ringing signal in the echo acquisition window can be calculated according to the following equation:
R X , Y ( t ) = W ( t ) · [ R 90 X , Y ( t ) + ∑ i = 1 N R B X , Y ( t - T E / 2 - ( i - 1 ) · T E ) ] ( 2 )
with t>TE/2+(i−1)·TE, and where R 90X,Y (t) is the ringing signal after the excitation pulse with t=0 corresponding to the center of the pulse; R BX,Y (t−TE/2−(i−1)·TE) is the ringing signal obtained after application of the i th refocusing pulse; W(t) is the acquisition window function; N is the number of refocusing pulses used for the ringing signal acquisition; TE=2t cp is the time interval between the refocusing pulses. The width of the refocusing pulse is discussed in U.S. Pat. No. 6,163,153, issued to Reiderman et al., the contents of which are incorporated herein by reference. In a preferred mode of the invention, the ringing from the refocusing pulse R BX,Y is due to application of a 180° refocusing pulse. In an alternative, the refocusing pulse can lie within a range of, for example, a 90° pulse and a 180° pulse. Alternatively, the ringing signal due to the refocusing pulse can be determined by using the ringing from the excitation pulse.
The ringing constructed according to Eq. (2) is to be subtracted from the measured signal. In order to acquire ringing for R 90X,Y (t) and R BX,Y (t), an auxiliary pulse train containing at least one excitation and one refocusing pulse is employed. The TE used in the auxiliary train should be greater than that of the pulse train employed for the main NMR experiment in order to move the spin echo signal out of the ringing acquisition interval, thereby isolating the ringing effect. A plurality of refocusing pulses may be employed in the auxiliary train for the purpose of increasing the signal-to-noise ratio (SNR) through stacking of the ringing data. The time interval between refocusing pulses is preferably set to at least 3(TE+τ B ), where τ B is the refocusing pulse width used to isolate ringing effects.
FIG. 3 shows a ringing signal obtained after the application of a single refocusing RF pulse. A single acquisition window is used. The duration of the acquisition window for the single pulse ringing shown in FIG. 3 is 2 ms. The solid line 301 represents the in-phase component of the signal, and the broken line 302 represents the out-of-phase component of the signal.
FIG. 4 shows the ringing signal after the application of a single excitation pulse. The signal as shown is captured in acquisition windows for the first three echoes of a CPMG experiment. Acquisition intervals leave a duration of 0.15 ms and are spaced at an interval of TE=0.7 ms.
FIG. 5 presents a constructed signal computed according the method defined by Eq. (2). The solid line 501 represents the in-phase component of the signal, and the broken line 502 represents the out-of-phase component of the signal. The signal comprises ringing effects without echo signals. FIG. 6 shows a difference obtained by subtracting the experimental ringing signal shown in FIG. 2 from the reconstructed ringing signal of FIG. 5 . As FIGS. 2 and 5 are real and constructed ringing signals, the desired subtraction yields a signal that is substantially zero. The in-phase components are subtracted to yield the solid line 601 , which represents the difference in the in-phase components. Similarly, out-of-phase components are subtracted to yield the broken line 602 , which represents difference in the out-of-phase components. The residual ringing shown in FIG. 6 is substantially reduced towards zero.
The auxiliary train is typically of short duration compared to the main train and does not add significantly to the power consumption. In a continuously running NMR experiment, the auxiliary train should preferably be started soon after the end of the main train so that the nuclear magnetization can effectively return to equilibrium before, the next CPMG train is activated. To minimally disturb the magnetization it is preferable to employ a forced recovery pulse at the end of the auxiliary train. In this case, the auxiliary pulse train may be described as follows:
TW a −90 ±x −( t cpa −B y −t cpa ) N a −90 ∓x (3)
where, in addition to previously defined terms, TW a is waiting time before the start of the auxiliary train; t cpa is the time interval between the excitation and refocusing pulses of the auxiliary pulse; 90 ∓x is the forced recovery pulse; and N a is the number of repetitions in the auxiliary train.
In practice, a several options are possible for determination of the ringing signals from the excitation pulse and the refocusing pulse. Preferably, the ringing signal caused by the refocusing pulse is obtained using an auxiliary sequence that includes an excitation pulse followed by a refocusing pulse after a sufficiently long time interval (as discussed above so that the ringing caused by the excitation pulse is substantially zero at the time of the first echo following the refocusing pulse). The ringing signal due to the excitation pulse is also preferably obtained using the same auxiliary pulse sequence. Alternatively, the ringing signal due to the excitation pulse is estimated by using an additional auxiliary excitation pulse by itself.
In some practical cases the ringing patterns change relatively slowly compared to the expected changes of the echo signal (due to changing formation). Thus a method can be employed wherein the ringing signal produced by the auxiliary trains is averaged over a relatively long period of time compared to the duration of the echo signal. As the refocusing pulse ringing can be effectively eliminated by phase alternated pulse sequence, this method is more enabling for the excitation pulse ringing acquisition. While the foregoing disclosure is directed to the preferred embodiments of the invention, various modifications will be apparent to those skilled in the art. It is intended that all such variations within the scope and spirit of the appended claims be embraced by the foregoing disclosure.
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The invention is a method of reducing the effects of non-formation signals in an NMR logging echo signal obtained within a borehole in an earth formation. The method obtains a non-formation signal by the application of at least an excitation pulse, and preferably also at least one refocusing pulse. The obtained signal is used to numerically construct a synthetic ringing signal sequence. The constructed signal can then be subtracted from an NMR echo signal to reduce the effects of ringing.
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BACKGROUND OF THE INVENTION
The present invention relates to a device for the application and gluing labels to cylindrical containers.
Devices for applying labels to cylindrical surfaces of containers of the foregoing type are generally known. One of such devices is disclosed, for example in DE-AS No. 2,203,996. Various proposals have been made to save the amounts of glue utilized for the application of labels to cylindrical containers. It is superfluous to note that such known methods as covering with glue of complete surfaces of labels as well as the application of glue in a strip-like form onto the label have required huge amounts of glue in mass production.
Research has been made particularly with round labels to obtain gluing of the labels by applying glue only to the front end and the rear end of such label. Such arrangement, however, has presented constructive difficulties.
An experiment, which has been conducted wherein, in order to use cold glue in desired manner, the label box has been oscillated relative to the glue roll so as to coat the front and rear end of the label with glue, has failed because the oscillating masses in processing of large quantities of labels are not controllable.
It has been also attempted to use the stationary label container and to utilize a hot glue aggregate to apply glue to the front and rear ends of the labels being processed. However, hot glue is much more expensive than cold glue and the utilization of special heating aggregates has required such costs that this known method has been also found non-satisfactory in mass production.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved device for the application of labels, the front and rear ends of which are coated with cold glue, to the outer surfaces of cylindrical containers, for example cans or glass containers, which device would be suitable for mass production.
This and other objects of this invention are attained by a device for the application of labels to cylindrical containers, comprising conveying means for advancing cylindrical containers to a work position; separating means for positioning the cylindrical containers at equal intervals from each other on said conveying means; drive means and counter surface means for rolling said containers which are received from said conveying means at the work position; a gluing mechanism; label-containing box means; and a rotary label-transmitting drum positioned against said box means for removing an uppermost label from said box and transmitting said label along a periphery of the drum to said drive means and said counter surface means, said label-transmitting drum including at least one movable gripping segment which receives cold glue from said gluing mechanism and, upon the rotation of said drum, comes into contact with a front end of the uppermost label and takes said front end along upon a further rotation of the drum, and at least one stationary gripping segment which receives cold glue from said gluing mechanism and, upon rotation of said drum, comes into contact with a rear end of the uppermost label, said drum further including cam control means having a cam roller and a cam groove for guiding said cam roller, said cam control means controlling the movement of said movable segment when the latter is positioned against the front end of the uppermost label. Two movable gripping segments and two stationary gripping segments may be provided on the periphery of said drum, which are offset relative to each other by 180°.
If the length of the labels is equal or smaller than the length of the movable segment the latter may have immediate zones for applying glue to the front end and the rear end of the label being removed from said box means, then the stationary segment can be omitted.
The movable gripping segment may further include lever means and a gripping portion, said lever means connecting said cam roller to said gripping portion.
The lever means may include two pivotable levers having pivot points, which are arranged on the same circumference on said drum.
The lever means may include two pivotable levers having the pivot points, of which one pivot point is arranged on one circumference and another pivot point is arranged on another circumference on said drum, said one circumference being of a diameter which does not exceed the diameter of said another circumference by a maximal double diameter of said cam roller.
The lever means may further include a rod connecting said pivotable levers to each other.
The label-application device may further comprise a wiper at said work position and a counter pressure roller in the proximity of said box means, said movable segment under the influence of said cam roller and during the continual rotation of said drum transmits the uppermost label to said wiper, moves to said gluing mechanism to receive a new portion of cold glue therefrom, then comes into contact with a next uppermost label in said box means, moves into the stack of labels, performs a brief rearward-and-lifting movement and moves further to said wiper with the label stuck thereto whereas the stationary segment provided with glue from the gluing mechanism comes into contact with the rear end of said label and coats the latter with glue when the stationary segment passes by said counter pressure roller.
The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of the device for the application of labels onto continually rolling containers, according to the invention;
FIG. 2 is an enlarged schematic front view of the label-feeding drum in the first position A;
FIG. 3 is a schematic view of the feeding drum in the second position B;
FIG. 4 is a schematic view of the feeding drum in the third position C;
FIG. 5 is a schematic view of the feeding drum in the fourth position D;
FIG. 6 is a schematic view of the feeding drum in the fifth position E;
FIG. 7 is a schematic view of the feeding drum in the sixth position F;
FIG. 8 is a sectional view taken on line VIII--VIII of FIG. 9 and showing the feeding drum, with a device for moving a label-gripping segment, in relation with a gluing mechanism; and
FIG. 9 is a schematic view of the movable label-gripping segment of FIG. 8.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings in greater detail and firstly to FIG. 1 thereof, it will be seen that cylindrical containers 10, such as cans or glass containers, which are to be provided with the labels on the outer surfaces, are guided on a conventional conveyor belt 11 in the direction of arrow K. Containers 10 are then guided by a screw conveyor 12 so as to place them in the direction of feeding K at required equal intervals from each other before they reach a working region. Containers 10 are finally transmitted onto a driving belt 13 on which they are rolled and advanced between the outer surface of belt 13 and an actual counter surface 14 which may be made for example of foamed rubber. Counter surface 14 is positioned on a counter-hold device 15, the distance of which from the upper surface of belt 13 can be adjusted by means of an adjusting device 16 of any suitable conventional type in accordance with the diameter of the container being coated with a label.
Labels 17 are disposed in stack in a box 18. Labels 17 are transmitted from the stack in box 18 by means of a label-removing-and-transmitting drum 20. The latter includes a number of label-gluing and label-gripping segments 21 and 22 distributed over the periphery of the feeding drum 20. A gluing mechanism 19 of any suitable known type is positioned on the right-hand side of drum 20. Label-transmitting drum 20 is rotated in the direction shown by the arrow. Labels 17 glued and seized by the drum segments 21 and 22 are fed over the periphery of drum 20 to a wiper 23', which is positioned in the proximity of a deflection roller 23 of the driving belt 13, and then the labels are pressed against the outer surfaces of containers 10. Containers 10 rotate between the belt 13 and counter surface 14 so that upon a complete revolution of the individual container the label wraps around the periphery of this container and sticks to that periphery. The gluing mechanism 19 has a surface feeler 24. A safety cover 25 is positioned against the screw conveyor 12. A stopper 26 serves for an instant placing of the device out of operation.
Label-gripping and transmitting segments 21 and 22 are arranged so that upon one rotation of the feeding drum 20 two containers can be provided with labels. Therefore the output of 30,000 cans or containers per hour can be obtained with 250 revolutions per minute.
Segments 21 are movable relative to the drum 20 and serve to coat with glue front ends of the labels removed from the stack while segments 22 are stationary relative to drum 20 and serve for applying the glue received from the gluing mechanism 19 to the rear ends of the labels transmitted from the stack onto the periphery of the feeding drum 20. Cold glue is applied onto the outer surfaces of segments 21 and 22, rotated together with drum 20, from the gluing mechanism 19 in the conventional fashion.
With reference to FIGS. 2, 8 and 9 it will be seen that each movable label-gripping segment 21 is mounted on a mechanism which imparts to segment 21 the movement which will be explained below. This mechanism includes two pivotable levers or rods 32 and 33, each pivotable on a respective pivot 40 or 39, and connected to each other by an intermediate rod or lever 34. Lever 33 is connected to a cam follower 31 which is guided in a cam groove formed between the parallel cam faces of a control cam 30. Pivot points 40 and 39 of levers or rods 32 and 33 are positioned on a common circumference 38. Cam 30 has a cam surface 35 and a cam surface 36.
Referring back to FIG. 1, reference numeral 23 designates a deflection roll of the conveyor belt 13, reference numeral 27 denotes a coding sensor, 28 is any suitable data-applying device for a horizontal and vertical labelling on a front end of the label transmitted by drum 28, and 29 is a pressure roller.
Movable segment 21 is displaced under the influence of the control cam 30 in the different consecutive states so that different working positions A to F result which are illustrated in FIGS. 2 to 7.
In the position A shown in FIG. 2 the cam face 35 of the cam guide causes an oscillation of segment 21 in the forward direction toward the front end of the uppermost label 17 positioned in box 18.
In the position B of FIG. 3 the segment 21 carrying a glue thereon, which was previously applied to its outer surface from gluing mechanism 19, contacts the front end of the uppermost label, as it is again guided by the control cam 30 and levers 32, 33, 34 while the pivot points 39 and 40 remain on the circumference 38.
In the position C of FIG. 4 segment 21 is pressed with its outer surface into the label stack.
In the position D shown in FIG. 5 the counter cam surface 36 of the control cam 30 causes segment 21 not only to start lifting off together with the uppermost label stuck thereto but also simultaneously to perform a brief rearward movement to permit the segment 21 with the label's end to slide over a projection 37 on the label box 18.
In the position E of FIG. 6 movable segment 21 moves again forwardly and takes along the uppermost label 17 onto the periphery of the feeding drum 20.
In the position F depicted in FIG. 7 the label front end coated with glue and transmitted by segment 21 over the periphery of the rotating drum 20 arrives at the wiper 23' and the label 17 is conveyed by deflection roll 23 of the running drive belt 13 onto the container 10 which is in the work position. Container 10 at this point rolls between the outer surface of driving belt 13 and counter surface 14 whereby it is wrapped around by label 17. Meanwhile the stationary segment 22 arrives against the end of the uppermost label 17 in the stack. Stationary segment 22 applies glue with the aid of counter pressure roller 29 to the rear end of the uppermost label and takes this rear end along to convey it to the wiper 23' whereby the rear end of the label also reaches the container 10 and the wrapping of the label around container 10 is completed. As mentioned above glue was applied to the stationary segment 22, before it had reached the stack of labels in box 18, from the gluing mechanism 19.
Mechanisms for controlled movement of the movable segment 21 relative to the label stack and including rods 32, 33, 34 can be of course formed in any other suitable fashion.
The advantages of the labelling machine for applying labels to cylindrical containers, such as cans and glasses, are as follows:
The gluing of the front and rear ends of the labels is carried out by cold glue-applying mechanism instead of hot glue aggregates;
About 85% to 90% of glue saving can be achieved as compared to the conventional methods of gluing the entire label or of applying strips to the labels;
Containers 10 are guided through the machine in a straight-line orientation which requires very little space and simple supporting means;
Means for transmitting labels from the stack box to the containers are very simple, and not only a small transmission moment is obtained but also a quick adjustment to various label formats is possible;
The horizontal and vertical signs on the front side of each label positioned on the drum 20 can be applied by means of data-application device 28 or the like;
A coding sensor or reader 27 can be provided on drum 20;
Due to the provision of the stationary label box or container 18 oscillating masses are avoided and an easy insertion of longer labels into the box during the operation can be made possible; and
The containers 10 are held and guided during the entire labelling process.
It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of devices for the application of labels to cylindrical containers differing from the types described above.
While the invention has been illustrated and described as embodied in a device for the application of labels to cylindrical containers, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention.
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A device for the application of labels onto the periphery of cylindrical containers, which are advanced at intervals from each other, comprises a continually rotating drum which carries a stationary gripping member and a movable gripping member, which receive cold glue from a glue supply device and grip the uppermost label from the stack of labels to transmit this label to one of the advanced containers. The movable gripping member is movable under the control of a cam arrangement toward the front end of the label being transmitted and carries that front end therealong whereas the stationary gripping member while passing the rear end of the label applies glue to that rear end.
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BACKGROUND OF THE INVENTION
Test fixtures are used in association with downhole tools during the uphole testing of the downhole tools. One such downhole tool is a downhole power unit. A downhole power unit is an electro-mechanical device that is designed to produce a linear force for setting (or pulling) wellbore tools such as monolocks, bridge plugs, packers and the like. A shaft extending axially from the end of the downhole is utilized to transmit this force. The downhole tool is tested uphole prior to insertion downhole to calibrate the tool and ensure that the tool can exert the appropriate amount of force via the shaft as required for a particular application, such as, for example, setting a packer having a 60,000 lb f activation threshold.
During these tests, using shear pins, the test fixture is attached to the end of the rod extending from the downhole tool. An axial force is applied to the test fixture via the rod until the shear pins fail. As a result of the high testing forces imposed on the test fixture by the rod, the test fixture is forcibly expelled from the downhole tool at a high velocity. Likewise, portions of the shear pins are separated from the test fixture during the process. Both the separated text fixture and the shear pins can present danger to personnel in the area of the tests.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete understanding of the present disclosure and advantages thereof may be acquired by referring to the following description taken in conjunction with the accompanying figures, wherein:
FIG. 1 schematically depicts a downhole power unit and test apparatus for use in the uphole testing of the power unit, the test apparatus including a test fixture and a specially designed safety structure operative to partially surround and catch the test fixture, and associated shear pin portions thereof, when the fixture is released from the power unit during the test;
FIG. 2 is a top side perspective view of the safety structure with a pivotally mounted side wall portion thereof in a closed position;
FIG. 3 is a perspective view of the side wall portion removed from the safety structure;
FIG. 4 is a perspective view of the safety structure with the side wall portion removed therefrom;
FIG. 5 is a side elevational view of the power unit operatively coupled to the test fixture in preparation for the uphole test of the power unit using the safety fixture, a portion of which is schematically shown in phantom in FIG. 5 ;
FIG. 6 is a top side perspective view of the power unit/test fixture assembly of FIG. 5 with the safety structure operatively mounted on the power unit and partially surrounding the test fixture;
FIG. 7 is an enlarged scale simplified cross-sectional view, partially in elevation and partially in phantom, taken through the FIG. 6 apparatus generally along line 7 - 7 and illustrating the operation of the test apparatus; and
FIG. 8 is a simplified cross-sectional view through an alternative embodiment of the test fixture and illustrates its use in testing the power unit and providing for calibration thereof.
DETAILED DESCRIPTION
In the detailed description of the invention, like numerals are employed to designate like parts throughout. Various items of equipment, such as pipes, valves, pumps, fasteners, fittings, etc., may be omitted to simplify the description. However, those skilled in the art will realize that such conventional equipment can be employed as desired.
In general, a downhole tool is operable to selectively generate a linear force that may be used to set wellbore devices such as packers and plugs. The downhole tool is tested uphole prior to insertion downhole to calibrate the tool and ensure that the tool can exert the desired amount of force for a particular application, such as, for example, setting a packer having a 60,000 lb f activation threshold. As will be described in greater detail below, one or more shear pins are used in the testing process and incorporated in a test fixture to simulate the activation threshold for a particular application. In this example, a plurality of shear pins are used to simulate the 60,000 lb f activation threshold. The shear pins are selected to shear under application of an axial force once the threshold is reached. For example, twelve shear pins may be used with each shear pin rated at 5,000 lb f so that the total force required to shear is 60,000 lb f . Upon shearing of the pins, the sheared pins and test fixture are forcibly expelled from the tool at a fairly high velocity. The safety structure of the present invention is positionable on the downhole tool so as to partially surround the test fixture in order to catch and retain the test fixture and the pieces of the shear pins expelled from the tool, thereby enhancing the safety of personnel working near the test site.
Referring to FIG. 1 , schematically depicted in an exemplary embodiment, is a downhole tool 10 to selectively generate a linear force on a testing apparatus 11 . In the exemplary embodiment, the downhole tool 10 is a downhole power unit, however, the downhole tool could be other types of tools consistent with the uses of the safety structure. The testing apparatus 11 includes a test fixture 12 and a safety structure 14 . The power unit 10 , as is known to one of ordinary skill in the art, is operable to axially extend or retract a rod 16 out of an end 17 of the power unit 10 in order to, for example, operate wellbore devices such as plugs and packers (not shown). The power unit 10 may include electrical power leads 18 and/or data transmission leads 20 . During uphole testing, the power unit 10 is preferably supported in horizontal position by suitable stands (not shown), as is known to one of ordinary skill in the art. A collar 22 may be mounted around the end 17 of the power unit 10 in order to aid in the testing of the power unit.
The outer body of test fixture 12 is of a tubular configuration and includes one or more, and preferably a plurality, of radial holes or apertures 24 . In one preferred embodiment, sets of radial holes 24 are aligned with one another and positioned to form a ring about the circumference of the test fixture body. The test fixture 12 is configured to retain a piston member (not shown in FIG. 1 , but explained in greater detail below) within its interior using shear pins 26 passing through apertures 24 . As will be explained in greater detail below, the piston member also is threadingly connected to the rod 16 of the downhole tool 10 .
At the distal end, the safety structure 14 includes a cylindrical, hollow test fixture retaining section 30 that is disposed to partially surround the test fixture 12 when the safety structure 14 is mounted on the power unit 10 . At the proximal end, the safety structure 14 includes a cylindrical tool mounting section 31 . Preferably, the distal end of safety structure 14 is closed while the proximal end of safety structure 14 is open. The safety structure 14 attaches to the power unit 10 through the use of the cylindrical tool mounting section 31 which includes a pivotal side wall portion 32 . The side wall portion 32 is secured by hinges 34 and pivots open so that the cylindrical tool mounting section 31 can be disposed around an end portion of the power unit 10 . The side wall portion 32 is then closed over the power unit 10 to securely fasten the safety structure 14 to the power unit 10 .
The tool mounting section 31 is shown in FIGS. 1 and 2 with the side wall portion 32 in a closed position. The side wall portion 32 may be secured in a closed position with any suitable fastener, such as for example, the illustrated bolt 38 and nut 40 . The tool mounting section 31 , i.e., the proximal end of safety structure 14 , has a smaller diameter than the cylindrical test fixture retaining section 30 , i.e., the distal end of safety structure 14 . A frustoconical section 36 connects and supports the tool mounting section 31 to the cylindrical test fixture retaining section 30 . An optional top side opening 42 may be provided and extends along the sections 30 , 31 and 36 as shown. The opening 42 covers approximately 180 degrees of the circumference of the tapered diameter section 36 and the test fixture retaining section 30 and occupies the entire axial length of the tapered diameter section 36 and approximately one-third of the axial length of the test fixture retaining section 30 .
The opening 42 aids in the mounting and removal of the safety structure 14 to and from the assembly of the power unit 10 and the test fixture 12 . The opening 42 also permits access to and in some embodiments retrieval of the test fixture 12 and shear pins without removing the safety structure 14 from the power unit 10 .
Referring to FIG. 3 , the side wall portion 32 includes a half-cylindrical body 44 with a latching mechanism 46 , such as a plate, mounted on the exterior of one side near the edge of the axial length wise dimension of the half-cylindrical body 44 . In one preferred embodiment, the latching mechanism 46 has a U-shaped opening 48 formed in a plate which opening is configured to receive bolt 38 . Mounted on the other edge of the axial length wise dimension of the half-cylindrical body 44 are hinge components, such as plates 50 and 51 . Plates 50 and 51 each contain an aperture 52 so as for form hinge 34 . Those skilled in the art will appreciate that while side wall portion 32 is preferable for securing safety structure 14 to downhole tool 10 , other structures and mechanisms are also suitable for this purposes, such as for example, bands that wrap around the circumference of tool 10 .
Referring to FIG. 4 , the safety structure 14 is shown with the side wall portion 32 removed. The safety structure 14 may include complimentary hinge elements. In the preferred embodiment, such hinge elements are two pairs of plate sets mounted on the exterior of an edge of the axial length wise dimension of the tool mounting section 31 to form devises 53 and 55 . The devises 53 and 55 will receive the two plates 50 and 51 mounted on the side wall portion 32 so that the apertures 52 and the apertures of the devises (not shown) are aligned. A pin (not shown) may then be inserted into the aligned apertures to form the hinges 34 .
The safety structure 14 also includes a third pair of plates 57 mounted on the exterior of the other edge of the axial length wise dimension of the tool mounting section 31 . The bolt 38 is rotatable mounted within this third pair of plates 57 . A circular plate 54 is connected to the rear end of the test fixture retaining section 30 to close the far end 56 of the safety structure 14 .
Referring to FIGS. 5-7 , in an exemplary embodiment, test fixture 12 is shown attached to power unit 10 . Likewise, safety structure 14 (shown in phantom in FIG. 5 ) is attached to the power unit 10 and positioned to partially surround test fixture 12 . FIG. 6 illustrates a top side perspective view of the safety structure 14 operatively mounted on the power unit 10 and partially surrounding the text fixture 12 . Power unit rod 16 has an outer end 58 that is threadingly connected to a piston 60 releasably held within the tubular body of the test fixture 12 by the shear pins 26 . The interior of the test fixture body has diameter that is larger than the outside diameter of the piston 60 , thereby permitting axial movement of piston 60 when not secured in place by shear pins 26 . As mentioned above, the tubular body of the test fixture 12 preferably includes a plurality of aligned radial apertures 24 located in a ring about the circumference of the test fixture. As illustrated in FIGS. 5 and 8 , there may be two such rings in some embodiments, each set of apertures corresponding to a separate piston secured within test fixture 12 . In any event, piston 60 includes a plurality of corresponding apertures 61 for receipt of shear pins 26 when apertures 61 and 24 are aligned. Piston 60 may also include a cavity 62 configured to receive the ends of shear pins 26 that are pressed through the aligned radial apertures 24 and 61 . After the shear pins 26 are pressed through the radial apertures 24 of the test fixture 12 and into the corresponding apertures 61 of the piston 60 , the piston is secured to the test fixture 12 . The rod 16 of the power unit 10 is shown retracted into the power unit 10 so that one end of test fixture 12 abuts the collar 22 of the power unit 10 , preferably without interfering with the extended threaded end of tool 10 .
The safety structure 14 is mounted to the power unit 10 so that the safety structure 14 partially surrounds test fixture 12 , as shown in FIG. 6 , by opening the pivotally mounted side wall portion 32 and placing the tool mounting section 31 around a portion of the cylindrical body of the power unit 10 . The pivotally mounted side wall portion 32 may then be closed over the power unit 10 and secured in place by engaging bolt 38 with the U-shaped opening 48 of the plate 46 and tightening the nut 40 onto the bolt. The safety structure 14 is positioned on the power unit 10 so that the opening 42 is facing substantially upward relative to the horizontal.
Still referring to FIG. 7 , during testing of the power unit 10 , the power unit 10 exerts a force to retract the rod 16 within the power unit, in the direction of arrow 64 . The test fixture 12 , because it is ultimately attached to the rod 16 through the engagement of the rod by the piston 60 and the piston is secured to test fixture 12 via shear pins 26 , will then move in the direction of arrow 64 until the end of the test fixture abuts collar 22 of the power unit 10 . After the test fixture 12 abuts collar 22 of the power unit 10 , continued retraction of rod 16 by the power unit 10 results in an increasing amount of force exerted by the power unit 10 on the piston and shear pins 26 until the axial force exceeds the shear force breaking point of the shear pins 26 , thereby causing the shear pins 26 to shear and the piston 60 to be released from its fixed position within test fixture 12 . Typically, the amount of force required to shear the shear pins 26 often causes the test fixture 12 to be forcibly expelled, after the shear pins 26 break, in a direction away from the power unit 10 , as indicated by directional arrow 66 . After pins 26 shear, the piston 60 and rod 16 may continue to move axially in the direction of arrow 64 towards the power unit 10 . The movement of the piston 60 in the direction of arrow 64 and the movement of the test fixture 12 in the direction of arrow 66 results in release of the test fixture 12 from engagement with piston 60 and rod 16 , such that test fixture 12 will be ejected from the end of power unit 10 and settling within the test fixture retaining section 30 of the safety structure 14 . In addition to safely “catching” the expelled test fixture 12 , the safety structure 14 also serves to “capture” the pieces of the shear pins 26 after the shear pins break.
Referring to FIG. 8 , in another embodiment, a test fixture 70 includes two circumferential rows of aligned radial apertures 24 . The two rows of aligned radial apertures 24 allow the use of the piston 60 and a second piston 72 which are both connected to the test fixture 70 through the use of shear pins 26 . The second piston 72 has a bore 74 with an internal diameter that is larger than the external diameter of the rod 16 , allowing the rod 16 to pass through the second piston 72 . The rod 16 is connected in a suitable manner to piston 60 , and as described above, may be threadably connected to the piston 60 .
Testing of the power unit 10 with the test fixture 70 is similar to the procedure described above. After the rod 16 is retracted within the power unit 10 so that the test fixture 70 abuts the power unit 10 , the power unit 10 increases the force on the rod 16 until the shear pins 26 attaching the piston 60 to the test fixture 12 shear and allow piston 60 to move in the direction of arrow 64 . The power unit 10 continues to retract rod 16 in the direction of arrow 64 until the piston 60 abuts the second piston 72 . The power unit 10 then again increases the force on the rod 16 until the shear pins 26 attaching the second piston 72 to the test fixture 12 shear and allow the piston 60 , the second piston 72 , and rod 16 to move in the direction of arrow 64 .
The use of text fixture 70 along with second piston 72 allows an operator of the power unit 10 to make an initial test and measure, for example, how much electrical current is required in order to shear the shear pins 26 connecting the piston 60 to the test fixture 12 . The measured electrical current value then corresponds to a known force value because the force value is known from number of shear pins and the force rating for each shear pin. For example, if twelve shear pins are used and each pin is rated for 5,000 lb f , then the current value measured at the time the shear pins break corresponds to 60,000 lb f . A force regulating device of the power unit 10 can be calibrated to use the measured current value for the known force value. The second piston 72 is attached with an identical number of identical shear pins and a second test is performed with the second piston 72 that allows the operator to verify that the current measured with piston 60 will shear the equivalent rated shear pins on piston 72 and that the power unit 10 is properly calibrated.
While certain features and embodiments of the invention have been described in detail herein, it will be readily understood that the invention encompasses all modifications and enhancements within the scope and spirit of the following claims. Furthermore, no limitations are intended in the details of construction or design herein shown, other than as described in the claims below. Moreover, those skilled in the art will appreciate that description of various components as being oriented vertically or horizontally are not intended as limitations, but are provided for the convenience of describing the invention.
For example, the test fixture is described as cylindrical in shape, although other shapes of the test fixture may be used. In addition, it is not necessary that a piston inside of a cylindrical test fixture be utilized, rather, the rod may be directly connected to the test fixture via shear pins. It is also not necessary that shear pins be utilized to secure the rod (either directly or indirectly) to the test fixture. Devices other than shear pins are contemplated to provide a targeted separation force between rod and the test fixture. For example, test fixture 12 may be provided with an enclosed distal end and one or more bolts having known axial tensile rupture limits may secure the rod to the test fixture. Upon application of an axial force by the rod, the bolts will axially rupture at a known tensile value. Thus, the invention is not limited to a particular type of rupture separation between the test fixture and the power unit.
Likewise, the safety structure need not be of cylindrical construction. The opening 42 need not be provided, rather, a fully enclosed structure could be provided that uses a panel that can be opened to retrieve the test fixture and shear pins following a test. The tool mounting section of the safety structure also does not need to have a pivotally mounted side wall portion in order to attach to the downhole tool, other forms of attaching to the downhole tool are contemplated.
It is therefore evident that the particular illustrative embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the present invention. Also, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee.
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A safety apparatus for catching a test fixture released from a shaft of a downhole tool during the uphole calibration and testing of the shaft force generation capability of the tool. The safety apparatus includes a hollow body having a distal end that will partially envelope the test fixture to catch the test fixture once the test fixture is released from the downhole tool. The safety apparatus further includes a proximal end portion that is releasably securable to the body of the tool. A method for testing and calibrating the tool is also provided.
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FIELD OF THE INVENTION
The present invention relates to a means to increase the depth range of an underwater pressure hull such as an underwater camera without increasing the strength of the structure or seals.
BACKGROUND OF THE INVENTION
Recent achievements in the microprocessor control field have led to the development of underwater cameras which utilize the basic camera case as the pressure hull. The majority of cameras of this type have a maximum operating limit from 3 to 10 meters. Operations within this range are accomplished with minimal changes to the basic camera bodies and therefore the camera price may be held low.
A few attempts have been made to increase the strength of the structure of the camera body so that the cameras may be utilized at greater depths and therefore render the cameras more practicable for underwater use. The maximum depth obtainable by increasing the camera structure is approximately 30 meters but the increased costs necessitated by the stronger camera body more than triples the retail cost of the camera, placing it out of range for the average sport diver.
OBJECTIVES OF THE INVENTION
Considering the shortcomings of the existing underwater cameras, it is a primary objective of the invention to provide a means whereby the operating depth of an underwater camera may be increased without increasing the physical structure.
Another objective of the invention is to provide a method for operating an underwater camera where the camera body is pressurized prior to commencing a dive.
A still further objective of the invention is to provide an underwater camera including means to pressurize the internal camera body in response to ambient pressure encountered during a dive.
Another objective of the invention is to provide a collapsible means to effectively increase the internal volume of an underwater camera. The collapsible means collapses due to the water pressure during a dive and thereby pressurizes the camera body and extend the operating depth of the camera.
SUMMARY OF THE INVENTION
The present invention contemplates a means to pressurize the interior of a pressure hull such as an underwater camera body combined with a pressure relief means whereby the camera body may be pressurized to a point below that which distortion of the body will occur. This point is approximately equal to the design operating depth of the camera body and the pressurization therefore results in doubling the depth at which the camera may be utilized.
In one embodiment of the invention, the pressurization port of the camera is attached to the second stage regulator of the diver's scuba system by a one-way valve. This pressurizes the camera to approximate ambient water pressure with each breath the diver takes. Thus there is no limit to the depth at which the camera may operate except for the limitations of the diver.
In another embodiment of the invention, a collapsible container is attached to the pressurization port of the camera body to increase the effective interior volume. As the camera is submerged, the body is collapsed to equalize the pressure within the camera. When the body is completely collapsed, the internal camera pressure equals the ambient water pressure. The camera then has the added depth range equivalent to its basic structural rating.
A still further embodiment is contemplated where the collapsible body is fabricated from a material which precludes expansion if the body is pressurized but will not interfere with the ready collapse under water pressure. By pressurizing this system, the operating depth of the camera can be greatly increased without adding excessive bulk to the accessory air volume storage means.
In a preferred embodiment, a hollow handle containing an inflatable bladder is secured to the camera body. The bladder is connected to the camera pressurization port and provides a source of pressure equalization gas.
In a still further embodiment, a handle includes a cylinder connected to the camera pressurization port. The other end of the cylinder is open. A free piston in the cylinder slides in response to the differential pressure between the camera body and ambient water pressure to equalize the internal pressure during descent or ascent.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of a camera illustrating the pressurization and pressure relief valves.
FIG. 2 is bottom view of a camera illustrating the pressurization and relief valves.
FIG. 3 is a front view of an underwater camera with a collapsible, auxiliary air volume attached.
FIG. 4 is a side view of an underwater camera with a collapsible, auxiliary air volume apparatus attached. The dashed lines illustrate the collapsed configuration.
FIG. 5 is a front view of an underwater camera with a collapsible, auxiliary air volume apparatus attached illustrating in dashline the apparatus collapsed and rolled up.
FIG. 6 is a side view of an underwater camera with a collapsible, auxiliary air volume apparatus attached illustrating in dash line the apparatus collapsed and rolled up.
FIG. 7 illustrates an underwater camera with a pressurization equalization line attached to the low pressure, second stage regulator of a scuba apparatus.
FIG. 8 illustrates an underwater camera with a pressurization line connected to the low pressure output of the first stage regulator of a scuba system.
FIG. 9 illustrates an underwater camera with a pressure equalization line connected to a collapsible bladder located in a remote container.
FIG. 10 illustrates an underwater camera with a hollow hand grip containing a collapsible bladder.
FIG. 11 illustrates an embodiment of the basic invention which includes a pressure responsive pump for pressurizing the camera case.
FIG. 12 illustrates the use of a pair of pressure responsive pumps for pressurizing an equipment pressure hull.
DESCRIPTION OF THE INVENTION
FIG. 1 illustrates a typical underwater camera with the camera body or case 10 used as the pressurization hull. The case is modified by including a one-way, pressurization valve 11. This valve may be similar to a common tire valve and its purpose is to allow the camera case to be pressurized by a simple hand pump or compressed air source. A pressure relief valve 12 is included in the camera body to prevent over pressurization of the camera. The use of a pressure relief valve simplifies pressurization by allowing an operator to apply a compressed air source to pressurization inlet valve 11 until safety valve 12 opens. Cap 13 seals the pressurization inlet valve 11 during dive operations to prevent water from entering the camera body when the external pressure exceeds the internal pressure.
This system allows operation of the camera at greater than design depths. For instance, the Cannon Aqua Snappy has a body with an operating design depth of one atmosphere or approximately 33 feet. According to this embodiment of the invention, the camera may be pressurized to at least that value. Thus the pressure relief valve 12 is set to open at one atmosphere above ambient. The camera body is pressurized until the relief valve opens to ensure that the internal pressure is one atmosphere above ambient. A protective cap 13 is placed over the pressurization inlet port 11 and the camera is ready for underwater operations. When the camera is submerged to its normal design structural limit of 33 feet, the pressure within the camera equals the external pressure of one atmosphere greater than sea level so there is no stress on the camera body. The camera may safely be submerged an additional 33 feet which places the camera at its new maximum operating depth which is a real pressure of three atmospheres. However, because the camera was pressurized to one atmosphere above sea level ambient pressure, the differential pressure at 66 feet is only one atmosphere and the camera is within its operating range.
The safety pressure relief valve 12 may include a manual pressure relief valve 14. This valve allows an operator to manually release the camera pressure so that the camera body may be opened to change film. In a preferred embodiment, the manual pressure relief valve 14 is recessed and requires a smaller diameter rod for actuation to preclude inadvertent operation while the camera is submerged.
FIG. 2 is a bottom view of the embodiment discussed above.
FIG. 3 illustrates an alternate embodiment where a collapsible air container 20 is attached to air inlet port 11. In this embodiment, the one-way valve within air inlet port 11 is removed to allow the free exchange of pressure between the camera body 10 and auxiliary air container 20.
In a typical operation, air container 20 has a volume equal to the volume within the camera body. In this embodiment, pressure relief valve 12 is not necessary because the camera will never become over pressurized. As the camera is submerged, container 20 collapses to maintain the air pressure within the camera body 10 equal to the external water pressure. In the exemplary case, the container 20 has a volume equal to the interior of the camera case, when the camera has been submerged to a depth of 33 feet or one atmosphere, the container 20 is completely collapsed as illustrated by dashed lines in FIG. 4 and the differential pressure between the camera and the water is zero. The camera may now be submerged to a point where the differential pressure between the camera and the exterior equal the original design depth. If desired, container 20 may have a volume greater than the volume of the camera body to permit even deeper descents. For instance, if a Nikon Action Touch camera with a design depth of only 3 meters is fitted with a container 20 having an internal volume equal to four times the internal volume of the camera, the normally shallow water camera may be operated at depths as great as 140 feet.
The preceding operations are presented as being exemplary of a system which utilizes a camera body having a one-third atmosphere operating pressure differential. If the camera body strength is greater, the benefits of this invention are appropriately increased while if the operating differential pressures are less, the basic benefits of the system are likewise reduced.
Container 20 and attached camera body 10 may be pressurized through one-way valve 21. This valve is similar to that utilized in the embodiment illustrated in FIG. 1 or it may be a ball inflation valve of the type requiring a hollow needle. In this embodiment, the pressure relief valve 12 is a desirable item to prevent over pressurization of the camera body. Air bag 20 is fabricated from a material which is reinforced in such a manner that it will readily collapse but will not significantly expand when pressurized.
Assuming a camera case 10 capable of withstanding a differential pressure of one atmosphere such as the Cannon Aqua Snappy, the container/camera body is pressurized to the pressure differential limits of the camera body. When the camera is submerged to a depth of 33 feet or one atmosphere, the differential pressure is zero and the air bag 20 is on the verge of beginning to collapse. The camera may be submerged an additional 33 feet or to a total of 66 feet and upon reaching that depth, the air bag 20 has completely collapsed as illustrated by the dashed line representation 22 of FIG. 4 but the differential pressure which the camera body 10 is experiencing is still zero. The camera body may now be submerged an additional 33 feet to 99 feet (four atmospheres) where it experiences its maximum design depth limit differential of one atmosphere.
FIGS. 5 and 6 are front and side views of an embodiment illustrating an auxiliary air chamber 30 which includes a coiling means whereby the container rolls into a coil as it collapses. The inflated configuration of the air container is illustrated by solid lines 30 in the figures and the collapsed, rolled condition is illustrated by dashed lines 32. Container 30 may be used exactly as described for container 20 illustrated in FIGS. 3 and 4.
FIG. 7 illustrates a still further embodiment of the invention. The camera body 10 is pneumatically coupled to the second stage regulator 40 of a self-contained underwater breathing apparatus. In the illustrated embodiment, a Nikon Action Touch camera having a design operating depth of 3 meters is modified by replacing the battery cap with a battery cap 43 having an air inlet port 41. The air inlet port may be similar to that illustrated in FIGS. 1 through 6 so that the camera may operate as illustrated in those embodiments. In the illustrated embodiment of FIG. 7, the air inlet port 41 is a hollow tube to which a heavy walled, small diameter neoprene tubing 42 is sealed to provide a pneumatic conduit to the second stage regulator 40.
The second stage regulator fitting includes a one-way valve 43 which protects the integrity of the breathing apparatus in the event of a malfunction of the camera or if the tube 42 is severed or torn loose. The one-way valve 43 allows air from the low pressure regulator 40 to pass through tubing 42 into the camera body but will prevent water from entering the regulator in the event that tube 42 is removed. The one-way valve is coupled to the second stage regulator 40 via a chamber 44 which may be filled with a desiccant 45 such as silica gel. The chamber is sealed to the second stage regulator and includes a termination inlet port 46 which contains a gas permeable vapor barrier 47. Air inlet port 46 is larger in diameter than the tubing to accommodate the greater surface area required to allow reasonable free passage of air from the second stage regulator into the conduit to the camera via the restriction of the gas permeable vapor barrier 47. This material will allow air to pass into the camera but prevent moisture from entering the system.
FIG. 8 is an alternate embodiment usable with pressure hulls having a design strength capable of withstanding a pressurization equal to the low pressure output of the first stage regulator of a scuba system. In this embodiment, air line 52 is connected to a low pressure outlet of the first stage regulator 50 in much the same fashion as used to connect buoyancy controlled devices or second stage regulators to the first stage regulator of a scuba system. A quick release fitting 51 is used so that the operator may disconnect the system in the event of a failure of the line 52, pressure relief valve 12 or camera to prevent the total loss of air through the resultant open low pressure outlet.
In the embodiments illustrated in FIGS. 7 and 8, the pressure relief valve 12 automatically depressurize the pressure hull as the camera is raised to the surface. If the embodiment illustrated in FIG. 7 is modified by removing the one-way safety valve 43, the camera will automatically depressurize through the second stage regulator and safety valve 12 is not required.
The embodiments illustrated in FIGS. 7 and 8 will allow a diver to take the camera to any depth that the diver can survive.
In the embodiment illustrated in FIG. 7, a shallow water camera, such as the Nikon Action Touch camera which has a design depth of only 3 meters, may be used with comparative safety at any depth to which the diver can survive because the differential pressure between the camera and the ambient water pressure will remain at zero.
FIG. 9 illustrates an embodiment which will allow a camera to be taken to depths equal to many times the design depth of the camera. It includes an air bladder 60 within a container 63 which may be strapped to the diver or the diver's apparatus. The air bladder may be large relative to the camera to permit operation at extreme depths. The air bladder 60 is coupled to the camera 10 via air line 62 and coupling 61 in a manner similar to that described for the embodiments illustrated in FIGS. 7 and 8. In the embodiment of FIG. 9, a pressure relief valve is not necessary because the camera will equalize on descent by the collapse of air bladder 60 and on ascent by the expansion of the air bladder.
FIG. 10 is a further adaptation of the embodiment illustrated in FIG. 9 where the container or bag 70 is shaped in the form of a hollow handle 73 that may be secured to the camera body by the tripod attachment means 74. In this embodiment, a short air line may be used to couple bladder 70 to the camera or the bladder may be fitted with a sports ball needle valve 75 positioned to engage a hollow needle valve 76 threaded into the body of the camera. In the embodiment illustrated in FIG. 10, the battery cap 77 of the camera may be modified by boring a hole therethrough and tapping a 5/16-32 thread therein. The sports ball needle valve 76 may be threaded into the modified battery cap so that air bladder 70 will be connected directly to the camera through needle 76 by valve 75. The tripod retaining screw 78 holds the assembly securely to the base of the camera body 10 and bladder 70 is secured to the interior of the handle in the vicinity of valve 75 so that the bladder will not pull free from the valve needle 76 in the event that the camera is held underwater with the handle in the up position while the bladder is partially collapsed.
FIG. 11 illustrates an embodiment of the invention which uses a free piston pump 80 to pressurize the camera. The pump cylinder is pneumatically coupled to the air inlet of the camera body 81. The other end 84 of cylinder 80 is open to the ambient environment and a free piston 82 provides a movable gas tight seal within the cylinder. In operation, the free piston 82 is positioned at the end 89 of the cylindrical chamber 83 to provide a maximum volume between the upper surface of free piston 82 and the inlet port 81. The piston may be manually pushed into the extreme lower position by a rod or light spring 84 or simply by adding air pressure to the outlet port 85 which couples the pump to the camera inlet port 81. With the free piston 82 in the extreme down position, the pump 80 is secured to the air inlet port 81 of the camera body 10. As the assembly is submerged, external water pressure forces the free piston 82 towards the camera body, forcing air into the pressure vessel to equalize the pressure between the camera and ambient external water pressure. As the assembly ascends, the ambient pressure around the assembly is less than the pressure within the camera body so the pressure in the camera body forces the free piston 82 back down the cylinder 83 of the pump 80. The pressure is equalized within the camera body as the camera descends or ascends by movement of free piston 32. In a preferred application of this embodiment, pump 80 is configured to function as a handle.
The free piston 82 is illustrated sectioned on a plane parallel to and passing through the vertical axis to illustrate the compression "O" ring 86, the stabalizing "O" ring 87, and inner ring pressure equalization bore 88.
To increase the operational depth of the assembly, a second pump 90 may be attached as a second hand hold for the camera. The second pump 90 functions identically to the first. It may be provided with an independent portal into the camera body 10 or connected via a T connector 96 to the basic camera inlet port 81.
The cylinders 83 and 93 may be fabricated from any suitable material such as brass or steel but preferably they are fabricated from a transparent plastic so the diver may use the scale 99 as an alternate depth gauge, determine if the piston seals are leaking and ascertain when the maximum equalization depth has been reached.
While preferred embodiments of this invention have been illustrated and described, variations and modifications may be apparent to those skilled in the art. Therefore, I do not wish to be limited thereto and ask that the scope and breadth of this invention be determined from the claims which follow rather than the above description.
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An apparatus and method for extending the depth range of an underwater pressure hull such as an underwater camera body by supplying gas to balance the internal hull pressure with the ambient water pressure. The balancing gas is supplied by a variable volume reservoir pneumatically connected to the pressure hull. The reservoir is reduced in volume by an increase in ambient water pressure to thereby increase the internal pressure of the system according to Boyle's Law. Conversely, a decrease in ambient water pressure results in an increase in the reservoir volume which reduces the internal hull pressure accordingly.
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FIELD OF THE INVENTION
This invention relates to a functional element commonly found in nearly all sewing machines, namely, a presser-foot. In particular, this invention relates to presser-foot apparatus which is self-adjustable for variable thicknesses and multiple layers of work.
BACKGROUND OF THE INVENTION
Apparatus which press against a workpiece that is to be sewn are generally known as presser-foot devices. These devices perform the function of preventing the material that is being sewn from lifting when the needle is being withdrawn from the workpiece. This tendency of the workpiece to lift with the needle will otherwise cause flagging and hence improper stitching.
Conventional presser-foot devices have for the most part been driven by various eccentric arrangements which move the presser-foot downwardly toward the workpiece in a timely fashion. This downward travel is usually limited to a pre-set height above the bed of the sewing machine. This pre-set height usually allows the presser-foot to move relatively close to a workpiece having a uniform thickness of one or more materials to be sewn. This close relationship of the presser-foot to the workpiece is maintained throughout the sewing period as long as the thickness does not vary appreciably.
Workpieces consisting of multiple layers of material usually present a problem for presser-feet having pre-set height limitations. A compromised setting must be used for sewing the different layers of these workpieces. Such a setting will result in the presser-foot making contact with the top layer of a two layer workpiece and substantially clearing the bottom layer. This compromised setting may or may not be sufficient to prevent flagging and hence improper stitching. The solution to this problem is often to lower the sewing speed which reduces the overall productivity of the machine. When the variable thickness of the workpiece exceeds two levels of thickness, a compromised setting is even less practical.
The problem encountered with sewing at various levels has been somewhat remedied by self-adjusting presser-foot devices. These devices are capable of adjusting to the different thicknesses of a workpiece so as to always maintain contact therewith. These devices vary as to their success in achieving a satisfactory pressurized contact. These devices are furthermore often complex and susceptible to extreme wear of their various parts. These complex mechanisms furthermore often dictate that the presser-foot must maintain a relationship relative to the needle which does not allow for an easy threading of the needle.
OBJECT OF THE INVENTION
It is an object of this invention to provide a new and improved presser-foot apparatus which allows multi-level work to be successfully stitched at high speeds.
It is another object of this invention to provide a new and improved presser-foot apparatus which produces substantially steady contact pressure with the work that is being sewn.
It is a still further object of this invention to provide a new and improved presser-foot apparatus which permits a normal threading of the needle.
It is an even further object of this invention to provide a presser-foot apparatus which adjusts to the level of work being sewn with a minimum amount of mechanical complexity.
SUMMARY OF THE INVENTION
The above and other objects are achieved according to the present invention by providing a spring biased presser-foot which is operatively coupled to a needle bar shaft. The spring biasing is accomplished by a helical spring fixed at one end to a stationary member that does not move relative to the reciprocating needle bar shaft. The opposite end of the helical spring is biased against a column extending above the presser-foot. The column is slidably supported within a housing that is affixed to the needle bar shaft. The presser-foot normally moves with the needle bar shaft in a downward manner until such time as contact is established with a workpiece. The needle bar shaft and the housing affixed thereto continue to travel downward while the presser-foot remains pressed against the workpiece. The pressure exerted by the presser-foot on the workpiece is maintained at a steady state value while the needle bar shaft completes its downward movement and again moves upward to a point wherein the needle is withdrawn from the workpiece. At this time, the housing affixed to the needle bar shaft catches the top of the column extending above the presser-foot and lifts the same off the workpiece.
In accordance with the invention, provision is also made for withdrawing the spring biased presser-foot to a position which allows for the threading of the needle. The normal position of the presser-foot relative to the sewing needle is established upon the next cycle of needle bar movement.
In accordance with yet another aspect of the present invention, an alternative embodiment is disclosed wherein the helical spring biasing is replaced by a pressurized air cylinder. The pressurized air cylinder forms the requisite spring action for the presser-foot.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other features of the present invention will now be particularly described with reference to the accompanying drawings, in which:
FIG. 1 is a perspective view of the presser-foot apparatus of the present invention;
FIG. 2 is a front view of a sewing machine incorporating the presser-foot apparatus of FIG. 1;
FIG. 3 illustrates an operative position of the presser-foot relative to a workpiece that is to be sewn;
FIG. 4 is an exploded view of certain parts of the presser-foot apparatus which allow the sewing needle to be threaded;
FIG. 5 illustrates the position of the presser-foot which allows for the threading of the sewing needle; and
FIG. 6 illustrates an alternative embodiment to the presser-foot apparatus of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, a presser-foot 10 is generally illustrated relative to a sewing needle 12. The needle 12 is connected to a needle bar 14 which is driven via a drive connection 16 in a conventional manner. The needle bar reciprocates within a stationary guide member 18 which is physically attached to the frame of a sewing machine that is only partially shown. The attachment is in the form of a screw 20 which secures the stationary guide member 18 to a portion of an upper-frame member 22. The lower portion of the guide member 18 is maintained in position by a blind pin 24 which extends into a portion of a lower-frame member 26 of the sewing machine. It is to be appreciated that the stationary guide member 18 could merely be part of the sewing machine frame itself without departing from the scope of the invention.
Referring again to the presser-foot 10, it is seen that the same is attached to a cylindrical shaft 28 which extends upwardly into a cylindrical housing 30. The housing 30 includes a support base 32 which attaches to the needle bar 14. This attachment allows the housing 30 to move up and down with the needle bar 14. It is to be noted that the shaft 28 extends completely through the cylindrical housing 30 and terminates in a top end 34. The top end 34 is separated from the housing 30 by a hard rubber ring 36.
Referring to FIG. 2, the presser-foot apparatus is illustrated within the front portion of a sewing head 46. The sewing head is part of a conventional sewing machine wherein the needle 12 is driven in a conventional manner. Specifically, an eccentric drive 48 located at the top of the sewing head 46 is operative to move a drive link 50 which in turn transmits vertical movement to the drive connection 16 located on the needle bar. This in turn causes the needle bar 14 to move in a normal fashion.
Provision is made within the sewing head 46 for accomodating the various parts of the presser-foot apparatus. In particular, this includes a spacial cavity 52 which accomodates the various parts of the presser-foot apparatus as shown. This includes the top member 44 which extends outwardly into the cavity 52 from the guide member 18. As has been previously discussed, the adjusting nut 40 and the threaded bolt 42 depend from the top member 44 so as to define a fixed top reference point for the helical spring 38. The helical spring 38 is maintained in a vertical position below this top reference point by a downwardly extending cylindrical member 54 which forms part of the lower threaded shaft 42. The downwardly extending cylindrical member 54 is sufficiently downstream of the threaded portion of the shaft 42 so as to allow for appropriate biasing adjustments by the adjustment nut 40. Referring now to the bottom portion of the presser-foot apparatus and in particular to the housing 30, it is seen that the same extends upwardly through an annular opening 56. The annular opening 56 allows the housing 30 to freely move up and down.
The overall operation of the presser-foot apparatus within the sewing head 46 will now be described in terms of an overall sewing cycle. In operation, the needle bar 14 is driven downwardly by the drive link 50 which is pivotally connected to both the drive connection 16 and the eccentric drive 48 of the sewing machine. This causes the cylindrical housing 30 to move downwardly by virtue of its base 32 being affixed to the needle bar 14. The helical spring 38 maintains the top end 34 of the shaft 28 against the hard rubber ring 36 which in turn presses against the cylindrical housing 30. This causes the presser-foot 10 to move downwardly with the cylindrical housing 30. This downward movement of the presser-foot 10 continues to occur until the toe of the presser-foot 10 contacts a workpiece 58. At this time, the presser-foot 10 and the shaft 28 extending thereabove ceases to move downwardly. On the other hand, the housing 30 continues to move downwardly with the needle bar 14. This produces relative downward movement of the housing 30 along the length of the shaft 28. This relative downward movement continues to occur as the needle 12 moves downwardly through the workpiece 58.
Referring to FIG. 3, the needle 12 is seen to have moved through the workpiece 58 and hence through a throat plate 60. The housing 30 connected to the needle bar 14 has moved down the shaft 28 as illustrated. This relative movement of the housing 30 has allowed the presser-foot 10 to maintain a steady pressure dictated by the non-varying length of the helical spring 38 after contact with the workpiece.
As illustrated in FIG. 3, the needle 12 has reached its furthest point of downward travel. The needle 12 now begins to move upwardly while the workpiece 58 is maintained against the throat 60 by virtue of the steady unvarying pressure exerted by the presser-foot 10. This continues to occur until the needle is actually withdrawn from the workpiece whereupon the housing 30 again makes contact with the shock absorbent ring 36 and begins to lift the presser-foot 10 off the workpiece. The workpiece 58 is now free to be repositioned for the next subsequent stitch which will take place during the next sewing cycle. The repositioned workpiece may in fact produce a different thickness of material to be sewn. This will merely result in a different level of contact being experienced by the presser-foot 10. The presser-foot 10 will again produce a steady downward pressure at this level while the needle proceeds through the workpiece.
As can be appreciated, the presser-foot 10 is normally maintained at the end of the needle 12 when the needle is not in the workpiece. This allows for an initial contact of the presser-foot with the workpiece prior to any needle penetration. Provision has however been made to withdraw the presser-foot 10 relative to the needle 12 so as to allow for the threading of the needle. Referring to FIG. 1, a cantilevered leaf-spring 62 is attached to the heel of the presser-foot 10. The leaf-spring 62 contains a keyhole 64 which will engage a pin 66 on the base 32. The pin 66 is not actually visible in FIG. 1, but can be readily seen in FIG. 4. FIG. 4 additionally illustrates the relative position of the leaf-spring 62 to both the heel of the presser-foot 10 as well as the rearward portion of the base 32. The leaf-spring 62 is seen to fit into a recess 68 within the heel of the presser-foot 10. The leaf-spring 62 extends upwardly into an opening between a pair of prongs 70 and 72 in the rearward portion of the base connection 32. The pin 66 is located between the prongs 70 and 72 as shown.
The manner in which the presser-foot 10 is repositioned relative to the needle will now be described. The presser-foot 10 is manually raised against the downward pressure exerted by the helical spring 38 until the circular hole of the keyhole 64 is opposite the pin 66. At this point, the leaf-spring 62 is physically pushed towards the base 32 so as to cause the circular hole to move over the head of the pin 66. The presser-foot 10 is now allowed to move slightly downward so as to allow the slot portion of the keyhole 64 to move down behind the head of the pin 66. At this point, the presser-foot 10 will be held above the end of the needle 12 so as to allow for threading. This is clearly shown in FIG. 5.
The presser-foot 10 will subsequently be returned to its normal position relative to the sewing needle during the next sewing cycle. Specifically, the presser-foot 10 will contact the workpiece on the next sewing cycle causing the leaf-spring 62 to no longer move with the cylindrical housing 30. At this time, the pin 66 will begin to move down the slot of the keyhole 64 until the head of the pin is in the circular hole portion. At this time, the leaf-spring 62 will spring loose so as to thereby move free of the pin 66.
It is to be noted that the position of the presser-foot 10 could also be repositioned relative to the end of the needle 12 by manually moving the presser-foot upwardly. The leaf-spring 62 would merely move away at such time as the circular hole portion of the keyhole 64 is opposite the head of the pin 66.
Referring again to FIG. 4, a guide 74 also fits into a second and larger recess 76 within the heel of the presser-foot 10. The width of the guide 74 is substantially the same as the distance between the prongs 70 and 72 of the rearward portion of the base connection 32. This allows for the guide 76 to freely move up and down between the prongs 70 and 72. This guiding of heel of the presser-foot 10 assures that the presser-foot will not rotate relative to the needle 12.
Referring now to FIG. 6, an alternative to the helical spring 38 of FIG. 1 is illustrated. In particular, the helical spring 38 has been replaced by a pressurized chamber. The pressurized chamber comprises a bottom vessel 80 which is physically attached to the base 32. An inner hollow cylinder 82 attaches to the top 34 of the shaft 28 and slidably engages the inner wall of the bottom vessel 80. The inner hollow cylinder 82 will normally be maintained at the extreme bottom of the pressurized chamber so as to thereby bias the hard rubber ring 36 against the base 32. The bottom vessel 80 will however move relative to the inner hollow cylinder 82 when relative movement occurs between the shaft 28 and the base 32. As has been previously discussed, this occurs upon contact of the presser-foot 10 with a workpiece. The pressurized chamber furthermore comprises a top vessel 84 which is affixed to the member 44. The outer wall of the top vessel 84 slidably engages the inner wall of the lower vessel 80. This allows for the relative movement of the lower vessel 80 with respect to the top vessel 84. This latter movement occurs as a result of the needle bar 14 moving relative to the needle bar guide 18. The top vessel 84 contains a pneumatic valve fitting 86 which provides for an appropriate pneumatic pressure to be built up in the pressurized chamber comprising the vessels 80 and 84. The thus built up pressure is such as to define an appropriate spring constant similar to that of the helical spring 38. This pressure will allow the presser-foot to produce the steady non-varying contact pressure on the workpiece after contact therewith.
The thus pressurized chamber can be easily depressurized by appropriate control of a valve upstream of the valve fitting 86. This would allow for a lessening of the spring constant experienced when manually moving the presser-foot upwardly so as to thread the needle. This would furthermore allow for adjustably defining the biasing pressure for various sewing conditions.
From the foregoing, it is to be appreciated that a preferred embodiment and an alternative thereto have been disclosed for a presser-foot apparatus. It is to be appreciated that alternative structure may be substituted for various elements of these embodiments without departing from the scope of the present invention.
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Presser-foot apparatus is disclosed which is capable of automatically adjusting to various levels of sewing. The presser-foot is slidably held within a housing affixed to a needle bar. The presser-foot is biased against the housing so as to move in conjunction therewith until contact is made with the workpiece. The presser-foot exerts a steady, unvarying pressure on the workpiece while the needle associated therewith continues downwardly. The presser-foot is ultimately lifted from the workpiece during the upward retraction of the needle from the workpiece.
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BACKGROUND INFORMATION
German Patent Application No. DE 100 32 022 describes a method for determining the activation voltage for a piezoelectric actuator of an injector, which provides for first measuring the pressure prevailing in a hydraulic coupler indirectly, prior to the next injection event. The pressure is measured in that the piezoelectric actuator is mechanically coupled to the hydraulic coupler, so that the pressure induces a corresponding voltage in the piezoelectric actuator. This induced voltage is used prior to the next injection event to correct the activation voltage, inter alia, for the actuator. An induced voltage that is too low is indicative of a missed injection. The injector is preferably used for injecting fuel for a gasoline or diesel engine, in particular for common-rail systems. In this context, the pressure prevailing in the hydraulic coupler also depends, inter alia, on the common-rail pressure, so that the activation voltage is varied as a function of the common-rail pressure. The voltage requirement of a piezoelectric actuator depends first and foremost on the pressure prevailing in the valve chamber, as well as on the coefficient of linear expansion of the piezoelectric actuator. The voltage required for properly operating the injector at one operating point is the so-called voltage requirement, i.e., the relationship between voltage and lift at a specific force which is proportional to the common-rail pressure.
German Patent No. DE 103 15 815.4 discusses deriving the active voltage requirement of an injector from the voltage difference between the maximum actuator voltage and the final steady-state voltage.
It is problematic in this regard, however, that the voltage requirement of an injector drifts over the service life of the injector. The effect of this drift is that the actuator voltage that is predefined as a function of one operating point does not ensure a proper operation of the injector at a predefined operating point. This leads to errors in the injection quantity which, in turn, cause negative exhaust-emission levels and negative noise emissions. In the least favorable case, a failure of the injection and thus of the injector may even occur, namely when the lift no longer suffices for opening an injection-nozzle needle.
Therefore, an object of the present invention is to compensate for this voltage requirement drift.
SUMMARY OF THE INVENTION
This objective is achieved by a method for determining the activation voltage of a piezoelectric actuator of an injector. The method according to the present invention makes it possible to compensate for the voltage requirement drift by adapting the setpoint voltage value, thereby ensuring that the required, nominal actuator excursion is attained and ensuring a proper and desired operation of the injector over the entire lifetime. In addition, by adapting the voltage requirement, the advantage is derived, in principle, that a very high voltage allowance is not needed for the activation, so that a considerable benefit is gained with respect to the power input/power loss. Moreover, the adaptation of the voltage requirement may also be used for diagnostic purposes, for example in order to output an error message in response to an unacceptably high drift of the voltage requirement.
The control of the voltage requirement drift is advantageously carried out during one driving cycle of a vehicle having the internal combustion engine, correction values ascertained during the driving cycle being stored in a non-volatile memory. This makes it feasible, in particular, for the correction values stored in the memory to be used in a later driving cycle, as initialization values for a further compensation of the voltage requirement drift.
To ensure that an adaptation is only carried out in response to an actual voltage requirement drift, i.e., that no readjustment is made in response to only temporary, relatively small deviations, caused, for example, by temperature effects, an enable logic is preferably provided, which enables an adaptation of the voltage requirement drift as a function of parameters characterizing the internal combustion engine and/or the injector.
These parameters include, for example, the temperature of the internal combustion engine and/or the common-rail pressure and/or the steady state of the voltage control and/or the state of the charging time control and/or the steady state of other secondary feedback control circuits and/or the number of injections and/or the control (activation) duration and/or the injection sequence per combustion cycle, i.e., effectively, the injection pattern (preinjection(s), main injection, post injection(s)).
The voltage requirement is compensated at various operating points very advantageously with respect to the common-rail pressure, the correction values being stored in correction characteristics maps, which are then also stored in the non-volatile memory, for example in an E 2 -PROM.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the schematic design of an injector known from the related art.
FIG. 2 schematically illustrates a graphic representation of the actuator voltage over time, during one activation.
FIG. 3 schematically shows a block diagram of a control system that utilizes the method according to the present invention.
DETAILED DESCRIPTION
FIG. 1 schematically depicts an injector 1 , known from the related art, having a central bore. In the upper part, an actuating piston 3 having a piezoelectric actuator 2 is introduced into the central bore, actuating piston 3 being fixedly coupled to actuator 2 . A hydraulic coupler 4 is upwardly delimited by actuating piston 3 , while in the downward direction, an opening having a connecting channel to a first seat 6 is provided, in which a piston 5 having a valve-closure member 12 is situated. Valve-closure member 12 is designed as a double-closing control valve. It closes first seat 6 when actuator 2 is in the rest phase. In response to actuation of actuator 2 , i.e., application of an activation voltage Ua to terminals +, −, actuator 2 actuates actuating piston 3 and, via hydraulic coupler 4 , presses piston 5 having closure member 12 toward a second seat 7 . Disposed in a corresponding channel, below the second seat, is a nozzle needle 11 , which closes or opens the outlet in a high-pressure channel (common-rail pressure) 13 , depending on which activation voltage Ua is applied. The high pressure is supplied by the medium to be injected, for example fuel for a combustion engine, via a supply channel 9 ; the inflow quantity of the medium in the direction of nozzle needle 11 and hydraulic coupler 4 is controlled via an inflow throttling orifice 8 and an outflow throttling orifice 10 . In this context, hydraulic coupler 4 has the task, on the one hand, of boosting the lift of piston 5 and, on the other hand, of uncoupling the control valve from the static temperature-related expansion of actuator 2 . The refilling of coupler 4 is not shown here.
The mode of operation of this injector is explained in greater detail in the following. In response to each activation of actuator 2 , actuating piston 3 is moved in the direction of hydraulic coupler 4 . Piston 5 having closure member 12 , moves toward second seat 7 . In the process, a portion of the medium, for example of the fuel, contained in hydraulic coupler 4 is forced out via leakage gaps. For that reason, hydraulic coupler 4 must be refilled between two injections, in order to maintain its operational reliability.
A high pressure, which in the case of the common-rail system may amount to between 200 and 2000 bar, for example, prevails across supply channel 9 . This pressure acts against nozzle needle 11 and keeps it closed, preventing any fuel from escaping. If actuator 2 is actuated at this point in response to activation voltage Ua and, consequently, closure member 12 moved toward the second seat, then the pressure prevailing in the high-pressure region diminishes, and nozzle needle 11 releases the injection channel. P 1 denotes the so-called coupler pressure, as is measured in hydraulic coupler 4 . A steady-state pressure P 1 , which, for example, is 1/10 of the pressure prevailing in the high-pressure portion, ensues in coupler 4 , without activation Ua. Following the discharging of actuator 2 , coupler pressure P 1 is approximately 0 and is raised again in response to refilling.
At this point, the lift and the force of actuator 2 correlate with the voltage used for charging actuator 2 . Since the force is proportional to the common-rail pressure, the voltage for a required actuator excursion must be adapted as a function of the common-rail pressure to ensure that seat 7 is reliably reached. The voltage required for properly operating the injector or injector 1 at one operating point is the so-called voltage requirement, i.e., the relationship between voltage and lift at a specific force which is proportional to the common-rail pressure. German Patent No. DE 103 15 815.4 discusses how the individual, active voltage requirement of an injector can be derived from the voltage difference between the maximum actuator voltage and the final steady-state voltage.
This voltage requirement drifts over the lifetime of injector 1 . The effect of this drift is that the actuator voltage that is predefined as a function of one operating point no longer ensures a proper operation of injector 1 at the specified operating point, which leads to errors in the injection quantity, thereby entailing consequences for exhaust-emission levels/noise emissions, culminating in a failure of the injector, namely when the lift no longer suffices for opening nozzle needle 11 . The method described in the following makes it possible to compensate for this voltage requirement drift on an injector-specific basis.
An idea underlying the present invention is to compensate for the voltage requirement drift by adapting the setpoint voltage value, thereby ensuring that the required, nominal actuator excursion is attained and enabling the proper and desired operation of injector 1 to be ensured over its entire lifetime. Thus, on the one hand, the functioning of actuator 2 is ensured, but on the other hand the injection quantity errors described above are also avoided.
In principle, by adapting the voltage requirement in this manner, the need is also eliminated for activation processes that require a very high voltage allowance. This is advantageous, in particular, with respect to the power input/power loss of a control system. Moreover, actuator 2 is subject to less wear, since there is no need for actuator 2 to be operated over an entire lifetime with a very large voltage allowance, which is associated with too high of a power surplus in the valve seat.
Moreover, by monitoring the correction intervention of the adaptation, a diagnostic may also be performed on the entire injector, for example when an unacceptably high drift of the voltage requirement is ascertained.
The adaptation of the voltage requirement drift is based on automatically controlling the voltage difference between cutoff-voltage threshold U cutoff and the measured, final steady-state voltage U control (compare FIG. 2 ), in an injector-specific manner, to a setpoint value ΔU setpoint which is required for one operating point and which correlates with the required actuator excursion of an injector that has not drifted, i.e., that is performing nominally. This control intervenes correctively by adapting the setpoint actuator voltage in an injector-specific manner, as is described in greater detail below in conjunction with FIG. 3 .
An actuator setpoint voltage U setpoint is calculated in an arithmetic logic unit 310 . During the driving cycle, difference ΔU actual between cutoff voltage U cutoff and control voltage U control is continually determined. This difference ΔU actual is compared to a predefined quantity ΔU setpoint , the difference between quantity ΔU setpoint and ΔU actual being determined in a node 320 . This difference e ΔU forms the input quantity for a PI controller, for example, in which various controllers 331 , 332 , 33 n are provided for each of the individual cylinders. In these controllers, cylinder-specific correction signals S 1 , S 2 , S n are defined in each instance and output, n describing the number of cylinders.
The correction values are either multiplied by setpoint voltage U setpoint determined in arithmetic logic unit 310 or, alternatively, added to it, as indicated by nodes 341 , 342 . The thus ascertained corrected values U setpointcorr are fed to an actuator-voltage control device 350 , which determines cutoff-voltage threshold U cutoff . At this point, this cutoff-voltage threshold U cutoff is utilized, together with the ensuing final steady-state voltage U control , in turn, to determine difference ΔU actual .
Correction values S 1 , S 2 , . . . S n learned during one driving cycle are preferably stored following termination of the driving cycle in a non-volatile memory 360 , for example in an E 2 -PROM, and used before the beginning of the subsequent driving cycle as initialization values for the further adaptation, as schematically depicted in FIG. 3 by an arrow 362 denoted by “INIT”. It is noted at this point that, to calculate voltage difference ΔU actual for the method described above, maximum voltage U max (compare FIG. 2 ) cannot be used, as described in German Patent No. DE 103 15 815.4, but rather cutoff-voltage threshold U cutoff , since U max is not available as a usable quantity in a generally known engine control unit, in which this control is also executed. The voltage requirement drift is also compensated, however, when the cutoff voltage U cutoff quantity is used.
To ensure that the adaptation is only carried out in response to an actually existing voltage requirement drift, i.e., that controllers 331 , 332 , 33 n only control in this case and not, for instance, in response to temporary, relatively small deviations, caused, for example, by temperature effects, by the dynamic operation, etc., an enable logic circuit is provided in a circuit unit 370 , which monitors typical parameters for enabling the adaptation. These parameters of the internal combustion engine and/or of the injector include, for example, the temperature of the internal combustion engine and/or the common-rail pressure and/or the steady state of the voltage control and/or the state of the charging time control and/or the steady state of other secondary feedback control circuits and/or the number of injections and/or the control (activation) duration and/or the injection sequence per combustion cycle, i.e., effectively, the injection pattern (preinjection(s), main injection, post injection(s)). A steady state of the voltage control is verified, for example, by comparing quantities U setpointcorr and U control . Only if U setpointcorr and U control conform, are PI controllers 331 , 332 . . . 33 n enabled by circuit unit 370 , so that difference ΔU actual may be adapted to ΔU setpoint , as described above, thereby making it possible for the voltage requirement drift to be adapted.
If, on the other hand, the test reveals that the actuator voltage control is not steady-state, thus, when U setpointcorr deviates from U control , PI controllers 331 , 332 , . . . 33 n are deactivated by enable-logic circuit unit 370 , and correction values S 1 , S 2 , . . . S n remain unchanged, i.e., are, to a certain extent, frozen. The setpoint voltage value continues to be corrected at switching points 341 / 342 using values S 1 , S 2 , . . . S n learned up to that point. Such a “freezing” of the correction values is possible since the injector drift occurs very slowly.
The method described above may initially be carried out only at one operating point (common-rail pressure), and the acquired correction values used for all operating points. To enhance the accuracy, the method may also be carried out at a plurality of different operating points (common-rail pressures).
Moreover, it should be pointed out that the comparison of an injector-specific correction value S 1 , S 2 , . . . S 3 , which represents a measure of the deviation of the voltage requirement from the standard, to a predefinable threshold value, may additionally be used for diagnostic purposes. In this manner, it is possible to diagnose the system including actuator 2 , coupler 4 , and the control valve, which is constituted of valve-closure member 12 .
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A method for determining the activation voltage of a piezoelectric actuator of at least one injector which is used to inject a liquid volume under high pressure into a cavity, in particular into a combustion chamber of an internal combustion engine, the activation voltage being varied as a function of the pressure used to pressurize the liquid volume. A drift of the activation voltage (voltage requirement) required for a predefined lift of a control valve of the injector is controlled on an injector-specific basis by controlling the difference between the cutoff-voltage threshold and the final steady-state voltage to a setpoint value predefined for one operating point.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] This is a continuing application of application Ser. No. 09/939,166, filed on Aug. 24, 2001; this application also claims the priority of copending international application No. PCT/US2002/027070, filed Aug. 23, 2002, which designated the United States; the prior applications are herewith incorporated by reference in their entirety.
FIELD OF THE INVENTION
[0002] This invention relates generally to tissue treatment systems. More particularly this invention relates to vacuum assisted treatment systems that aid in the healing of open wounds.
BACKGROUND OF THE INVENTION
[0003] Vacuum induced healing of open wounds has recently been popularized by Kinetic Concepts, Inc. of San Antonio, Tex., by its commercially available V.A.C.® product line. The vacuum induced healing process has been described in commonly assigned U.S. Pat. No. 4,969,880 issued on Nov. 13, 1990 to Zamierowski, as well as its continuations and continuations in part, U.S. Pat. No. 5,100,396, issued on Mar. 31 1992, U.S. Pat. No. 5,261,893, issued Nov. 16, 1993, and U.S. Pat. No. 5,527,293, issued Jun. 18, 1996, the disclosures of which are incorporated herein by this reference. Further improvements and modifications of the vacuum induced healing process are also described in U.S. Pat. No. 6,071,267, issued on Jun. 6, 2000 to Zamierowski and U.S. Pat. Nos. 5,636,643 and 5,645,081 issued to Argenta et al. on Jun. 10, 1997 and Jul. 8, 1997 respectively, the disclosures of which are incorporated by reference as though fully set forth herein. Additional improvements have also been described in U.S. Pat. No. 6,142,982, issued on May 13, 1998 to Hunt, et al.
[0004] In practice, the application to a wound of negative gauge pressure, commercialized by Assignee or its parent under the designation “Vacuum Assisted Closure” (or “V.A.C.®”) therapy, typically involves the mechanical-like contraction of the wound with simultaneous removal of excess fluid. In this manner, V.A.C.® therapy augments the body's natural inflammatory process while alleviating many of the known intrinsic side effects, such as the production of edema caused by increased blood flow absent the necessary vascular structure for proper venous return. As a result, V.A.C.® therapy has been highly successful in the promotion of wound closure, healing many wounds previously thought largely untreatable.
[0005] The frequency at which negative pressure is applied to the wound, as well as the frequency of the pressure change over time, has a direct impact on the rate of wound healing. A variation of pressure change over time, not provided by current vacuum assisted therapy devices, is thought to significantly increase the rate of wound healing. Similarly, a rapid return to normal activities for the patient receiving wound therapy, may also improve the rate of wound healing, as increased physical activity is often accompanied by increased vascular circulation, which in turn leads to improved blood flow at the wound site. One barrier to a return to normal activities is limited battery life, which is a result of the electrical power required to power existing vacuum assisted wound therapy systems. Additionally, frequent inspection of the wound site is required in order to ensure the wound is not becoming infected. However, a rapid return to normal activities must not preclude the precautions that must be utilized during use of vacuum assisted therapy to prevent inadvertent spillage of wound exudates from the canister, or entry of wound exudates into the pumping mechanism.
[0006] Additional limitations are associated with the use of fixed frequency oscillating pumps in the prior art. Such limitations are the result of the size of the pump required to maintain the desired negative pressure at the wound site, and/or a reduction in battery life due to the power required to operate the oscillating pumps. Oscillating pumps, as known in the art, are typically designed for limited operating conditions. For example, to maximize low pressure flow rate at a fixed frequency. Typically the mass and/or stiffness of various components are altered to change the resonant frequency of the pump under the design operating conditions. If the pressure across the pump increases, the stiffness of the system is increased by back pressure across the diaphragm of the oscillating pump. The resonant frequency of the pump changes and the fixed frequency drive is not driving the pump at the optimum frequency. As a result, flow rate drops quickly and the capability of the pump to drive air at high pressure is limited. Accordingly, in order to provide increased flow rate at higher pressures requires either a sacrifice in flow rate at low pressures, or a pump of significantly greater size, when utilizing a fixed frequency oscillating pump.
[0007] For the foregoing reasons, there is a need for a vacuum assisted wound treatment system that is capable of automated pressure change over time. Additionally, there is a need for a more efficient vacuum assisted wound treatment system, that allows the patient more mobility, while reducing the risk of exudate spillage or pump contamination.
[0008] It is therefore an object of the present invention to provide a vacuum assisted wound treatment system that provides a means for increasing the stimulation of cellular growth by a variation of pressure over time.
[0009] A further object is to provide a system that is capable of extended operation in the absence of an alternating current power supply.
[0010] An additional object of the present invention is to provide a sanitary and cost effective means for sampling fluids drawn from the wound site without necessitating removal of the canister, or disturbing of the wound site.
[0011] Still another object of the present invention is to provide a vacuum assisted wound therapy device that can be secured to an object so as to reduce the likelihood of disturbance to the device, while still allowing convenient placement for its operation.
SUMMARY OF THE INVENTION
[0012] In accordance with the foregoing objects, the present invention generally comprises a porous pad for insertion substantially into a wound site and a wound drape for air-tight sealing enclosure of the pad at the wound site. A distal end of a tube is connected to the dressing in order to provide negative pressure at the wound site. A fluid sampling port is provided on the tube to allow for sampling of wound fluids being drawn through the tube from the wound site. A source of negative pressure is in communication with a proximal end of the tube. A collection canister is removably connected to the tube for collection of fluid removed from the wound during the application of negative pressure. A first filter is incorporated into an opening of the canister, and a second filter is positioned between the canister and the source of negative pressure. As the source of negative pressure may be an electric pump, supplied by alternating or direct current, a power management device, and its associated power management protocol, is incorporated to maximize battery life when the unit is being supplied by direct current. A clamping mechanism is utilized to secure the system to a stationary object, such as a bed rail, or pole, such as that used to suspend a container of intravenous fluid.
[0013] The pad, comprised of a foam having relatively few open cells in contact with the areas upon which cell growth is to be encouraged so as to avoid unwanted adhesions, but having sufficiently numerous open cells so that drainage and negative pressure therapy may continue unimpaired, is placed in fluid communication with a vacuum source for promotion of fluid drainage, as known in the art. The porous pad of the present invention may be comprised of polyvinyl alcohol foam. The fluid communication may be established by connecting a tube to a dressing, such as that described in International Application WO 99/13793, entitled “Surgical Drape and Suction Heads for Wound Treatment,” the disclosure of which is incorporated herein.
[0014] Upon placement of the pad, an airtight seal is formed over the wound site to prevent vacuum leakage. Such a seal may be provided by placing a drape over the wound, such that the drape adheres to the healthy skin surrounding the wound site, while maintaining an airtight seal over the wound itself.
[0015] A conduit or tube is placed in fluid communication with the foam pad, its distal end communicating with a fluid drainage canister which is in fluid communication with a vacuum source. A constant or intermitant negative pressure therapy is conducted as described in the prior art. Alternatively, the negative pressure is varied over time, so as to further stimulate cell growth, which in turn may shorten the healing process. The negative pressure induced on the wound adjusts to meet a varying target pressure, which oscillates between a target maximum and target minimum pressure.
[0016] Flow rate of a variable displacement pump, used in accordance with the present invention, is maximized over a pressure range by varying the drive frequency of the pump. The optimum drive frequency is continuously adjusted by a system that periodically or continuously monitors the pressure across the pump to determine the optimum drive frequency for that pressure. Pump performance is thereby improved over variable displacement pumps utilized in the prior art, without increasing pump size or weight. Similarly, pump performance of a typical variable displacement pump can be achieved with a smaller pump, which in turn reduces the size and weight of the overall system in order to improve ease of use and portability for the patient. An alternative negative pressure source, such as a fixed displacement pump, sometimes referred to as a positive displacement pump, may also be utilized.
[0017] The power management system is utilized to maximize battery life when the present invention is being supplied with electric power under direct current. The power management system comprises deactivation of a backlight to a display terminal, or touch screen liquid crystal display (LCD) control panel, after a predetermined interval. Battery life is further extended when the power management system prevents electric power from reaching an electric motor until the targeted power setting is actually large enough to activate the motor. In such an instance, the motor is utilized to provide negative pressure by driving an electric pump as known in the art.
[0018] The foregoing has outlined some of the more pertinent objects of the present invention. These objects should be construed to be merely illustrative of some of the more prominent features and applications of the invention. Many other beneficial results can be attained by applying the disclosed invention in a different manner or by modifying the invention as will be described. Accordingly, other objects and a fuller understanding of the invention may be had by referring to the following Detailed Description of the Invention, which includes the preferred embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] These and other features and advantages of the invention will now be described with reference to the drawings of certain preferred embodiments, which are intended to illustrate and not to limit the invention, and wherein like reference numbers refer to like components, and in which:
[0020] FIG. 1 is a schematic block diagram of a tissue treatment system utilized in accordance with the present invention.
[0021] FIG. 2A is a perspective view of a fluid sampling port utilized in accordance with the present invention.
[0022] FIG. 2B is a perspective view of an alternative embodiment of a fluid sampling port utilized in accordance with the present invention.
[0023] FIG. 3A is a perspective view of the back portion of a pump housing utilized in accordance with the present invention.
[0024] FIG. 3B is a perspective view of the front portion of a pump housing utilized in accordance with the present invention.
[0025] FIGS. 4A and 4B are flow charts representing the preferred steps in the implementation of a power management system utilized in accordance with the present invention.
[0026] FIG. 5 is a flow chart illustrating the preferred steps in the implementation of pulse therapy utilized in accordance with the present invention.
DESCRIPTION
[0027] Although those of ordinary skill in the art will readily recognize many alternative embodiments, especially in light of the illustrations provided herein, this detailed description is exemplary of the preferred embodiment of the present invention, the scope of which is limited only by the claims that are drawn hereto.
[0028] The present invention is a vacuum assisted system for stimulating the healing of tissue.
[0029] Referring now to FIG. 1 in particular, there is illustrated the primary components of a system that operates in accordance with the present invention. The present invention 10 includes a foam pad 11 for insertion substantially into a wound site 12 and a wound drape 13 for sealing enclosure of the foam pad 11 at the wound site 12 . The foam pad 11 may be comprised of a polyvinyl alcohol (PVA) open cell polymer material, or other similar material having a pore size sufficient to facilitate wound healing. A pore density of greater than 38 pores per linear inch is preferable. A pore density of between 40 pores per linear inch and 50 pores per linear inch is more preferable. A pore density of 45 pores per linear inch is most preferable. Such a pore density translates to a pore size of approximately 400 microns.
[0030] Addition of an indicating agent, such as crystal violet, methylene blue, or similar agents known in the art causes a color change in the foam 11 when in the presence of a bacterial agent. As such, a user or health care provider can easily and readily ascertain if an infection is present at the wound site 12 . It is contemplated that the indicating agent may also be placed in line of the conduit 16 , between the wound site 12 and the canister 18 . In such a configuration (not shown), the presence of bacterial contaminants in the wound site 12 , could be easily and readily ascertained without disturbing the wound bed, as there would be a nearly immediate color change as bacterially infected wound exudates are drawn from the wound site 12 and through the conduit 16 during application of negative pressure.
[0031] It is also contemplated that the foam pad 11 may be coated with a bacteriostatic agent. Addition of such an agent, would serve to limit or reduce the bacterial density present at the wound site 12 . The agent may be coated or bonded to the foam pad 11 prior to insertion in the wound site, such as during a sterile packaging process. Alternatively, the agent may be injected into the foam pad 11 after insertion in the wound site 12 .
[0032] After insertion into the wound site 12 and sealing with the wound drape 13 , the foam pad 11 is placed in fluid communication with a vacuum source 14 for promotion of fluid drainage and wound healing, as known to those of ordinary skill in the art. The vacuum source 14 may be a portable electrically powered pump, or wall suction as commonly provided in medical care facilities.
[0033] According to the preferred embodiment of the present invention, the foam pad 11 , wound drape 13 , and vacuum source 14 are implemented as known in the prior art, with the exception of those modifications detailed further herein.
[0034] The foam pad 11 preferably comprises a highly reticulated, open-cell polyurethane or polyether foam for effective permeability of wound fluids while under suction. The pad 11 is preferably placed in fluid communication, via a plastic or like material conduit 16 , with a canister 18 and a vacuum source 14 . A first hydrophobic membrane filter 20 is interposed between the canister 18 and the vacuum source 14 , in order to prevent wound exudates from contaminating the vacuum source 14 . The first filter 20 may also serve as a fill-sensor for canister 18 . As fluid contacts the first filter 20 , a signal is sent to the vacuum source 14 , causing it to shut down. The wound drape 13 preferably comprises an elastomeric material at least peripherally covered with a pressure sensitive adhesive for sealing application over the wound site 12 , such that a vacuum seal is maintained over the wound site 12 . The conduit 16 may be placed in fluidic communication with the foam 11 by means of an appendage 17 that can be adhered to the drape 13 .
[0035] According to the preferred method of the present invention, a second hydrophobic filter 22 is interposed between the first filter 20 and the vacuum source 14 . The addition of the second filter 22 is advantageous when the first filter 20 is also used as a fill sensor for the canister 18 . In such a situation, the first filter 20 may act as a fill sensor, while the second filter 22 further inhibits contamination of wound exudates into the vacuum source 14 . This separation of functions into a safety device and a control (or limiting) device, allows for each device to be independently engineered. An odor vapor filter 23 , which may be a charcoal filter, may be interposed between the first filter 20 and the second filter 22 , in order to counteract the production of malodorous vapors present in the wound exudates. In an alternate embodiment (not shown), the odor vapor filter 23 may be interposed between the second hydrophobic filter 23 and the vacuum source 14 . A second odor filter 15 may be interposed between the vacuum source 14 and an external exhaust port 25 , in order to further reduce the escape of malodorous vapors from the present system. A further embodiment allows for first 20 and second filters 22 to be incorporated as an integral part of the canister 18 to ensure that the filters 20 , 22 , at least one of which are likely to become contaminated during normal use, are automatically disposed of in order to reduce the exposure of the system to any contaminants that may be trapped by the filters 20 and 22 .
[0036] A means for sampling fluids may also be utilized by providing a resealable access port 24 from the conduit 16 . The port 24 is positioned between the distal end 16 a of the conduit 16 and the proximal end 16 b of the conduit 16 . The port 24 , as further detailed in FIGS. 2 a and 2 b , is utilized to allow for sampling of fluids being suctioned from the wound site 12 . Although the port 24 is shown as an appendage protruding from the conduit 16 , it is to be understood that a flush mounted port (not shown) will serve an equivalent purpose. The port 24 includes a resealable membrane 26 that after being punctured, such as by a hypodermic needle, the seal is maintained. Various rubber-like materials known in the art for maintaining a seal after puncture can be utilized.
[0037] The process by which wound fluids are sampled, utilizing the present invention, comprises penetrating the membrane 26 with a fluid sampler 28 , such as a hypodermic needle or syringe. The sampler 28 is inserted through the membrane 26 and into the port 24 until it is in contact with wound fluids flowing through the inner lumen 30 of the conduit 16 . As illustrated in FIG. 2 b , and further described in U.S. Pat. No. 6,142,982, issued to Hunt, et al. on May 13, 1998, and whose reference is incorporated herein as though fully set forth, the inner lumen 30 may be surrounded by one or more outer lumens 31 . The outer lumens 31 may serve as pressure detection conduits for sensing variations in pressure at the wound site 12 . In an alternative embodiment (not shown), the outer lumen or lumens 31 may act as the negative pressure conduit, while the inner lumen 30 may act as the pressure detection conduit. In the present invention, the fluid sampling port 24 , communicates only with the inner lumen 30 , so as not to interfere with pressure detection that may be conducted by the outer lumens 31 . In an alternate embodiment (not shown) in which the outer lumen 31 serves as the negative pressure conduit, the fluid sampling port 24 communicates with the outer lumen 31 .
[0038] The vacuum source 14 may consist of a portable pump housed within a housing 32 , as illustrated in FIGS. 3 a and 3 b . A handle 33 may be formed or attached to the housing 32 to allow a user to easily grasp and move the housing 32 .
[0039] According to the preferred embodiment of the present invention, a means for securing the housing 32 to a stationary object, such as an intravenous fluid support pole for example, is provided in the form of a clamp 34 . The clamp 34 , which may be a G-clamp as known in the art, is retractable, such that when not in use is in a stored position within a recess 36 of the housing 32 . A hinging mechanism 38 is provided to allow the clamp 34 to extend outward from the housing 32 , to up to a 90 degree angle from its stored position. An alternative embodiment (not shown) allows the clamp 34 to be positioned at up to a 180 degree angle from its stored position. The hinging mechanism 38 is such that when the clamp 34 is fully extended, it is locked in position, such that the housing 32 is suspended by the clamp 34 . A securing device 40 , such as a threaded bolt, penetrates through an aperture 42 of the clamp 34 , to allow the clamp 34 to be adjustably secured to various stationary objects of varying thickness.
[0040] Alternatively, the securing device 40 , may be comprised of a spring actuated bolt or pin, that is capable of automatically adjusting to various objects, such as intravenous fluid support poles, having varying cross-sectional thicknesses.
[0041] The present invention also allows for management of a power supply to the vacuum source 14 , in order to maximize battery life when the present invention is utilizing a direct current as its power supply. In the preferred embodiment, as illustrated in the flow chart of FIG. 4 a , a motor control 44 determines if the actual pressure is less than or equal to a target pressure 46 . If the actual pressure is less than the target pressure, a tentative motor drive power required to reach the target pressure is calculated 48 . If the tentative motor drive power required to reach the target pressure is greater or equal to the stall power 49 , the tentative motor drive power is actually applied to the motor 50 . If the actual pressure is greater than the target pressure, the tentative motor drive power is decreased and a determination is made as to whether additional power is needed to overcome the stall power 52 . If it is determined that the tentative power is inadequate to overcome the stall power, the tentative power is not supplied to the motor 54 . If the tentative power is adequate to overcome the stall power, the tentative power is actually applied to the motor 50 . The motor control 44 functions as a closed loop system, such that the actual pressure is continuously measured against the predetermined target pressure. The advantage of such a system is that it prevents power from being supplied to the motor when it is not necessary to maintain the target pressure specified for V.A.C therapy. Accordingly, battery life is extended because power is not needlessly used to power the motor when it is not necessary.
[0042] Battery life is further extended, as illustrated in the flow chart shown in FIG. 4 b , by providing a means, such as an integrated software program in a computer processor, for automatically disengaging a backlight of the visual display 19 of the present invention 10 (as seen in FIG. 3 b ). User input of information 55 , such as target pressure desired, or duration of therapy, activates 57 a backlight of the visual display 19 shown in FIG. 3 b . User input 55 may also be simply touching the visual display 19 , which may be a touch activated or a pressure sensitive screen as known in the art. Activation of an alarm 55 may also activate 57 the backlight of the display 19 . An alarm may be automatically activated if an air leak is detected at the wound site 12 . Such a leak may be indicated by a drop or reduction in pressure being detected at the wound site 12 . The backlight remains active until a determination is made as to whether a preset time interval has elapsed 58 . If the time interval has not elapsed, the backlight remains active 57 . If the time interval has elapsed, the backlight is automatically extinguished 59 , until such time as the user inputs additional information, or an alarm is sounded 55 .
[0043] Referring now back to FIG. 1 , battery life is further extended by means of a variable frequency pump drive system 80 , when the pump 14 , used in accordance with the present invention, is an oscillating pump. The pump drive system 80 consists of a pressure sensor 82 , a control system 84 , and a variable frequency drive circuit 86 . In the preferred embodiment the pressure sensor 82 measures the pressure across the pump, which is relayed to the control system 84 . The control system 84 determines the optimum drive frequency for the pump 14 given the pressure measured and relayed by the pressure sensor 82 . The optimum drive frequency for the pump 14 may be determined by the control system 84 either repeatedly or continuously. The control system 84 adjusts the variable frequency drive circuit 86 to drive the pump at the optimum frequency determined by the control system 84 .
[0044] The use of the variable frequency pump drive system 80 allows the pressure of the pump 14 to be maximized. In tests on sample oscillating pumps, the maximum pressure achieved was doubled by varying the drive frequency by only 30%. Additionally, the system 80 maximizes flow rate over the extended frequency range. As a result, performance of the pump 14 is significantly improved over existing fixed frequency drive system pumps without increasing the pump size or weight. Consequently, battery life is further extended, thus giving the user greater mobility by not having to be tethered to a stationary power source. Alternatively, a similar performance level to the prior art fixed frequency drive system pumps can be achieved with a smaller pump. As a result, patient mobility is improved by improving the portability of the unit.
[0045] The preferred embodiment also increases the stimulation of cellular growth by oscillating the pressure over time, as illustrated in the flow chart of FIG. 5 . Such an oscillation of pressure is accomplished through a series of algorithms of a software program, utilized in conjunction with a computer processing unit for controlling the function of the vacuum source or pump. The program is initialized when a user, such as a health care provider, activates the pulsing mode of the pump 60 . The user then sets a target pressure maximum peak value and a target pressure minimum peak value 62 . The software then initializes the pressure direction to “increasing” 63 . The software then enters a software control loop. In this control loop, the software first determines if the pressure is increasing 64 .
[0046] If the actual pressure is increasing in test 64 , a determination is then made as to whether a variable target pressure is still less than the maximum target pressure 70 . If the variable target pressure is still less than the maximum target pressure the software next determines whether the actual pressure has equaled (risen to) the ascending target pressure 66 . If the actual pressure has attained the ascending target pressure, the software increments the variable target pressure by one interval 68 . Otherwise, it refrains from doing so until the actual pressure has equaled the ascending target pressure. If the variable target pressure has reached the maximum target pressure in the test of block 70 the software sets the pressure direction to “decreasing” 69 and the variable target pressure begins to move into the downward part of its oscillatory cycle.
[0047] The interval may be measured in mmHg or any other common unit of pressure measurement. The magnitude of the interval is preferably in the range of about 1 to 10 mmHg, according to the preference of the user.
[0048] If the actual pressure is decreasing in test 64 , a determination is then made as to whether the variable target pressure is still greater than the minimum target pressure 74 . If the variable target pressure is still greater than the minimum target pressure the software next determines whether the actual pressure has attained (fallen to) the descending target pressure 76 . If the actual pressure has equaled the descending target pressure the software decrements the variable target pressure by one interval 72 . Otherwise it refrains from doing so until the actual pressure has equaled the descending target pressure. If the variable target pressure has reached the minimum target pressure in the test of block 74 , the software sets the pressure direction to “increasing” 73 and the variable target pressure begins to move into the upward part of its oscillatory cycle. This oscillatory process continues until the user de-selects the pulsing mode.
[0049] While the invention has been described herein with reference to certain preferred embodiments, these embodiments have been presented by way of example only, and not to limit the scope of the invention. Accordingly, the scope of the invention should be identified only in accordance with the claims that follow.
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A system for stimulating the healing of tissue comprises a porous pad positioned within a wound cavity, and an airtight dressing secured over the pad, so as to provide an airtight seal to the wound cavity. A proximal end of a conduit is connectable to the dressing. A distal end of the conduit is connectable to a negative pressure source, which may be an electric pump housed within a portable housing, or wall suction. A canister is positioned along the conduit to retain exudates suctioned from the wound site during the application of negative pressure. A first hydrophobic filter is positioned at an opening of the canister to detect a canister full condition. A second hydrophobic filter is positioned between the first filter and the negative pressure source to prevent contamination of the non-disposable portion of the system by exudates being drawn from the wound. An odor filter is positioned between the between the first and second hydrophobic filters to aid in the reduction of malodorous vapors. A securing means is supplied to allow the portable housing to be secured to a stationary object, such as a bed rail or intravenous fluid support pole. A means for automated oscillation of pressure over time is provided to further enhance and stimulate the healing of an open wound. A means for varying pump drive frequency and a means for managing a portable power supply are provided to increase battery life and improve patient mobility.
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FIELD OF THE INVENTION
[0001] The invention relates to security documents and their manufacturing methods, and relates in particular to security documents comprising an optical security component.
DESCRIPTION OF THE PRIOR ART
[0002] Generally, security documents, such as official identity documents, are made in two stages: first personalization data, such as the holder's personal data, are printed on the security document support, generally comprising paper, and these data are protected and secured by simultaneous transfer of various protective layers. The combination of the protective layers and the security document support is performed, according to the prior art, by thermal lamination or hot pressing of the security document so as to thermobind the protective layers on the security document support through, for example, a heat-reactivable adhesive.
[0003] The personalization data can include information to be read, or readable information, which usually appear as a photo and text in a visual inspection zone and in a zone readable by a machine.
[0004] To guard against counterfeiting or falsification of security documents and to increase the security level of these documents, it is known to incorporate therein particular security elements.
[0005] In said security documents, the security elements commonly used are optical security elements. These optical security elements are generally optically variable elements, such as diffractive structures including holograms. These optically variable elements are generally in the form of laminates which comprise a reflecting layer, at least partially transparent, and a layer comprising a diffractive microstructure and which are arranged so as to cover the variable data contained in security documents in order to protect these documents, particularly against the falsification of their data. These laminates have a dual function, one of authentication of the security document and one of protection of the security document against falsification. The optical security elements must be complex enough to prevent a counterfeiter from replicating or simulating the optical security element. The thickness of the layers transferred on the laminate is less than 10 microns (preferably less than 5 microns) which does not any confer rigidity to the assembly, which is therefore not handleable.
[0006] Attempts of falsification, counterfeiting, or violation of security documents protected by a laminate consist mostly in sticking an adhesive film on the laminate and then peeling the entire film/laminate from the security document following the dissolution with a solvent or the reactivation by heating of the adhesive, which keeps the laminate stuck on the document. The falsifier has then the possibility to peel the laminate from the security document without damaging either the security document, or the personalization data that it holds, or, above all, the laminate. The falsifier can then, for example, falsify the personalization data of the security document and then stick back the laminate over it or stick the laminate on another security document.
[0007] It is known, to prevent this falsification attack, to incorporate into the security documents reagents intended to cause a coloured reaction in the event of attack of the security document with solvents, among others non-polar solvents.
[0008] WO-A-00/71361 discloses a process of protecting an object in which a thin protective film of synthetic material is stuck on one side of the object with an adhesive layer inserted between said side and the object, characterized in that at least one printing is inserted between the film and said side of the object, the at least one printing being made with an ink composition comprising at least a pigment and a binder hardenable by drying in air, adapted to form a solid printing layer after drying, and incorporating at least one agent, known as a soluble agent, adapted to dissolve in any polar and/or non-polar liquid solvent suitable for enabling the peeling of the adhesive when it is placed in contact with this adhesive after sticking, the quantity of soluble agent in the binder being adapted so that the security printing can form at least one visible spot revealing any attempt at unsticking with at least one such solvent.
[0009] EP-A-1349987 discloses a security paper comprising at least one zone reacting with non-polar solvents, this security paper being characterized in that it comprises a barrier impermeable to non-polar solvents between a first outer side of the security paper and the zone reacting with non-polar solvents.
[0010] However, the securement of security documents according to the prior art is expensive and has the disadvantage that it must be chosen and implemented from the design of the security documents.
SUMMARY OF THE INVENTION
[0011] An object of the present invention is that of providing security documents of the type comprising a support on which are inscribed personalization data, a security optical component covering at least a portion of the personalization data and an adhesive layer positioned between the support and the optical security component, allowing to improve the securement of the security documents by increasing the resistance to falsification. In this perspective, the applicant has advantageously found that the addition of a transparent anti-adhesive layer, positioned on the optical security component, fulfils this object.
[0012] In the present description and in the claims that follow, the terms “security document” are used in reference to any official identity document, such as, for example, a passport, an identity card, a driving license, a diploma or to any document, packaging or product bearing personalization data that are susceptible to be counterfeited and requiring a guarantee of authenticity and/or completeness.
[0013] In the present description and in the claims that follow, the terms “personalization data” are used in reference to information contained in the security document to be read with a naked eye or by a machine in order to identify and/or authenticate the security document. These personalization data can be data appearing in the form of photo, text containing for example the biographical data of the holder of the security document, data appearing in the form of symbols or numbers or in any other form permitting to identify and/or authenticate the security document.
[0014] In the present description and in the claims that follow, the term “surface”, when used in reference to the security document according to the invention, refers to the surface of the security document opposite to the support of the security document.
[0015] In the present description and in the claims that follow, the term “reflective” is used in reference to the reflection of light at least partially in the visible range. Thus, for example, a reflecting layer is a layer which can reflect light at least partially in the visible range.
[0016] In the present description and in the claims that follow, the term “transparent” is used in reference to the passage at least partial of light in the visible range through a medium. Thus, for example, a reflecting layer is a layer capable of at least partially letting light, in the visible range, go through.
[0017] According to a first aspect of the present invention, said object is achieved by a security document comprising a support on which are inscribed personalization data, an optical security component covering at least a portion of the personalization data, an adhesive layer positioned between the support and the optical security component and a transparent anti-adhesive layer, positioned on the optical security component.
[0018] The fact of adding a transparent anti-adhesive layer on the optical security component of the security document allows to make non-adhesive the surface of the security document and thus to prevent the peeling of the optical security component by using an adhesive film.
[0019] Advantageously, the security document presents a reinforced resistance to mechanical and chemical attacks. In addition, the porosity of the surface of the security document is decreased, which reduces the risks of penetration of foreign bodies due to the normal handling of the security document which could produce marks and/or local physicochemical degradations.
[0020] Advantageously, the surface of the security document becomes not printable. The falsifier cannot therefore attempt a falsification by surface printing.
[0021] According to a preferred embodiment, the anti-adhesive layer covers more than 90% of the surface of the security document. In another preferred embodiment, the anti-adhesive layer forms a first predetermined pattern.
[0022] Advantageously, the anti-adhesive layer having a first predetermined pattern allows to vary the surface characteristics, such as the total surface energy and the peeling tension, on the surface of the security document. Therefore, all falsification attempts with an adhesive film will lead to the appearance of a pattern corresponding to the first predetermined pattern and corresponding to the areas having more or less adhesion, i.e., having a character of wettability more or less great, with the adhesive film of the falsifier.
[0023] Advantageously, the first predetermined pattern is selected so that the peeling forces are inhomogeneous on the surface of the security document. The falsification of the security document is even more difficult because there is no preferred direction to peel the adhesive film and the optical security component for falsification purpose.
[0024] The constitutive elements of the first predetermined pattern can be for example screens, micro-lines, guilloches, significant elements, such as a logo or a slogan, that can be filled or drawn only by their (wired) contour. In a preferred embodiment, the first predetermined pattern comprises fixed or variable constitutive elements. In a preferred embodiment, the variable constitutive elements are specific either to the security document, or to the holder, or to the series of security documents.
[0025] According to a preferred embodiment, the first predetermined pattern is such that it allows to counteract the curvature of the security document after the lamination of the optical security component. Indeed, the lamination of the optical security component on the support of the security document usually causes the curvature of the security document. According to a preferred embodiment, the first predetermined pattern comprises constitutive elements perpendicular to the curvature of the security document.
[0026] According to an embodiment, the security document presents a surface having a reduced total surface energy relative to the surface energy of a security document according to the prior art. In other words, the security document presents a surface having a reduced wettability compared to the wettability of the surface of a security document according to the prior art.
[0027] Wetting describes the physical phenomena when three phases, of which at least one is liquid, are put into contact. As shown in FIGS. 1 a and 1 b , when liquid 103 is deposited on a solid surface 102 , in a gas 101 , either it spreads completely ( FIG. 1 a ) or it forms a drop with a contact angle θ with the solid ( FIG. 1 b ). The bigger the angle θ is, the greater the wettability of the solid is reduced.
[0028] In FIGS. 1 a and 1 b, γ S , is the interfacial tension between the solid 102 and the gas 101 , γ SL is the interfacial tension between the solid 102 and the liquid 103 and γ L is the interfacial tension between the liquid 103 and the gas 101 .
[0029] The surface energy can be measured by any suitable technique known by the man skilled in the art, and for example by measurement acquired with a GBX Scientific Instrumentation device, which provides measurements according to the approach of Owens-Wendt. This approach corresponds to the following equation:
[0000] cos θ=−1+2√{square root over (γ S d )}(√{square root over (γ L d )}/γ L )+2√{square root over (γ S nd )}(√{square root over (γ L nd )}/γ L )
[0030] wherein θ is the contact angle of the drop on the surface, γ S d and γ S nd are, respectively, the dispersive component and the non-dispersive component of the interfacial tension between the solid 102 and the gas 101 , γ L d and γ L nd , are, respectively, the dispersive component and the non-dispersive component of the interfacial tension between the liquid 103 and the gas 101 , and γ L is the interfacial tension between the liquid 103 and the gas 101 .
[0031] In a preferred embodiment, the anti-adhesive layer has an average total surface energy of less than 25 mN/m, and preferably less than 20 mN/m.
[0032] According to an embodiment, the security document presents a surface having reduced peeling characteristics compared to the peeling characteristics of the surface of a security document according to the prior art. In other words, the surface of the security document according to the invention has a reduced average peeling force compared to the average peeling force of the surface of a security document according to the prior art.
[0033] The peeling force can be measured by any suitable technique known by the man skilled in the art, for example, by a measurement, shown in FIG. 2 , according to an adaptation of the FINAT FTM 1 standard in which the peeling force is the force required to remove a strip of standard test adhesive material 104 , which was applied to the sample 105 , of the sample at an angle of 90° and at a speed of 1000 mm per minute (as shown by the arrow in FIG. 2 ). To perform this measurement, the standard test adhesive material is a 3M adhesive tape referenced as 3M-VHB, and is pasted to a polyester sheet having a thickness of 36 microns, the band of adhesive material has a width of 20 mm and the sample security document has a width of 85 mm.
[0034] In a preferred embodiment, the anti-adhesive layer has an average peeling force of less than 1 N, and preferably of less than 500 mN.
[0035] In a preferred embodiment, the anti-adhesive layer has an average thickness of less than 5 microns, and preferably between 1 and 2 microns.
[0036] In an embodiment, the anti-adhesive layer comprises at least a cross-linkable resin, a cross-linking initiator agent and a slip agent.
[0037] In a preferred embodiment, the crosslinkable resin comprises at least one of a polyester resin, an epoxy resin, a polyether resin, a polyol resin, a polyurethane resin or an acrylic resin. In a preferred embodiment, the crosslinkable resin is cross-linkable by UVs.
[0038] The crosslinking initiator agent is capable of initiating a crosslinking reaction of the crosslinkable resin. In a preferred embodiment, the crosslinking initiator agent is a photoinitiator or thermoinitiator agent. In a preferred embodiment, the photoinitiator agent is a radical or ionic agent. In a preferred embodiment, the photoinitiator is selected from benzophenone derivatives, ketones, phosphorus derivatives, and sulphur derivatives.
[0039] In a preferred embodiment, the slip agent comprises at least one of a reactive silicone or a wax.
[0040] In a preferred embodiment, the anti-adhesive layer further comprises a mono- or poly-functional, crosslinkable solvent. In a preferred embodiment, the solvent is crosslinkable by UVs.
[0041] According to a preferred embodiment, the anti-adhesive layer is crosslinked. Advantageously, this crosslinking prevents the subsequent dissolution of the anti-adhesive layer for malicious purposes by counterfeiters.
[0042] In a preferred embodiment, the anti-adhesive layer further comprises a physico-chemical marker that is not visible to the naked eye but can be revealed by the use of a suitable tool, such as a spectrometer, or by a specific light. Advantageously, the addition of a physicochemical marker allows strengthening the securement of the security document
[0043] According to an embodiment, the anti-adhesive layer comprises a material such that the surface of the security document diffuses, at least partially, light. According to a preferred embodiment, the anti-adhesive layer comprises a material such that the surface of the security document is at least partially matt. Advantageously, such an anti-adhesive layer can provide the security document according to the invention with a distinctive mark on the surface of the security document, thereby strengthening its securement.
[0044] The support comprises any suitable material known by the man skilled in the art. In a preferred embodiment, the support comprises at least one of natural paper, synthetic paper, and plastic material. In a preferred embodiment, the support is a multi-layered support, each layer comprising at least one of natural paper, synthetic paper, and plastic material. Preferably, the plastic material comprises at least one of polycarbonate, polyethylene, polyvinyl chloride, ABS (acrylonitrile butadiene styrene), polystyrene, PEC, polyethylene terephthalate or any combination of these materials.
[0045] In a preferred embodiment, the support has an average thickness comprised between 50 and 500 microns, and preferably between 80 and 120 microns.
[0046] The optical security component may comprise any suitable optical security element known by the man skilled in the art. In a preferred embodiment, the optical security component comprises at least one optically variable element, preferably at least one diffractive structure. In a preferred embodiment, the optical security component comprises at least one hologram.
[0047] According to a preferred embodiment, the optical security component covers at least a portion of the personalization data, and preferably all of the personalization data.
[0048] According to a preferred embodiment, the optical security component covers all of the support. In another preferred embodiment, the optical security component forms a second predetermined pattern covering at least a portion of the personalization data.
[0049] According to a preferred embodiment, the optical component has an average thickness comprised between 2 and 100 microns, and preferably between 4 and 40 microns.
[0050] In a preferred embodiment, the second predetermined pattern is continuous. In another preferred embodiment, the second predetermined pattern is discontinuous.
[0051] In a preferred embodiment, the optical security component comprises one transparent reflecting layer, positioned on the adhesive layer of the security document and a layer comprising at least one security optical element and positioned on the reflecting layer.
[0052] In a preferred embodiment, the reflecting layer has an average thickness comprised between 5 and 500 nm, preferably between 5 and 250 nm and preferably between 10 and 100 nm.
[0053] According to a preferred embodiment, the reflecting layer comprises at least a component having a high refractive index, for example greater than 2. In a preferred embodiment, the reflecting layer comprises at least one component selected from zinc sulphide, titanium dioxide or zirconium oxide.
[0054] In a preferred embodiment, the layer comprising at least one optical security element has an average thickness of less than or equal to 10 microns, and preferably comprised between 2 and 10 microns.
[0055] According to a preferred embodiment, the layer comprising at least one optical security element comprises a thermoformable varnish. In another preferred embodiment, the layer comprising at least one optical security element comprises at least one acrylic varnish.
[0056] In a preferred embodiment, the optical security element is a diffusing structure or a diffracting structure or a combination of different structure types.
[0057] In another preferred embodiment, the optical security component may further comprise at least one protective layer positioned on the layer comprising at least one optical security element.
[0058] The protective layer allows protecting the security document against at least one of dirt, scratches, chemical attacks. In a preferred embodiment, the protective layer comprises a polymer varnish. In a preferred embodiment, the protective layer has a thickness comprised between 0.1 and 1.5 microns, preferably between 0.2 and 0.5 microns.
[0059] The adhesive layer allows to weld the support and the optical security component together and comprises any suitable material known by the man skilled in the art. In a preferred embodiment, the adhesive layer comprises at least one heat-activable adhesive.
[0060] In a preferred embodiment, the adhesive layer comprises polymers having a melting point of between 40° C. and 200° C., preferably an acrylic copolymer-based adhesive in an aqueous dispersion or a solvent. In a preferred embodiment, the adhesive layer comprises at least one of an acrylic resin, a polyvinyl acetate, a vinyl thermoplastic resin, an adhesive comprising a copolymer in an aqueous dispersion or a solvent, an epoxy, a polyester, or a combination of these materials or materials with similar characteristics.
[0061] In a preferred embodiment, the adhesive layer has an average thickness comprised between 2 and 25 microns, preferably between 4 and 10 microns.
[0062] In a preferred embodiment, the adhesive layer comprises heat-reactivable adhesives requiring a post-crosslinking.
[0063] Another aspect of the present invention relates to a method of securement a security document comprising providing a security document to be secured comprising a support on which are inscribed personalization data, an optical security component covering at least a portion of the personalization data and an adhesive layer positioned between the support and the optical security component, and applying a transparent anti-adhesive layer on the optical security component.
[0064] In the prior art, the method for producing a security document comprises preparing an optical security component in the form of a laminate on a separable film, inscribing the personalization data on the support of the security document, lamining the optical security component on the support of the security document, and then removing the separable film so as to transfer only the laminate on the security document. The preparation of optical security component comprises, in general, applying an embossable layer on the separable film, embossing the embossable layer in order to integrate therein an optical security element, applying a transparent reflecting layer on the embossed layer, and then applying an adhesive layer on the reflecting layer.
[0065] Thus, according to the prior art, the lamination of the optical security component is the final step of the preparation of a security document. An anti-adhesive layer cannot be introduced into the structure of the optical security component because it would provoke inopportune detachments during the embossing process of the optical security component.
[0066] Advantageously, the method according to the invention allows for the introduction of the anti-adhesive layer into the security document after lamination of the optical security component on the support of the security document. This method can thus be implemented to any security document and at any time during the lifetime of the security document, for example, either at the beginning of its manufacture, or on a security document already in circulation.
[0067] The method of securement of a security document according to the invention comprises preferred steps that are performed in order to obtain a security document according to one or several preferred embodiments described above.
[0068] The security document to be secured is made by any suitable technique known to the man skilled in the art.
[0069] In a preferred embodiment, the anti-adhesive layer is applied according to a first predetermined pattern.
[0070] The anti-adhesive layer is applied to the optical security component by any suitable technique known by the man skilled in the art. According to a preferred embodiment, the anti-adhesive layer is applied on the optical security component by spraying, printing, or pad printing. In a preferred embodiment, the anti-adhesive layer is printed by ink jet printing or screen printing.
[0071] Advantageously, the application of the anti-adhesive layer on the security document by printing allows for high-resolution applications. Advantageously, printing of the anti-adhesive layer by screen printing enables a strong ink deposit. Advantageously, the printing of the anti-adhesive layer by ink jet printing allows for the application of the anti-adhesive layer according to a customisable pattern.
[0072] According to a preferred embodiment, the application of the anti-adhesive layer further comprises a step of crosslinking of the anti-adhesive layer. Advantageously, this step, which allows initiating the crosslinking of the anti-adhesive layer, allows preventing the subsequent dissolution of the anti-adhesive layer for malicious purposes.
[0073] According to a preferred embodiment, the application of the anti-adhesive layer further comprises a step of drying of the anti-adhesive layer.
[0074] According to a preferred embodiment, the crosslinking and/or drying are carried out under UVs.
[0075] In a preferred embodiment, the adhesive layer comprises heat reactivable adhesives requiring a post-crosslinking. In a preferred embodiment, the crosslinking of the adhesive layer is carried out together with the crosslinking of the anti-adhesive layer.
[0076] In a preferred embodiment, the anti-adhesive layer further comprises a mono- or poly-functional and crosslinkable solvent. In a preferred embodiment, the solvent is UV-crosslinkable, preferably by the same source of UVs than the crosslinkable resin of the anti-adhesive layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0077] The invention will now be described with reference to the accompanying drawings in which the Figures are not to scale and the dimensions of certain elements have been enlarged for illustrative purposes, and in which
[0078] FIGS. 1 a and 1 b illustrate the principle of wetting; FIG. 1 a illustrates the case of a high wettability and FIG. 1 b illustrates the case of a low wettability,
[0079] FIG. 2 illustrates the measurement of the peeling force of the security document according to the invention,
[0080] FIG. 3 shows an exploded cross-sectional view of the security document according to an embodiment of the present invention,
[0081] FIG. 4 shows an exploded cross-sectional view of the security document according to another embodiment of the present invention,
[0082] FIG. 5 shows an exploded cross-sectional view of the security document according to another embodiment of the present invention,
[0083] FIG. 6 a schematically shows the curvature of a security document of the prior art; FIG. 6 b shows a top view of a security document according to an embodiment of the present invention; FIG. 6 c shows a top view of a security document according to another embodiment of the present invention,
[0084] FIG. 7 schematically shows the method according to an embodiment of the present invention, and
[0085] FIG. 8 shows schematically the method according to another embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0086] FIG. 3 shows the layers of a security document 1 , for example, a passport page, in an exploded cross-sectional view for clarity, according to an embodiment of the present invention.
[0087] The security document 1 comprises a support 2 on which are inscribed personalization data 3 , an adhesive layer 4 , an optical security component 5 and an anti-adhesive layer 6 .
[0088] FIG. 4 shows the security document 1 in a cross-sectional view according to another embodiment of the present invention.
[0089] The security document 1 comprises a support 2 on which are inscribed personalization data 3 , an adhesive layer 4 , an optical security component 5 and an anti-adhesive layer 6 . The anti-adhesive layer 6 forms a first predetermined pattern 7 .
[0090] FIG. 5 shows the security document 1 in a cross-sectional view according to yet another embodiment of the present invention.
[0091] The security document 1 comprises a support 2 on which are inscribed personalization data 3 , an adhesive layer 4 , an optical security component 5 and an anti-adhesive layer 6 . The optical security component 5 forms a second predetermined pattern 8 .
[0092] For example, the support 2 has a basis weight of 80 g/m 2 and is constituted of 50% of cotton and 50% of wood. The average thickness of the support 2 is comprised between 80 and 120 microns. The optical security component 5 comprises a ZnS layer embossed with a diffracting structure and has an average thickness of 4 microns. The adhesive layer 4 has an average thickness of 10 microns.
[0093] According to the prior art illustrated in FIG. 6 a , the lamination of an optical security component on the support of a passport page 106 generally results in the curvature of the passport page 106 relative to the rest of the passport 107 .
[0094] FIG. 6 b shows a possible first predetermined pattern 7 allowing to counteract the curvature of the passport page after lamination of the optical security component on the passport page 1 . In this example, the first predetermined pattern 7 is constituted of three filled elements of different shapes.
[0095] FIG. 6 c shows another possible first predetermined pattern 7 allowing to counteract the curvature of the passport page 1 after lamination of the optical security component on the passport page 1 . In this example, the first predetermined pattern 7 is constituted of a layer hollowed out in three areas.
[0096] The method of securement of the security document 1 is described with reference to FIGS. 7 and 8 .
[0097] In FIG. 7 , according to an embodiment of the invention, the method of securement of the security document is implemented in a unit which complement an existing manufacturing line. The method first comprises the step 1 of printing the anti-adhesive layer on the optical security component. The printing can be done according to a first predetermined pattern. The method then comprises the step 2 of crosslinking and/or drying of the anti-adhesive layer.
[0098] For example, crosslinking is carried out using a UV lamp of a power of 130 W, such as a Mercury lamp, emitting UVAs, UVBs and UVCs. The crosslinking energy is for example about 500 mJ/cm 2 in UVBs.
[0099] In FIG. 8 , according to another embodiment of the present invention, the method of securement of the security document is implemented in a security documents personalization centre. This personalization centre implements the steps 1 and 2 for the inscription of the personalization data on the support of the security document and the lamination of the optical security component. The method of securement of the present invention is inserted in this process and comprises the steps 3 and 4 of printing the anti-adhesive layer and crosslinking and/or drying the anti-adhesive layer. Arrows 10 and 11 indicate the information flow from the central unit to the inscription and printing stations (Steps 1 and 3 ).
EXAMPLES
[0100] The peeling force of a security document according to the invention and of a security document according to the prior art without the anti-adhesive layer was measured.
[0101] The security document according to the prior art comprises a support having a basis weight of 80 g/m 2 and consists of 50% of cotton and 50% of wood, an optical security component and an anti-adhesive layer comprising a reactive silicone, a cationic photoinitiator agent and a UV crosslinkable resin.
[0102] The used measurement method is shown in FIG. 2 . A strip of standard test adhesive material 104 , i.e. a 3M adhesive tape referenced 3M-VHB, of 20 mm in width and laminated on a polyester sheet with a thickness of 36 microns, has been applied to samples 105 of 85 mm in width. The strip 104 was removed from the samples 105 at an angle of 90° and a speed of 1000 mm per minute (represented by the arrow in FIG. 2 ).
[0103] The average peeling force measured for a security document of the prior art without an anti-adhesive layer is 20 N and the adhesion of the standard test adhesive material on the security document is such that a cohesive rupture of the paper, which is defibered, is obtained.
[0104] The average peeling force measured for a security document according to the invention having an anti-adhesive layer is 0.5 mN.
[0105] In parallel, measures of the average total surface energy at the surface of the security document according to the invention and the security document according to the prior art have been performed.
[0106] The average total surface energy measured at the surface of the security document according to the invention is about 17.9 mN/m while the average total surface energy measured at the surface of the security document according to the prior art is 47.9 mN/m.
[0107] The invention thus described has the following advantage among others.
[0108] The security documents according to the invention allow preventing their falsification by peeling of the security laminate with an adhesive film. The methods of securement of the security documents according to the invention are implementable at any time during the life of the security documents as well as on an existing security documents personalization line without the need to modify the optical security component and/or the security document and therefore, independently of the supplier of said optical security component and/or said security document.
[0109] The invention has been described in particular embodiments illustrated by the different figures, which are not limitative. Further embodiments may be considered by the man skilled in the art such as, for example, the choice of materials, deposit techniques of the various layers, predetermined patterns.
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The present invention relates to a method of securement of a security document comprising providing a security document to be secured comprising a support on which are inscribed personalization data, an optical security component covering at least a portion of the personalization data and an adhesive layer positioned between the support and the optical security component, and applying a transparent anti-adhesive layer on the optical security component.
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TECHNICAL FIELD OF THE INVENTION
[0001] The present invention concerns the field of jewelry and costume jewelry, and in particular its object is a customizable ornament that is suitable for forming, or for being incorporated in, a product such as a bracelet, a necklace, a ring, earrings, a pendant or any other similar type of personal accessory item. The customization should be intended with reference to both the possibility of the user of “creating” the appearance of his own accessory item in the point of sale at the moment of purchase selecting from various solutions available, and modifying the appearance of a product that has already been purchased by replacing parts that are sold separately as spare parts.
BACKGROUND OF THE INVENTION
[0002] As it is known, for accessories of this kind, customization is very strongly requested by the customers and push retailers and consequently the manufacturers to research solutions that allow such requirement to be satisfied in the most functional and practical manner possible, with a high quality result in terms of its appearance.
[0003] Among the solutions proposed in this field, some that have recently gained favour are those in which a replaceable decorative insert, in the form of a disc-shaped plate or in any case in a different shape, is fixed in a reversible manner to a base through magnetic or snap-fitting means which, because of their simplicity, make it possible for the user himself to assemble or disassemble it.
[0004] Indeed, it is the disassembling that leads to quite a serious technical problem, due to the fact that the reversible fixing system of the insert at the base must on one hand be, as mentioned, easily reversible, but at the same time it must ensure high secureness (so as to minimise the risk of the insert being accidentally lost or removed). These are requirements that are in some way opposite to one another, and that known solutions have not been able to combine in a completely satisfactory manner.
[0005] In fact, since it is necessary to assign a priority to the security requirements, disassembling methods are proposed that are not suitably simple and intuitive, requiring acting upon the rear area of the base (i.e. that opposite to the front area on which the insert is exposed), which is not always very accessible, said actions sometimes requiring a certain amount of skill, or effort, or the use of special accessory tools, with small dimensions, that are not easy to handle and that can be easily lost.
SUMMARY OF THE INVENTION
[0006] The present invention, on the other hand, proposes a customizable ornament that is capable of overcoming such problems, thanks to a system for fixing the base to the insert that is simultaneously secure and easily reversible, without requiring difficult manoeuvres (especially on the rear side of the base), or accessory tools. This with a structure that is in any case elementary and cost-effective providing a result in terms of its appearance that is elegant and particularly appreciable.
[0007] According to the present invention, an ornament comprises the essential characteristics according to the independent attached claim 1 . Other important characteristics are defined by the dependent claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The characteristics and the advantages of the ornament according to the invention shall become clearer from the following description of an embodiment thereof, given as an example and not for limiting purposes with reference to the attached drawings, in which:
[0009] FIG. 1 shows an exploded side view of the ornament according to the present invention.
[0010] FIGS. 2 and 3 show the same exploded view in axonometric views from a point of view that is shifted towards the rear side and towards the front side of the ornament, respectively;
[0011] FIGS. 4 a to 4 d , and 5 a to 5 d represent various subsequent steps of the procedure for assembling the ornament, through axonometric views that are analogous to and correspond to those of FIGS. 2 and 3 , respectively; and
[0012] FIG. 6 is a perspective view of an example of a bracelet obtained with a plurality of ornaments according to the previous figures, represented without the respective inserts.
DETAILED DESCRIPTION OF THE INVENTION
[0013] With reference to the above figures, an ornament according to the invention comprises a base 1 , in the example having an overall cylindrical shape, the periphery of which is defined by a ring-like belt 11 developing symmetrically around a central axis X. A flat diaphragm 12 extends inside the belt 11 perpendicular to the axis X and, in cooperation with the belt itself, it forms two concavities, a front concavity or seat 13 and a rear concavity 14 , respectively. The outer surface 11 a of the belt 11 has two circumferential grooves 11 b, for example that develop according to two opposite arcs in the area of the belt corresponding to the rear concavity 14 .
[0014] An axial protrusion 15 projects from the diaphragm 12 centrally inside the rear concavity 14 , said protrusion being centrally hollow due to a passage 16 opening, at one end, onto the same diaphragm and, at the opposite end, on a free end 15 a of the protrusion 15 . The section of the passage 16 is elongated according to a diametrical axis, with a central portion 16 a which, enlarged with respect to the thickness (crosswise dimension) of end portions 16 b, takes up a substantially cylindrical configuration. The free end 15 a of the protrusion 15 moreover has a pair of recesses 17 , diametrically aligned along a direction that is perpendicular with respect to the diameter along which the hollow corresponding to the section of the passage 16 (see in particular FIG. 2 ) runs.
[0015] The front concavity or seat 13 is intended to fittingly house an insert 2 that is substantially mushroom-shaped, comprising more precisely a head 21 , a front face 21 a of which, variously decorated or in any case customized, flat or in relief, remains exposed and represents the characterising aesthetic element of the ornament. From the head 21 , on the side opposite with respect to the front face 21 a, a key shaped stem 22 projects, specifically in the shape of a T in the example, having an axial shaft 22 a and a cross piece 22 b at the free end.
[0016] The stem 22 is suitable for penetrating the passage 16 of the base 1 , with the shaft 22 a taking up the central portion 16 a and the cross piece 22 b inserting in the end portions 16 b. The axial extension of the stem 22 is moreover such that, when the head 21 abuts against the diaphragm 12 , the cross piece 22 b comes out from the passage 16 , beyond the free end 15 a of the protrusion 15 inside the rear concavity 14 . In such a configuration the insert can be freely rotated around the axis X; more precisely the central cylindrical portion 16 a of the passage 16 guides the rotation of the shaft 22 a , with the cross piece 22 b that can thus be arranged at the recesses 17 (this will be further considered in greater detail hereafter)
[0017] Between the insert 2 , or more precisely the head 21 , and the base 1 , or more precisely the diaphragm 12 , according to the invention there are further provided elastic means 3 , which are suitable for opposing the displacement of the head 21 towards the diaphragm 12 , and consequently for urging the same head towards the front side. Such elastic means preferably take up the configuration of a laminar disc 3 , suitably shaped in accordance with the perimeter of the front seat 13 , placed over and in contact with the diaphragm 12 . The disc 3 has a central window 31 with an elongated shape that is congruent with that of the passage 16 of the base 1 , and a pair of tabs 32 extending from respective ends of the window 31 on the rear side or face. Such tabs 32 are suitable for being folded so as to hook onto the diaphragm 12 , indeed on the rear side inside the rear concavity 14 , acting as elements for anchoring the disc to the base 1 .
[0018] Two leaf portions 33 are raised from the plane of the disc 3 and constitute the elastically active component, since they react elastically to a bending that, caused by a force directed axially from the front side (just like that which is exerted by the head 21 of the insert 2 when it is inserted inside the seat 13 ), tends to move them closer to the diaphragm 12 . Advantageously, the laminar portions 33 are two circular segments that evolve peripherally along arcs that are diametrically opposite to one another, simply defined by shaped cuts that leave the portions fixedly attached with one end to the rest of the disc, and free at the opposite end which reaches the position that is the most raised from the plane of the same disc. Again preferably, the two portions 33 are symmetrical to one another, in the sense that the (raised) free ends of the portions are aligned along one same diameter, the same applying to the ends attached to the disc.
[0019] With particular reference to figures from 4 a to 4 d, the procedure for connecting the insert 2 to the base 1 is carried out manually as follows (the spring 3 being previously anchored to the base 1 like what has just been described). The passage 16 of the base 1 is penetrated by the stem 22 of the insert 2 ( FIGS. 4 a , 5 a ), until the head 21 comes into contact with the raised ends of the portions 33 ( FIGS. 4 b , 5 b ). At this stage, in order to continue the run of the head 21 towards the diaphragm 12 it is necessary to lightly force it (arrow F1), so as to overcome the elastic resistance of the portions 33 .
[0020] When such an end stop is finally reached ( FIGS. 4 c , 5 c ) the cross piece 22 b comes out from the passage 16 and it is possible to give the insert a rotation (to that moment prevented by the abutment of the same cross piece itself against the inner walls of the passage 16 ), like the arrows F2, so as to bring the cross piece, with an angular displacement of 90°, to the recesses 17 . By finally releasing the insert, the action of the elastic portions 33 again pushes the head 21 upwards, and consequently to makes the cross piece 22 b snap-fit inside the recesses 17 , suitably sized so as to house the ends thereof ( FIGS. 4 d , 5 d , arrow F3).
[0021] In such a condition, corresponding to the final configuration, or configuration of use of the ornament, the insert is fixedly locked in position by the abutment of the cross piece against the free end 15 a of the protrusion 15 , urged by the elastic portions 33 . Only an axial pressure exerted from the front side on the outside of the head 21 can free the cross piece again from the engagement with the recesses 17 , overcoming the elastic resistance of the portions 33 , and thus making it possible, after another 90° rotation (reversed or consecutive to the previous one), to re-establish the conditions for making the stem 22 come out from the passage 16 of the base 1 . In such a way the insert 2 can be removed so as to be replaced with a differently decorated insert, by again following the assembly procedure described above.
[0022] Thanks to the particular configuration of the elastic means 33 , together with a suitable selection of material used (typically but not necessary metal) for its rigidity characteristics, it is possible to calibrate the elastic hindering force exerted, so as to reach an optimal compromise between the requirements of secureness and those of relative simplicity of the assemble/disassembly steps. Indeed, it is possible to make the axial force necessary for the release fairly high so as to prevent, or in any case minimize, the risk of an undesired release, without however exceeding a threshold that would make the release too difficult to carry out when removing/replacing the insert.
[0023] Also the particular configuration of the engagement of the stem with the protrusion of the base decisively collaborates in reaching such a compromise. Thanks to such a configuration the movement that leads to the release is a composite movement (pressure and rotation), therefore an adequate degree of security is ensured even when a low release pressure is set, since it is highly improbable for an accidental, involuntary or fraudulent action to be able to exert an axial pressure and at the same time the necessary rotation.
[0024] One material that can be used for the spring 3 is for example copper alloys (for example Cu—Be alloys), spring steel, but other metal or non-metal materials with a suitable rigidity can be used. For the rest of the ornament the reference materials can be those typically used in the field, or rather, materials that are precious, semi-precious or not precious for the base and for the body of the insert, with stones that are precious or semi-precious, enamels, glass, resins or anything else for creating the decoration of the front face 21 a of the head 21 . The term decoration must, furthermore, be taken broadly speaking, being it possible for functional elements such as a watch case, a compass or anything else to be included.
[0025] With reference to FIG. 6 , the ornament according to the invention can be for example integrated in a bracelet, and for such a purpose the outer grooves 11 b of the belt 11 can be used for the engagement of a lace 4 that forms the core of the bracelet and that, through known and per se obvious knotting techniques, connects in series a plurality of ornaments to one another the customization designs of which can also be selected so as to obtain a conceptual association or simply be combined according to a coherence of style. Of course, other types of jewels such as earrings, pendants, chokers, necklaces in general, rings can be made with the present ornament, alone or in series, integrating it or integrating them as desired with the base structure of the jewel with any suitable method, selected among those known.
[0026] From this last point of view, it should be noted that the solution according to the invention is such as to not require—for the assembly and disassembly operations—acting upon the rear part, therefore, when enclosing the ornament itself in a complex product there is maximum construction freedom, with embodiments that can also foresee making the aforementioned rear part inaccessible. The ornament can therefore, for example, be welded or in any case fixed on to the outer face of a bracelet with a metal plate, however other applications on belts, bags or other similar personal accessories are not excluded.
[0027] The ornament according to the present invention ultimately achieves a secure and functional solution, which does not require particular strength, or skill, or tools, is cost-effective to make and does not have any negative effect on the appearance.
[0028] Of course, the outline of the head of the insert and correspondingly of the base, just like the configuration of the elastic means and in general the strictly constructive provisions may vary with respect to the advantageous ones of the embodiment described and illustrated here. The invention is not indeed limited to such a preferred embodiment, and other embodiments are possible belonging to the same inventive concept, all covered by the scope of protection of the following claims.
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The present invention concerns the field of jewelry and costume jewelry, and in particular its object is a customizable ornament that is suitable for forming, or for being incorporated in, a product such as a bracelet, a necklace, a ring, earrings, a pendant or any other similar personal accessory item.
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BACKGROUND
The present disclosure relates generally to conserving power in link aggregation groups.
As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option is an information handling system (IHS). An IHS generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes. Because technology and information handling needs and requirements may vary between different applications, IHSs may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in IHSs allow for IHSs to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, IHSs may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
Additionally, some embodiments of information handling systems include non-transient, tangible machine-readable media that include executable code that when run by one or more processors, may cause the one or more processors to perform the steps of methods described herein. Some common forms of machine readable media include, for example, floppy disk, flexible disk, hard disk, magnetic tape, any other magnetic medium, CD-ROM, any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes, RAM, PROM, EPROM, FLASH-EPROM, any other memory chip or cartridge, and/or any other medium from which a processor or computer is adapted to read.
Computer networks form the interconnection fabric that enables reliable and rapid communications between computer systems and data processors that are both in close proximity to each other and at distant locations. These networks create a vast spider web of intranets and internets for handling all types of communication and information. Making all of this possible is a vast array of network switching products that make routing decisions in order to deliver packets of information from a source system or first network node to a destination system or second network node. Due to the size, complexity, and dynamic nature of these networks, sophisticated network switching products are often required to implement the interconnection fabric. This can be further complicated through other networking trends such as network virtualization.
Many networks utilize parallelization and other techniques to improve the routing function between two network nodes. By employing parallelization, redundancy is built into a network so that it is possible that more than one path exists between any two nodes. This provides suitably aware network switching products with the ability to select between the redundant paths to avoid network congestion, balance network loads, and/or to avoid failures in the network. Parallelization also provides the ability to handle more network traffic between two nodes than is possible when parallelization is not utilized. In some implementations the parallelization is treated in a more formalized fashion in the form of link aggregation groups (LAGs), in which multiple network links are often bundled into a group to support the parallelization function. For suitably aware network switching products, the LAG can offer a flexible option to select any of the network links in the LAG for routing network traffic towards the next node in the path towards the traffic's final destination. And while LAGs offer additional flexibility in network topologies, they may also add complexity to the routing function and management of the network switching products to which they are attached. And as each network link added to a LAG may increase the quantity of network traffic that can be handled by the LAG, it may also add to the power consumption of both network switching products associated with the network link.
Accordingly, it would be desirable to provide improved network switching products that can dynamically activate and deactivate network links within a LAG to reduce the power consumption of the associated network switching products.
SUMMARY
According to one embodiment, a method of reducing power consumption in a network switching unit includes detecting whether conditions are suitable for reducing power consumption in a first network switching unit. The first network switching unit includes a link aggregation group (LAG) and a plurality of communication ports, each communication port configured to couple the first network switching unit to a second network switching unit using a corresponding network link selected from a plurality of network links, and wherein the plurality of network links are assigned to the LAG. The method further includes requesting network link deactivation by sending a link deactivation request to the second network switching unit, determining whether the link deactivation request is approved, determining a first network link selected from the plurality of network links to deactivate, deactivating the first network link from use by the LAG, and reducing power supplied to the first network link.
According to another embodiment, a method of reducing power consumption in a network switching unit includes receiving a link deactivation request by a first network switching unit from a second network switching unit. The first network switching unit includes a link aggregation group (LAG) and a plurality of communication ports, each communication port configured to couple the first network switching unit to the second network switching unit using a corresponding network link selected from a plurality of network links, and wherein the plurality of network links are assigned to the LAG. The method further includes determining whether the link deactivation request is acceptable, in response to determining that the link deactivation request is not acceptable, denying the link deactivation request, in response to determining that the link deactivation request is acceptable, confirming the link deactivation request, determining a first network link selected from the plurality of network links to deactivate, deactivating the first network link from use by the LAG, and reducing power supplied to the first network link.
According to yet another embodiment, an information handling system includes a first network switching unit. The first network switching unit includes a link aggregation group (LAG) and a plurality of communication ports, each communication port configured to couple the first network switching unit to a second network switching unit using a corresponding network link selected from a plurality of network links, and wherein the plurality of network links are assigned to the LAG. The first network switching unit is configured to detect whether conditions are suitable for reducing power consumption, request network link deactivation by sending a link deactivation request to the second network switching unit, determine whether the link deactivation request is approved, determine a first network link selected from the plurality of network links to deactivate, deactivate the first network link from use by the LAG, and reduce power supplied to the first network link.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 a shows a simplified diagram of a network according to some embodiments.
FIG. 1 b shows a simplified diagram of the network with a network link deactivated according to some embodiments.
FIG. 2 shows a simplified diagram of a method of reducing power consumption in a network switching unit according to some embodiments.
FIG. 3 is a simplified diagram of a method of reducing power consumption in a network switching unit according to some embodiments.
FIG. 4 is a simplified diagram of a method of activating a network link in a network switching unit according to some embodiments.
FIG. 5 is a simplified diagram of a method of activating a network link in a network switching unit according to some embodiments.
FIG. 6 is a simplified diagram of an extension to an actor and a partner state of a LACP data unit (LACPDU) according to some embodiments.
In the figures, elements having the same designations have the same or similar functions.
DETAILED DESCRIPTION
In the following description, specific details are set forth describing some embodiments consistent with the present disclosure. It will be apparent, however, to one skilled in the art that some embodiments may be practiced without some or all of these specific details. The specific embodiments disclosed herein are meant to be illustrative but not limiting. One skilled in the art may realize other elements that, although not specifically described here, are within the scope and the spirit of this disclosure. In addition, to avoid unnecessary repetition, one or more features shown and described in association with one embodiment may be incorporated into other embodiments unless specifically described otherwise or if the one or more features would make an embodiment non-functional.
For purposes of this disclosure, an IHS may include any instrumentality or aggregate of instrumentalities operable to compute, classify, process, transmit, receive, retrieve, originate, switch, store, display, manifest, detect, record, reproduce, handle, or utilize any form of information, intelligence, or data for business, scientific, control, entertainment, or other purposes. For example, an IHS may be a personal computer, a PDA, a consumer electronic device, a display device or monitor, a network server or storage device, a switch router or other network communication device, or any other suitable device and may vary in size, shape, performance, functionality, and price. The IHS may include memory, one or more processing resources such as a central processing unit (CPU) or hardware or software control logic. Additional components of the IHS may include one or more storage devices, one or more communications ports for communicating with external devices as well as various input and output (I/O) devices, such as a keyboard, a mouse, and a video display. The IHS may also include one or more buses operable to transmit communications between the various hardware components.
FIG. 1 a shows a simplified diagram of a network 100 according to some embodiments. As shown in FIG. 1 a , the network 100 may include a network switching unit 110 and a network switching unit 120 . The network switching unit 110 may include one or more communication ports 131 - 133 . Each of the one or more communication ports 131 - 133 may be coupled to a corresponding one of one or more network links 141 - 143 . Communication port 131 may be coupled to network link 141 , communication port 132 may be coupled to network link 142 , and communication port 133 may be coupled to network link 143 . The network switching unit 120 may include one or more communication ports 151 - 153 . Each of the one or more communication ports 151 - 153 may be coupled to a corresponding one of the one or more network links 141 - 143 . Communication port 151 may be coupled to network link 141 , communication port 152 may be coupled to network link 142 , and communication port 153 may be coupled to network link 143 .
Network switching unit 110 may route network traffic to network switching unit 120 by sending it to any one of the communication ports 131 - 133 where it is sent on the corresponding one of the network links 141 - 143 toward network switching unit 120 . Similarly, network switching unit 120 may route network traffic to network switching unit 110 by sending it to any one of the communication ports 151 - 153 where it is sent on the corresponding one of the network links 141 - 143 toward network switching unit 110 . Thus, the network links 141 - 143 can provide parallel and alternative network paths between the network switching unit 110 and the network switching unit 120 . The parallel nature of the network links 141 - 143 may be formalized in each of the network switching units 110 and 120 through the use of link aggregation groups. Network switching unit 110 may group the network links 141 - 143 into a LAG 161 . When network switching unit 110 desires to route network traffic to network switching unit 120 it may route the network traffic using LAG 161 , leaving the decision of which of the network links 141 - 143 and corresponding communication ports 131 - 133 to use to a LAG hashing algorithm. Similarly, network switching unit 120 may group the network links 141 - 143 into a LAG 162 . When network switching unit 120 desires to route network traffic to network switching unit 110 it may route the network traffic using LAG 162 .
Because network utilization may change based on the amount of network traffic being routed and/or the source(s) and destination(s) of the network traffic, the amount of network traffic that needs to be handled by network links 141 - 143 may increase or decrease. A network designer may generally choose the number of parallel network links 141 - 143 between the network switches 110 and 120 based on an expected maximum traffic load to reduce a potential for a loss of network traffic. However, there may be times when the actual traffic load being handled by network links 141 - 143 may be significantly less than the expected maximum traffic load or even non-existent. A ratio of the actual traffic load to a maximum traffic load that can be handled by a LAG is often referred to as the utilization for the LAG. A low utilization may indicate a low traffic load and a high utilization may indicate a high traffic load. In some embodiments, where there is an extended period of time where the utilization is low, it may be advantageous to deactivate one or more of the network links in a LAG to reduce power consumption. In some embodiments, it may be advantageous to reduce power consumption in the LAG for other reasons. In some embodiments, power consumption may be reduced to lower a need for heat dissipation and to lower the temperature of the network switching units 110 and 120 . In some embodiments, power consumption may be reduced to lower a peak power demand. In some embodiments, power consumption may be reduced based on a time of day.
FIG. 1 b shows a simplified diagram of the network 100 with the network link 143 deactivated according to some embodiments. As shown in FIG. 1 b , the network link 143 has been deactivated to reduce, for example, power consumption. Network traffic may now only move between the network switching units 110 and 120 using network links 141 and 142 . Network link 143 may also be deactivated for use in LAGs 161 and 162 so that the LAG hashing algorithms of network switching units 110 and 120 will not route network traffic using network link 143 . Because network link 143 is deactivated, network switching unit 110 may reduce or remove power from network link 143 . In some embodiments, network switching unit 110 may also reduce or remove power from communication port 133 . In some embodiments, network switching unit 110 may also reduce or remove power from other circuitry associated with communication port 133 and/or network link 143 . Network switching unit 120 may similarly reduce or remove power from network link 143 , communication port 153 , and/or other circuitry associated with communication port 153 and/or network link 143 . Thus, the overall power consumption of the network switching units 110 and 120 , as well as the network 100 may be reduced.
As discussed above and further emphasized here, FIGS. 1 a and 1 b are merely examples, which should not unduly limit the scope of the claims. One of ordinary skill in the art would recognize many variations, alternatives, and modifications. According to some embodiments, there may be fewer than three or more than three network links 141 - 143 coupling the network switching units 110 and 120 .
FIG. 2 shows a simplified diagram of a method 200 of reducing power consumption in a network switching unit according to some embodiments. As shown in FIG. 2 , the method 200 includes a process 210 for detecting power conservation conditions, a process 220 for requesting network link deactivation, a process 230 for receiving a response to the request, a process 240 for determining whether the request was confirmed, a process 250 for negotiating a network link to deactivate, a process 260 for deactivating the network link from use by a LAG, and a process 270 for reducing the network link power. According to certain embodiments, the method 200 of reducing power consumption in a network switching unit can be performed using variations among the processes 210 - 270 as would be recognized by one of ordinary skill in the art. According to some embodiments, the process 230 is optional and may be omitted. In some embodiments, one or more of the processes 210 - 270 may be implemented, at least in part, in the form of executable code stored on non-transient, tangible, machine readable media that when run by one or more processors in one or more network switching units (e.g., the network switching units 110 and/or 120 ) may cause the one or more processors to perform one or more of the processes 210 - 270 .
At the process 210 , a network switching unit (e.g., the network switching unit 110 and/or 120 ) may detect whether network conditions are suitable for reducing power consumption on one of the network switching unit's LAGs (e.g., the LAG 161 and/or 162 ). According to some embodiments, power consumption may be reduced when a utilization of the LAG falls below a minimum utilization threshold for a period of time. In some embodiments, the minimum utilization threshold may be 10% or lower. In some embodiments, the minimum utilization threshold may be 20% or lower. In some embodiments, the minimum utilization threshold may be set as part of the configuration of the network switching unit. In some embodiments, the minimum utilization threshold may be set using a configuration utility. In some embodiments, the minimum utilization threshold may be stored in one or more memory devices (e.g., ROM, RAM, PROM, EPROM, FLASH-EPROM, and/or any other memory chip or cartridge) coupled to the network switching unit. In some embodiments, the minimum utilization threshold may be dynamic based on a time of day and/or other network settings and/or conditions. In some embodiments, the period of time may be as short as a second or less. In some embodiments, the period of time may be as short as a minute or less. In some embodiments, the period of time may be 5-10 minutes or more in length. In some embodiments, the period of time may be set as part of the configuration of the network switching unit. In some embodiments, the period of time may be set using a configuration utility. In some embodiments, the period of time may be stored in one or more memory devices (e.g., ROM, RAM, PROM, EPROM, FLASH-EPROM, and/or any other memory chip or cartridge) coupled to the network switching unit. In some embodiments, the period of time may be dynamic based on a time of day and/or other network settings and/or conditions.
According to some embodiments, power consumption may be reduced when a temperature of the network switching unit exceeds a maximum temperature threshold. In some embodiments, the maximum temperature threshold may be 70 degrees centigrade or higher. In some embodiments, the maximum temperature threshold may be 85 degrees centigrade or higher. In some embodiments, the maximum temperature threshold may be 125 degrees centigrade or higher. In some embodiments, the maximum temperature threshold may be set as part of the configuration of the network switching unit. In some embodiments, the maximum temperature threshold may be set using a configuration utility. In some embodiments, the maximum temperature threshold may be stored in one or more memory devices (e.g., ROM, RAM, PROM, EPROM, FLASH-EPROM, and/or any other memory chip or cartridge) coupled to the network switching unit. In some embodiments, the maximum temperature threshold may be dynamic based on a time of day and/or other network settings and/or conditions.
According to some embodiments, power consumption may be reduced based on a time of day.
According to some embodiments, power consumption may be reduced based on one or more of the factors described above. In some embodiments, any logical and/or temporal combination of the one or more factors may be considered.
At the process 220 , the network switching unit makes a request for link deactivation. According to some embodiments, the network switching unit may select a LAG (e.g., the LAG of process 210 whose utilization is below the minimum utilization threshold). In some embodiments, the network switching unit may send a network link deactivation message to a neighboring network switching unit (e.g., the network switching unit 120 and/or 110 ) using one of the network links (e.g., the network links 140 - 143 ) in the LAG. In some embodiments, the link deactivation message may ask the neighboring network switching unit whether it is willing to deactivate one of their shared network links.
At the optional process 230 , the network switching unit receives a response to the link deactivation request. According to some embodiments, the network switching unit may receive a response message on one of the network links in the LAG. In some embodiments, the response message may include information indicating whether the neighboring network switching unit is willing to deactivate one of their shared network links.
At the process 240 , the network switching unit may determine whether the network link deactivation request is confirmed. According to some embodiments, the network switching unit examines the response message. According to some embodiments, the network deactivation request may not be confirmed when no response message is received. In some embodiments, the network deactivation request may not be confirmed when a response message is not received during a timeout period following the making of the deactivation request. In some embodiments, the timeout period is several milliseconds. In some embodiments, the timeout period is a second or longer. In some embodiments, the timeout period may be set as part of the configuration of the network switching unit. In some embodiments, the timeout period may be set using a configuration utility. In some embodiments, the timeout period may be stored in one or more memory devices (e.g., ROM, RAM, PROM, EPROM, FLASH-EPROM, and/or any other memory chip or cartridge) coupled to the network switching unit. In some embodiments, the timeout period may be dynamic based on a time of day and/or other network settings and/or conditions. If the network switching unit determines that the network link deactivation request has not been confirmed, the method 200 returns to process 210 .
At the process 250 , the network switching unit and the neighboring network switching unit may negotiate which network link should be deactivated. According to some embodiments, the network link is selected based on a mutually agreed upon criteria. In some embodiments, the network link, from among the active network links, with a largest ID number is selected. In some embodiments, the network link, from among the active network links, with a smallest ID number is selected. According to some embodiments, the network switching unit and the neighboring switching unit may exchange one or more negotiation messages to determine the network link to deactivate.
At the process 260 , the network switching unit may deactivate the network link from use by the LAG. According to some embodiments, the network link may be removed from consideration by a LAG hashing algorithm used to select from among the network links associated with the LAG.
At the process 270 , the network switching unit may reduce power provided to the network link. According to some embodiments, the network switching unit may reduce some power or remove all power to the network link. According to some embodiments, the network switching unit may reduce or remove power from a communication port (e.g., one of the communication ports 131 - 133 and/or 151 - 153 ) corresponding to the network link. According to some embodiments, the network switching unit may also reduce or remove power from other circuitry associated with the communication port and/or the network link.
As discussed above and further emphasized here, FIG. 2 is merely an example, which should not unduly limit the scope of the claims. One of ordinary skill in the art would recognize many variations, alternatives, and modifications. According to some embodiments, upon completion of the process 270 , the method 200 may return to process 210 to determine whether one or more additional network links may be deactivated.
FIG. 3 is a simplified diagram of a method 300 of reducing power consumption in a network switching unit according to some embodiments. As shown in FIG. 3 , the method 300 includes a process 310 for receiving a network link deactivation request, a process 320 for determining whether deactivation of a network link is acceptable, a process 330 for denying the request, a process 340 for confirming the request, a process 350 for negotiating a network link to deactivate, a process 360 for deactivating the network link from use by a LAG, and a process 370 for reducing the network link power. According to certain embodiments, the method 300 of reducing power consumption in a network switching unit can be performed using variations among the processes 310 - 370 as would be recognized by one of ordinary skill in the art. According to some embodiments, the process 330 is optional and may be omitted. In some embodiments, one or more of the processes 310 - 370 may be implemented, at least in part, in the form of executable code stored on non-transient, tangible, machine readable media that when run by one or more processors in one or more network switching units (e.g., the network switching units 110 and/or 120 ) may cause the one or more processors to perform one or more of the processes 310 - 370 .
At the process 310 , a network switching unit (e.g., the network switching unit 110 and/or 120 ) may receive a network link deactivation request. In some embodiments, the network link deactivation request may be the network link deactivation request from process 220 . In some embodiments, the network link deactivation request may be in the form of a network link deactivation message sent by a neighboring network switching unit (e.g., the network switching unit 120 and/or 110 ) using one of the network links (e.g., the network links 140 - 143 ) in a LAG (e.g., the LAG 162 and/or 161 ).
At the process 320 , the network switching unit determines whether deactivation of a network link is acceptable. According to some embodiments, the network switching unit may make its determination using one or more factors similar to the one or more factors used in the process 210 to detect whether network conditions are suitable for reducing power consumption. In some embodiments, the network switching unit may consider a utilization of the LAG. In some embodiments, the network switching unit may consider a temperature of the network switching unit. In some embodiments, the network switching unit may consider a time of day. In some embodiments, any logical and/or temporal combination of the one or more factors may be considered. According to some embodiments, the network switching unit may recognize that it has network traffic to route to the neighboring network switching unit that the neighboring network switching may not have been able to consider when it made the network link deactivation request. If the network switching unit determines that deactivation of a network link is not acceptable, the method 300 moves to process 330 . Otherwise, the method 300 moves to process 340 .
At the optional process 330 , the network switching unit denies the deactivation request. According to some embodiments, the network switching unit may send a response message on one of the network links in the LAG. In some embodiments, the response message may include information indicating that the network switching unit is not willing to deactivate one of its network links. In some embodiments, the response message may be the response received by the neighboring network switching device in process 230 .
At the process 340 , the network switching unit confirms the deactivation request. According to some embodiments, the network switching unit may send a response message on one of the network links in the LAG. In some embodiments, the response message may include information indicating that the network switching unit is willing to deactivate one of its network links. In some embodiments, the response message may be the response received by the neighboring network switching device in process 230 .
At the process 350 , the network switching unit and the neighboring network switching unit may negotiate which network link should be deactivated. According to some embodiments, the network link is selected based on a mutually agreed upon criteria. In some embodiments, the network link, from among the active network links, with a largest ID number is selected. In some embodiments, the network link, from among the active network links, with a smallest ID number is selected. According to some embodiments, the network switching unit and the neighboring switching unit may exchange one or more negotiation messages to determine the network link to deactivate. According to some embodiments, the selected network link is the same network link selected in process 250 .
At the process 360 , the network switching unit may deactivate the network link from use by the LAG. According to some embodiments, the network link may be removed from consideration by a LAG hashing algorithm used to select from among the network links associated with the LAG.
At the process 370 , the network switching unit may reduce power provided to the network link. According to some embodiments, the network switching unit may reduce some power or remove all power to the network link. According to some embodiments, the network switching unit may reduce or remove power from a communication port (e.g., one of the communication ports 151 - 153 and/or 131 - 133 ) corresponding to the network link. According to some embodiments, the network switching unit may also reduce or remove power from other circuitry associated with the communication port and/or the network link.
As discussed above and further emphasized here, FIG. 3 is merely an example, which should not unduly limit the scope of the claims. One of ordinary skill in the art would recognize many variations, alternatives, and modifications. According to some embodiments, upon completion of the process 370 , the method 300 may return to process 310 to wait for another network link deactivation request. According to some embodiments, upon completion of the process 370 , the method 300 may switch to process 210 of method 200 to detect whether network conditions are suitable for reducing power consumption on one of the network switching unit's LAGs.
FIG. 4 is a simplified diagram of a method 400 of activating a network link in a network switching unit according to some embodiments. As shown in FIG. 4 , the method 400 includes a process 410 for detecting an end of power conservation conditions, a process 420 for requesting network link activation, a process 430 for receiving a response to the request, a process 440 for determining whether the request was confirmed, a process 450 for negotiating a network link to activate, a process 460 for returning the network link power, and a process 470 for activating the network link for use by a LAG. According to certain embodiments, the method 400 of activating a network link in a network switching unit can be performed using variations among the processes 410 - 470 as would be recognized by one of ordinary skill in the art. According to some embodiments, the process 430 is optional and may be omitted. In some embodiments, one or more of the processes 410 - 470 may be implemented, at least in part, in the form of executable code stored on non-transient, tangible, machine readable media that when run by one or more processors in one or more network switching units (e.g., the network switching units 110 and/or 120 ) may cause the one or more processors to perform one or more of the processes 410 - 470 .
At the process 410 , a network switching unit (e.g., the network switching unit 110 and/or 120 ) may detect an end of power conservation conditions. According to some embodiments, the process 410 may only occur when one or more of the network links (e.g., the network links 141 - 143 ) of a LAG (e.g., the LAG 161 and/or 162 ) are deactivated. In some embodiments, the one or more network links may have been deactivated by the method 200 and/or the method 300 . According to some embodiments, the end of power conservation conditions may indicate that network conditions suggest that additional network links should be activated in the LAG. According to some embodiments, the end of power conservation conditions may occur when a utilization of the LAG rises above a maximum utilization threshold for a period of time. In some embodiments, the maximum utilization threshold may be 80% or higher. In some embodiments, the maximum utilization threshold may be 60% or higher. In some embodiments, the maximum utilization threshold may be set as part of the configuration of the network switching unit. In some embodiments, the maximum utilization threshold may be set using a configuration utility. In some embodiments, the maximum utilization threshold may be stored in one or more memory devices (e.g., ROM, RAM, PROM, EPROM, FLASH-EPROM, and/or any other memory chip or cartridge) coupled to the network switching unit. In some embodiments, the maximum utilization threshold may be dynamic based on a time of day and/or other network settings and/or conditions. In some embodiments, the period of time may be as short as a second or less. In some embodiments, the period of time may be as short as a minute or less. In some embodiments, the period of time may be 5-10 minutes or more in length. In some embodiments, the period of time may be set as part of the configuration of the network switching unit. In some embodiments, the period of time may be set using a configuration utility. In some embodiments, the period of time may be stored in one or more memory devices (e.g., ROM, RAM, PROM, EPROM, FLASH-EPROM, and/or any other memory chip or cartridge) coupled to the network switching unit. In some embodiments, the period of time may be dynamic based on a time of day and/or other network settings and/or conditions.
According to some embodiments, the end of power conservation conditions may occur when a temperature of the network switching unit drops below a minimum temperature threshold. In some embodiments, the minimum temperature threshold may be 100 degrees centigrade or lower. In some embodiments, the minimum temperature threshold may be 65 degrees centigrade or lower. In some embodiments, the minimum temperature threshold may be 40 degrees centigrade or higher. In some embodiments, the minimum temperature threshold may be set as part of the configuration of the network switching unit. In some embodiments, the minimum temperature threshold may be set using a configuration utility. In some embodiments, the minimum temperature threshold may be stored in one or more memory devices (e.g., ROM, RAM, PROM, EPROM, FLASH-EPROM, and/or any other memory chip or cartridge) coupled to the network switching unit. In some embodiments, the minimum temperature threshold may be dynamic based on a time of day and/or other network settings and/or conditions.
According to some embodiments, the end of power conservation conditions may occur based on a time of day.
According to some embodiments, the end of power conservation conditions may occur based on one or more of the factors described above. In some embodiments, any logical and/or temporal combination of the one or more factors may be considered.
At the process 420 , the network switching unit makes a request for link activation. According to some embodiments, the network switching unit may select a LAG (e.g., the LAG of process 410 whose utilization is above the maximum utilization threshold). In some embodiments, the network switching unit may send a network link activation message to a neighboring network switching unit (e.g., the network switching unit 120 and/or 110 ) using one of the network links (e.g., the network links 140 - 143 ) in the LAG. In some embodiments, the link activation message may ask the neighboring network switching unit whether it is willing to activate one of their shared network links.
At the optional process 430 , the network switching unit receives a response to the link activation request. According to some embodiments, the network switching unit may receive a response message on one of the network links in the LAG. In some embodiments, the response message may include information indicating whether the neighboring network switching unit is willing to activate one of their shared network links.
At the process 440 , the network switching unit may determine whether the network link activation request is confirmed. According to some embodiments, the network switching unit examines the response message. According to some embodiments, the network activation request may not be confirmed when no response message is received. In some embodiments, the network deactivation request may not be confirmed when a response message is not received during a timeout period following the making of the activation request. In some embodiments, the timeout period is several milliseconds. In some embodiments, the timeout period is a second or longer. In some embodiments, the timeout period may be set as part of the configuration of the network switching unit. In some embodiments, the timeout period may be set using a configuration utility. In some embodiments, the timeout period may be stored in one or more memory devices (e.g., ROM, RAM, PROM, EPROM, FLASH-EPROM, and/or any other memory chip or cartridge) coupled to the network switching unit. In some embodiments, the timeout period may be dynamic based on a time of day and/or other network settings and/or conditions. If the network switching unit determines that the network link activation request has not been confirmed, the method 400 returns to process 410 .
At the process 450 , the network switching unit and the neighboring network switching unit may negotiate which network link should be activated. According to some embodiments, the network link is selected based on a mutually agreed upon criteria. In some embodiments, the network link, from among the deactivated network links, with a largest ID number is selected. In some embodiments, the network link, from among the deactivated network links, with a smallest ID number is selected. According to some embodiments, the network switching unit and the neighboring switching unit may exchange one or more negotiation messages to determine the network link to activate. According to some embodiments, when only one network link in the LAG is deactivated, it may be selected by default.
At the process 460 , the network switching unit may return power to the network link. According to some embodiments, the network switching unit may return power to a communication port (e.g., one of the communication ports 131 - 133 and/or 151 - 153 ) corresponding to the network link. According to some embodiments, the network switching unit may also return power to other circuitry associated with the communication port and/or the network link.
At the process 470 , the network switching unit may activate the network link for use by the LAG. According to some embodiments, the network link may be added to consideration by a LAG hashing algorithm used to select from among the network links associated with the LAG.
As discussed above and further emphasized here, FIG. 4 is merely an example, which should not unduly limit the scope of the claims. One of ordinary skill in the art would recognize many variations, alternatives, and modifications. According to some embodiments, upon completion of the process 470 , the method 400 may return to process 410 to determine whether one or more additional network links may be activated. According to some embodiments, upon completion of the process 470 , the method may switch to method 200 and/or 300 when a reduction in power consumption is desired.
FIG. 5 is a simplified diagram of a method 500 of activating a network link in a network switching unit according to some embodiments. As shown in FIG. 5 , the method 500 includes a process 510 for receiving a network link activation request, a process 520 for determining whether activation of a network link is acceptable, a process 530 for denying the request, a process 540 for confirming the request, a process 550 for negotiating a network link to activate, a process 560 for returning the network link power, and a process 570 for activating the network link for use by a LAG. According to certain embodiments, the method 500 of reducing power consumption in a network switching unit can be performed using variations among the processes 510 - 570 as would be recognized by one of ordinary skill in the art. According to some embodiments, the process 530 is optional and may be omitted. In some embodiments, one or more of the processes 510 - 570 may be implemented, at least in part, in the form of executable code stored on non-transient, tangible, machine readable media that when run by one or more processors in one or more network switching units (e.g., the network switching units 110 and/or 120 ) may cause the one or more processors to perform one or more of the processes 510 - 570 .
At the process 510 , a network switching unit (e.g., the network switching unit 110 and/or 120 ) may receive a network link activation request. In some embodiments, the network link activation request may be the network link activation request from process 420 . In some embodiments, the network link activation request may be in the form of a from a network link activation message sent by a neighboring network switching unit (e.g., the network switching unit 120 and/or 110 ) using one of the network links (e.g., the network links 140 - 143 ) in a LAG (e.g., the LAG 162 and/or 161 ).
At the process 520 , the network switching unit determines whether activation of a network link is acceptable. According to some embodiments, the network switching unit may make its determination using one or more factors similar to the one or more factors used in the process 410 to detect whether network conditions are suitable for activating a network link. In some embodiments, the network switching unit may consider a utilization of the LAG. In some embodiments, the network switching unit may consider a temperature of the network switching unit. In some embodiments, the network switching unit may consider a time of day. In some embodiments, any logical and/or temporal combination of the one or more factors may be considered. According to some embodiments, the network switching unit may have an elevated temperature that does not permit activation of a network link. If the network switching unit determines that activation of a network link is not acceptable, the method 500 moves to process 530 . Otherwise, the method 500 moves to process 540 .
At the optional process 530 , the network switching unit denies the activation request. According to some embodiments, the network switching unit may send a response message on one of the network links in the LAG. In some embodiments, the response message may include information indicating that the network switching unit is not willing to activate one of its network links. In some embodiments, the response message may be the response received by the neighboring network switching device in process 430 .
At the process 540 , the network switching unit confirms the activation request. According to some embodiments, the network switching unit may send a response message on one of the network links in the LAG. In some embodiments, the response message may include information indicating that the network switching unit is willing to activate one of its network links. In some embodiments, the response message may be the response received by the neighboring network switching device in process 430 .
At the process 550 , the network switching unit and the neighboring network switching unit may negotiate which network link should be activated. According to some embodiments, the network link is selected based on a mutually agreed upon criteria. In some embodiments, the network link, from among the deactivated network links, with a largest ID number is selected. In some embodiments, the network link, from among the deactivated network links, with a smallest ID number is selected. According to some embodiments, the network switching unit and the neighboring switching unit may exchange one or more negotiation messages to determine the network link to activate. According to some embodiments, when only one network link in the LAG is deactivated, it may be selected by default. According to some embodiments, the selected network link is the same network link selected in process 450 .
At the process 560 , the network switching unit may return power to the network link. According to some embodiments, the network switching unit may return power to a communication port (e.g., one of the communication ports 151 - 153 and/or 131 - 133 ) corresponding to the network link. According to some embodiments, the network switching unit may also return power to other circuitry associated with the communication port and/or the network link.
At the process 570 , the network switching unit may activate the network link for use by the LAG. According to some embodiments, the network link may be added to consideration by a LAG hashing algorithm used to select from among the network links associated with the LAG.
As discussed above and further emphasized here, FIG. 5 is merely an example, which should not unduly limit the scope of the claims. One of ordinary skill in the art would recognize many variations, alternatives, and modifications. According to some embodiments, upon completion of the process 570 , the method 500 may return to process 510 to wait for another network link activation request. According to some embodiments, upon completion of the process 570 , the method 500 may switch to process 410 of method 400 to detect whether network conditions are suitable for activating another network link. According to some embodiments, upon completion of the process 570 , the method may switch to method 200 and/or 300 when a reduction in power consumption is desired.
According to certain embodiments the methods 200 , 300 , 400 , and/or 500 may be implemented using an extension to the Link Aggregation Control Protocol (LACP) as described in the IEEE 802.1AX standard. FIG. 6 is a simplified diagram of an extension 600 to an actor and a partner state of a LACP data unit (LACPDU) according to some embodiments. As shown in FIG. 6 , the extension 600 to the actor and/or partner state includes a conserve power bit 610 with the remaining bits 620 being reserved for other uses. The conserve power bit 610 may be used to designate whether a network switching unit (e.g., the actor or the partner) is willing to activate and/or deactivate a network link. According to some embodiments, a conserve power value of the conserve power bit 610 may indicate a willingness to deactivate a network link and a normal power value of the conserve power bit 610 may indicate an unwillingness to deactivate a network link. In some embodiments, the conserve power value may be a logic 1 and the normal power value may be a logic 0.
According to some embodiments, the extension 600 to the actor and partner state may be used in the method 200 . At the process 220 , the network switching unit (i.e., the actor) may format and send a LACPDU with the actor state extension 600 containing the conserve power value for the conserve power bit 610 . By sending the LACPDU with the conserve power bit 610 set to the conserve power value, the network switching unit indicates that it desires a reduction in power. At the process 230 , the network switching unit may receive a LACPDU from the neighboring network switching unit (i.e., the partner) with the partner state extension 600 . When the partner state extension 600 includes the conserve power value for the conserve power bit 610 , the network switching unit may determine that the deactivation request is confirmed during process 240 . When the partner state extension 600 includes the normal power value for the conserve power bit 610 , the network switching unit may determine that the deactivation request is not confirmed during process 240 . At the process 260 , the network switching unit may deactivate the network link from use by the LAG by changing a state of the selected network link and/or the corresponding communication port from NORMAL to STANDBY.
According to some embodiments, the extension 600 to the actor and partner state may be used in the method 300 . At the process 310 , the network switching unit (i.e., the partner) may receive a LACPDU from the neighboring network switching unit (i.e., the actor) with the actor state extension 600 containing the conserve power value for the conserve power bit 610 , thus making a link deactivation request. The network switching unit may respond to the link deactivation request by responding with a LACPDU containing a partner state extension 600 . By sending the conserve power value as the conserve power bit 610 , the network switching unit may confirm the link deactivation request in process 340 . By sending the normal power value as the conserve power bit 610 , the network switching unit may deny the link deactivation request in process 330 . At the process 360 , the network switching unit may deactivate the network link from use by the LAG by changing the state of the selected network link and/or the corresponding communication port from NORMAL to STANDBY.
According to some embodiments, the extension 600 to the actor and partner state may be used in the method 400 . At the process 420 , the network switching unit (i.e., the actor) may format and send a LACPDU with the actor state extension 600 containing the normal power value for the conserve power bit 610 . By sending the LACPDU with the conserve power bit 610 set to the normal power value, the network switching unit indicates that it desires to activate a network link. At the process 430 , the network switching unit may receive a LACPDU from the neighboring network switching unit (i.e., the partner) with the partner state extension 600 . When the partner state extension 600 includes the conserve power value for the conserve power bit 610 , the network switching unit may determine that the activation request is not confirmed during process 440 . When the partner state extension 600 includes the normal power value for the conserve power bit 610 , the network switching unit may determine that the activation request is confirmed during process 440 . At the process 470 , the network switching unit may activate the network link from use by the LAG by changing a state of the selected network link and/or the corresponding communication port from STANDBY to NORMAL.
According to some embodiments, the extension 600 to the actor and partner state may be used in the method 500 . At the process 510 , the network switching unit (i.e., the partner) may receive a LACPDU from the neighboring network switching unit (i.e., the actor) with the actor state extension 600 containing the normal power value for the conserve power bit 610 , thus making a link activation request. The network switching unit may respond to the link activation request by responding with a LACPDU containing a partner state extension 600 . By sending the conserve power value as the conserve power bit 610 , the network switching unit may deny the link activation request in process 530 . By sending the normal power value as the conserve power bit 610 , the network switching unit may confirm the link activation request in process 540 . At the process 570 , the network switching unit may activate the network link from use by the LAG by changing a state of the selected network link and/or the corresponding communication port from STANDBY to NORMAL.
Some embodiments of network switching units 110 and/or 120 may include non-transient, tangible, machine readable media that include executable code that when run by one or more processors may cause the one or more processors to perform the processes of methods 200 , 300 , 400 , and/or 500 as described above. Some common forms of machine readable media that may include the processes of methods 200 , 300 , 400 , and/or 500 are, for example, floppy disk, flexible disk, hard disk, magnetic tape, any other magnetic medium, CD-ROM, any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes, RAM, PROM, EPROM, FLASH-EPROM, any other memory chip or cartridge, and/or any other medium from which a processor or computer is adapted to read.
Although illustrative embodiments have been shown and described, a wide range of modification, change and substitution is contemplated in the foregoing disclosure and in some instances, some features of the embodiments may be employed without a corresponding use of other features. One of ordinary skill in the art would recognize many variations, alternatives, and modifications. Thus, the scope of the invention should be limited only by the following claims, and it is appropriate that the claims be construed broadly and in a manner consistent with the scope of the embodiments disclosed herein.
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A system and method of reducing power consumption in a network switching unit includes detecting whether conditions are suitable for reducing power consumption in a first network switching unit. The first network switching unit includes a link aggregation group (LAG) and a plurality of communication ports, each communication port configured to couple the first network switching unit to a second network switching unit using a corresponding network link selected from a plurality of network links, and wherein the plurality of network links are assigned to the LAG. The system and method further includes requesting network link deactivation by sending a link deactivation request to the second network switching unit, determining whether the link deactivation request is approved, determining a first network link selected from the plurality of network links to deactivate, deactivating the first network link from use by the LAG, and reducing power supplied to the first network link.
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BACKGROUND
This invention relates to the recovery of gas from coal seams, and more particularly to a new method of completing wells used for the demethanization of coal seams.
Many different methods for completing wells used for demethanization of coal seams have been employed including: open hole, open hole with abrasijet scoring, open hole with fracturing, slotted liner, cased hole with perforation only, and cased hole with fracture stimulation. Different fracturing techniques have also been used including gelled water, nitrogen foam with and without proppant, fresh water with and without proppant, and fresh water with friction reducing organic polymer with proppant.
The main problem with most coal bed completion techniques, is the migrating coal fines. This frequently leads to plugging or impairment behind perforated casings or slotted liners or in filling the rathole and covering the perforations, which leads to a severely decreased flow of gas.
OBJECT AND SUMMARY OF THE INVENTION
It is therefore the object of the present invention to provide a new method of well completion which would substantially prevent coal fines from blocking the perforations in the well casing.
The method, in accordance with the present invention, comprises the steps of providing perforations in the casing of the well above and/or below the coal seam, and hydraulically fracturing the coal seam through the perforations in the casing.
The perforations are preferably made at a distance up to 5 meters from the coal seam.
Once the hydraulic fracture is initiated with a suitable fluid, a fine grained proppant, such as sand or high strength ceramic grains, may be used to stimulate gas flow.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be disclosed, by way of example, with reference to the accompanying drawings in which:
FIGS. 1 and 2 illustrate a conventional method of completing a production well used for the recovery of gas from a coal seam;
FIG. 3 illustrates a method of completing a production well in accordance with the present invention; and
FIG. 4 illustrates a model of hydraulic fracturing initiated through perforations in the well casing above the level of the coal seam.
DETAILED DESCRIPTION
Referring to FIG. 1, there is shown a portion of a well 10 drilled through earth formations adjacent a coal seam 12. A casing 14 is cemented in place in the well and provided with perforations 16 opposite the coal seam 12. The casing is blocked below the coal seam by a plug 18.
Of the major problems that inhibit successful completions in coal seams, the most difficult to solve has been the prevention of impairment due to migration of coal fines 20 which accumulate near the perforations 16 during withdrawal of gas from the coal seam. Even in cased holes that have been hydraulically fractured through the perforations opposite the coal seam, the fines tend to plug the propped fracture near the perforations or the perforations themselves. Sometimes enough fines flow through the perforations to eventually plug the casing over and above the perforated interval as shown in FIG. 2 of the drawings. In any of the above cases, the result is severe restriction to the flow of gas.
FIG. 3 of the drawings shows the method of the present invention to solve the above problem. This is accomplished by avoiding placing any perforations or slots through the casing opposite the coal seam. Instead, the perforations or slots are introduced above and/or below the coal seam. By removing the focal point for fines migrations away from the coal seam and introducing a broad area fine mesh "filter", the fines do not have an opportunity to impair the gas flow. The distance of the nearest perforation to the coal seam is not critical, but in a typical completion might be anywhere up to 5 meters. The number and gross interval of perforations may vary but a preferred configuration might be a helical pattern of six to twelve perforations per meter for two to five meters above and below the coal seam. Then the "filters" may be emplaced with a fluid that is pressured to exceed the fracture gradient of the formation opposite the perforations. After the formation fracture is initiated with the fluid, a fine grained proppant, such as sand or high strength ceramic grains is introduced as in conventional hydraulic fracturing as shown in FIG. 3. Pressure is then quickly released on the fracturing fluid to insure closure of the formation onto the proppant before the proppant has a chance to settle.
FIG. 4 of the drawings shows a model of hydraulic fracture initiated through perforations 22 located in a sandstone formation 24 above a coal seam 26 at about 10,000 feet below the earth surface. The fracture grows initially in the sandstone formation 24 and when the fracture intersects the coal seam, the subsequent growth is predominantly in the coal seam 26. As the fracture grows, the pressure will again rise to a level sufficient to propagate the fracture in both formations. However, the length of the fracture in the sandstone formation will be considerably less than for the coal seam. There is little propagation in the shale formation 28. The fracture thus preferentially propagates within the coal seam while allowing ample filtration area around the perforated interval.
With such a technique, coal fines may be screened out over a large area as shown in FIG. 3 rather than focused at perforations or flow channels opposite the coal seam as shown in FIGS. 1 and 2. With this new technique, even if one preferential flow path started to plug there would be an almost unlimited number of alternate paths within the "filter" through which the gas could flow.
Additional benefits for gas flow may follow if the beds surrounding the coal seam were gas charged tight sands. The technique in accordance with the present invention is especially suitable for multiple seams of coal within a gross interval. It would not matter whether the coal seams were thick or thin.
Although FIG. 4 shows a model of hydraulic fracture wherein perforations are located above the coal seam, similar results would be obtained if perforations were located above and below the coal seam. The only changes would be short length fractures in both the sandstone and shale formations 24 and 28 instead of just the sandstone formation 24.
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A method of completing a production well for the recovery of gas from a coal seam is disclosed. The well is of the type having a casing cemented in the well and the method comprises the steps of providing perforations in the casing above and/or below the coal seam, and hydraulically fracturing the coal seam through the perforations in the casing.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority as a continuation of U.S. patent application Ser. No. 11/801,468, filed on May 9, 2007, for “Systems and Methods for Synchronizing Operations Among a Plurality of Independently Clocked Digital Data Processing Devices Without a Voltage Controlled Crystal Oscillator,” which is incorporated herein by reference, which is a continuation-in-part application which claims the benefit and priority of U.S. patent application Ser. No. 10/816,217 filed on Apr. 1, 2004 for “System and Method For Synchronizing Operations Among a Plurality of Independently Clocked Digital Data Processing Devices,” which is incorporated herein by reference, which claims the benefit and priority of U.S. Provisional Patent Application Ser. No. 60/490,768 filed on Jul. 28, 2003 for “Method For Synchronizing Audio Playback Between Multiple Networked Devices,” which is incorporated herein by reference; and the present application incorporates by reference U.S. Provisional Patent Application Ser. No. 60/860,964 filed on Nov. 22, 2006 and U.S. Provisional Patent Application Ser. No. 60/876,455 filed on Dec. 20, 2006, both for “Systems and Methods for Synchronizing Operations Among a Plurality of Independently Clocked Digital Data Processing Devices that Independently Source Digital Data.”
FIELD OF THE INVENTION
[0002] The present invention relates generally to digital content, and more particularly, to systems and methods for synchronizing operations among a plurality of independently clocked digital data processing devices without a voltage controlled crystal oscillator.
DESCRIPTION OF RELATED ART
[0003] Conventionally, playing the same digital content over multiple audio and/or audiovisual reproduction devices simultaneously or in synchrony is limited by the inherent differences in the frequencies or clock rates of the crystal oscillators influencing the rates in which the digital content is converted to analog content for playing over the respective audio and/or audiovisual reproduction devices. Previous approaches that solve this problem require expensive hardware and/or circuitry, which also requires additional space within the audio and/or audiovisual reproduction device. There is thus a need for systems and methods for synchronizing operations among a plurality of independently clocked digital data processing devices without a voltage controlled crystal oscillator.
SUMMARY OF THE INVENTION
[0004] Exemplary systems and methods are provided that include a distribution device that maintains a clock rate and distributes a series of tasks to a group of execution devices (or synchrony group). Each task has a plurality of samples per frame associated with a time stamp indicating when the task is to be executed. An execution device executes the series of tasks at the times indicated and adjusts the number of samples per frame in relation to the clock rate maintained by the distribution device. The synchrony group may also be configured to adjust samples per frame in relation to a clock rate maintained by the distribution device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 illustrates an exemplary networked system;
[0006] FIG. 2 illustrates a functional block diagram of a synchrony group utilizing a plurality of zone players formed within the exemplary networked system depicted in FIG. 1 ;
[0007] FIG. 3 illustrates a functional block diagram of a zone player for use in the networked system depicted in FIG. 1 ; and
[0008] FIG. 4 illustrates an exemplary digital framing methodology.
DETAILED DESCRIPTION
[0009] Referring to FIG. 1 , an exemplary network audio system 10 is shown in which various embodiments of the invention may be practiced. Although the term “audio” is used in connection with the exemplary network audio system 10 , it will readily be appreciated that the herein described systems and methods may be employed with other forms of digital data, including visual and/or audiovisual digital data.
[0010] The exemplary network audio system 10 includes at least one zone player 11 , interconnected by a local network 12 , all of which may operate under the control of one or more user interface modules identified by reference numeral 13 . The zone player 11 is sometimes referred to as a digital data processing device. One or more of the zone players 11 may also be connected to one or more audio information sources, which will generally be identified herein by reference numeral 14 , and/or connected to one or more audio reproduction devices, which will generally be identified by reference numeral 15 . It will be appreciated that the number of audio information sources may vary as among the various zone players 11 , and some zone players may not have any audio information sources connected thereto.
[0011] A plurality of zone players 11 associated with a network audio system 10 may be distributed throughout an establishment, such as residence, an office complex, a hotel, a conference hall, an amphitheater, auditorium, or other types of establishments as will be apparent to those skilled in the art. For example, a zone player 11 and its associated audio information source(s) and audio reproduction device(s) may be located in a living room, another zone player may be located in a kitchen, another zone player may be located in a dining room, and other zone players may be located in bedrooms, to selectively provide entertainment in those rooms. The audio information sources 14 may be any of a number of types of conventional sources of audio information, including, for example, compact disc (“CD”) players, AM and/or FM radio receivers, analog or digital tape cassette players, analog record turntables and the like. In addition, the audio information sources 14 may comprise digital audio files stored locally on, for example, personal computers (PCs), personal digital assistants (PDAs), or similar devices capable of storing digital information in volatile or non-volatile form. The audio information sources 14 may also comprise an interface to a wide area network such as the Internet, or any other source of audio information, or an interface to radio services delivered over, for example, satellite. Audio information obtained over the wide area network may comprise, for example, streaming digital audio information such as Internet radio, digital audio files stored on servers, and other types of audio information and sources as will be appreciated by those skilled in the art.
[0012] Generally, the audio information sources 14 provide audio information associated with audio programs to the zone players for playback. A zone player that receives audio information from an audio information source 14 that is connected thereto may provide playback and/or forward the audio information, along with playback timing information, over the local network 12 to other zone players for playback. Users, using user interface module 13 , may also enable different groupings or sets of zone players to provide audio playback of different audio programs synchronously.
[0013] Referring to FIG. 2 , an exemplary group of execution devices (or “synchrony group”) 20 according to one embodiment of the invention is shown. The exemplary synchrony group 20 comprises synchrony group member devices or member devices including a master execution device 21 and zero or more slave devices 22 ( 1 ) through 22 (G) (generally identified by reference numeral 22 ( g )), all of which synchronously play an audio program provided by an audio information channel device 23 . The audio information channel device 23 is sometimes referred to as a task source or a task distribution device. Each master execution device 21 , slave device 22 ( g ), and/or audio information channel device 23 may utilize a zone player 11 as depicted in FIG. 1 . The zone player 11 may function as an audio information channel device 23 , a master execution device 21 , or a slave device 22 ( g ) for the synchrony group 20 . The audio information channel device 23 may obtain audio information for the audio program from an audio information source 14 , add playback timing information, and transmit the combined audio and playback timing information to the master execution device 21 and slave devices 22 ( g ) over local network 12 ( FIG. 1 ) for playback. The playback timing information that is provided with the audio information, together with clock timing information provided by the audio information channel device 23 to the various devices 21 and 22 ( g ), enables the master execution device 21 and slave devices 22 ( g ) of the synchrony group 20 to play the audio information simultaneously.
[0014] The master execution device 21 and the slave devices 22 ( g ) receive the audio and playback timing information, as well as the clock timing information, that are provided by the audio information channel device 23 , and play back the audio program defined by the audio information. The master execution device 21 also communicates with the user interface module 13 , controls the operations of the slave devices 22 ( g ) in the synchrony group 20 , and controls the operations of the audio information channel device 23 that provides the audio and playback timing information for the synchrony group 20 . Generally, the initial master execution device 21 for the synchrony group will be the first zone player 11 that a user wishes to play an audio program. However, the master execution device 21 may be migrated from a first zone player to a second zone player, which preferably will be a zone player that is currently operating as a slave device 22 ( g ) in the synchrony group.
[0015] In addition, under certain circumstances, the audio information channel device 23 may be migrated from one zone player to another zone player, which also may be a zone player that is currently operating as a member of the synchrony group 20 . It will be appreciated that the zone player that operates as the master execution device 21 may be migrated to another zone player independently of the migration of the audio information channel device 23 . For example, if a first zone player is operating as both the master execution device 21 and the audio information channel device 23 for a synchrony group 20 , the function of the master execution device 21 may be migrated to a second zone player while the first zone player is still operating as the audio information channel device 23 . Similarly, if a first zone player is operating as both the master execution device 21 and the audio information channel device 23 for a synchrony group 20 , the source function of the audio information channel device 23 may be migrated to a second zone player while the first zone player is still operating as the master execution device 21 . In addition, if a first zone player is operating as both the master execution device 21 and the audio information channel device 23 for a synchrony group 20 , the master execution device 21 may be migrated to a second zone player and the audio information channel device may be migrated to a third zone player.
[0016] The master execution device 21 receives control information from the user interface module 13 for controlling the synchrony group 20 and provides status information indicating the operational status of the synchrony group 20 to the user interface module 13 . Generally, the control information from the user interface module 13 causes the master execution device 21 to enable the audio information channel device 23 to provide audio and playback timing information to the synchrony group, allowing the devices 21 and 22 ( g ) that are members of the synchrony group 20 to play the audio program synchronously. In addition, the control information from the user interface module 13 causes the master execution device 21 to enable other zone players to join the synchrony group as slave devices 22 ( g ) and/or to cause slave devices 22 ( g ) to disengage from the synchrony group. Control information from the user interface module 13 may also cause the zone player 11 that is currently operating as the master execution device 21 to disengage from the synchrony group, but prior to doing so, that zone player will cause the function of the master execution device 21 to transfer from that zone player 11 to a second zone player, preferably to a second zone player that is currently a slave device 22 ( g ) in the synchrony group 20 . The control information from the user interface module 13 may also cause the master execution device 21 to adjust its playback volume and/or to enable individual ones of the various slave devices 22 ( g ) to adjust their playback volumes. In addition, the control information from the user interface module 13 may cause the synchrony group 20 to terminate playing of a current track of the audio program and skip to the next track, and to re-order tracks in a play list of tracks defining the audio program that are to be played by the synchrony group 20 . The status information that the master execution device 21 may provide to the user interface module 13 may include such information as a name or other identifier for the track of an audio work that is currently being played, the names or other identifiers for upcoming tracks, the identifier of the zone player 11 that is currently operating as the master execution device 21 , and identifiers of the zone players that are currently operating as slave devices 22 ( g ). In one embodiment, the user interface module 13 may include a display that can display the status information to the user. It will be appreciated that the zone player 11 that is operating as the audio information channel device 23 for one synchrony group may also comprise the master execution device 21 or any of the slave devices 22 ( g ) in another synchrony group. This may occur if, for example, the audio information source that is to provide the audio information that is to be played by the one synchrony group is connected to a zone player also being utilized as the master execution device or a slave device for the other synchrony group.
[0017] Referring to FIG. 3 , a functional block diagram of an exemplary zone player 11 constructed in accordance with one embodiment of the invention is shown. The exemplary zone player 11 includes an audio information source interface 30 , an audio information buffer 31 , a playback scheduler 32 , a digital to analog converter 33 , an audio amplifier 35 , an audio reproduction device interface 36 , a network communications manager 40 , a network interface 41 , and a control module 42 . In an alternative system and method, the exemplary zone player 11 may not include the audio amplifier 35 . In a further embodiment, the zone player 11 includes and/or forms part of the audio reproduction device 15 . The zone player 11 also has a device clock 43 that provides timing signals that control the general operations of the zone player 11 . In addition, the zone player 11 includes a user interface module interface 44 that can receive control signals from the user interface module 13 ( FIGS. 1 and 2 ) for controlling operations of the zone player 11 , and provides status information to the user interface module 13 .
[0018] Generally, the audio information buffer 31 buffers audio information, in digital form, along with playback timing information. If the zone player 11 is operating as the audio information channel device 23 ( FIG. 2 ) for a synchrony group 20 , the information that is buffered in the audio information buffer 31 may include the audio and playback timing information that will be provided to the devices 21 and 22 ( g ) in the synchrony group 20 . If the zone player 11 is operating as the master execution device 21 or a slave device 22 ( g ) for a synchrony group ( 20 ), the information that is buffered in the audio information buffer 31 may include the audio and playback timing information that the zone player 11 is to play. The audio information buffer 31 may receive audio and playback timing information from two sources, namely, the audio information source interface 30 and the network communications manager 40 . In particular, if the zone player 11 is operating as the audio information channel device 23 for a synchrony group 20 , and if the audio information source is a source 14 connected to the zone player 11 , the audio information buffer 31 may receive and buffer audio and playback timing information from the audio information source interface 30 . Alternatively, if the zone player 11 is operating as the audio information channel device 23 for a synchrony group 20 , and if the audio information source is a source 14 connected to the network 12 , or a source available over a wide area network, the audio information buffer 31 may receive and buffer audio and playback timing information from the network communications manager 40 . However, if the zone player 11 is operating as the master execution device 21 or a slave device 22 ( g ) in a synchrony group 20 , and if the zone player 11 is not also the audio information channel device 23 providing audio and playback timing information for the synchrony group 20 , the audio information buffer 31 may receive and buffer audio and playback timing information from the network communications manager 40 . It will be appreciated that, if the zone player 11 is not a member of the synchrony group, the zone player 11 may not play this buffered audio and playback timing information.
[0019] According to some embodiments, the audio information source interface 30 connects to the audio information source(s) 14 associated with the zone player 11 . While the zone player 11 is operating as the audio information channel device 23 for a synchrony group 20 , and if the audio information is to be provided by a source 14 connected to the zone player 11 , the audio information source interface 30 will selectively receive audio information from one of the audio information source(s) 14 to which the zone player is connected and store the audio information in the audio information buffer 21 . If the audio information from the selected audio information source 14 is in analog form, the audio information source interface 30 will convert it to digital form. The selection of the audio information source 14 from which the audio information source interface 30 receives audio information is under the control of the control module 42 , which, in turn, receives control information from the user interface module through the user interface module interface 44 . The audio information source interface 30 adds playback timing information to the digital audio information and buffers the combined audio and playback timing information in the audio information buffer 21 . More specifically, the audio information source interface 30 receives audio information from an audio information source 14 , converts it to digital form if necessary, and buffers it along with playback timing information in the audio information buffer 21 . In addition, the audio information source interface 30 may also provide formatting and scheduling information for the digital audio information, whether as received from the selected audio information source 14 or as converted from an analog audio information source. The formatting and scheduling information will control not only playback by the zone player 11 itself, but will also enable other zone players that may be in a synchrony group for which the zone player 11 is the master execution device to play the audio program associated with the audio information in synchrony with the zone player 11 .
[0020] In one particular embodiment, the audio information source interface 30 divides the audio information associated with an audio work into a series of frames, with each frame comprising digital audio information for a predetermined period of time. As used herein, an audio track may comprise any unit of audio information that is to be played without interruption, or a series of one or more audio tracks that are to be played in succession. It will be appreciated that the tracks comprising the audio program may also be played without interruption, or alternatively playback between tracks may be interrupted by a selected time interval.
[0021] FIG. 4 depicts an illustrative framing strategy used in connection with one system and method of the invention for a digital audio stream comprising an audio work. A framed digital audio stream 50 comprises a sequence of frames 51 ( 1 ) through 51 (F) (generally identified by reference numeral 51 ( f )). Here, “(f)” may represent a generic sequence number for any particular frame ( 51 ), with the actual sequence numbers ranging from “(1)” to “(F).” Each frame 51 ( f ), in turn, comprises a series of audio samples 52 ( f )( 1 ) through 52 ( f )(S) (generally identified by reference numeral 52 ( f )(s)) of the audio track. The number of audio samples 52 ( f )(s) may differ in each frame 51 ( f ). Associated with each frame 51 ( f ) is a header 55 ( f ) that includes a number of fields for storing other information that is useful in controlling playback of the audio samples in the respective frame 51 ( f ). In particular, the header 55 ( f ) associated with a frame 51 ( f ) includes a frame sequence number field 56 , an encoding type field 57 , a sampling rate information field 58 , a time stamp field 60 , an end of track flag 61 , and a length flag field 62 . The header 55 ( f ) may also include fields for storing other information that is useful in controlling playback.
[0022] Generally, the frame sequence number field 56 receives a number which will generically be the number “f,” from the range 1 through F as above, that identifies the relative position of the frame 51 ( f ) in the sequence of frames containing the digital audio stream 50 . The encoding type field 57 receives a value that identifies the type of encoding and/or compression that has been used in generating the digital audio stream. Conventional encoding or compression schemes include, for example, M3 and WAV encoding and/or compression schemes, although it will be appreciated that other schemes may be provided for as well. The sampling rate information field 58 includes sampling rate information that may indicate the sampling rate relative to the audio information channel device 23 and/or the sampling rate relative to a current inherent, clock rate of a synchrony group member. The condition of the end of work flag 61 indicates whether the frame 51 ( f ) contains the last digital audio samples for the audio track associated with the framed digital audio work 50 . If the frame 51 ( f ) does not contain the audio samples that are associated with the end of the digital audio stream 50 for a respective audio work, the end of work flag will be clear. On the other hand, if the frame 51 ( f ) does contain the audio samples that are associated with the end of the digital audio stream 50 for a respective audio work, the end of work flag 61 will be set. In addition, the length flag field 62 will contain a value that identifies the number of audio samples in the last frame 51 (F) of the audio work 50 . The time stamp field 60 stores a time stamp that identifies the time at which the zone player 11 is to play the respective frame.
[0023] Within each synchrony group member, for each frame of a framed digital audio stream 50 that is buffered in the audio information buffer 21 , the audio information source interface 30 , using timing information from the digital to analog converter clock 34 , may determine a time at which the zone player 11 is to play the respective frame, and will store a time stamp identifying the playback time in the time stamp field 60 . The time stamp associated with each frame is used by the playback scheduler 32 to determine when the portion of the digital audio stream stored in the frame is to be coupled to the digital to analog converter 33 to initiate play back. It will be appreciated that the time stamps that are associated with each of the frames in sequential frames will be such that they will be played back in order, and without an interruption between the sequential frames comprising the digital audio stream 50 . It will further be appreciated that, after a time stamp has been determined for the first frame and stored in frame 51 ( 1 ) of a digital audio stream 50 , the audio information source interface 30 may determine time stamps for the subsequent frames in relation to the number of samples in the respective frames and the current inherent clock rate of the synchrony group member. The time stamps will also preferably be such that frames will be played back after some slight time delay after they have been buffered in the audio information buffer 21 .
[0024] In some embodiments, the zone players 11 are provided with a digital to analog converter clock 34 whose time may be set by an element such as the network communications manager 40 . When a zone player 11 is operating as a member of a synchrony group 20 , its network communications manager 40 may use the various types of timing information that it receives from the audio information channel device 23 to adjust the time value of the synchrony group member's digital to analog converter clock 34 . If the clock's time value is to be adjusted, when the synchrony group member's network communications manager 40 initially receives the current time information from the audio information channel device 23 for the synchrony group 20 , the network communications manager 40 may set the synchrony group member's digital to analog converter clock 34 to the current time value as indicated by the audio information channel device's current time information 23 . The network communications manager 40 may set the digital to analog converter clock 34 to the current time value indicated by the audio information channel device's current time information once, or periodically as it receives the current time information.
[0025] After the network communications manager 40 receives a frame 51 ( f ) from the network interface 41 , it may also obtain, from the digital to analog converter clock 34 , the zone player 11 's current time as indicated by its digital to analog converter clock 34 . The network communications manager 40 may determine a time differential value that is the difference between the slave device's current clock time, as indicated by its digital to analog converter clock 34 , and the audio information channel device's time as indicated by the audio information channel device's clock timing information. Accordingly, if the slave device's current time has a value TS and the audio information channel device's current time, as indicated by the clock timing information, has a value TC, the time differential value ΔT=TS−TC. If the current time of the slave device in the synchrony group 20 , as indicated by its digital to analog converter clock 34 , is ahead of the audio information channel device's clock time, the time differential value will have a positive value. On the other hand, if the slave device's current time is behind the audio information channel device's clock time, the time differential value ΔT will have a negative value. If the zone player 11 obtains clock timing information from the audio information channel device 23 periodically while it is a member of the synchrony group 20 , the network communications manager 40 may generate an updated value for the time differential value ΔT when it receives the clock timing information from the audio information channel device 23 , and may subsequently use the updated time differential value.
[0026] The network communications manager 40 may use the time differential value ΔT that it generates from the audio information channel device timing information and zone player 11 's current time to update the time stamps that will be associated with the digital audio information frames that the zone player 11 receives from the audio information channel device. For each digital audio information frame that is received from the audio information channel device, instead of storing the time stamp that is associated with the frame as received in the message in the audio information buffer 21 , the network communications manager 40 will store the updated time stamp with the digital audio information frame. The updated time stamp is generated in a manner so that, when the zone player 11 , as a member of the synchrony group plays back the digital audio information frame, it will do so in synchrony with other devices in the synchrony group.
[0027] The network communications manager 40 may utilize the updated time stamps associated with respective frames 51 ( f ) to accommodate the current inherent clock rate of the digital to analog converter clock 34 of the synchrony group member. For example, when the synchrony group member's network communications manager 40 receives a first frame 51 ( 1 ) having a time stamp having a time value T, it can generate an updated time value TU, and store the frame 51 ( 1 ) with the updated time value TU in the audio information buffer 31 (e.g., 51 ( 1 )TU). In addition, since both the number of samples in a frame and the current inherent clock rate of the digital to analog converter clock 34 , which determines the rate at which the samples in a frame are to be played by the synchrony group member, are known to the network communications manager 40 , the network communications manager 40 can use that information, along with the time value TU to generate an expected or predicted time value TE for the time stamp of the next frame 51 ( 2 ). After the synchrony group member's network communications manager 40 receives frame 51 ( 2 ), it can generate the updated time value TU for frame 51 ( 2 ) and compare that time value to the time value TE that was predicted for frame 51 ( 2 ). If the two time values do not correspond, or if the difference between them is above a selected threshold level, the clock that is used by the audio information channel device 23 to generate the time stamps is advancing at a different rate than the synchrony group member's digital to analog converter clock 34 , and the network communications manager 40 may adjust the number of samples per frame to accommodate the current inherent clock rate of the digital to analog converter clock 34 of the synchrony group member. If the two time values do correspond (e.g., 51 ( 2 )TE= 51 ( 2 )TU), or the difference is below a threshold level, the time differential value is constant, and the network communications manager 40 need not accommodate the current inherent clock rate of the digital to analog converter clock 34 of the synchrony group member.
[0028] As an example of one way the network communications manager 40 adjusts the number of samples in one or more frames to accommodate the current inherent clock rate of the digital to analog converter clock 34 of a synchrony group member, consider a situation where the clock used by an audio information channel device 23 indicates a sampling rate of 44105 samples per second for the audio information channel device 23 . A synchrony group member with a digital to analog converter clock 34 operating at a current inherent clock rate of 44100 samples per second will require the network communications manager 40 for the synchrony group member to reduce the number of samples in one or more frames by five samples for each one second interval that a particular track(s) comprising one or more frames are being played by the synchrony group member.
[0029] Continuing this example, a second synchrony group member with a digital to analog converter clock 34 operating at a current inherent clock rate of 44110 samples per second will require the network communications manager 40 for the second synchrony group member to increase the number of samples in one or more frames by five samples for each one second interval that a particular track(s) comprising one or more frames is being played by the second synchrony group member. As a result of the independent adjustments taking place within the first and second synchrony group members in relation to their shared audio information channel device 23 , both synchrony group members will be playing the same or nearly the same frame at the same time, despite the differences in their respective current inherent clock rates.
[0030] An information channel device 23 may be configured to periodically receive the respective current inherent clock rates of one or more synchrony group members comprising a synchrony group. Using this information, the audio information channel device 23 performs the requisite adjustments (instead of the respective one or more synchrony group members) and sends one or more tracks to each synchrony group member, wherein the one or more tracks are adjusted to accommodate the current inherent clock rates of the respective synchrony group members. Accordingly, as a result of the multiple adjustments taking place within the audio information channel device 23 with respect to the current inherent clock rates of the one or more synchrony group members, all synchrony group members may play the same or nearly the same frame at the same time, despite the differences in their respective current inherent clock rates.
[0031] The exemplary zone player 11 serving as a synchrony group member may or may not include an audio amplifier 35 ( FIG. 3 ). Further, as described herein, an audio information channel device 23 may perform the requisite sample adjustments or each synchrony group member may perform the requisite sample adjustments. Provided the synchrony group member and/or the audio reproduction device 15 (that is wired or wirelessly associated with the synchrony group member) includes at least one amplifier, regardless of scenario, the audio reproduction device 15 may adapt and maintain as constant a current inherent clock rate of the synchrony group member. Accordingly, the audio reproduction device 15 may play the same or nearly the same frame at the same time as another synchrony group member. This may be advantageous, because some audio reproduction devices 15 may be incapable of making timely clock rate adjustments. Consequently, by adjusting samples per frame, some exemplary systems and methods as described herein may function with audio reproduction devices 15 that would otherwise be incompatible with those systems and methods that include clock rate adjustments for achieving a synchronous performance.
[0032] While various systems and methods have been described above, it should be understood that they have been presented by way of example only, and not limitation. Thus, the breadth and scope of a preferred embodiment should not be limited by any of the above-described exemplary systems and methods.
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Exemplary systems and methods include a distribution device that maintains a dock rate and distributes a series of tasks to a group of execution devices. Each task has a plurality of samples per frame associated with a time stamp indicating when the task is to be executed. The execution devices execute the series of tasks at the times indicated and adjust the number of samples per frame in relation to the dock rate maintained by the distribution device.
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TECHNICAL FIELD OF THE INVENTION
The present invention generally relates to ink jet printing fluorescent ink compositions, and particularly to ink jet printing fluorescent ink compositions whose marks resist blushing, bleeding, or fading as a result of exposure to water.
BACKGROUND OF THE INVENTION
Ink jet printing is a well-known technique by which printing is accomplished without contact between the printing device and the substrate on which the printed characters are deposited. Briefly described, ink jet printing involves the technique of projecting a stream of ink droplets to a surface and controlling the direction of the stream electronically so that the droplets are caused to form the desired printed image on that surface. This technique of noncontact printing is particularly well suited for application of characters onto irregularly shaped surfaces, including, for example, the bottom of glass, metal, or plastic containers, used for holding cosmetic, pharmaceutical, liquor, and health care products.
Reviews of various aspects of ink jet printing can be found these publications: Kuhn et al., Scientific American, April, 1979, 162-178; and Keeling, Phys. Technol., 12(5), 196-303 (1981). Various ink jet apparatuses are described in the following U.S. Pat. Nos.: 3,060,429, 3,298,030, 3,373,437, 3,416,153, and 3,673,601.
In general, an ink jet ink composition must meet certain rigid requirements to be useful in ink jet printing operations. These relate to viscosity, resistivity, solubility, compatibility of components and wettability of the substrate. Further, the ink must be quick-drying, smear resistant, and be capable of passing through the ink jet nozzle without clogging, and permit rapid cleanup of the machine components with minimum effort.
The marking of articles such as bank checks, envelopes, certificates, and the like, as well as food containers such as metal, plastic or glass containers with identification marks for later identification and/or sorting is well known. Several methods have been proposed for producing such security or identification marks. For example, infrared readable bar codes have been proposed. See, e.g., Japanese Patent Application Kokai No. 58-45999 and U.S. Pat. No. 5,366,252.
The methods based on infrared readable materials have the disadvantage that the infrared absorbing bar codes are to some extent visible to the unaided eye and need to be physically concealed. The concealment of the bar code results in covering up of a portion of the article, thereby adversely affecting the aesthetics of the article.
Fluorescent materials have been considered for marking purposes. It is known that fluorescence is the property of a material to emit radiation as the result of exposure to radiation from some other source. The emitted radiation persists only as long as the exposure is subjected to radiation. The fluorescent radiation generally has a wavelength longer than that of the absorbed radiation.
There has been significant developmental activity in the area of fluorescent jet inks for producing security marks on envelopes and documents. For instance, U.S. Pat. No. 5,093,147 discloses a method for providing intelligible marks that are virtually invisible to the unaided eye on the surface of an article. The method employs a jet ink containing an organic laser dye that is poorly absorptive in the visible range of about 400 to 700 nm, is absorptive of radiation in the near infrared range of at least 750 nm, and fluoresces in response to radiation excitation in the infrared range at a wavelength longer than that of the exciting radiation.
U.S. Pat. No. 4,736,425 discloses a method of marking fiduciary documents requiring authentication by the use of certain fluorescent chelates. The method comprises introducing only a part of the elements forming the chelate onto the document to be marked and subsequently contacting the document for authentication purpose with the missing part of the elements forming the chelate to effect the synthesis of the fluorescent chelate. The chelate thus formed is excited by ultraviolet radiation and the resulting fluorescence radiation is detected.
U.S. Pat. No. 4,540,595 discloses a jet ink that can be used to mark documents such as bank checks for automatic identification. The ink contains certain phenoxazine derivative dyes that are visible to the unaided eye and fluoresce in the near infrared region (650 to 800 nm) upon activation using an activating light having a wavelength in the range of 550 to 700 nm. The ink that is visible to the unaided eye is unfortunately not suitable for many security mark applications.
Commonly owned and copending U.S. patent application Ser. No. 08/661,180, filed Jun. 10, 1996, discloses jet ink compositions suitable for marking on white or light colored substrates such as envelopes. The ink composition comprises a fluorescent colorant and an ink carrier. The colorant comprises a rare earth metal and a chelating agent. The mark produced by the ink composition is completely or substantially invisible to the unaided eye and is visible only when excited by ultraviolet light.
Metal containers such as, for example, empty containers used to can foods or beverages such as coffee, beer, soup, and others are shipped to the fillers with identification marks placed thereon by the container manufacturer. At the fillers' premises, the containers are subjected to various treatments including autoclaving in presence of steam, and immersing the containers in water. The autoclaving is carried out at temperatures as high as 250° F. for times up to 30 minutes. The immersion testing typically is carried out by immersing the containers in selected temperature waters ranging from ice water to boiling water for a period ranging from about 5 minutes to about 30 minutes. It has been a problem with some of the previously known fluorescent jet ink compositions that the marks tend to blush, bleed, or fade as a result of one or more of these treatments. When the mark becomes visible to the unaided eye, it is said to have blushed. When the mark becomes diffuse, it said to have bled. When the mark becomes unreadable or poorly readable due to reduced color intensity, it is said to have faded.
In the area of marking objects such as metals, the following publications are of interest. German Patent DE 3529798 reportedly discloses a jet ink for placing on metals, plastics, paper, or glass identification marks that are invisible to the naked eye consisting of an alcohol solvent, a fluorescent substance that is soluble in a water/ethanol mixture, a water-soluble polyacrylate, and optionally a water-soluble cellulose ester and diethanolamine.
German Patent DE 4013456 reportedly discloses a jet ink containing an organic solvent, a fluorescent dyestuff, a polyamic acid or polyimide binder resin, and conductive salts. The ink is said to adhere well to glass, ceramic, and copper.
Commonly owned and copending U.S. patent application Ser. No. 08/686,191, filed Jul. 26, 1996, discloses a jet ink composition suitable for producing blush resistant marks that are invisible to the unaided eye and are visible only when excited by an exciting radiation comprising a solvent, a fluorescent colorant, a binder resin, and a plasticizer having a vapor pressure of about 15 mm Hg or less at 240° C.
The foregoing indicates that there exists a need for a jet ink composition comprising a fluorescent colorant suitable for printing identification marks on metals, glass, ceramics, and plastics.
Thus, there exists a need for a jet ink composition suitable for printing on substrates, particularly metal containers, marks that resist blushing. There also exists a need for a jet ink composition suitable for printing on substrates, particularly metal containers, marks that resist bleeding. There also exists a need for a jet ink composition suitable for printing on substrates, particularly metal containers, marks that resist fading.
These and other objects of the present invention will be apparent from the detailed description of the preferred embodiments of the invention set forth below.
SUMMARY OF THE INVENTION
The foregoing needs have been fulfilled to a great extent by the present invention which provides a jet ink composition comprising a fluorescent colorant suitable for printing identification marks on metals, glass, plastic, ceramics, or paper.
The jet ink composition of the present invention comprises an ink carrier, a fluorescent colorant, a cellulosic binder resin, and a tetraalkyl ammonium or phosphonium salt.
The marks printed using the inventive jet ink composition have at least one, and preferably more than one, advantage. These advantages are blush resistance, bleed resistance, and fade resistance.
The present invention further provides an improved process of jet printing on metal, glass, plastic, rubber, or paper substrates. The improvement comprises projecting a stream of ink droplets of a jet ink composition to the surface of the substrates and controlling the direction of the stream electronically so that the droplets are caused to form the desired marks on the surface.
While the invention has been described and disclosed below in connection with certain preferred embodiments and procedures, it is not intended to limit the invention to those specific embodiments. Rather it is intended to cover all such alternative embodiments and modifications as fall within the spirit and scope of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention provides jet ink compositions suitable for printing marks that are invisible to the unaided eye and are visible only when excited by an exciting radiation.
The present invention further provides a jet ink composition suitable for producing blush resistant marks that are invisible to the unaided eye and are visible only when excited by an exciting radiation.
The present invention further provides a jet ink composition suitable for producing bleed resistant marks that are invisible to the unaided eye and are visible only when excited by an exciting radiation.
The present invention further provides a jet ink composition suitable for producing fade resistant marks that are invisible to the unaided eye and are visible only when excited by an exciting radiation.
The jet ink composition of the present invention comprises a an ink carrier, a fluorescent colorant, a cellulosic binder resin, and a tetraalkyl ammonium or phosphonium salt.
GENERAL PROPERTIES
In general, the jet ink composition of the present invention exhibit the following characteristics for use in ink jet printing systems: (1) a Brookfield viscosity of from about 1.6 to about 7.0 centipoises (cps) at 25° C.; (2) an electrical resistivity of from about 20 to about 2000 ohm-cm; and (3) a sonic velocity of from about 1100 to about 1700 meters/second.
A detailed discussion of the various components and a method of preparation of the inventive jet ink composition is set forth below.
FLUORESCENT COLORANTS
Any suitable fluorescent colorant that is substantially or completely invisible to the unaided eye can be used in the preparation of the inventive ink composition. The fluorescent colorant absorbs outside the visible range, and fluoresces at a wavelength longer than the absorption wavelength. Preferably, the fluorescent colorant absorbs in the wavelength region of from about 275 nm to about 400 nm and emits in the wavelength region of from about 420 nm to about 520 nm. A fluorescent colorant that emits a blue line is further preferred.
An example of a suitable fluorescent colorant is 2,2'-(2,5-thiophenediyl)-bis(5-tert-butylbenzoxazole), which is available as UVITEX OB from Ciba-Geigy Corp. in Hawthorne, N.Y. UVITEX OB is a yellow crystalline powder having a melting point of 197°-203° C. It has good lightfastness, excellent resistance to heat, and high chemical stability. UVITEX OB can be heated for 8 hours at 300° C. in a nitrogen atmosphere without decomposition. The colorant also can be heated for the same period at 200° C. in air without decomposition. UVITEX OB has an absorption maximum at 375 nm (extinction coefficient 1,200 at 1%, 1 cm) and a fluorescence maximum at 435 nm when measured in ethanol solution. The colorant produces a blue fluorescence. UVITEX OB is known to be useful as an optical brightener in plastics.
Examples of other optical brighteners can be found in Kirk-Othmer Encyclopedia of Chemical Technology, 4, "Fluorescent Brighteners", pp. 213-225 (1978), and include the stilbene derivatives such as 4,4'-bis(triazin-2-ylamino)stilbene-2,2'-disulfonic acid derivatives wherein the triazinyl groups are substituted with suitable substituents, including substituents such as anilino, sulfanilic acid, metanilic acid, methylamino, N-methyl-N-hydroxyethylamino, bis (hydroxyethylamino), morpholino, diethylamino, and the like; mono(azol-2-yl) stilbenes such as 2- (stilben-4-yl) naphthotriazoles and 2-(4-phenylstilben-4-yl)benzoxazoles; bis(azol-2-yl)stilbenes such as 4,4'-bis(triazol-2-yl)stilbene-2,2'-disulfonic acids; styryl derivatives of benzene and biphenyl such as 1,4-bis(styryl)benzenes and 4,4' bis(styryl)biphenyls; pyrazolines such as 1,3-diphenyl-2-pyrazolines; bis(benzazol-2-yl) derivatives having as phenyl ring substituents alkyl, COO-alkyl, and SO 2 -alkyl; bis(benzoxazol-2-yl) derivatives; bis(benzimidazol-2-yl) derivatives such as 2-(benzofuran-2-yl)benzimidazoles; coumarins such as 7-hydroxy and 7-(substituted amino) coumarins, 4-methyl-7-amino-coumarin derivatives, esculetin, β-methylumbelliferone, 3-phenyl-7-(triazin-2-ylamino)coumarins, 3-phenyl-7-aminocoumarin, 3-phenyl-7-(azol-2-yl)coumarins, and 3,7-bis(azolyl)coumarins; carbostyrils, naphthalimides, alkoxynaphthalimides, derivatives of dibenzothiophene-5,5-dioxide, pyrene derivatives, and pyridotriazoles.
Coumarin type fluorescent colorants can be obtained commercially from BASF Corp. in Holland, Mich. Thus, coumarin is sold as CALCOFLUOR WHITE LD or Fluorescent Brightener 130, which has an absorption maximum at 367.8 nm and an emission maximum at 450 nm. Aminocoumarin is sold as CALCOFLUOR WHITE RWP Conc. or RW Solution. The aminocoumarins have an absorption maximum at 374.5 nm and an emission maximum at 450 nm.
Other examples of fluorescent colorants include rare earth metal chelates, and preferably, lanthanide chelates. Examples of lanthanide chelates include those formed by the chelation of organic ligands such as acetylacetone, benzoylacetone, dibenzoylmethane, and salicylic acid with lanthanide ions such as neodymium, europium, samarium, dysprosium, and terbium ions. Examples of such complexes include europium acetylacetonate, samarium acetylacetonate, neodymium benzoylacetonate, terbium salicylate, and dysprosium benzoylacetonate. The aforesaid chelates can be prepared by any suitable method known to those of ordinary skill in the art. For example, a ligand such as acetylacetone can be reacted under suitable conditions with a rare earth metal halide such as europium trichloride to produce the rare earth metal chelate. For additional details, see U.S. Pat. No. 4,736,425. The above chelates absorb ultraviolet radiation and fluoresce in the visible range. The acetylacetonate of europium fluoresces with an emission line in the red region and this is particularly suitable for printing on white or light colored substrates.
Examples of commercially available rare earth chelate fluorescent colorants suitable for use in the ink composition of the present invention include, but are not limited to, the rare earth metal chelates sold as LUMILUX C™ pigments by Hoechst-Celanese Corp. in Reidel-de Haen, Germany.
The LUMILUX C rare earth metal organic chelates have a melting point of from about 130° C. to about 160° C. and a bulk density of from about 500 kg/m 3 to about 1100 kg/m 3 . Examples of organic LUMILUX C pigments include Red CD 316, Red CD 331, Red CD 332, Red CD 335, and Red CD 339, which are yellowish when unexcited and fluoresce in the orange-red region when excited by ultraviolet radiation. These pigments are soluble in organic solvents. Red CD 331, a preferred pigment and a derivative of europium-acetonate, is a yellowish powder having an emission peak at 612 nm, a melting point in the range of 153°-155° C., and a density of 600 kg/m 3 . Red CD 331 is soluble in acetone, ethylacetate, ethanol, xylene, dichloromethane, dimethylformamide, n-hexane, and dibutylphthalate. Red 316 is a rare earth acetylacetonate. Red CD 332, a rare earth biketonate, has a melting of 135°-138° C. and a density of 500 kg/m 3 . Red CD 335, an europium chelate, has a melting point of 133° C. and a density of 1030 kg/m 3 .
Additional examples of suitable LUMILUX pigments include Red CD 105, Red CD 106, Red CD 120, and Red CD 131. These are inorganic pigments. Red CD 105 is white when unexcited, fluoresces in the orange-red region when excited by ultraviolet radiation, and has a median particle size of 7 microns. Red CD 106 is white when unexcited, fluoresces in the orange-red region when excited by ultraviolet radiation, and has a median particle size of 6 microns. Red CD 120 is white when unexcited, fluoresces in the red region when excited by ultraviolet radiation, and has a median particle size of 2.7 microns. Red CD 131 is white when unexcited, fluoresces in the red region when excited by ultraviolet radiation, and has a median particle size of 6.5 microns. It is preferred that the particle size of the aforesaid pigments is further reduced by suitable means including grinding and crushing for use in the preparation of the jet ink composition.
Examples of other fluorescent colorants include the porphyrin type dyes described in U.S. Pat. No. 5,256,193. These include, e.g., the tetra- chloride, bromide, tosylate, triflate, perchlorate, acetate, and fluoroborate salts of 5,10,15,20-tetrakis-(1-methyl-4-pyridyl)-21H,23H-porphine, 5,10,15,20-tetrakis-(l-hydroxymethyl-4-pyridyl)-21H,23H-porphine, 5,10,15,20-tetrakis- 1-(2-hydroxyethyl)-4-pyridyl!-21H,23H-porphine, 5,10,15,20-tetrakis- 1-(3-hydroxypropyl)-4-pyridyl!-21H,23H-porphine, 5,10,15,20-tetrakis- 1-(2-hydroxyethoxyethyl)-4-pyridyl!-21H,23H-porphine, and 5,10,15,20-tetrakis- 4-(trimethylammonio)phenyl!-21H,23H-porphine. These colorants are excitable in the 380-500 nm range, and fluoresce in the 600-800 nm range.
Any suitable amount of the colorant can be used to prepare the jet ink composition of the present invention. If the ultraviolet absorptivity or the fluorescent emission intensity is high, then a small amount of the colorant is sufficient. If the ultraviolet absorptivity or the fluorescent emission intensity is low, then the amount of the colorant used should be increased. The colorant is used preferably in an amount of from about 0.01% by weight to about 1% by weight of the jet ink composition, and more preferably in an amount of from about 0.1% by weight to about 0.5% by weight of the jet ink composition.
INK CARRIER
The jet ink composition of the present invention comprises one or more solvents as the ink carrier. Any suitable solvent can be used in the preparation of the inventive jet ink composition, and preferably one or more organic solvents are employed. It is further preferred that the solvent evaporates rapidly under the printing conditions and without leaving behind a solvent residue. Organic solvents suitable for the preparation of the jet ink composition of the instant invention include ketones such as acetone, methyl ethyl ketone, diethyl ketone, cyclohexanone, and the like, esters such ethyl acetate, propyl acetate, butyl acetate, amylacetate, and the like, alcohols such methanol, ethanol, n-propanol, isopropanol, n-butanol, i-butanol, t-butanol, n-pentanol, n-hexanol, and the like. If desired, a mixture of solvents may be used.
Any suitable amount of the ink carrier can be used in the preparation of the jet ink composition of the present invention. The ink carrier is typically present in an amount of from about 30% to about 80% by weight, and preferably in an amount of from about 60% to about 75% by weight of the jet ink composition.
BINDER RESINS
The jet ink composition of the present invention comprises at least one binder resin which forms a film on the colorant. The binder resin also serves to improve the adhesion of the colorant and other ingredients to the printed surface. The binder resin is preferably colorless and thus does not impart visibility to the marks. Any suitable binder resin can be employed, and preferably a good film former is employed. A good film former rapidly forms a tough durable film as the result of the evaporation of the solvent.
It is preferred that the binder resin, or the main binder resin when a mixture of binder resins is employed, has a melting point or softening point above about 100° C. It is further preferred that the melting or softening point is about 120° C. or higher, and it is even further preferred that the melting or softening point is in the range of from about 120° C. to about 200° C. In certain embodiments of the present invention, the melting point or softening point of the binder resin can be about 150° C. or higher, especially for producing a mark that can survive the autoclaving treatment.
It is further preferred that the binder resin has low water absorption, preferably below about 3% by weight of the binder resin, and more preferably below about 1% by weight of the binder resin. It is also preferred that the binder resin has a low acid number, preferably below about 50, and more preferably below about 10. It is further preferred that the binder resin is soluble in common organic solvents such as ketones, alcohols, or esters.
Examples of suitable binder resins include cellulosic resins such as nitrocellulose, cellulose acetate, cellulose acetate butyrate, and cellulose acetate propionate. Several grades of nitrocellulose, a preferred binder resin, are available commercially, e.g., from Hercules, Inc. in Wilmington, Del. These grades vary in nitrogen content and viscosity. The nitrogen content of the nitrocellulose resin is preferably in an amount of from about 11% by weight to about 13% by weight, and more preferably in an amount of from about 11.8% by weight to about 12.2% by weight of the resin. Hercules' RST™ type nitrocellulose has an average nitrogen content of 12% by weight and is available in a large number of viscosity grades, from 10 centipoises to about 2,000 seconds, measured on a 12.2% by weight solution in toluene. The nitrocellulose resin having low viscosities, e.g., a viscosity of about 10-15 cps, is particularly preferred.
The RS type nitrocellulose resins have a softening point range of 155°-220° C., and the moisture absorption of unplasticized clear film at 21° C. in 24 hours in 80% relative humidity is 1% by weight.
Cellulose acetate propionate (CAP) and cellulose acetate butyrate (CAB) can be obtained from Eastman Chemical, Kingsport, Tenn. CAB-553-0.4 has a glass transition temperature of 136° C. and a melting point of 150° C., and CAP-504-0.2 has a glass transition temperature of 159° C. and a melting point of 190° C.
The binder resin can be present in the jet ink composition in any suitable amount. It is preferably present in an amount of from about 5% by weight to about 15% by weight of the jet ink composition, and more preferably in an amount of from about 10% by weight of the jet ink composition.
Certain embodiments of the jet ink composition include, in addition to the cellulosic resin, a silicone resin. For example, it has been found that uncoated aluminum substrates can be printed advantageously using jet ink compositions containing nitrocellulose and silicone resins.
Any suitable silicone resin can be used, linear, branched or crosslinked, preferably those having a weight average molecular weight of from about 1000 to about 10,000, more preferably those having a weight average molecular weight of from about 2000 to about 8000, and even more preferably those having a weight average molecular weight of from about 2000 to about 4000. A particularly preferred silicone resin is the DOW CORNING™ 6-2230 resin. The DC-6-2330 resin has a silanol content of 5% by weight of the resin, a weight average molecular weight of 2000-4000, and a degree of crosslinking of 1.2 on a scale where 1.0 is completely crosslinked and 2.0 is fully linear.
The silicone resin can be present in the jet ink composition in any suitable amount. It is typically present in an amount of up to about 5% by weight of the jet ink composition, preferably in an amount of from about 1% by weight to about 3% by weight of the jet ink composition.
SURFACTANT
The jet ink composition may further contain a surfactant, which may be anionic, cationic, nonionic, or amphoteric. Examples of anionic surfactants include alkylbenzene sulfonates such as dodecylbenzene sulfonate, alkylnaphthyl sulfonates such as butyl or nonyl naphthyl sulfonate, dialkyl sulfosuccinates such as diamyl sulfosuccinate, alcohol sulfates such as sodium lauryl sulfate, and perfluorinated carboxylic acids such as perfluorodecanoic acid and perfluorododecanoic acid. Nonionic surfactants include the alkylesters of polyethylene glycol, fatty acid esters of glycerol, fatty acid esters of glycol, and the like, and fluorochemical surfactants such as FC 170C, FC 430, FC 431, FC 740, FC 120, FC 248, FC 352, FC 396, FC 807, and FC 824, which are available from 3M Co. FC 430 and FC 431 are fluoroaliphatic polymeric esters. Cationic surfactants include alkylamines, amine oxides, amine ethoxylates, alkyl hydroxyalkyl imidazolines, quaternary ammonium salts, and amphoteric surfactants include the alkylbetaines, the amidopropylbetaines, and the like.
The surfactant may be present in the jet ink composition in any suitable amount. When a surfactant is used, it is typically used in an amount of from about 0.01% to about 1% by weight of the jet ink composition, and preferably in an amount of about 0.1% by weight of the jet ink composition.
PLASTICIZER
The jet ink composition of the present invention includes one or more plasticizers. It is believed that the plasticizer may also contribute to the improved properties of the marks, particularly the blush resistance. It is also believed that the hydrophobic plasticizer prevents or retards the diffusion of water, especially hot water, into the film formed by the binder resin.
Any suitable hydrophobic plasticizer can be used. Examples of suitable plasticizers include trialkyl phosphates, wherein the alkyl group can be branched or linear and have about 1 to about 10 carbon atoms, preferably about 3 to about 5 carbon atoms. A particular example of a suitable plasticizer is tributyl phosphate, which also acts as a flame retardant.
The plasticizer can be present in the jet ink composition in any suitable amount. It is typically present in an amount of up to about 5% by weight, and preferably in an amount of from about 1% to about 3% by weight of the jet ink composition.
HIGH BOILING SOLVENT
The jet ink composition of the present invention may further contain a high boiling solvent, preferably a hydrophilic high boiling solvent. When the jet printed ink dries on the substrate, due to the evaporation of the volatile solvents, the mark can cool rapidly and absorb moisture from the surrounding. The absorbed moisture can impart a cloudly appearance to the film formed on the colorant. It has been observed that by including a high boiling hydrophilic solvent in the ink composition, it is possible to reduce or eliminate the development of cloudiness. The hydrophilic solvents have boiling points preferably above 100° C., and more preferably in the range of from about 150° C. to about 250° C.
Any suitable hydrophilic high boiling solvent known to those of ordinary skill in the art can be used. Examples of suitable high boiling solvents include glycols such as ethylene glycol, propylene glycol, glycerin, diglycerin, diethylene glycol, and the like, glycol ethers such as ethylene glycol dimethyl ether, ethylene glycol diethylether, cellosolve, diethylene glycol monoethylether (Carbitol), diethylene glycol dimethylether, and diethylene glycol diethylether dialkyl sulfoxides such as dimethyl sulfoxide, and other solvents such as sulfolane, N-methyl pyrrolidinone (NMP), and the like. NMP is a preferred high boiling solvent.
Any suitable amount of the high boiling solvent can be used, preferably in an amount of up to about 5% by weight of the jet ink composition, and more preferably in an amount of from about 2% by weight to about 4% by weight of the jet ink composition.
CONDUCTIVITY AGENT
The jet ink composition of the present invention further contains a conductivity agent which offers the desired electrical conductivity to the jet ink composition. It has been found that hygroscopic electrolytes tend to absorb water into the mark when exposed to high humidity or water. It is believed that the absorbed water forms micro-droplets in the film on the substrate. When water is later evaporated during drying of the marks, micro-voids are formed in the film, and the micro-voids scatter light. The difference between the refractive indices of the resin(s), which are generally greater than 1, and of air, which is 1, is responsible for the scattering effect. The scattering of light contributes to blushing.
It has been discovered that non-hygroscopic conductivity agents are effective in reducing or eliminating blushing. Any suitable non-hygroscopic conductivity agent can be used, preferably an organic salt is used. Examples of suitable organic salts include tetraalkyl ammonium salts and tetraalkyl phosphonium salts. The alkyl groups can be of any suitable number of carbon atoms, preferably about 1-10 carbon atoms, and more preferably about 2 to about 5 carbon atoms. Particular examples of preferred conductivity agents include tetraethyl or tetrabutyl ammonium or phosphonium salts. The salts can contain any suitable anion. Examples of suitable anions include chloride, bromide, and p-toluenesulfonate. Thus, particular examples of non-hygroscopic conductivity agents include tetraethyl ammonium chloride, tetraethyl ammonium bromide, tetrabutyl ammonium chloride, tetrabutyl ammonium bromide, tetrabutyl phosphonium chloride, tetrabutyl phosphonium bromide, and tetraethyl ammonium p-toluenesulfonate, which can be obtained from Aldrich Chemical Co. in Milwaukee, Wis.
Any suitable amount of the conductivity agent can be used to achieve the desired electrical conductivity. The agent is preferably present in the jet ink composition in an amount of from about 0.1% to about 2% by weight of the jet ink composition, and more preferably in an amount of from about 0.4% by weight to about 1.2% by weight of the jet ink composition.
The jet ink composition of the present invention can be prepared by any suitable method known to those of ordinary skill in the art. For example, the components can be sequentially added to a mixer and blended until a smooth ink composition is obtained. The ink composition can be filtered, e.g., using a 5-micron sock filter, to remove any impurities.
The following examples further illustrate the present invention but, of course, should not be construed as in any way limiting its scope.
EXAMPLE 1
This Example illustrates a preferred combination of the various ingredients of the jet ink composition of the present invention. IPA below stands for isopropanol.
______________________________________Materials Preferred Range, Wt. %______________________________________Acetone (Solvent) about 50.0-about 95.0Methanol (Solvent) up to about 30.01-Methyl 2-Pyrrolidone (Solvent) up to about 5.0Nitrocellulose RS (10-15 cps, about 5.0-to about 15.0wetted with 30% IPA) (Binder)Silicon DC6-2230 (Binder) up to about 5.0Tetrabutylphosphonium Bromide about 0.4-to about 1.2(Conductive salt)Tributyl phosphate (Plasticizer) about 1.0-to about 5.0FC-430 (10% in acetone) up to about 1.0(Surfactant)UVITEX OB (Brightener) about 0.1-to about 0.5______________________________________
EXAMPLE 2
This Example illustrates an optimal combination of ingredients of the jet ink composition of the present invention illustrated in Example 1.
______________________________________Materials Wt. %______________________________________Acetone 62.5Methanol 19.51-methyl-a-pyrrolidome 3.0Nitrocellulose 10.0Silicone DC6-2230 2.0Tetrabutylphosphonium bromide 0.6Tributylphosphate 2.0FC-430 0.1UVITEX OB 0.3 100.0______________________________________
A jet ink composition was prepared using the ingredients listed above by combining and mixing them until a smooth ink composition was obtained.
EXAMPLE 3
This Example illustrates another preferred combination of the various ingredients that can be used to prepare a jet ink composition of the present invention.
______________________________________Materials Preferred Range, Wt %______________________________________Methyl ethyl ketone about 30.0-to about 80.0(Solvent)Methanol (Solvent) about 10.0-to about 50.01-Methyl 2-Pyrrolidone up to about 5.0(Solvent)Nitrocellulose RS (10-15 cps, about 5.0-to about15.0wetted with 30% IPA)(Binder)Silicon DC6-2230 (Binder) up to about 5.0Tetrabutylphosphonium Bromide about 0.5-to about 1.5(Conductive salt)Tributyl phosphate about 1.0-to about 5.0(Plasticizer)FC-430 (10% in acetone) up to about 1.0(Surfactant)UVITEX OB (Brightener) about 0.1-to about 1.0______________________________________
EXAMPLE 4
This Example illustrates an optimal combination of ingredients of the jet ink composition of the present invention illustrated in Example 3.
______________________________________Materials Wt. %______________________________________Methyl ethyl ketone 61.65Methanol 20.01-Methyl-2-pyrrolidone 3.0Nitrocellulose 10.0Silicone DC6-2230 2.0Tetrabutylphosphonium bromide 1.0Tributylphosphate 2.0FC-430 0.1UVITEX OB 0.25 100.00______________________________________
A jet ink composition was prepared using the ingredients listed above by combining and mixing them until a smooth ink composition was obtained.
EXAMPLE 5
This Example illustrates another preferred combination of the various ingredients of the jet ink composition of the present invention.
______________________________________Materials Preferred Range, Wt. %______________________________________Acetone (Solvent) about 50.0-to about 95.0Duplicating fluid #5, up to about 30.0anhydrous (Solvent)1-Methyl 2-Pyrrolidone up to about 5.0(Solvent)Nitrocellulose RS (10-15 cps, about 5.0-to about 15.0wetted with 30% IPA)(Binder)Silicon DC6-2230 (Binder) up to about 5.0Tetrabutylphosphonium Bromide about 0.4-to about 1.2(Conductive salt)Tributyl phosphate about 1.0-to about 5.0(Plasticizer)FC-430 (10% in acetone) up to about 1.0(Surfactant)UVITEX OB (Brightener) about 0.1-to about 0.5______________________________________
EXAMPLE 6
This Example illustrates an optimal combination of the ingredients of the jet ink composition of the present invention illustrated in Example 5.
______________________________________Materials Wt. %______________________________________Acetone 71.65Duplicating fluid #5, 10.0anhydrous (Solvent)1-Methyl 2-Pyrrolidone 3.0(Solvent)Nitrocellulose RS (10-15 cps, 10.0wetted with 30% IPA) (Binder)Silicone DC6-2230 2.0Tetrabutylphosphonium Bromide 1.0(Conductive salt)Tributyl phosphate (Plasticizer) 2.0FC-430 (10% in acetone) 0.1UVITEX OB 0.25 100.00______________________________________
A jet ink composition was prepared using the ingredients listed above by combining and mixing them until a smooth ink composition was obtained. Duplicating fluid #5 is ethanol denatured with isopropanol and n-propyl acetate.
EXAMPLE 7
This Example illustrates the properties of the marks produced from the inventive ink compositions set forth in Examples 2, 4, and 6. Metal cans from three different suppliers were employed in this study. The cans from supplier 1 were made of aluminum, steel, and tin. The cans from supplier 2 were made of aluminum, and the cans from supplier 3 were made of steel and tin. The cans were subjected to testing under a variety of conditions. The results obtained are set forth below and confirm that the marks have excellent fading, bleeding and blushing resistance.
______________________________________ Fading/Bleeding/Blushing* Example 2 Example 4 Example 6______________________________________Cans From Supplier 1Retort 250° F./30 min (Cans No/No/0 No/No/0 No/No/0filled w/98° C. water)50° C./5 min (Cans filled No/No/0 No/No/0 No/No/0w/98° C. water)40° C./5 min (cans filled No/No/0 No/No/0 No/No/0w/98° C. water)35° C./5 min (cans filled No/No/0 No/No/0 No/No/0w/98° C. water)Coated Cans From Supplier 2Retort (125° C./30 mins) No/No/0 No/No/0 No/No/0Dipped in 100° C. water/30 min No/No/0 No/No/0 No/No/0Dipped in 80° C. water/30 min No/No/0 No/No/0 No/No/0Dipped in 60° C. water/30 min No/No/0 No/No/0 No/No/0Dipped in 40° C. water/30 min No/No/0 No/No/0 No/No/0Uncoated Cans From Supplier 2Retort (125° C./30 mins) No/No/1 No/No/1 No/No/1Dipped in 100° C. water/30 min No/No/0 No/No/0 No/No/0Dipped in 80° C. water/30 min No/No/0 No/No/0 No/No/0Dipped in 60° C. water/30 min No/No/0 No/No/0 No/No/0Dipped in 40° C. water/30 min No/No/0 No/No/0 No/No/0Cans from Supplier 3with red coating No/No/0 No/No/0 No/No/0(150° F./5 min)with black coating No/No/0 No/No/0 No/No/0(150° F./5 min)______________________________________ *Blushing is reported on a scale of 0-4. A blushing value of 0 indicates absence of blushing, and a value of 1 indicates very slight blushing. A mark that exhibits extreme blushing will be rated 4.
All of the references, including patents and publications, cited herein are hereby incorporated in their entireties by reference.
While this invention has been described with an emphasis upon the preferred embodiment, it will be obvious to those of ordinary skill in the art that variations of the preferred embodiment may be used and that it is intended that the invention may be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications encompassed within the spirit and scope of the invention as defined by the following claims.
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Disclosed is a jet ink composition suitable for printing marks on metal, glass, plastics, rubber, or paper comprising an ink carrier, a fluorescent colorant, a cellulosic binder resin, and a tetraalkyl ammonium or phosphonium salt. The jet printed marks do not blush, bleed, or fade, as a result of exposure to steam, or hot and cold water. Also disclosed is an improved process of jet printing on substrates comprising printing with the disclosed jet ink composition.
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FIELD OF THE INVENTION
[0001] This invention relates to a training device for rehabilitation of individuals suffering from neurological injuries. More particularly, the present invention relates to a device that utilizes both mechanical and electrical stimulation of individual's muscles.
DESCRIPTION OF THE BACKGROUND
[0002] The recovery of walking is one of the main goals of patients after a neurological impairment (including stroke, multiple sclerosis, cerebral palsy and spinal cord injury (SCI)) as limitations in mobility can adversely affect most activities of daily living. Following a neurological injury, there is often impaired control of balance, paralysis, or weakness of lower extremity muscles including commonly those that activate the ankle. This often has a substantial adverse impact on walking. Specifically, individuals may suffer difficulties supporting their body weight during the stance phase, or shifting weight during the transition to swing, or lifting their foot for toe clearance during the swing phase due to the weakness associated with the injury. Gait training can be done
i. with therapist-assisted over ground ambulation (with or without assistive device) ii. in a Body Weight Supported Treadmill Training (BWSTT) environment, where assistance for the movement of legs and the pelvis is provided manually by a therapist or iii. by a robotic device (Lokomat, Auto-Ambulator or Gait Trainer), or in water (weight supported environment, with or without a treadmill).
Over ground gait training (with or without a Functional Electrical Stimulation (FES) orthosis) can only be used for individuals with already able to support body weight in an upright position.
[0006] BWSTT, robotic device gait training and aquatherapy gait training (training in water) can potentially be used to enhance loco-motor abilities in neurologically impaired individuals, as lack of trunk balance and ability to bear weight in an upright position are replaced by the supporting abilities of the device or environment used (harness, exoskeleton or water). But they are not typically used in clinical practice to aid in locomotor training in individuals with motor complete impairments as this training would need specialized, center based, expensive environment (i.e. therapeutic pool, robotic exoskeleton) or is very labor intensive (sometimes requiring 2-3 therapists' sustained effort over long periods of time).
[0007] BWSTT with manual or robotic assistance of the legs and the pelvis has been used as a promising rehabilitation method designed to improve motor function and ambulation in people with SCI (Behrman and Harkema 2000; Dietz et al. 1995; Wernig and Muller 1992; Wirz et al. 2005; Dobkin et al. 2006; Field-Fote et al. 2005). However, while BWSTT has been shown to provide improvements in locomotor ability, motor function, and balance for some patients, the current technology used to assist with the training is typically very expensive, requires trained therapists for utilization and can only be used in a rehabilitation center. Several robotic BWSTT systems have been developed for automating locomotor training, including the Lokomat (Colomboet al. 2000) and Gait Trainer (GT) (Hesse and Uhlenbrock 2000).
[0008] The Lokomat is a motorized exoskeleton that drives hip and knee motion with fixed trajectory using four DC motors (Colombo et al. 2000). One limitation is that it is difficult to back drive the Lokomat because it uses high advantage, ball screw actuator. The GT rigidly drives the patient's feet through a stepping motion using a crank-and-rocker mechanism attached to foot platforms (Hesse and Uhlenbrock 2000). These robotic systems have their basic design goal to assist patients in producing correctly shaped and timed locomotor movements. This approach is effective in reducing therapist labor in locomotor training and increasing the total duration of training, but shows relatively limited functional gains for some patients (Wirz et al. 2005; Field-Fote et al. 2005). For instance, only 0.11 m/s gait speed improvement is obtained following prolonged training using the Lokomat (Wirz et al. 2005).
[0009] FES has been previously used to enhance the quality of gait training whether as an assistive device (FES orthosis for foot drop) or to enhance muscle strength and improve cardiovascular resistance (FES ergometer), thus decreasing gait induced fatigue. FES has also been used extensively in the rehabilitation of individuals with SCI to:
i. improve muscle mass and strength (Frotzler A, Coupaud S, Perret C, Kakebeeke T H, Hunt K J, Eser P. Effect of detraining on bone and muscle tissue in subjects with chronic spinal cord injury after a period of electrically-stimulated cycling: a small cohort study. Swiss Paraplegic Research, Nottwil, Switzerland; Thomas Mohr, Jesper L Andersen, Fin Biering-Sùrensen, Henrik Galbo, Jens Bangsbo, Aase Wagner and Michael Kjaer. Long term adaptation to electrically induced cycle training in severe spinal cord injured individuals. Spinal Cord (1997) 35, 1±16) ii. control spasticity (Maria Knikou, PhD, and Bernard A. Conway, PhD. Reflex Effects Of Induced Muscle Contraction In Normal And Spinal Cord Injured Subjects. Muscle Nerve 26: 374-382, 2002; Daly J., et al. Therapeutic neural effects of electrical stimulation. IEEE Trans Rehabil Eng 4:218-230, 1996; Robinson C. J., et al. Spasticity in Spinal-Cord Injured Patients 0.1. Short-Term Effects of Surface Electrical-Stimulation. Arch Phys Med Rehab 69:598-604, 1988) iii. improve cardiovascular endurance and respiratory function (Puran D Faghri, Roger M Glaser, Stephen F Figoni. Functional Electrical Stimulation Leg Cycle Ergometer Exercise: Training Effects on Carriorespiratory Responses of Spinal Cord Injured Subjects at Rest and During Submaximal Exercise. Arch Phys Med Rehabil 73:1085-1093) iv. improve bone mass (Belanger M, Stein R B, Wheeler G D, Gordon T, Leduc B. Electrical stimulation: can it increase muscle strength and reverse osteopenia in spinal cord injured individuals? Arch Phys Med Rehabil 2000; 81(8):1090-1098; McDonald J W, Becker D, Sadowsky C L, Jane J A, Sr., Conturo T E, Schultz L M. Late recovery following spinal cord injury. Case report and review of the literature. J Neurosurg 2002; 97(2 Suppl):252-265) and v. improve body composition (L. Griffin, M. J. Decker, J. Y. Hwang, B. Wang, K. Kitchen, Z. Ding, J. L. Ivy. Functional electrical stimulation cycling improves body composition, metabolic and neural factors in persons with spinal cord injury. J Electromyography and Kinesiol 2008: 1-8).
[0015] FES has been postulated to even alter neuronal control, altering central nervous system plasticity and improving functional tasks performance (Richard K. Shields and Shauna Dudley-Javoroski. Musculoskeletal Plasticity After Acute Spinal Cord Injury: Effects of Long-Term Neuromuscular Electrical Stimulation Training. J Neurophysiol 95: 2380-2390, 2006).
[0016] Combining gait training with FES activation of selected muscles involved in stepping has been already achieved and there are several commercially available FES driven orthosis for utilization in individuals with SCI, mainly to correct foot drop (Bioness L300, Walk Aid). In addition, in clinical practice, therapists are frequently utilizing hand held triggered neuromuscular electrically stimulated (NMES) devices to aid in foot/toe clearing during the swing phase of the gait when working with individuals with neurologic lower limb weakness.
SUMMARY OF THE INVENTION
[0017] One object of the present invention is to provide a functional electrical stimulation step and stand system comprising two footplates (left and right) connected to a primary drive motor that cause the footplates to move in a reciprocal motion. The footplates are further connected to corresponding servos, which allow for control of the movement of the footplate with respect to an axis. The ability to control the movement of the footplate is defined as the firmness of the footplate.
[0018] In a further object of the present invention, the system comprises an electrical stimulation control unit. The control unit has electrical stimulation leads that connect to electrodes that deliver an electrical impulse to a patient's muscles. In a further embodiment, the control unit has one or more wireless stimulators.
[0019] In yet an additional object of the present invention, the system has a hoist and harness that helps a patient stand upright on the footplates. In one preferred embodiment, the hoist and harness provide weight control measurements to the control unit. The control unit, in turn, utilizes that information to controls the electrical stimulation delivered to the patient's muscles.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The above and other features, aspects, and advantages of the present invention are considered in more detail, in relation to the following description of embodiments thereof shown in the accompanying drawings, in which:
[0021] FIG. 1 is a picture of a device in accordance with one embodiment of the invention.
[0022] FIG. 2 is a graphical representation of a stepper assembly in accordance with one embodiment of the present invention.
[0023] FIG. 3 is a graphical representation of the stepper assembly in the standing position.
[0024] FIG. 4 is a perspective view of the stepper assembly.
[0025] FIG. 5 is a detailed view of the foot plate.
[0026] FIG. 6 is a detailed view of the foot plate with the servo plate removed.
[0027] FIG. 7 is a detailed view of the foot plate showing the servo drive belt.
[0028] FIG. 8 is a graphical representation of the control unit.
[0029] FIG. 9 is a front view of the patient hoist.
[0030] FIG. 10 is a front view of the harness.
[0031] FIG. 11 is a graph showing the displacement of the pedals with and without servo input.
[0032] FIG. 12 is a graph that shows the various positions of the servo can be commanded.
[0033] FIG. 13 is a graph that shows the result of commanding the servo to move the foot plate for a normal gait.
DETAILED DESCRIPTION
[0034] The invention summarized above may be better understood by referring to the following description, the accompanying drawings, and the claims listed below. This description of an embodiment, set out below to enable one to practice an implementation of the invention, is not intended to limit the preferred embodiment, but to serve as a particular example thereof. Those skilled in the art should appreciate that they may readily use the conception and specific embodiments disclosed as a basis for modifying or designing other methods and systems for carrying out the same purposes of the present invention. Those skilled in the art should also realize that such equivalent assemblies do not depart from the spirit and scope of the invention in its broadest form.
[0035] As shown in FIG. 1 , one embodiment of the invention is a trainer 100 that combines a robotic device that simulates stepping and standing with FES while the individual 110 is safely supported in a harness 120 . This design has the potential to tap into neuro-plasticity driven loco-motor patterning while increasing muscle strength and cardiovascular endurance and be safely applied in a center or home-based environment.
[0036] The motion of the individual's feet is controlled by a foot assembly 200 as shown in FIG. 2 . The foot assembly 200 (also referred to as the stepper assembly) incorporates three motors. The primary drive motor 210 provides for transverse motion of foot plates 220 while a servo 230 built into both the left and right footplate 220 allow the software to independently control the motion of the foot about the ankle in the sagittal plane. This control can either assist the foot movement being evoked volitionally or electrically or it can resist such movement.
[0037] In one further embodiment of the present invention, a stand training mode allows the foot plates to be brought together helping the individual patient to develop standing skills utilizing a combination of electrically evoked peripheral muscle contractions or volitional and or electrically evoked centrally driven muscle contractions. In this mode the footplate servos 230 can be used to induce perturbations, which the individual can train to counteract.
[0038] The motors controlling each footplate 220 can also be commanded to produce a vibration motion of the footplates in the sagittal plane either during standing or stepping motions. This vibration can be used to deliver therapeutic benefits including the reduction of spasticity. FES driven gait training utilizing the training device 100 will be safe for both motor complete and incomplete neurologically impaired individuals. In addition, the training device 100 can increase the walking abilities of individuals with many types of neurological impairments. Given this the training device 100 can be safely used in a home based environment to perform long term gait training in individuals with varying degrees of neurological related paralysis.
[0039] As shown in FIG. 1 , training device 100 is composed of a stepper assembly 200 , a control unit 130 , and a patient hoist 150 and harness 120 . The stepper assembly 200 , as shown in FIG. 2 , has a drive motor 210 connected to the drive assembly 250 . The drive assembly 250 is connected to the foot plates 220 by cranks 260 (left and right respectively) through a drive arm 280 . The cranks 220 are connected to the drive arm 280 at different positions 270 and held in place by a magnet. The positions 270 determine the step lengths for the foot plates 220 . In one particular embodiment, the drive arm 280 has three positions 270 resulting in 18″, 15″, and 12″ steps. An additional position 290 brings the footplates 220 together proving a standing position to the individual, as shown in FIG. 3 .
[0040] As shown in FIG. 4 , the stepper assembly 200 further comprises an emergency stop 277 that allows a technician to stop the drive assembly 250 from moving the foot plates 220 . FIG. 5 shows a close up view of the right side foot plate 220 and servo 230 . In FIG. 6 , the servo cover 600 has been removed and the servo 230 is shown. The servo 230 motor connects to a drive belt 700 that controls the foot plate 220 as shown in FIG. 7 . Left unpowered, each footplate moves through a range of plantar and dorsi flexion movement that is a natural product of the transverse motion.
[0041] The hoist 150 and harness 120 as shown in FIGS. 9 and 10 are used to position the patient over the stepper assembly 200 in partial body weight. The hoist 150 and harness 120 are connected to load cells that provide weight measurements to the control unit 130 . The control unit 130 utilizes the weight measurements in an electrical stimulation control algorithm that controls the electrical stimulation sent to the leads and stimulators.
[0042] In one particular embodiment, the trainer 100 has a control unit 130 , as shown in FIG. 8 , which includes a computer and a 6 channel stimulator. The stimulator produces the functional electrical stimulation to evoke muscle contractions. The computer controls the operation of the stimulator, the drive motor 210 and the two footplate servos 230 . Software controlling the servo motors which power the left and right footplates can be used to guide a patient's foot through a normal range of motion in the sagittal plane during stepping training.
[0043] When in use, the trainer 100 can be utilized to track the appropriate travel of the individual's feet. FIG. 11 is a graph that shows how the footplate pedal moves with respect to gravity when unpowered (pedal trace) compared with how the ankle of an able bodied individual moves when stepping (target pedal trace) vs. percentage of phase of the gait cycle. Furthermore, in FIG. 12 shows one way in which a footplate servo motor may be commanded to make the footplate's position coincident with normal gait. For example, commanding the motor to move 2452 positions results in a 1 degree movement of the footplate. Superimposing this motor driven footplate movement with the unpowered footplate movement that arises from the transverse motion brings the footplate motion (corrected pedal trace) coincident with the ankle movement of normal gait (target pedal trace) vs. percent of the gait cycle as shown in FIG. 13 .
[0044] Producing this normal ankle movement on this trainer 100 is one of the possible uses of the footplate servo motors. In one exemplary embodiment, the motors are also used to produce vibration while standing or an exaggerated ankle motion for motor skill relearning purposes or a reduced ankle motion to accommodate patients with reduced range of motion in one or both ankle joints. In one exemplary embodiment, software varies the current supplied to each footplate servo which has the effect of varying the firmness of the footplate. Footplate firmness can be varied during a therapy session for example to gradually overcome plantar flexion muscle tone.
[0045] In one embodiment of the present invention, the control unit 130 provides up to 10 channels of electrical stimulation. It is contemplated that any number of channels may be utilized to provide electrical stimulation. In one alternative embodiment, the control unit 130 further includes a 6 channel electrical stimulator and a BlueTooth communications link that allows it to control up to four additional single channel stimulators.
[0046] The muscle groups to be stimulated are selected based upon how the patient presents. For example a hemiparetic patient may only require muscles on one side to be electrically stimulated.
[0047] Our invention allows the following muscle groups to be selected for electrical stimulation each either bilaterally or unilaterally:
Gluteals Quadriceps Hamstrings Gastrocnemius Anterior tibialis Erector spinae Abdominals
The electrical stimulation is delivered to each muscle group via adhesive skin surface electrodes at the appropriate time in the gait cycle as determined by the position of drive arms in their circular path.
[0055] A further embodiment of the invention allows the electrical stimulation angles to be adjusted. The following is a table of default angles that can be provided in one particular embodiment of the present invention. The 0 degree position is the left drive arm at top dead center.
[0000]
Stimulation
Stimulation
Muscle group
on angle
off angle
Left quadriceps
50
285
Right quadriceps
230
105
Left hamstring
235
70
Right hamstring
55
250
Left gluteal
90
245
Right gluteal
270
65
Left gastroc
235
70
Right gastroc
55
250
Left anterior tibialis
50
285
Right tibialis
230
105
Left abdominal
340
180
Right abdominal
160
359
Left erector spinae
190
290
Right erector spinae
10
110
[0056] The invention has been described with references to a preferred embodiment. While specific values, relationships, materials and steps have been set forth for purposes of describing concepts of the invention, it will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the basic concepts and operating principles of the invention as broadly described. It should be recognized that, in the light of the above teachings, those skilled in the art can modify those specifics without departing from the invention taught herein. Having now fully set forth the preferred embodiments and certain modifications of the concept underlying the present invention, various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with such underlying concept. It is intended to include all such modifications, alternatives and other embodiments insofar as they come within the scope of the appended claims or equivalents thereof. It should be understood, therefore, that the invention may be practiced otherwise than as specifically set forth herein. Consequently, the present embodiments are to be considered in all respects as illustrative and not restrictive.
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A functional electrical stimulation step and stand system comprising two footplates (left and right) connected to a primary drive motor that cause the footplates to move in a reciprocal motion. The footplates are further connected to corresponding servos, which allow for control of the movement of the footplate with respect to an axis. system comprises an electrical stimulation control unit. The stimulation step and stand system further comprises a control unit that has electrical stimulation leads connected to electrodes that deliver an electrical impulse to a patient's muscles. In a further embodiment, the control unit has one or more wireless stimulators.
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BACKGROUND OF THE INVENTION
The present invention relates to a device for aligning printing plates on printing plate cylinders of rotary printing presses.
From U.S. Pat. No. 4,748,911 to Kobler there is known a device for the lateral register adjustment of a printing plate on a printing plate cylinder of a printing press. A turntable set wheel is arranged on the front side of the plate cylinder over which printing plate aligning stops are positionable on worm gear spindles. The pin of the set wheel can either have an inside threaded hole and an outside thread or only an outside thread.
In a first embodiment of the U.S. Pat. No. 4,748,911, two printing plate aligning stops can be laterally positioned. In a second embodiment of the U.S. Pat. No. 4,748,911, the printing plate aligning stops of two actuator sections connected with a coupling can be laterally positioned. Sensitive adjustment of individual printing plate alignment stops is difficult to accomplish. The positioning regions of the printing plate alignment stops are limited by the thread pitches and the thread section lengths.
SUMMARY OF THE INVENTION
It is an objective of the invention to optimize a device for the alignment of printing plates. It is a further objective of the present invention to compensate for web growth as a paper web travels through successive printing units.
According to the invention, an eccentric bolt, received on one hand by a ring-shaped adjustment element and on the other hand by a positionable aligning element, functions as an actuating means to relatively move the aligning element. An advantage in this solution is that the adjustment element, which is axially displaceable in an axial cylinder bore of a printing plate cylinder, can be fixed. When the adjustment element is fixed, precision adjustment of the aligning element is possible by movement of the eccentric bolt. The precision adjustment of the aligning element, relative to the adjustment element, can be made in such a way that the aligning element lies against the edge of a pre-punched receiving opening of a printing plate.
In one embodiment of the invention, the adjustment element is separated into a first wing and a second wing. The eccentric bolt has a head part, which engages a recess constructed in the first wing of the adjustment element. An eccentricity between a shaft of the eccentric bolt and the head part of the eccentric bolt determine an adjustment region through which the aligning element can be moved.
In one embodiment of the invention, a guidance mechanism guides relative movement between the aligning element and the adjustment element. The guidance mechanism includes parts which extend parallel to the rotational axis of the printing plate cylinder. In this manner, turning motion of the eccentric bolt and movement of the head part of the eccentric bolt connected therewith, can be converted into an axially directed displacement movement of the aligning element.
In one embodiment of the invention, a spreading screw is provided between the first wing and the second wing of the adjustment element. The first and second wings are provided with an elastic covering. When the spreading screw is rotated, the first and second wings of the adjustment element are pressed against the surfaces of a printing plate cylinder bore. This allows a factory-presetting of the adjustment element. The position of the adjustment element is variable if the corrections which can be achieved with precision adjustment are not sufficient.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will best be understood from the following description of an embodiment as illustrated in the accompanying drawings, in which:
FIG. 1 is a partial sectional view of a printing plate cylinder with an actuating shaft in an axial cylinder bore;
FIG. 2 is a cross-section view taken along the line 2--2 of FIG. 1;
FIG. 3 is a cross-section view taken along the line 3--3 of FIG. 1;
FIG. 4 is a view of an enlarged adjustment element; and
FIG. 5 is a view taken along line 5--5 in FIG. 4.
DESCRIPTION OF PREFERRED EMBODIMENT
A printing plate cylinder 10 (FIG. 1) is supported on 10 a cylinder journal 12 which is rotatably received in the side walls of a machine. The printing plate cylinder 10 is rotatable about an axis 13. The printing plate cylinder 10 has a cylindrical outer surface 14 and a plurality of axial cylinder bores 16. In a preferred embodiment, the printing plate cylinder 10 has two bores 16. Each bore 16 is located within the printing plate cylinder 10 and extends the axial length of the printing plate cylinder 10.
In the preferred embodiment, the printing plate cylinder 10 has two slots 20 (FIG. 2). Each slot 20 extends the axial length of the printing plate cylinder 10. A first slot 20 extends through the outer surface 14 and intersects with a first one of the bores 16. A second slot 20 extends through the outer surface 14 and intersects with a second one of the bores 16.
An actuating shaft 26 (FIG. 1, only one shown) is located in each of the two bores 16 and is elongate along an axis 27 which is parallel to the axis 13 of the printing plate cylinder 10. Each actuating shaft 26 is rotatably supported by a bearing 28 (only one shown) provided on the end of the printing plate cylinder 10. Each actuating shaft 26 has a longitudinally extending groove 30. A locking mechanism 32, which is not described herein, is arranged on each actuating shaft 26 to hold the respective actuating shaft 26 in the bore 16.
Associated with each actuating shaft 26 are a plurality of ring-shaped tensioning elements 34 and a plurality of generally ring-shaped adjustment elements 36. The tensioning elements 34 and the adjustment elements 36 are alternately spaced along the respective actuating shaft 26. Each of the tensioning elements 34 has a center bore 37 (FIG. 2) through which the respective actuating shaft 26 extends. Each tensioning element 34 has a key 38 which engages with the groove 30 of the respective actuating shaft 26. Each tensioning element 34 can be moved along the respective actuating shaft 26 in an axial direction.
When a respective tensioning element 34 is moved along the respective actuating shaft 26 the key 38 slides along the groove 30. Each tensioning element 34 is rotated upon rotation of the respective actuating shaft 26 due to the interconnection of the key 38 and groove 30. The tensioning element 34 can be provided with an elastic covering 39 for increased resilience and friction.
Each adjustment element 36 (FIG. 3) has a bore 41 through which the respective actuating shaft 26 extends. Each adjustment element 36 (FIGS. 4 and 5) is bifurcated to define first and second wings 40 and 42. A separating cut 43 and a slot 44 are located between the first wing 40 and the second wing 42. The cut 43 extends to intersect the bore 41 to define the first and second wings 40 and 42. Thus, the adjustment element 36 has a generally C-shape. The slot 44 extends radially from the bore 41 and increases the relative movability of the first and second wings 40 and 42.
The first wing 40 has a threaded bore 45 (FIG. 5), a threaded bore 46 and a circular recess 47. The first wing 40 also has a planar surface 48 and a groove 49 defined in the surface 48 which extends parallel to the axis 27 (FIG. 4). The second wing 42 has a blind hole 50.
A spreading screw 51 bridges the cut 43 between the first and second wings 40 and 42. The spreading screw 51 extends through the threaded bore 46 (FIG. 5) and is received in the blind hole 50. The spreading screw 51 has a head 52 for rotation of the spreading screw 51. When the spreading screw 51 is rotated, the first and second wings 40 and 42 relatively move. A clip 53 retains the spreading screw 51 on the first wing 40.
Each adjustment element 36 (FIG. 1) can be moved along the respective actuating shaft 26 in an axial direction. When a respective adjustment element 36 is located at a desired position relative to the respective actuating shaft 26 and bore 16, the spreading screw 51 (FIGS. 4 and 5) can be rotated to wedge the first and second wings 40 and 42 against the surfaces which define the bore 16 (FIG. 3). The positioning of the adjustment element 36 with respect to the actuating shaft 26 and the printing plate cylinder 10 provides a course adjustment. Each adjusting element 36 may have an elastic covering (not shown) to increase resilience and friction.
A register pin 56 (FIGS. 4 and 5) is associated with each adjustment element 36. For each respective adjustment element 36 and register pin 56, the register pin 56 engages the first wing 40. The register pin 56 has a projection 58 which extends parallel to the axis 27 and which engages the groove 49 on the first wing 40. The register pin 56 is displaceable in the axial direction along the groove 49. The projection 58 on the register pin 56 can slide along the groove 49. Thus, precision adjustment can be performed individually on each register pin 56 relative to the actuating shaft 26 and the printing plate cylinder 10.
Each register pin 56 (FIG. 5) has a bore 60 and a bore 62. Received within the bore 60 of the register pin 56 and the circular recess 47 of the adjustment element 36 is an eccentric bolt 64. The eccentric bolt 64 has a circular shaft 66 located in the bore 60 and an eccentric head part 68 located in the circular recess 47. The head part 68 is rotated upon rotation of the circular shaft 66. Rotation of the eccentric head part 68 within the circular recess 47 causes the shaft 66 to move eccentrically and forces the register pin 56 to move relative to the adjustment element 36. However, the register pin 56 is constrained to axial movement by the interconnection of the projection 58 and groove 52.
A threaded screw 72 extends through the bore 62 of the register pin 56 and engages the threaded bore 45. The threaded screw 72 has a shaft 73 and a head 74. The bore 62 is oversized relative to the shaft 76 to permit movement of the register pin 56 relative to the threaded screw 72. The threaded screw 72 is rotated by way of the head 74 on its upper end. The screw 72 is rotatable to lock the register pin 56 relative to the adjustment element 36. A clip 75 retains the screw 72, and thus the register pin 56, with the adjustment element 36.
A plurality of printing plates 78 (FIGS. 2 and 3, only one shown) are arranged on the cylinder 10. Each printing plate 78 has a leading edge 80 and a trailing edge 82. In the preferred embodiment, there are two printing plates 78 arranged around the circumference of the printing plate cylinder 10 and four printing plates are positioned adjacent to each other along the axis 13 of the printing plate cylinder 10.
For each printing plate 78, the leading edge 80 is received and secured in one of the slots 20 of the printing plate cylinder 10. The printing plate 78 is guided (wound) over a portion of the outer surface 14 of the printing plate cylinder 10. The trailing edge 82 is located in a second one of the slots 20. The trailing edge 82 extends into the second slot 20 adjacent the tensioning elements 34 and the adjusting elements 36.
The tensioning elements 34 engage the trailing edge 82. To tighten the printing plate 78 about the printing plate cylinder 10, the actuating shaft 26 located in the second slot 20 is rotated (counterclockwise as shown in FIG. 2) to rotate the tensioning elements 34. Rotation of the tension elements 34 draws the trailing edge 82 further into the second slot 20.
Each printing plate 78 has registration engagement portions, i.e. openings (not shown), into which the respective register pins 56 extends. Thus, the register pins 56 are aligning elements for the respective printing plate 78. The printing plate 78 is fixed in its position by fixing the adjustment elements 36 and the register pins 56 into respective positions so that the surfaces of the register pin 56 engage against the edges of the opening in the printing plate 78. Fixing of each adjustment element 36 is done by turning the spreading screw 51, which spread the first and second wings 40 and 42 and wedge the adjustment element 36 in the respective bore 16. Fixing of the register pin 56 takes place by rotating the threaded screw 72.
Due to the fact that a web to be printed receives a considerable amount of moisture and ink while passing the successive units, the web tends to expand, especially in the direction along the axis. This fan-out phenomenon can be compensated for by moving the register pins 56 accordingly. For this purpose, each eccentric bolt 64 is laterally adjustable within a range along the respective register pin 56. Adjustment is done when the printing plate cylinder 10 is stationary and accomplished by loosening the threaded screw 72 and rotating the eccentric bolt 64.
The lateral adjustment to compensate for web growth depends upon the number of printing units a web has to pass. It is obvious that the amount of lateral adjustment in the last printing unit is greater because the web has received a greater amount of moisture and ink and, therefore, has expanded considerably in the lateral direction. Whereas the amount of lateral adjustment due to web expansion in the earlier printing units will be considerably less. The register pins 56 can be moved laterally to the left or right, depending upon the direction in which the precision adjustment is necessary, e.g., either the right side edge or the left side edge of the printing plate 78 needs to be moved. All of the printing plates 78 which are received on the printing plate cylinder 10 can be handled in this way. The correct position of the register pins 56 can be marked at the edge of the respective slots 20 for certain formats which need to be printed often. Thus, a rough setting of the adjustment element 36 can be effected by aligning with the marks. Precision adjustment takes place through the axial movement of the register pins 56, so that quick adjustment can be made.
From the above description of the invention, those skilled in the art will perceive improvements, changes and modifications. Such improvements, changes and modifications within the skill of the art are intended to be covered by the appended claims.
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The invention relates to a device for the aligning of printing plates (78) on a printing plate cylinder (10) for a rotary printing press. At least one bore (16) extends through the printing plate cylinder (10) in an axial direction. A movable actuating shaft (26) is disposed in the bore (16). Located in the shaft (26) are a plurality of ring-shaped tensioning and adjustment elements which are spaced apart from one another. The adjustment elements (36) have movable aligning elements/register pins (56) arranged thereon. The invention is characterized in that, for at least one adjustment element (36), an eccentric pin (21) extends between the adjustment element (15) and the register pin (19). The eccentric pin (21) is rotatable to move the register pin (19) along the adjustment element (15).
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CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. application Ser. No. 13/039,446, entitled METHODS AND APPARATUS FOR PROVIDING HYPERVISOR LEVEL DATA SERVICES FOR SERVER VIRTUALIZATION, filed on Mar. 3, 2011 by inventor Ziv Kedem, which claims priority benefit of U.S. Provisional Application No. 61/314,589, entitled METHODS AND APPARATUS FOR PROVIDING HYPERVISOR LEVEL DATA SERVICES FOR SERVER VIRTUALIZATION, filed on Mar. 17, 2010 by inventor Ziv Kedem.
FIELD OF THE INVENTION
[0002] The present invention relates to virtual server computing environments.
BACKGROUND OF THE INVENTION
[0003] Data center virtualization technologies are now well adopted into information technology infrastructures. As more and more applications are deployed in a virtualized infrastructure, there is a growing need for recovery mechanisms to support mission critical application deployment, while providing complete business continuity and disaster recovery.
[0004] Virtual servers are logical entities that run as software in a server virtualization infrastructure, referred to as a “hypervisor”. Examples of hypervisors are VMWARE® ESX manufactured by VMware, Inc. of Palo Alto, Calif., HyperV manufactured by Microsoft Corporation of Redmond, WA, XENSERVER® manufactured by Citrix Systems, Inc. of Fort Lauderdale, Fla., Redhat KVM manufactured by Redhat, Inc. of Raleigh, N.C., and Oracle VM manufactured by Oracle Corporation of Redwood Shores, Calif. A hypervisor provides storage device emulation, referred to as “virtual disks”, to virtual servers. Hypervisor implements virtual disks using back-end technologies such as files on a dedicated file system, or raw mapping to physical devices.
[0005] As distinct from physical servers that run on hardware, virtual servers run their operating systems within an emulation layer that is provided by a hypervisor. Although virtual servers are software, nevertheless they perform the same tasks as physical servers, including running server applications such as database applications, customer relation management applications and MICROSOFT EXCHANGE SERVER®. Most applications that run on physical servers are portable to run on virtual servers. As distinct from virtual desktops that run client side applications and service individual users, virtual servers run applications that service a large number of clients.
[0006] As such, virtual servers depend critically on data services for their availability, security, mobility and compliance requirements. Data services include inter alia continuous data protection, disaster recovery, remote replication, data security, mobility, and data retention and archiving policies.
[0007] Conventional replication and disaster recovery systems were not designed to deal with the demands created by the virtualization paradigm. Most conventional replication systems are not implemented at the hypervisor level, with the virtual servers and virtual disks, but instead are implemented at the physical disk level. As such, these conventional systems are not fully virtualization-aware. In turn, the lack of virtualization awareness creates an operational and administrative burden, and a certain degree of inflexibility.
[0008] It would thus be of advantage to have data services that are fully virtualization-aware.
SUMMARY OF THE DESCRIPTION
[0009] Aspects of the present invention relate to a dedicated virtual data service appliance (VDSA) within a hypervisor that can provide a variety of data services. Data services provided by the VDSA include inter alia replication, monitoring and quality of service. The VDSA is fully application-aware.
[0010] In an embodiment of the present invention, a tapping filter driver is installed within the hypervisor kernel. The tapping driver has visibility to I/O requests made by virtual servers running on the hypervisor.
[0011] A VDSA runs on each physical hypervisor. The VDSA is a dedicated virtual server that provides data services; however, the VDSA does not necessarily reside in the actual I/O data path. When a data service processes I/O asynchronously, the VDSA receives the data outside the data path.
[0012] Whenever a virtual server performs I/O to a virtual disk, the tapping driver identifies the I/O requests to the virtual disk. The tapping driver copies the I/O requests, forwards one copy to the hypervisor's backend, and forwards another copy to the VDSA.
[0013] Upon receiving an I/O request, the VDSA performs a set of actions to enable various data services. A first action is data analysis, to analyze the data content of the I/O request and to infer information regarding the virtual server's data state. E.g., the VDSA may infer the operating system level and the status of the virtual server. This information is subsequently used for reporting and policy purposes.
[0014] A second action, optionally performed by the VDSA, is to store each I/O write request in a dedicated virtual disk for journaling. Since all I/O write requests are journaled on this virtual disk, the virtual disk enables recovery data services for the virtual server, such as restoring the virtual server to an historical image.
[0015] A third action, optionally performed by the VDSA, is to send I/O write requests to different VDSAs, residing on hypervisors located at different locations, thus enabling disaster recovery data services.
[0016] The hypervisor architecture of the present invention scales to multiple host sites, each of which hosts multiple hypervisors. The scaling flexibly allows for different numbers of hypervisors at different sites, and different numbers of virtual services and virtual disks within different hypervisors. Each hypervisor includes a VDSA, and each site includes a data services manager to coordinate the VSDA's at the site, and across other sites.
[0017] Embodiments of the present invention enable flexibly designating one or more virtual servers within one or more hypervisors at a site as being a virtual protection group, and flexibly designating one or more hypervisors, or alternatively one or more virtual servers within one or more hypervisors at another site as being a replication target for the virtual protection group. Write order fidelity is maintained for virtual protection groups. A site may comprise any number of source and target virtual protection groups. A virtual protection group may have more than one replication target. The number of hypervisors and virtual servers within a virtual protection group and its replication target are not required to be the same.
[0018] There is thus provided in accordance with an embodiment of the present invention a cross-host multi-hypervisor system, including a plurality of host sites, each site including at least one hypervisor, each of which includes at least one virtual server, at least one virtual disk that is read from and written to by the at least one virtual server, a tapping driver in communication with the at least one virtual server, which intercepts write requests made by any one of the at least one virtual server to any one of the at least one virtual disk, and a virtual data services appliance, in communication with the tapping driver, which receives the intercepted write requests from the tapping driver, and which provides data services based thereon, and a data services manager for coordinating the virtual data services appliances at the site, and a network for communicatively coupling the plurality of sites, wherein the data services managers coordinate data transfer across the plurality of sites via the network.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The present invention will be more fully understood and appreciated from the following detailed description, taken in conjunction with the drawings in which:
[0020] FIG. 1 is a simplified block diagram of a hypervisor architecture that includes a tapping driver and a virtual data services appliance, in accordance with an embodiment of the present invention;
[0021] FIG. 2 is a simplified data flow chart for a virtual data services appliance, in accordance with an embodiment of the present invention;
[0022] FIG. 3 is a simplified block diagram of a virtual replication system, in accordance with an embodiment of the present invention;
[0023] FIG. 4 is a simplified block diagram of a cross-host multiple hypervisor system that includes data services managers for multiple sites that have multiple hypervisors, in accordance with an embodiment of the present invention;
[0024] FIG. 5 is a user interface screenshot of bi-directional replication of virtual protection groups, in accordance with an embodiment of the present invention;
[0025] FIG. 6 is a user interface screenshot of assignment of a replication target for a virtual protection group, in accordance with an embodiment of the present invention; and
[0026] FIG. 7 is an example an environment for the system of FIG. 4 , in accordance with an embodiment of the present invention.
LIST OF APPENDICES
[0027] Appendix I is an application programming interface for virtual replication site controller web services, in accordance with an embodiment of the present invention;
[0028] Appendix II is an application programming interface for virtual replication host controller web services, in accordance with an embodiment of the present invention;
[0029] Appendix III is an application programming interface for virtual replication protection group controller web services, in accordance with an embodiment of the present invention;
[0030] Appendix IV is an application programming interface for virtual replication command tracker web services, in accordance with an embodiment of the present invention; and
[0031] Appendix V is an application programming interface for virtual replication log collector web services, in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
[0032] Aspects of the present invention relate to a dedicated virtual data services appliance (VDSA) within a hypervisor, which is used to provide a variety of hypervisor data services. Data services provided by a VDSA include inter alia replication, monitoring and quality of service.
[0033] Reference is made to FIG. 1 , which is a simplified block diagram of a hypervisor architecture that includes a tapping driver and a VDSA, in accordance with an embodiment of the present invention. Shown in FIG. 1 is a hypervisor 100 with three virtual servers 110 , three virtual disks 120 , an I/O backend 130 and a physical storage array 140 . Hypervisor 100 uses a single physical server, but runs multiple virtual servers 110 . Virtual disks 120 are a storage emulation layer that provide storage for virtual servers 110 . Virtual disks 120 are implemented by hypervisor 100 via I/O backend 130 , which connects to physical disk 140 .
[0034] Hypervisor 100 also includes a tapping driver 150 installed within the hypervisor kernel. As shown in FIG. 1 , tapping driver 150 resides in a software layer between virtual servers 110 and virtual disks 120 . As such, tapping driver 150 is able to access I/O requests performed by virtual servers 110 on virtual disks 120 . Tapping driver 150 has visibility to I/O requests made by virtual servers 110 .
[0035] Hypervisor 100 also includes a VDSA 160 . In accordance with an embodiment of the present invention, a VDSA 160 runs on a separate virtual server within each physical hypervisor. VDSA 160 is a dedicated virtual server that provides data services via one or more data services engines 170 . However, VDSA 160 does not reside in the actual I/O data path between I/O backend 130 and physical disk 140 . Instead, VDSA 160 resides in a virtual I/O data path.
[0036] Whenever a virtual server 110 performs I/O on a virtual disk 120 , tapping driver 150 identifies the I/O requests that the virtual server makes. Tapping driver 150 copies the I/O requests, forwards one copy via the conventional path to I/O backend 130 , and forwards another copy to VDSA 160 . In turn, VDSA 160 enables the one or more data services engines 170 to provide data services based on these I/O requests.
[0037] Reference is made to FIG. 2 , which is a simplified data flow chart for a VDSA, in accordance with an embodiment of the present invention. Shown in FIG. 2 are an I/O receiver 210 , a hash generator 220 , a TCP transmitter 230 , a data analyzer and reporter 240 , a journal manager 250 and a remote VDSA 260 . Remote VDSA 260 resides on different physical hardware, at a possibly different location.
[0038] As shown in FIG. 2 , I/O receiver 210 receives an intercepted I/O request from tapping driver 150 . VDSA 160 makes up to three copies of the received I/O requests, in order to perform a set of actions which enable the one or more data services engines 170 to provide various services.
[0039] A first copy is stored in persistent storage, and used to provide continuous data protection. Specifically, VDSA 160 sends the first copy to journal manager 250 , for storage in a dedicated virtual disk 270 . Since all I/O requests are journaled on virtual disk 270 , journal manager 250 provides recovery data services for virtual servers 110 , such as restoring virtual servers 110 to an historical image. In order to conserve disk space, hash generator 220 derives a one-way hash from the I/O requests. Use of a hash ensures that only a single copy of any I/O request data is stored on disk.
[0040] An optional second copy is used for disaster recovery. It is sent via TCP transmitter 230 to remote VDSA 260 . As such, access to all data is ensured even when the production hardware is not available, thus enabling disaster recovery data services.
[0041] An optional third copy is sent to data analyzer and reporter 240 , which generates a report with information about the content of the data. Data analyzer and reporter 240 analyzes data content of the I/O requests and infers information regarding the data state of virtual servers 110 . E.g., data analyzer and reporter 240 may infer the operating system level and the status of a virtual server 110 .
[0042] Reference is made to FIG. 3 , which is a simplified block diagram of a virtual replication system, in accordance with an embodiment of the present invention. Shown in FIG. 3 is a protected site designated Site A, and a recovery site designated Site B. Site A includes a hypervisor 100 A with three virtual servers 110 A- 1 , 110 A- 2 and 110 A- 3 , and a VDSA 160 A. Site A includes two physical disks 140 A- 1 and 140 A- 2 . Site B includes a hypervisor 100 B with a VDSA 160 B. Site B includes two physical disks 140 B- 1 and 140 B- 2 . All or some of virtual servers 110 A- 1 , 110 A- 2 and 110 A- 3 may be designated as protected. Once a virtual server is designated as protected, all changes made on the virtual server are replicated at the recovery site.
[0043] In accordance with an embodiment of the present invention, every write command from a protected virtual server in hypervisor 100 A is intercepted by tapping driver 150 ( FIG. 1 ) and sent asynchronously by VDSA 160 A to VDSA 160 B for replication, via a wide area network (WAN) 320 , while the write command continues to be processed by the protected server.
[0044] At Site B, the write command is passed to a journal manager 250 ( FIG. 2 ), for journaling on a Site B virtual disk 270 ( FIG. 2 ). After every few seconds, a checkpoint is written to the Site B journal, and during a recovery one of the checkpoints may be selected for recovering to that point. Additionally, checkpoints may be manually added to the Site B journal by an administrator, along with a description of the checkpoint. E.g., a checkpoint may be added immediately prior to an event taking place that may result in the need to perform a recovery, such as a planned switch over to an emergency generator.
[0045] In addition to write commands being written to the Site B journal, mirrors 110 B- 1 , 110 B- 2 and 110 B- 3 of the respective protected virtual servers 110 A- 1 , 110 A- 2 and 110 A- 3 at Site A are created at Site B. The mirrors at Site B are updated at each checkpoint, so that they are mirrors of the corresponding virtual servers at Site A at the point of the last checkpoint. During a failover, an administrator can specify that he wants to recover the virtual servers using the latest data sent from the Site A. Alternatively the administrator can specify an earlier checkpoint, in which case the mirrors on the virtual servers 110 B- 1 , 110 -B- 2 and 110 B- 3 are rolled back to the earlier checkpoint, and then the virtual servers are recovered to Site B. As such, the administrator can recover the environment to the point before any corruption, such as a crash or a virus, occurred, and ignore the write commands in the journal that were corrupted.
[0046] VDSAs 160 A and 160 B ensure write order fidelity; i.e., data at Site B is maintained in the same sequence as it was written at Site A. Write commands are kept in sequence by assigning a timestamp or a sequence number to each write at Site A. The write commands are sequenced at Site A, then transmitted to Site B asynchronously, then reordered at Site B to the proper time sequence, and then written to the Site B journal.
[0047] The journal file is cyclic; i.e., after a pre-designated time period, the earliest entries in the journal are overwritten by the newest entries.
[0048] It will be appreciated by those skilled in the art that the virtual replication appliance of the present invention operates at the hypervisor level, and thus obviates the need to consider physical disks. In distinction, conventional replication systems operate at the physical disk level. Embodiments of the present invention recover write commands at the application level. Conventional replication systems recover write commands at the SCSI level. As such, conventional replication systems are not fully application-aware, whereas embodiment of the present invention are full application-aware, and replicate write commands from an application in a consistent manner.
[0049] The present invention offers many advantages.
[0050] Hardware Agnostic: Because VDSA 160 manages recovery of virtual servers and virtual disks, it is not tied to specific hardware that is used at the protected site or at the recovery site. The hardware may be from the same vendor, or from different vendors. As long as the storage device supports the iSCSI protocol, any storage device, known today or to be developed in the future, can be used.
[0051] Fully Scalable: Because VDSA 160 resides in the hypervisor level, architectures of the present invention scale to multiple sites having multiple hypervisors, as described hereinbelow with reference to FIG. 4 .
[0052] Efficient Asynchronous Replication: Write commands are captured by VDSA 160 before they are written to a physical disk at the protected site. The write commands are sent to the recovery site asynchronously, and thus avoid long distance replication latency. Moreover, only delta changes are sent to the recovery site, and not a whole file or disk, which reduces the network traffic, thereby reducing WAN requirements and improving recovery time objective and recovery point objective.
[0053] Control of Recovery: An administrator controls when a recovery is initiated, and to what point in time it recovers.
[0054] Near-Zero Recovery Point Objective (RPO): VDSA 160 continuously protects data, sending a record of every write command transacted at the protected site to the recovery site. As such, recovery may be performed within a requested RPO.
[0055] Near-Zero Recovery Time Objective (RTO): During recovery the mirrors of the protected virtual servers are recovered at the recovery site from VDSA 160 B, and synchronized to a requested checkpoint. In accordance with an embodiment of the present invention, during synchronization and while the virtual servers at the recovery site are not yet fully synchronized, users can nevertheless access the virtual servers at the recovery site. Each user request to a virtual server is analyzed, and a response is returned either from the virtual server directly, or from the journal if the information in the journal is more up-to-date. Such analysis of user requests continues until the recovery site virtual environment is fully synchronized.
[0056] WAN Optimization between Protected and Recovery Sites: In accordance with an embodiment of the present invention, write commands re compressed before being sent from VDSA 160 A to VDSA 160 B, with throwing used to prioritize network traffic. As such, communication between the protected site and the recovery site is optimized.
[0057] WAN Failover Resilience: In accordance with an embodiment of the present invention, data is cached prior to being transmitted to the recovery site. If WAN 320 goes down, the cached data is saved and, as soon as WAN 320 comes up again, the data is sent to the recovery site and both sites are re-synchronized.
[0058] Single Point of Control: In accordance with an embodiment of the present invention, both the protected and the recovery site are managed from the same client console.
[0059] As indicated hereinabove, the architecture of FIG. 1 scales to multiple sites having multiple hypervisors. Reference is made to FIG. 4 , which is a simplified block diagram of a cross-host multiple hypervisor system 300 that includes data services managers for multiple sites that have multiple hypervisors, in accordance with an embodiment of the present invention. The architecture of FIG. 4 includes three sites, designated Site A, Site B and Site C, the three sites being communicatively coupled via a network 320 . Each site includes one or more hypervisors 100 . Specifically, Site A includes three hypervisors, 100 A/ 1 , 100 A/ 2 and 100 A/ 3 , Site B includes two hypervisors, 100 B/ 1 and 100 B/ 2 , and Site C includes one hypervisor 100 C/ 1 . The sites have respective one or more physical disks 140 A, 140 B and 140 C.
[0060] The hypervisors are shown in system 300 with their respective VDSA's 160 A/ 1 , 160 A/ 2 , . . . , and the other components of the hypervisors, such as the virtual servers 110 and virtual disks 120 , are not shown for the sake of clarity. An example system with virtual servers 110 is shown in FIG. 7 , and described hereinbelow.
[0061] The sites include respective data services managers 310 A, 310 B and 310 C that coordinate hypervisors in the sites, and coordinate hypervisors across the sites.
[0062] The system of FIG. 4 may be used for data replication, whereby data at one site is replicated at one or more other sites, for protection. The solid communication lines 330 in FIG. 4 are used for in-site traffic, the dashed communication lines 340 are used for replication traffic between sites, and the dotted communication lines 350 are used for control traffic between data services managers.
[0063] Data services managers 310 A, 310 B and 310 C are control elements. The data services managers at each site communicate with one another to coordinate state and instructions. The data services managers track the hypervisors in the environment, and track health and status of the VDSAs 160 A/ 1 , 160 A/ 2 , . . . .
[0064] It will be appreciated by those skilled in the art that the environment shown in FIG. 4 may be re-configured by moving one or more virtual servers 110 from one hypervisor 100 to another, by moving one or more virtual disks 120 from one hypervisor 100 to another, and by adding one or more additional virtual servers 110 to a hypervisor 100 .
[0065] In accordance with an embodiment of the present invention, the data services managers enable designating groups of specific virtual servers 110 , referred to as virtual protection groups, to be protected. For virtual protection groups, write order fidelity is maintained. The data services managers enable designating a replication target for each virtual protection group; i.e., one or more sites, and one or more hypervisors in the one or more sites, at which the virtual protection group is replicated. A virtual protection group may have more than one replication target. The number of hypervisors and virtual servers within a virtual protection group and its replication target are not required to be the same.
[0066] Reference is made to FIG. 5 , which is a user interface screenshot of bi-directional replication of virtual protection groups, in accordance with an embodiment of the present invention. Shown in FIG. 4 are virtual protection groups 301 (“Exchange”), 302 (“WebApp”), 303 (“Dummy-R1”), 304 (“Windows 2003”) and 305 (Dummies-L”). Arrows 306 indicate direction of replication.
[0067] Reference is made to FIG. 6 , which is a user interface screenshot of assignment of a replication target for a virtual protection group, in accordance with an embodiment of the present invention. Shown in FIG. 6 is an entry 307 for designating a recovery host, and an entry 308 for designating a recovery datastore for virtual protection group 304 (“Windows 2003”) of FIG. 5 . Respective source and target datastores, [SAN ZeRTO-30] 309 A and [datastore1] 309 B, are shown as being paired.
[0068] More generally, the recovery host may be assigned to a cluster, instead of to a single hypervisor, and the recovery datastore may be assigned to a pool of resources, instead of to a single datastore. Such assignments are of particular advantage in providing the capability to recover data in an enterprise internal cloud that includes clusters and resource pools, instead of using dedicated resources for recovery.
[0069] The data services managers synchronize site topology information. As such, a target site's hypervisors and datastores may be configured from a source site.
[0070] Virtual protection groups enable protection of applications that run on multiple virtual servers and disks as a single unit. E.g., an application that runs on virtual servers many require a web server and a database, each of which run on a different virtual server than the virtual server that runs the application. These virtual servers may be bundled together using a virtual protection group.
[0071] Referring back to FIG. 4 , data services managers 310 A, 310 B and 310 C monitor changes in the environment, and automatically update virtual protection group settings accordingly. Such changes in the environment include inter alia moving a virtual server 110 from one hypervisor 100 to another, moving a virtual disk 120 from one hypervisor 100 to another, and adding a virtual server 110 to a hypervisor 100 .
[0072] For each virtual server 110 and its target host, each VDSA 160 A/ 1 , 160 A/ 2 , . . . replicates IOs to its corresponding replication target. The VDSA can replicate all virtual servers to the same hypervisor, or to different hypervisors. Each VDSA maintains write order fidelity for the IOs passing through it, and the data services manager coordinates the writes among the VDSAs.
[0073] Since the replication target hypervisor for each virtual server 110 in a virtual protection group may be specified arbitrarily, all virtual servers 110 in the virtual protection group may be replicated at a single hypervisor, or at multiple hypervisors. Moreover, the virtual servers 110 in the source site may migrate across hosts during replication, and the data services manager tracks the migration and accounts for it seamlessly.
[0074] Reference is made to FIG. 7 , which is an example an environment for system 300 , in accordance with an embodiment of the present invention. As shown in FIG. 7 , system 300 includes the following components.
Site A
[0075] Hypervisor 100 A/ 1 : virtual servers 110 A/ 1 - 1 , 110 A/ 1 - 2 , 110 A/ 1 - 3 .
Hypervisor 100 A/ 2 : virtual servers 110 A/ 2 - 1 , 110 A/ 2 - 2 , 110 A/ 2 - 3 .
Hypervisor 100 A/ 3 : virtual servers 110 A/ 3 - 1 , 110 A/ 3 - 2 , 110 A/ 3 - 3 .
Site B
[0076] Hypervisor 100 B/ 1 : virtual servers 110 B/ 1 - 1 , 110 B/ 1 - 2 , 110 B/ 1 - 3 .
Hypervisor 100 B/ 2 : virtual servers 110 B/ 2 - 1 , 110 B/ 2 - 2 , 110 B/ 2 - 3 .
Site C
[0077] Hypervisor 100 C/ 1 : virtual servers 110 C/ 1 - 1 , 110 C/ 1 - 2 , 110 C/ 1 - 3 , 110 C/ 1 - 4 .
[0078] As further shown in FIG. 7 , system 300 includes the following virtual protection groups. Each virtual protection group is shown with a different hatching, for clarity.
[0000] VPG 1 (shown with upward-sloping hatching)
[0079] Source at Site A: virtual servers 110 A/ 1 - 1 , 110 A/ 2 - 1 , 110 A/ 3 - 1
[0080] Replication Target at Site B: virtual servers 110 B/ 1 - 1 , 110 B/ 1 - 2 , 110 B/ 2 - 1
[0000] VPG 2 (shown with downward-sloping hatching)
[0081] Source at Site B: virtual servers 110 B/ 1 - 3 , 110 B/ 2 - 2
[0082] Replication Target at Site A: virtual servers 110 A/ 1 - 2 , 110 A/ 2 - 2
[0000] VPG 3 (shown with horizontal hatching)
[0083] Source at Site A: virtual server 110 A/ 3 - 3
[0084] Replication Target at Site B: virtual serer 110 B/ 2 - 3
[0085] Replication Target at Site C: virtual server 110 C/ 1 - 4
[0000] VPG 4 (shown with vertical hatching)
[0086] Source at Site A: virtual servers 110 A/ 1 - 3 , 110 A/ 2 - 3 , 110 A/ 3 - 2
[0087] Replication Target at Site C: virtual servers 110 C/ 1 - 1 , 110 C/ 1 - 2 , 110 C/ 1 - 3
[0088] As such, it will be appreciated by those skilled in the art that the hypervisor architecture of FIG. 1 scales to multiple host sites, each of which hosts multiple hypervisors. The scaling flexibly allows for different numbers of hypervisors at different sites, and different numbers of virtual services and virtual disks within different hypervisors.
[0089] The present invention may be implemented through an application programming interface (API), exposed as web service operations. Reference is made to Appendices I-V, which define an API for virtual replication web services, in accordance with an embodiment of the present invention.
[0090] In the foregoing specification, the invention has been described with reference to specific exemplary embodiments thereof. It will, however, be evident that various modifications and changes may be made to the specific exemplary embodiments without departing from the broader spirit and scope of the invention as set forth in the appended claims. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense.
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A cross-host multi-hypervisor system, including a plurality of host sites, each site including at least one hypervisor, each of which includes at least one virtual server, at least one virtual disk that is read from and written to by the at least one virtual server, a tapping driver in communication with the at least one virtual server, which intercepts write requests made by any one of the at least one virtual server to any one of the at least one virtual disk, and a virtual data services appliance, in communication with the tapping driver, which receives the intercepted write requests from the tapping driver, and which provides data services based thereon, and a data services manager for coordinating the virtual data services appliances at the site, and a network for communicatively coupling the plurality of sites, wherein the data services managers coordinate data transfer across the plurality of sites via the network.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a counter electrode used in an electrochromic device. More particularly, it relates to a counter electrode in which an optical property in visible region is not substantially changed though reversible change of ions and electrons is caused by controlling its electric field and it also relates to a transmissive electrochromic device using the same.
2. Description of Prior Arts
Heretofore, certain electrochromic devices using a tungsten oxide film have been proposed.
It has been illustrated that color centers are formed by the following equation by biasing the tungsten oxide film in negative
WO.sub.3 (colorless)+XM.sup.+ +xe.sup.- →M.sub.x WO.sub.3 (blue color)
wherein M + designates a proton, an alkali metal ion or silver ion.
Such electrochromic devices are classified into a liquid type and a solid type. In the former system, the display electrode faces the counter electrode and a liquid electrolyte is filled between them.
In the structures of the electrochromic devices, symmetric and asymmetric devices have been proposed. The symmetric device comprises a transparent substrate (1) having a transparent conductive film (2) and a transparent substrate (4) having a conductive film (5), electrochromic films (3), (6) which are respectively formed on the conductive films (2) or (5) and an electrolyte (7) which is kept between the pair of the substrates and is sealed by sealant (8), as shown in FIG. 1. The asymmetric device comprises an inactive electrode substance such as a metal and carbon as the counter electrode.
Now, the inactive electrode has been considered not to be enough in view of its life. It is usual to employ the symmetric device.
In the symmetric device, the tungsten oxide film is formed on the display electrode and the counter electrode. Accordingly, the tungsten oxide film of the counter electrode is the colored state even though no display is performed. In order to obstruct the coloring state from an observer, a masking material (9) has been required.
Accordingly, the electrochromic device using a counter electrode made of an amorphous tungsten oxide must be a reflective type device.
In the latter device, a display electrode faces a counter electrode and a solid insulating film which injects ions only is located between the electrodes.
A device shown in FIG. 2 comprises a transparent substrate (11) having a tungsten oxide film (13), an ion permeable insulating film (14) made of CaF 2 and a counter electrode (15) of gold film. Since the gold film is used as the counter electrode (15) of the device, its transmission is inferior. Moreover, any reversible process is not be given as the reaction of the counter electrode (15) whereby a gas is generated to shorten its life, disadvantageously.
A device shown in FIG. 3 comprises a transparent substrate (21) having a transparent conductive film (22), a tungsten oxide film (23), an ion permeable insulating film (24) made of RbAg 4 I 5 which transmits silver ions, and a counter electrode (25) of silver film.
In the device, the reaction of Ag→Ag + +e is caused on the counter electrode whereby balance of the charges can be maintained. However, RbAg 4 I 5 is not stable. Silver ions are discharged on the display electrode whereby it is disadvantageously deposited in dentrite form. Moreover, a size of silver ion is large whereby a response is disadvantageously slow.
A device shown in FIG. 4 comprises a transparent substrate (31) having a transparent conductive film (32), a tungsten oxide film (33), an ion permeable insulating film (34) of chromia and a counter electrode (35) of gold film.
In the device, protons derived from a small amount of water in the chromia are used as the carrier of charge. Since the gold film is used as the counter film, its transmission is disadvantageously low.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a counter electrode having improved reversibility and longer useful life in its current feeding.
It is another object of the present invention to provide a transmissive electrochromic device using said counter electrode.
The foregoing and other objects of the present invention have been attained by providing a counter electrode in which optical property in the visible region is not substantially changed though reversible change of ions and electrons is caused by a control of its electric field. In particularly, the objects have been attained by using a crystalline tungsten oxide having porous structure formed by a vacuum evaporation method in a vacuum degree of 5×10 -4 to 2×10 -3 torr on a transparent conductive film and a baking at 350° to 450° C.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of a conventional liquid type electrochromic device;
FIGS. 2 to 4 are respectively sectional views of conventional solid type electrochromic devices;
FIG. 5 is a sectional view a liquid type electrochromic device of the present invention;
FIG. 6 is a spectrography of an amorphous tungsten oxide;
FIG. 7 is a spectrography of a crystalline tungsten oxide;
FIGS. 8 to 11 are respectively, applications of the electrochromic device of the present invention;
FIG. 12 is a sectional view of a solid type electrochromic device of the present invention; and
FIG. 13 is a spectrography of the counter electrode of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The counter electrode of the present invention has characteristic that its optical changeable wavelength region is substantially out of the visible region and its optical change is not substantially observed in a state absorbing ions and electrons by controlling electric potential, and also has excellent reversibility.
The counter electrode of the present invention basically has the following properties.
(1) It has a porous structure for diffusing ions under the control of an electric potential.
(2) It has mobility so that electrons for compensating the charge of diffused ions are drifted to reach near ions.
(3) Color centers are formed by mutual action of mother lattice, ions and electrons.
(4) It has crystalline property so that electrons trapped in color centers can be non-localized in relatively high degree. The color centers have no visible absorption.
The counter electrode of the present invention will be illustrated by an example of tungsten oxide.
The tungsten oxide film can be formed by a conventional E.B. method or a resistance heating method in a conventional vacuum evaporation apparatus. It can be also formed by a conventional sputtering method. The condition for forming the fabrication of the film is depending upon kind of the method. In a vacuum evaporation method, the vacuum degree is preferably ranging from 1×10 -4 torr to 5×10 -3 torr especially ranging from 5×10 -4 torr to 2×10 -3 torr. In a sputtering method, the vacuum degree is preferably ranging from 3×10 -2 torr to 2×10 -1 torr. The film formed in such condition is porous and amorphous in its structure. The film formed by the vacuum evaporation is preferable for the purpose of the present invention, because it has more porous structure than that of the sputter method. The film just after forming has an electrochromic characteristic which is found for its amorphous film. When the film is baked at a desired temperature such as from 350° C. to 450° C. for the tungsten oxide film, the film is substantially crystallized and the electrochromic characteristic is substantially varied from the characteristic of the amorphous tungsten oxide film. The main region of optical change caused by injection of ions and electrons is shifted to the near infrared region. The optical change is not substantially caused in the visible region. The coloring and bleaching response speed and its reversibility in the application of voltage are remarkably superior to those of the former.
In the counter electrode of the present invention, the main wavelength region for optical change caused by injection of ions and electrons by the application of voltage is shifted to the near infrared region from that of the amorphous tungsten oxide film whereby its optical change is not substantially observed as the visible change. The reversible change in the application of voltage is perfect.
The counter electrode of the present invention has both characteristics of the easy ion injection and extraction which is substantially the same with that of the amorphous tungsten oxide and the optical property of the crystalline tungsten oxide film as described above. The counter electrode can be prepared by the heat-treatment (baking) followed by the vacuum evaporation method or the sputter method as described above. These methods are not critical. It is also possible to form a film having similar characteristic by forming the film on a heated substrated. The substance for the film is not only tungsten oxide but also a composition of tungsten oxide and an additive such as Ta 2 O 5 , MoO 3 and V 2 O 5 or a substance which reversibly injects and extracts ions and electrons between an ion containing layer and the conductive film by a control of electric potential whereby its optical property is changed.
The electrochromic device having the counter electrode will be illustrated.
When the counter electrode of the present invention is used in the liquid type electrochromic device, it is unnecessary to use a masking material whereby the structure of the electrochromic device can be simplified and it can be easily prepared. This is a transmissive electrochromic device whereby it is possible to illuminate from its reverse side to be easily read as display device. It is possible to impart coloring of its background by disposing a backboard.
FIG. 5 shows one embodiment of the transmissive electrochromic device of the present invention. An electrochromic film (43) is formed on a transparent substrate (41) having a transparent conductive film (42). The electrochromic film can be an amorphous tungsten oxide film formed by the conventional method such as E.B. vacuum evaporation method.
On the other hand, a counter electrode is prepared by forming a transparent conductive film (45) on a transparent substrate (44) and then, forming a crystalline tungsten oxide film on it.
The pair of the substrates are sealed by a sealant to give a predetermined space, and an electrolyte (47) is filled in the space. The electrolyte can be known one and preferably a solution prepared by dissolving a salt containing proton or a monovalent ion such as alkali metal ion, silver ion and thallium ion, in an organic solvent such as propylenecarbonate, acetonitrile, dimethylsulfoxide and N-methyl pyrrolidone.
When a voltage is applied to the electrochromic device of the present invention to give negative for the display electrode (42), ions and electrons are injected in the amorphous tungsten oxide film to cause the following reaction whereby blue color is imparted in the appearance of the device.
WO.sub.3 (amorphous)+xMe.sup.+ +xe.sup.- →Me.sub.x WO.sub.3 (amorphous)
FIG. 6 1 shows the spectrography of the injection state.
When the polarity is reversed to give negative for the counter electrode, the reverse reaction to the above-mentioned reaction, is caused whereby the blue color is changed to colorless.
FIG. 6 2 shows the spectrography of the extraction state.
On the other hand, in the counter electrode, the following reaction is performed to result injection and extraction of the charge equivalent to that of the display electrode, whereby the charges are balanced to be stable reaction.
WO.sub.3 (crystalline)+xMe.sup.+ +xe.sup.- →Me.sub.x WO.sub.3 (crystalline)
However, the optical change on the counter electrode is not visible whereby the device is colorless.
FIG. 7 1 shows the spectrography in the state before this reaction.
FIG. 7 2 shows the spectrography in the state after the reaction.
The ions and electrons are reversibly injected and entered in the counter electrode of the electrochromic device of the present invention, however, an optical change in the visible region is not caused. Accordingly, it is possible to illuminate by locating a light source (81) and a reflecting plate (82) behind the electrochromic device (80) as shown in FIG. 8. It is also possible to illuminate by locating a light (91) and a light scattering plate (92) behind the electrochromic device (90) as shown in FIG. 9. It is also possible to be a reflective electrochromic device by locating a light scattering reflective plate (101) such as paper and metal plate behind the electrochromic device (100) as shown in FIG. 10. It is also possible to improve displaying effect with a color of background by locating a color backboard (111) behind the electrochromic device (110) as shown in FIG. 11.
The solid type electrochromic device having the counter device of the present invention will be illustrated.
FIG. 12 shows one embodiment of the solid type transmissive electrochromic device of the present invention.
A transparent conductive film (122) such as indium oxide and tin oxide is formed on the transparent substrate (121) and then, an electrochromic film (123) is formed on it as a counter electrode. In the electrochromic film, reversible injection and extraction of anions and electrons for compensating the charges can be caused but its optical property in the visible region is not substantially changed.
An insulating film (124) is formed on the electrochromic film (123) as the counter electrode. In the insulating film, anions can be injected but electrons are not substantially injected.
The ion permeable insulating film (124) can be made of calcium fluoride, lead (II) fluoride, silicon oxide, chromia, β-alumina, lithium nitride, lithium aluminate, lithium silicate, lithium zinc gelmanate, lithium magnesium gelmanate, etc.
The solid type transmissive electrochromic device can be prepared by forming an electrochromic film (125) as a display electrode in which reversible injection and extraction of anions and electrons for compensating the charges can be caused and its optical property in the visible region is changed, and also a transparent conductive film (126) on the above-mentioned insulating film (124).
When the electrochromic film (125) as the display electrode is biased in negative, anions and electrons for compensating the charges are injected to form color centers in the combination of the mother lattice, the anions and the electrons.
The electrochromic film can be made of an oxide or a sulfide of a metal such as tungsten, rhenium, vanadium, niobium, tantalum, chromium, manganese and titanium, especially an amorphous film containing tungsten oxide.
In order to operate reversibly the solid type transmissive electrochromic device, it is necessary to inject anions and electrons for compensating the charge of the anions, in one of the electrochromic film (123) as the counter electrode or the electrochromic film (125) as the display electrode.
In view of the preparation, it is preferable to inject anions in the electrochromic film (123) as the counter electrode. The electrochromic film (123) as the counter electrode is formed on a transparent substrate (121) having the transparent conductive film (122). This is immersed in an electrolyte containing anions and a voltage is applied to inject the anions.
Referring to FIG. 13, transmission characteristic in the operation will be illustrated for one example of the electrochromic device prepared by using electrochromic film (123) of a crystalline tungsten oxide having porous structure in which Li ions and electrons are injected, as the counter electrode and using amorphous tungsten oxide film (125) as the display electrode.
FIG. 13 1 shows the spectrography of the electrocromic film (125) as the display electrode in the state of non-application of voltage.
FIG. 13 2 shows the spectrography of the electrochromic film (123) as the counter electrode. This is the transmissive electrocromic device.
When a voltage is applied to give negative for the display electrode and to give positive for the counter electrode, the following reaction is caused in the electrochromic film (123) as the counter electrode, to form free Li ions.
Li.sub.x WO.sub.3 →xLi.sup.+ +xe.sup.- +WO.sub.3
The following reaction is caused in the electrochromic film (125) as the display electrode, to form Li x WO 3 and to impart blue color.
xLi.sup.+ +xe.sup.- +WO.sub.3 →Li.sub.x WO.sub.3
FIG. 13 3 shows the spectrography in this state.
When a voltage is applied to give negative for the counter electrode and to give positive for the display electrode, the reverse reactions to the above-mentioned reactions are caused to be colorless in the device.
As described above, the reversible injection and extraction of electrons is resulted in both electrochromic films as the display electrode and as the counter electrode, whereby the balance of the charges is maintained to prevent deterioration.
The electrochromic device of the present invention can be used as a display device and also optical changeable glasses for a curtainless window, an antidazzling mirror for a car, a light quantity variable sunvisior and a light quantity variable glasses.
The present invention will be further illustrated by certain examples and references which are provided for purposes of illustration only and are not intended to be limiting the present invention.
EXAMPLE 1
In a vacuum evaporation apparatus equipped with a rotary pump and an oil diffusion pump, a transparent glass substrate coating a transparent conductive film was set. It was evacuated to 10 -6 torr and then, N 2 gas was leaked to reduce the vacuum degree to 6×10 -4 torr. The vacuum evaporation was started. A powdery tungsten oxide was used as a raw material. An electron gun having an accelerating voltage of 10 kV was used for heating it. Thus, a tungsten oxide film having a thickness of about 0.5μ was prepared (Sample 1).
Sample 1 was baked at 390° C. for 30 minutes in air and gradually annealed. According to an analysis of a structure, it was confirmed that the tungsten oxide film obtained by the baking was crystallized. (Sample 2)
Spectrographies of Sample 1 and Sample 2 were respectively measured by using a propylenecarbonate containing LiClO 4 at a concentration of 1 mole/liter as an electrolyte and passing current at a coulomb of 10 mc/cm 2 .
FIG. 6 shows spectrographies of Sample 1 having an amorphous tungsten oxide film 1 before and 2 after passing the current.
FIG. 7 shows spectrographies of Sample 2 having a crystalline tungsten oxide film of the present invention 1 before and 2 after passing the current.
In the case of Sample 2, the main region for optical changes caused by the absorption of ions and electrons is shifted to near infrared region. The optical change is not substantially caused in visible region.
Sample 1 was treated at a coulomb of 10 mC/cm 2 to be the colored state and used as one electrode. Sample 2 was used as a counter electrode. The pair of the electrodes were arranged to face each other in an electrolyte of propylenecarbonate containing LiClO 4 at a concentration of 1 mole/liter. An induced optical density resulted by applying voltage; its coloring and bleaching speed; and reversibilities of the coloring and bleaching speed and electrode reaction in its coloring and bleaching time were tested. When a voltage of 1.5 V was applied between the crystalline tungsten oxide film (negative) and the amorphous tungsten oxide film (positive), the color of the amorphous tungsten oxide in the colored state disappears and the color of the crystalline tungsten oxide was not substantially changed to be colorless transparent. The current meter showed the fact of en electrode reaction. The coulometer showed the fact transferring the charge at a coulomb of 10 mC/cm 2 . When the polarity was reversed, the amorphous tungsten oxide film was colored and the current was passed. The coulometer showed the fact transferring the charge at a coulomb of 10 mC/cm 2 . The response time was high enough and was substantially the same as the response time of the amorphous tungsten oxide in the combination of the amorphous tungsten oxide films.
EXAMPLE 2
In a vacuum evaporation apparatus equipped with a conventional electron gun, a tungsten oxide film having a thickness of about 0.5μ was formed on a glass substrate having a transparent conductive film in a vacuum degree of 2×10 -5 torr. The product was used as a display electrode. A tungsten oxide film having a thickness of about 1.0μ was formed on a glass substrate in a vacuum degree of 6×10 -4 torr by the same process and the product was baked at 390° C. for 20 minutes in air. The product was used as a counter electrode.
The pair of the electrodes were arranged to face each other and a spacer was held between them at their peripheral part to seal them. An electrolyte obtained by dissolving LiClO 4 in propylenecarbonate at a concentration of 0.5 M/liter, was filled in the sealed electrodes from an inlet and the inlet was sealed to prepare an electrochromic device. A voltage of 3.5 V was applied between the display electrode (negative) and the counter electrode (positive). The amorphous tungsten oxide film on the display electrode was changed to be blue color. When a voltage of 1.5 V was applied between the display electrode (positive) and the counter electrode (negative), the blue color of the display electrode disappears. The crystalline tungsten oxide film on the counter electrode was not substantially changed by observation. The switching was repeated in 1.5 V whereby the coloring and the bleaching of the tungsten oxide on the display electrode were repeated. The tungsten oxide on the counter electrode was not changed. The transmissive electrochromic device was obtained. Any change of the device was observed and the device was actuated after switching for 300,000 times.
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An improved counter electrode used in an electrochromic device is transmissive in both charge injection and extraction states and exhibits excellent reversibility whereby it is optimum as a counter electrode in a transmissive electrochromic device which is useful as a display device in its control of visible and infrared absorption by a window and the like.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is based on and hereby claims priority to International Application No. PCT/EP2010/067830 filed on Nov. 19, 2010 and German Application No. 10 2009 060 937.7 filed on Dec. 22, 2009, the contents of which are hereby incorporated by reference.
BACKGROUND
[0002] The invention relates to a process for coating a workpiece on which a layer is produced electrochemically.
[0003] A process of the type mentioned at the outset is described, for example, in DE 602 25 352 T2. This process makes it possible to coat the surface of a workpiece electrochemically, for example by brush plating. Here, a nonwoven, open-pored sponge or a brush is used as transferer in order to transfer an electrolyte onto the surface to be coated. There, a metallic material is deposited on the surface from the electrolyte by application of an electric potential between the substrate and an electrode arranged in the region of the transferer for the electrolyte.
[0004] From WO 2006/061081 A2, it is also known that electrochemical deposition of metal can also be carried out using ionic liquids which replace an aqueous electrolyte. The use of ionic liquids, i.e. salt melts, which are in liquid form in the range below 100° C., preferably even at room temperature, has the advantage that their use gives larger process windows for the deposition of metals which, owing to their position in the electrochemical series of metals, cannot be deposited or can be deposited only with difficulty by aqueous electrolytes. An example of such a metal is Ta. It should be noted that the metal ions deposited from the salt melt onto the surface to be coated have to be replaced by fresh metal ions introduced into the salt melt in order for the deposition process not to come to a halt. A method of keeping the concentration of metal ions constant is described, for example, in DE 43 44 387 A1.
SUMMARY
[0005] It is one possible object to improve an electrochemical coating process so that the electrochemically deposited layers display an inhomogeneous expansion behavior.
[0006] The inventors propose for a second material having a coefficient of thermal expansion α which differs from that of the first material to be applied to the workpiece using a thermal spraying process and subsequently being embedded in the layer by electrochemical coating. This embedding can be carried out in such a way that the zones still form part of the resulting surface of the coated component, so that embedding occurs only on the lateral flanks of the zones. As an alternative, it is also possible to embed the zones in the layer in such a way that they are fully enclosed by the first material. For the purposes of this discussion, zones are subvolumes of the layer whose lateral dimension (i.e. dimension viewed in the direction parallel to the surface to be coated) is greater than their thickness dimension (i.e. dimension measured perpendicular to the surface to be coated). This leads to the thermal expansion behavior of the zones being more noticeable in the lateral direction of the layer than perpendicular to this direction. This causes, according to the proposal, the inhomogeneous expansion behavior of the layer produced.
[0007] For example, the second material can have a greater coefficient of thermal expansion a than the first material. In this case, the expansion of the zones leads to additional compressive stresses being formed in the regions of the layer adjacent to the zones. These can be used for stabilizing the microstructure of the layer if this were to react to tensile stresses by, for example, formation of cracks.
[0008] An inhomogeneous expansion behavior of the layer, which can be matched to different structural requirements for the component to be coated, can advantageously be produced by a suitable combination of the first material and the second material and by suitable geometric configuration of the zones. The zones can also be produced from a material which has a lower coefficient of thermal expansion α than the first material. In this case, additional compressive stresses would be generated in the first material of the layer when the component bearing the layer is cooled. This could, for example, be advantageous when the first material of the layer tends to display cold embrittlement and therefore has to be protected from occurrence of tensile stresses at low temperatures.
[0009] In an advantageous embodiment, cold gas spraying is employed as thermal spraying process. This is a process in which the coating particles remain adhering to the surface primarily as a result of their high kinetic energy. It is therefore also referred to as kinetic spraying. The kinetic energy is generated by a cold gas injection nozzle, a convergent-divergent nozzle, in a gas jet, with heating of the particles not occurring or occurring to only a small extent. In this case, the increase in temperature is not sufficient, as in the case of other thermal spraying processes, to melt the particles. The advantage of the use of cold gas spraying is therefore that the integrity of the microstructure of the particles used is not impaired by the cold gas spraying. In addition, this process has the advantage that, particularly in the case of a soft electrochemically produced layer matrix of the previous coat, the particles penetrate into the layer, as a result of which better distribution of the particles in the layer formed is achieved.
[0010] In a further embodiment, the layer is produced in a plurality of coats by carrying out the thermal spraying process and electrochemical coating alternately a plurality of times. This makes it possible, as indicated at the outset, to produce a layer structure in which the zones are completely embedded in the layer, i.e. no proportion of them forms on the surface. This is particularly advantageous when the material of the zones has to be, for example, protected against corrosive attack. In addition, the complete embedding of the zones allows particularly effective transmission of tensile or compressive stresses into the surrounding microstructure matrix of the first material.
[0011] In a particular embodiment, the thermal spraying and electrochemical coating are carried out simultaneously but each at different places on the workpiece. This allows, advantageously, a particularly high efficiency to be achieved in coating of the workpiece. A prerequisite is that the workpiece has to be coated only partially and simultaneously (at different places) by each of the two coating processes. In the case of thermal spraying, this is necessary in any case because coating always occurs only at the point of impingement of the coating jet. In electrochemical coating, it is necessary to select a coating process in which partial coating of the component is possible, i.e. in which the entire component does not dip into the electrolyte. This is preferably possible when employing brush plating, with only the subregion of the workpiece which is in contact with the transferer of the electrolyte being electrochemically coated at a particular time.
[0012] Simultaneous coating of the workpiece by the two coating processes can particularly preferably be employed when a cylindrical body, in particular a working roller for roll mills, is coated as workpiece, with this being set into rotation about its central axis and electrochemical coating being carried out at one place on its circumference and thermal spraying being carried out at another place on its circumference. This can be effected, for example, by only part of the circumferential area of the cylindrical workpiece being dipped into the electrolyte. Uniform coating is then ensured by uniform rotation of the cylindrical workpiece by which the entire outer surface can be gradually coated. Thermal coating can be carried out in the region which does not dip into the electrolyte. Rotation of the roller is also very advantageous when employing brush plating. The transferer for brush plating then only has to be brought into contact with the workpiece, with relative motion between the workpiece and the transferer being brought about by the continual rotation of the cylindrical workpiece.
[0013] In a particular embodiment, an ionic liquid is used as electrolyte for electrochemical coating. This has the advantage that even relatively base metals can be deposited from a nonaqueous medium, namely the salt melt of ionic coating. Ionic liquids are organic liquids which are formed of a cation such as an alkylated imidazolium, pyridinium, ammonium or phosphonium ion and an anion such as simple halides, tetrafluoroborates or hexafluorophosphates, bi(trifluoromethylsulfonyl)imides or tri(pentafluoroethyl)trifluorophosphates.
[0014] Since ionic liquids also have a high electrochemical stability, it is advantageously possible to deposit, inter alia, Ti, Ta, Al and Si which cannot be deposited from aqueous electrolytes because of the strong evolution of hydrogen. Suitable metal salts, which are also mentioned in the abovementioned WO 2006/061081 A2, are, for example, halides, imides, amides, alkoxides and salts of monobasic, dibasic or polybasic organic acids, e.g. acetates, oxalates or tartrates. The metals which are to be electrochemically deposited are brought into the suitable ionic liquid by anodic dissolution. A soluble electrode is used as counterelectrode to the component to be coated. This soluble electrode is formed of the metal which is to be applied as a coating. As an alternative, the metal to be deposited can also be added as salt to the ionic liquid. Then, a platinum electrode, for example, can be used as counterelectrode to the substrate. In this case, it has to be ensured that the concentration of the metal ions to be deposited in the ionic liquid is maintained, which is described in more detail in, for example, the abovementioned DE 43 44 387 A1. In addition, the metals can also be deposited as nanocrystalline layers when using ionic liquids. For this purpose, suitable cations, e.g. pyrrolinium ions, which are surface-active and therefore act as grain refiners in electrochemical deposition have to be added to the ionic liquid. It is advantageous that the addition of wetting agents or brighteners can frequently be dispensed with under these conditions.
[0015] How zones can be formed geometrically is described in detail below.
[0016] In an embodiment, the zones can be distributed as island-like depots in a regular pattern on the workpiece. A lower limit to the size of these island-like depots is imposed purely by the gas jet of the cold gas spraying process employed producing an impingement spot having certain dimensions on the component to be coated. This gives the smallest possible size of the depot. If the depot is to be larger, the cold gas jet has to be conducted in a suitable way during production of the depot. It is advantageous to produce depots having a round base area, but other geometries can also be realized. The production of comparatively small depots is advantageous because a dense change between the first material and the second material in the layer can be realized thereby. Stress peaks in the microstructures of the first material and of the second material can in this way be kept low as soon as these are formed as a result of the inhomogeneous expansion behavior of the layer.
[0017] Another possibility is to arrange the zones as strips on the workpiece. This makes it possible to produce an inhomogeneous expansion behavior which differs not only in respect of the expansion behavior of the layer perpendicular to the surface of the workpiece but also in respect of the lateral expansion behavior in different directions in the layer.
[0018] As an alternative, it is also possible for the zones to be arranged as rectangles in a two-dimensional array on the workpiece.
[0019] It is particularly advantageous for the layer to be produced in the region of at least one zone on a sacrificial material, e.g. wax, which is removed to form a hollow space, for example by melting, after production of the layer. In this way, cantilever structures which, owing to their inhomogeneous expansion behavior, can be used as mechanical adjusting elements can advantageously be formed from the zones of the second material and the layer composite of the first material surrounding these zones. The driving force for actuation of the adjusting elements is accordingly temperature differences during operation of the coated component.
[0020] For example, it is possible for the zone formed by the second material together with the first material of the remaining layer to be configured so as to give a multilayer, cantilevered bending beam. At its one end, the bending beam is then joined to the remaining layer composite. Underneath the bending beam, there is the abovementioned hollow space, with the other end of the bending beam being freely movable. As a result of the different expansion behavior of the two materials, which are preferably arranged in two adjoining layers, the beam bends by the mechanism which is known, for example, from bimetallic strips. The adjusting element is realized in this way.
[0021] A bending beam configured in this way can be produced with its free end above, for example, an orifice in the surface of the workpiece. This orifice can, for example, serve for introduction of a cooling medium. The bending beam can be configured so that the orifice is opened only when a particular temperature is exceeded, so that the coolant is introduced only in the case of a threatening overheating of the component. A temperature-controlled valve is advantageously realized in this way. Throttling of the coolant flow can also be achieved.
[0022] In another embodiment, the zone as cantilevered beam is produced from the second material. This has a greater coefficient of thermal expansion α than the first material. The bending beam is joined at its one end to the remaining layer composite and its other end is at a defined spacing from the remaining layer composite. The beam formed in this way preferably has no component of the first material. This structure can, for example, be used as thermal switch. When the component is heated, the beam expands as a result of the greater coefficient of thermal expansion α of the beam and at a particular temperature bridges the defined distance to the remaining layer composite. This produces a contact which requires electrical conductivity of at least the second material and leads to a change in the electrical behavior of the layer. This can be measured and used as a switching signal. If the first material is an electric insulator, a suitable configuration of input leads, for example composed of the first material, also enables an electric switch to be realized by the beam.
[0023] In the case of components having an axis of rotation, which are preferably cylindrically symmetric, it is particularly advantageous for the parts of the layer provided with zones to alternate with parts of the layer without these zones in the circumferential direction relative to the axis of rotation. In this way, it is, as indicated above, advantageously possible to produce a compressive stress in the circumferential direction in the component owing to the inhomogeneous expansion behavior. This can be particularly advantageous when the component is unintentionally subjected to tensile stress in the zones in the peripheral region, for example because of high rotational speeds and the resulting centrifugal forces.
[0024] The process can be employed particularly advantageously for working rollers of a roll mill. These serve, inter alia, to transport the material to be rolled, e.g. a metal sheet, whose wall thickness, for example, is to be reduced by being conveyed between the working rollers. The working rollers of a roll mill are therefore subject to tremendous wear. This can be reduced by the coatings applied according to the proposal when particles of a hard material are preferably embedded in the zones. These can be, for example, oxides of Al, Co, Mg, Ti, Si or Zr, nitrides of Al, B or Si or carbides of B, Cr, Ti, Si or W or else carbonitrides. Carbon as graphite, diamond, DLC (diamond-like carbon) or glassy carbon or mixtures of all the materials mentioned can also be used. Particularly preferred hard materials are the following: TiC, B 4 C, Cr 3 C 2 , SiC, WC, TiN, MoB, TiB 2 , Al 2 O 3 , Cr 2 O 3 , TiO 2 . Particles of cemented hard metals (WC, TiC or TiN in a proportion of ≧80% by weight in a matrix of Co, Ni, Cr, Fe) can also be used.
[0025] The hard materials mentioned can be deposited together with particles of a matrix material as second material in the zones. The first material can be selected with a lower coefficient of thermal expansion than the second material in order to generate compressive stresses in the zones which, owing to the proportion of hard materials, have to be reinforced against the occurrence of tensile stresses in the microstructure on heating of the roller surface. Comparatively high concentrations of hard material particles can then be realized in the zones.
[0026] The hard materials used in the zones of the layer produced firstly advantageously reduce the abrasion thereof, so that the wear resistance thereof increases. Furthermore, the hard materials also serve the purpose of increasing the surface roughness of the layer, which is necessary to transmit the torque of the working rollers to the metal sheet to be rolled. If the hard materials are provided by the multilayer structure of the roller over the entire layer thickness, it is also advantageously ensured that the surface roughness of the roller is maintained even in the event of abrasion of the layer with progressive wear as a result of continual exposure of fresh hard material particles. This means that a component which fully meets the surface roughness requirements over its entire intended life is advantageously created.
[0027] The advantages of the process will be summarized once more at this point. Electrochemical deposition of even electrochemically base metals such as Ti, Ta, Si, Al or Mg is possible when an ionic liquid is selected as electrolyte. Inexpensive deposition is possible, in particular by selection of the brush plating process since comparatively rapid layer growth can be achieved here. Introduction of particles into the zones being formed from the second material is possible and high particle concentrations in the layer can be achieved. The process is also partially applicable to large workpieces since these do not have to be dipped into an electrolyte in the case of brush plating. In particular, the process can also be employed for repair purposes since the coating system (including a cold gas spray gun and a transferer for brush plating) is transportable and can therefore also be used, for example, at the place of use of the workpiece to be repaired.
First Example
[0028] Surface cleaning and activation is firstly carried out on the workpiece to be coated. This can be carried out, for example, by brush cleaning using an alkaline and/or cyanide-containing electrolyte and brush etching using an acidic electrolyte, e.g. hydrochloric acid or sulfuric acid. The first coating step in which a ductile base material such as nickel or nickel-cobalt is deposited as first material is then carried out. This process is carried out by brush plating. As electrolyte, it is possible to use, for example, a Watts electrolyte. The transferer for brush plating, which can be a felt or sponge soaked with the electrolyte, is moved over the surface to be coated. An anode in the form of a rod, wire braid or composed of spheres can be present in the transferer. The material of the anode is either the base material of the layer to be deposited, in which case this then dissolves and has to be replaced at regular intervals, or an inert anode, for example a platinum anode.
[0029] Depending on the workpiece geometry, the further coating step can be carried out subsequently to electrochemical coating or simultaneously at another place. Here, zones of a second material having a different coefficient of thermal expansion are applied by thermal spraying, preferably cold gas spraying, with the particles intermeshing mechanically with the surface and therefore adhering. In cold gas spraying, the surface is advantageously subject to barely any thermal stress. This can therefore immediately be fed once again to the electrochemical coating step. A tight sequence of electrochemical and thermal coating steps can be realized. As a result, rapid layer buildup is possible, which advantageously improves the economics of the parts produced.
Second Example
[0030] Coating is firstly carried out in a nonaqueous electrolyte. Surface cleaning and activation of the workpiece to be coated is carried out in the above-described way by brush cleaning and brush etching. After drying at 100° C., the first coating step, in which a metallic layer of, for example, titanium is deposited, is carried out. This process is carried out by brush plating. The electrolyte used for the deposition of titanium as first material is 1-butyl-3-methylimidazolium tetrafluoroborate in which titanium tetrafluoroborate is dissolved as ion carrier. A felt or sponge is soaked with this electrolyte and moved over the area to be coated on the component. The transferer formed by the felt or sponge is equipped with an electrode in the above-described manner. This can be formed of titanium or an inert material such as platinum.
[0031] Depending on the workpiece geometry, the second coating step can be carried out alternately with electrochemical coating or else simultaneously at a place at which electrochemical coating is not being carried out at the particular time. Here, zones composed of, for example, aluminum as second material are produced by the abovementioned cold gas spraying. In the subsequent electrochemical treatment step, the zones are then incorporated into the metal matrix in the above-described manner by electrochemically depositing titanium again.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] These and other objects and advantages of the present invention will become more apparent and more readily appreciated from the following description of the preferred embodiments, taken in conjunction with the accompanying drawings of which:
[0033] FIG. 1 is an example of the proposed process for coating a workpiece,
[0034] FIGS. 2 and 3 show a movement pattern as can be traced by the cold gas spraying nozzle as per FIG. 1 and
[0035] FIGS. 4 to 11 show layer structures which can be produced by examples of the process.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0036] Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout.
[0037] In the example of the proposed process as per FIG. 1 , a roller-shaped workpiece 11 is provided with an antiwear layer. The workpiece 11 is mounted so as to be rotatable about its central axis 12 , with the axis of rotation 13 being identical to the central axis 12 . A bearing 14 is schematically shown, with the workpiece 11 being turned at constant speed by a drive (not shown) during coating.
[0038] FIG. 1 shows a plan view of the workpiece 11 from above looking vertically downward. During coating, a transferer 15 which is formed of a sponge having open pores 16 is brought into contact with the workpiece from the one side. An electrolyte is applied by this via a feed system 17 in a manner not shown in more detail to the surface 18 of the workpiece which moves along under the transferer. Electrochemical coating takes place during this process, and the workpiece 11 and the transferer are for this purpose connected to a voltage source 19 .
[0039] At the same time, cold gas spraying takes place on the opposite side of the workpiece. A cold gas spraying nozzle 20 is for this purpose directed at the surface 18 of the workpiece and moved stepwise over the surface approximately in the direction of the axis of rotation 13 . At the pause locations 26 (shown in FIG. 3 ) of the cold gas jet, small depots 27 (shown in FIG. 4 ) of a material having a coefficient of expansion other than that of the layer material applied by electrochemical coating are formed. When the cold gas jet is moved between the pause locations, individual particles from the cold gas jet 21 remain adhering to the surface and are subsequently incorporated into the layer matrix in the layer then formed at the transferer 15 due to rotation of the workpiece. However, these have a negligible effect compared to the depots 27 because of their small size.
[0040] It can also be seen in FIG. 1 that a movement region 22 of the cold spraying nozzle 20 is somewhat smaller than the length of the workpiece since, for example, in the case of working rollers of roll mills as workpieces to be coated each end face region does not participate in the rolling process and is therefore also not subjected to the severe wear stress. If the movement region 22 of the cold gas spraying nozzle 20 is selected so that it does not extend to the edge of the workpiece to be coated, this has advantages in terms of carrying out the process. The movement pattern of the cold spraying nozzle is shown in FIG. 2 . This is a path corresponding to a figure eight, with the continual movement 24 of the workpiece owing to the rotation being taken into account. A line 25 as per FIG. 3 is traced on the surface 18 of the workpiece 11 due to the figure eight-shaped path, so that uniform loading of the surface with particles occurs. The pause locations 26 of the cold gas jet, which lead to a buildup of depots 27 in the layer material 28 as shown in FIG. 4 having a chessboard-like layer structure are also shown in FIG. 3 .
[0041] FIG. 4 shows a plan view onto the layer surface. It can be seen that the depots 27 are embedded in the first material 28 of the layer so as to form part of the layer surface. In FIG. 5 , on the other hand, the depots 27 are completely surrounded by the material 28 of the layer. This can be achieved by an electrochemical coating step with the first material 28 of the layer being carried out after application of the depots 27 without the second material being applied once more. A layer 29 formed in this way thus has three coats 30 of which only the middle coat is provided with the depots 27 .
[0042] FIG. 6 once again shows the layer surface with exposed strips 31 of the second material which are embedded at the side flanks in the first material 28 . Another embodiment is obtained when rectangles 32 are produced instead of the strips 31 , as is shown in FIG. 7 . These are also exposed at the top, so that they can be seen in the layer surface, while their sides are embedded in the first material.
[0043] FIG. 8 shows how a bending beam 33 can be integrated into the layer 29 on the component 11 . To ensure that this can be produced in a cantilever fashion, wax as sacrificial material 34 is applied in a prescribed shape to the component 11 so that the sacrificial material also closes an orifice 35 in the component 11 and thus prevents this orifice from being closed by the coating process. Above the sacrificial material 34 , the first material 28 is firstly deposited electrochemically; for this purpose, the sacrificial material has to be provided with an electrically conductive initial layer. A zone 36 is subsequently produced on the first material by cold gas spraying and the flanks 36 a thereof are subsequently embedded in the first material 28 . To prevent the zone 36 itself from being coated by the first material 28 , this zone is electrically insulated (for example by a protective surface coating). In this way, a two-layer composite which bends in the event of temperature changes owing to the inhomogeneous expansion behavior and can in this way also close the orifice 35 is formed at least in the middle part of the bending beam 33 . To ensure this bending and closure function the sacrificial material 34 is removed by, for example, melting after the bending beam 33 has been produced.
[0044] Another example can be seen in FIGS. 9 and 10 ; here, the section planes of the other figures are drawn in appropriately (section X-X corresponds to the section plane in FIG. 10 and section IX-IX corresponds to the section plane in FIG. 9 ). FIG. 9 shows a beam 37 which is integrated into the layer 29 . One end of the beam 37 , which is formed entirely of the second material, is embedded in the first material 28 (cf. FIG. 10 ) and thus fixed in the region of the layer 29 . A hollow space is defined by the sacrificial material 34 and leads to the beam 37 being arranged in a cantilever fashion in the layer.
[0045] Heating causes the beam 37 to expand and when a sufficient increase in length has occurred, a spacing a is bridged so that the beam 37 contacts a cross strut 38 made of the first material 28 . This likewise spans, in a cantilever fashion, an equilibration orifice 39 , so that on further heating and expansion of the beam 37 , the cross strut 38 can deform elastically. It can be seen from FIG. 10 that the sacrificial material underneath the beam 37 and the cross strut 38 also ensures that there is no connection to the component 11 . After production of the layer 29 is complete, the sacrificial material has to be removed.
[0046] In addition, FIG. 9 shows the places 40 at which electrodes could contact the surface in order to detect a change in the electrical resistance in the case of contact of the beam 37 with the cross strut 38 . This can, in particular, be measured when the beam 37 has a lower electrical resistance than the first material 28 .
[0047] FIG. 11 depicts a component 11 which is configured as a shaft and is shown in cross section. The layer is formed of the first material 28 , with strips 31 running in the axial direction being provided in the layer. Viewed from the outside, the component 11 thus has a layer pattern as is shown in FIG. 6 .
[0048] The invention has been described in detail with particular reference to preferred embodiments thereof and examples, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention covered by the claims which may include the phrase “at least one of A, B and C” as an alternative expression that means one or more of A, B and C may be used, contrary to the holding in Superguide v. DIRECTV, 69 USPQ2d 1865 (Fed. Cir. 2004).
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In a method for coating a work piece, a layer is electrochemically produced from a first material. In order to generate an inhomogeneous expansion behavior of the layer, a thermal spraying, in particular a cold gas spraying, achieves that specific zones are created in the layer from a material having a different thermal expansion behavior. These zones expand more laterally than in the direction of the layer thickness so that directed internal stresses occur in the layer upon heating or cooling of the component, which can be specifically utilized depending on the design conditions of the component.
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CROSS REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority from U.S. Provisional Patent Application Ser. No. 60/729,631, filed Oct. 24, 2005.
FIELD OF THE INVENTION
[0002] The present invention relates to chemical wipes, to the use of the wipes to treat various surfaces; to packages containing the wipes and to kits containing packages of different chemical wipes designed to be used in combination with one another on various surfaces.
BACKGROUND OF THE INVENTION
[0003] Wipes that are treated with various chemicals such as cleaning agents and bactericides are well known in the art. The wipes can be used to treat various surfaces for cleaning and to impart certain properties such as anti-bacterial protection.
[0004] It is also known that various optical surfaces such as eyewear and display devices are susceptible to dirt collection and smudging, particularly when the surfaces have an anti-reflective coating thereon. The dirt smudges may be removed or cleaned by wiping with a cloth containing a cleaning agent, but such removal is usually temporary and the surfaces are prone to repeated dirt collection and smudging which requires repeated cleaning.
[0005] Therefore, there is a need to treat such surfaces in a manner to create some permanency in the treatment such that the tendency for repeated dirt collection and smudging is reduced and/or repeated smudging can be easily removed, for example, by simply wiping with a soft cloth.
[0006] The present invention addresses this problem and provides a chemical wipe that can be used to treat optical surfaces and alter the properties of the surfaces such that the smudging problem is significantly alleviated. The wipes of the present invention can also be used to treat other surfaces where it is desired to alter the property of the surface, for example, to make the surfaces more hydrophilic or hydrophobic.
SUMMARY OF THE INVENTION
[0007] The present invention provides for the following:
[0008] A method of treating a substrate surface comprising:
(a) contacting the surface, directly or through an intermediate organometallic layer with a wipe treated with an organophosphorus acid, or derivative thereof; (b) moving the wipe across the surface to transfer a film of the organophosphorus acid or derivative thereof to the surface or to the intermediate layer.
[0011] When the substrate surface is treated directly with the wipe, the substrate can optionally contain a hydrophobic coating that has lost its effectiveness on its surface.
[0012] A method of treating a substrate surface comprising:
(a) contacting the surface through an intermediate organometallic layer with a wipe treated with an organic acid or derivative thereof; (b) moving the wipe across the organometallic layer to transfer a film of the organic acid or derivative thereof to the organometallic layer.
[0015] Optionally, an organic acid such as an organophosphorus acid can be applied to the organometallic layer, typically by spraying. The substrate surface can optionally contain a hydrophobic coating that has lost its effectiveness.
[0016] A package comprising a material treated with an organophosphorus acid or derivative thereof dissolved or dispersed in a diluent and in a container substantially impervious to the diluent.
[0017] A package comprising a material treated with an organometallic compound in a substantially moisture-impervious container.
[0018] A kit useful for treating a surface to alter its physical properties comprising:
(a) a package comprising a material treated with an organometallic compound in a substantially moisture-impervious container; (b) a package comprising an organic acid or derivative thereof dissolved or dispersed in a diluent in a container substantially impervious to the diluent.
DETAILED DESCRIPTION
[0021] The wipes of the present invention typically comprise a flexible porous material usually in sheet form treated with the organometallic compound, and in one embodiment and with the organic acid, as the case may be. By the term “wipe” is meant a material treated with a substance and used to apply the substance to a surface by hand rubbing. Most often, the wipe is held by the fingers and thumb of the hand.
[0022] The material associated with the wipe is generally an absorbent or adsorbent material, for example, a woven, nonwoven or knit fabric, a foam or a sponge or other structure suitable for absorbing or adsorbing and holding the organophosphorus acid and the organometallic compound, as the case may be, and transferring by rubbing such substance to the surface being treated.
[0023] The nonwovens may include nonwoven fibrous sheet materials that include meltblown, coform, air-laid, spunbond, wet laid, bonded-carded web materials, hydroentangled (also known as spunlaced) materials, and combinations thereof. These materials can comprise synthetic or natural fibers or combinations thereof.
[0024] Woven materials, such as cotton fibers, cotton/nylon blends, or other textiles may also be used herein. Regenerated cellulose, polyurethane foams, and the like, which are used in making sponges, may also be suitable for use herein.
[0025] The organic acid that may be used to treat the wipes includes derivatives thereof. Derivatives are materials that perform similarly as the acid precursors and include acid salts such as metal salts, for example, sodium and potassium salts, acid esters such as lower alkyl esters containing from 1 to 4 carbon atoms, and acid complexes. The organo group of the acid may be a monomeric, oligomeric or polymeric group. The organic acid may be a carboxylic acid, a sulfonic acid and preferably a phosphorus acid.
[0026] Examples of monomeric carboxylic and sulfonic acids are
[0000] R—COOR′ and R—SO 2 —OR′
[0000] where R is a hydrocarbon or substituted hydrocarbon radical having a total of 1 to 30, preferably 6 to 20 carbon atoms and R′ is H, a metal or lower alkyl. Preferably at least a portion of R′ is H.
[0027] Examples of monomeric phosphoric acids are compounds or a mixture of compounds having the following structure:
[0000] (RO) x —P(O)—(OR′) y
[0000] wherein x is 1-2, y is 1-2 and x+y=3, R preferably is a radical having a total of 1-30, preferably 6-18 carbons, where R′ is H, a metal such as an alkali metal, for example, sodium or potassium or lower alkyl having 1 to 4 carbons, such as methyl or ethyl. Preferably, a portion of R′ is H. The organic component of the phosphoric acid (R) can be aliphatic (e.g., alkyl having 2-20, preferably 6-18 carbon atoms) including an unsaturated carbon chain (e.g., an olefin), or can be aryl or aryl-substituted moiety.
[0028] Example of monomeric phosphonic acids are compounds or mixture of compounds having the formula:
[0000]
[0000] wherein x is 0-1, y is 1, z is 1-2 and x+y+z is 3. R and R″ preferably are each independently a radical having a total of 1-30, preferably 6-18 carbons. R′ is H, a metal, such as an alkali metal, for example, sodium or potassium or lower alkyl having 1-4 carbons such as methyl or ethyl. Preferably at least a portion of R′ is H. The organic component of the phosphonic acid (R and R″) can be aliphatic (e.g., alkyl having 2-20, preferably 6-18 carbon atoms) including an unsaturated carbon chain (e.g., an olefin), or can be an aryl or aryl-substituted moiety.
[0029] Example of monomeric phosphinic acids are compounds or mixture of compounds having the formula:
[0000]
[0000] wherein x is 0-2, y is 0-2, z is 1 and x+y+z is 3. R and R″ preferably are each independently radicals having a total of 1-30, preferably 6-18 carbons. R′ is H, a metal, such as an alkali metal, for example, sodium or potassium or lower alkyl having 1-4 carbons, such as methyl or ethyl. Preferably a portion of R′ is H. The organic component of the phosphinic acid (R, R″) can be aliphatic (e.g., alkyl having 2-20, preferably 6-18 carbon atoms) including an unsaturated carbon chain (e.g., an olefin), or can be an aryl or aryl-substituted moiety.
[0030] Examples of organo groups which may comprise R and R″ include long and short chain aliphatic hydrocarbons, aromatic hydrocarbons and substituted aliphatic hydrocarbons and substituted aromatic hydrocarbons. Examples of substituents include carboxyl such as carboxylic acid, hydroxyl, amino, imino, amido, thio, cyano, fluoro such as CF 3 (C n F 2n )CH 2 CH 2 PO 3 H 2 where n=3-15, CF 3 (CF 2 ) x O(CF 2 CF 2 ) y —CH 2 CH 2 —PO 3 H 2 where x is 0 to 7, y is 1 to 20 and x+y≦27, phosphonate, phosphinate, sulfonate, carbonate and mixed substituents.
[0031] Representative of the organophosphorus acids are as follows: amino trismethylene phosphonic acid, aminobenzylphosphonic acid, 3-amino propyl phosphonic acid, O-aminophenyl phosphonic acid, 4-methoxyphenyl phosphonic acid, aminophenylphosphonic acid, aminophosphonobutyric acid, aminopropylphosphonic acid, benzhydrylphosphonic acid, benzylphosphonic acid, butylphosphonic acid, carboxyethylphosphonic acid, diphenylphosphinic acid, dodecylphosphonic acid, ethylidenediphosphonic acid, heptadecylphosphonic acid, methylbenzylphosphonic acid, naphthylmethylphosphonic acid, octadecylphosphonic acid, octylphosphonic acid, pentylphosphonic acid, phenylphosphinic acid, phenylphosphonic acid, bis-(perfluoroheptyl)phosphinic acid, perfluorohexyl phosphonic acid, styrene phosphonic acid, dodecyl bis-1,12-phosphonic acid.
[0032] In addition to the monomeric organophosphorus acids, oligomeric or polymeric organophosphorus acids resulting from self-condensation of the respective monomeric acids may be used.
[0033] The organic acid is typically dissolved or dispersed in a diluent. Suitable diluents include alcohols such as methanol, ethanol or propanol; aliphatic hydrocarbons such as hexane, isooctane and decane, ethers, for example, tetrahydrofuran and dialkylethers such as diethylether. Diluents for fluorinated materials can include perfluorinated compounds such as perfluorinated tetrahydrofuran. Also, aqueous alkaline solutions such as sodium and potassium hydroxide can be used as the diluent.
[0034] Adjuvant materials may be present with the organic acid and the diluent (organic acid compositions). Examples include surface active agents, stabilizers, wetting agents and anti-static agents. The adjuvants if present are present in amounts of up to 30 percent by weight based on the non-volatile content of the organic acid composition.
[0035] The concentration of the organic acid in the composition is not particularly critical but is at least 0.01 millimolar, typically 0.01 to 100 millimolar, and more typically 0.1 to 50 millimolar. The organic acid composition can be prepared by mixing all of the components at the same time or by adding the components in several steps.
[0036] A wipe treated with the organic acid composition can be prepared by contacting the wipe with the composition by spraying or by immersion such as dipping. The time of treatment is not particularly critical and is usually from as short as 1 second to 60 minutes. The time of treatment can be varied to a significant extent, for example, by varying the concentration of the organic acid and by the number of wipes added to the treating composition. Typically, the amount of the organic acid composition contained on the wipe can range between 0.001 to 80, more typically, 0.001 to 30 percent by weight based on total weight of the treated wipe. The wipe can also be impregnated with an encapsulated organic acid. For example, the encapsulation material may be a soft polymer such as cellulose or gelatin that releases the organic acid when the wipe is moved across the surface being treated.
[0037] The treated wipe is stored or packaged in a container such as a pouch that is substantially impervious to the diluent so that the wipe does not dry out during handling and storage. The container or pouch may be made of a metal such as aluminum or a polyolefin selected from the group consisting of polyethylene, polypropylene, polybutene, poly(4-methylpentene-1), copolymers of propylene and ethylene, copolymers of ethylene and vinyl acetate, copolymers of ethylene and ethyl acrylate, and copolymers of ethylene and acrylic or methacrylic acid. The pouch typically has a thickness of from 0.5 to 15 mils.
[0038] The treated wipes can be packaged as numerous, individual sheets that are then impregnated or contacted with the organic acid composition for more economical dispensing. Also, the wipes can be formed as a continuous web during the manufacturing process and loaded into a dispenser, such as a canister with a closure, or a tub with closure. The closure is to seal the treated wipes from the external environment and to prevent premature volatilization of the diluent. The dispenser may be formed of a metal such as aluminum, a polymer, such as high density polyethylene, polypropylene, polycarbonate, polyethylene terephthalate (PET), polyvinyl chloride (PVC), or other rigid polymers. The continuous web of wipes could preferably be threaded through a thin opening in the top of the dispenser, most preferably, through the closure. A means of sizing the desired length or size of the wipe from the web would then be needed. A knife blade, serrated edge, or other means of cutting the web to desired size can be provided on the top of the dispenser, for non-limiting example, with the thin opening actually doubling in duty as a cutting edge. Alternatively, the continuous web of wipes could be scored, folded, segmented, or partially cut into uniform or non-uniform sizes or lengths, which would then obviate the need for a sharp cutting edge. Further, as in hand tissues, the wipes could be interleaved, so that the removal of one wipe advances the next, and so forth. The treated wipe can also be used in the form of a “marker” in which the container holding the organic acid composition contains a felt tip that is in contact with the organic acid. As the felt tip is moved across the surface to be treated, it distributes the organic acid composition to the surface.
[0039] In another embodiment, the organic acid could be stored in a spray bottle and sprayed onto the surface to be treated, for example, onto an organometallic film deposited as described below. Optionally, a wipe could then be moved across the surface to distribute the organic acid. Alternatively, after the organic acid composition is sprayed onto the surface, the diluent could simply be allowed to evaporate. For spray applications, the organic acid composition can be stored in a bottle or container made from a metal such as aluminum or the polymeric materials as described above.
[0040] The organometallic compound is preferably derived from a metal or metalloid, preferably a transition metal, selected from Group III and Groups IIIB, IVB, VB and VIB of the Periodic Table. Transition metals are preferred, such as those selected from Groups IIIB, IVB, VB and VIB of the Periodic Table. Examples are tantalum, titanium and zirconium. The organo portion of the organometallic compound is selected from those groups that are reactive with the acids (or their derivatives) of the organic acid as it is believed that the organometallic compound promotes adhesion of the organic acid to the surface being treated. Also, as will be described later, the organo group of the organometallic compound is believed to be reactive with groups on the surfaces being treated such as oxide and hydroxyl groups. Examples of suitable organo groups of the organometallic compound are alkoxide groups containing from 1 to 18, preferably 2 to 4 carbon atoms, such as ethoxide, propoxide, isopropoxide, butoxide, isobutoxide, tert-butoxide and ethylhexyloxide. Mixed groups such as alkoxide, acetyl acetonate and chloride groups can be used.
[0041] With regard to the preferred metals titanium and zirconium, the organic titanates and zirconates ranging from very reactive simple esters and polymeric forms of esters to stabilized chelated forms, these include
[0042] a. alkyl ortho esters of titanium and zirconium having the general formula M(OR) 4 , wherein M is selected from Ti and Zr and R is C 1-18 alkyl,
[0043] b. polymeric alkyl titanates and zirconates obtainable by condensation of the alkyl ortho esters of (a), i.e., partially hydrolyzed alkyl ortho esters of the general formula RO[-M(OR) 2 O—] x-1 R, wherein M and R are as above and x is a positive integer,
[0044] c. titanium chelates, derived from ortho titanic acid and polyfunctional alcohols containing one or more additional hydroxyl, keto, carboxyl or amino groups capable of donating electrons to titanium. These chelates have the general formula
[0000] Ti(O) a (OH) b (OR′) c (XY) d
[0000] wherein a=4-b-c-d; b=4-a-c-d; c=4-a-b-d; d=4-a-b-c; R′ is H, R as above or X-Y, wherein X is an electron donating group such as oxygen or nitrogen and Y is an aliphatic radical having a two or three carbon atom chain such as
i. —CH 2 CH 2 —, e.g., of ethanolamine, diethanolamine and triethanolamine,
[0000]
ii. e.g., of lactic acid,
[0000]
iii. e.g., of acetylacetone enol form, and
[0000]
iv. e.g., as in 1,3-octyleneglycol,
[0049] d. titanium acylates having the general formula Ti(OCOR) 4-n (OR) n wherein R is C 1-18 alkyl as above and n is an integer of from 1 to 3, and polymeric forms thereof,
[0050] e. mixtures thereof.
[0051] The organometallic compound is usually dissolved or dispersed in a diluent. Examples of suitable diluents are alcohols such as methanol, ethanol and propanol, aliphatic hydrocarbons, such as hexane, isooctane and decane, ethers, for example, tetrahydrofuran and dialkylethers and diethylether.
[0052] Also, adjuvant materials may be present with the organometallic compound and the diluent (organometallic compositions). Examples include stabilizers such as sterically hindered alcohols, surfactants and anti-static agents. The adjuvants if present are present in amounts of up to 30 percent by weight based on the non-volatile content of the composition.
[0053] The concentration of the organometallic compound in the composition is not particularly critical but is usually at least 0.01 millimolar, typically from 0.01 to 100 millimolar, and more typically from 0.1 to 50 millimolar.
[0054] The organometallic treating composition can be obtained by mixing all of the components at the same time or by combining the ingredients in several steps. Since the organometallic compound is reactive with moisture, care should be taken that moisture is not introduced with the diluent or adjuvant materials and that mixing is conducted in a substantially anhydrous atmosphere.
[0055] The wipes are treated with the organometallic composition generally as described above for the organic acid treatment. The content of the organometallic compound contained in the wipe is typically the amount described above for the organic acid.
[0056] The wipe treated with the organometallic compound is stored or packaged in a container such as substantially described above for the organic acid and that is substantially impervious to moisture and to the diluent associated with the organometallic compound. Examples of suitable container materials are those described above in connection with the organic acid. Polymeric materials are preferably used in combination with metallized foils. These containers are laminates comprising outer layers of the polymers mentioned above in connection with the containers for the organic acid compositions but with the core layer of a metallized film such as aluminum applied by vacuum deposition on a polyethylene terephthalate film. The thickness of the laminates is usually from about 3 to 15 mils.
[0057] The organic acid package and the organometallic package are typically provided as a kit with one container containing the organic acid composition and the second container containing the organometallic composition. The end user would then remove the treated wipes from the containers and treat the desired surface. In the embodiment in which the organic acid is in a spray bottle, the organic acid would be sprayed onto the desired surface.
[0058] Examples of suitable surfaces or substrates to be treated in accordance with the present invention are metals such as tantalum, aluminum, copper, titanium and iron, and alloys of metals such as steel and brass; metalloids such as silicon and germanium, ceramic materials such as glass and polymer materials such as polycarbonates. Preferably, the substrate is one that contains surface hydroxyls or oxide groups such as the native oxide layers associated with most metals and their alloys. Native oxide layers of metalloids such as silicon are also appropriate. Ceramic materials and polymers that inherently have reactive groups such as carboxyl or hydroxyl groups may also be used. For example, polymeric substrates may have reactive functional groups. Examples are polymers that contain hydroxyl groups such as acrylic polymers made from one or more monomers that contain hydroxyl groups. Also, composite inorganic/organic polymers such as organic polymers containing entrained silica and alumina may be used. Also, polymer surfaces may be oxidized by subjecting them to atmospheric plasma treatment in the presence of air. In the case where substrates do not have reactive groups, they may be modified. For example, a metal oxide layer may be applied to a glass or polymer substrate by sputtering, or a silicon oxide overlayer may be provided by applying a sol-gel to the substrate. Indium tin oxide is a metal oxide preferred for electrical end use applications and may be applied by sputtering. Also, metal oxides can be deposited on polymer substrates, for example, “stacked” metal oxides on polymer substrates to provide anti-reflective properties.
[0059] A particularly preferred surface is an optical or electrooptical surface such as those associated with eyewear, camera lenses and display devices such as those associated with light-emitting diodes including organic light-emitting diodes, polymer light-emitting diodes, liquid crystals and plasma screens. An anti-reflective layer may optionally be on the surface of these substrates.
[0060] The substrate or surface is typically treated by first contacting the surface of the substrate with the organometallic wipe and then with the organic acid. Treatment is typically at ambient or elevated temperature (20-200° C.) depending on the reactivity of the organometallic composition and the organic acid. The wipe(s) are moved across the surface of the substrate to transfer a film of the organometallic composition and/or the organic acid composition, as the case may be, to the surface of the substrate. The film on initial application will have a “wet look” due to the presence of the diluent. When the diluent evaporates, a film of the compound remains. The resulting films are durable in that they are not readily removed by rubbing with a cloth. The organic acid film is resistant to dirt collection and smudging and dirt and smudges are easily removed by light rubbing with a soft cloth.
[0061] Although not intending to be bound by any theory, in the case of the organophosphorus wipe, it is believed the acid group associates or bonds with the oxide or hydroxyl groups on the surface of the substrate being treated, resulting in a durable film. The organophosphorus acid self-assembles with the organo group being oriented out and away from the surface of the substrate and alters the properties of the surface. For example, a perfluorodecyl group makes the surface more hydrophobic and resistant to moisture penetration. The dodecyl group would make the surface more lubricious and resistant to dirt collection. A polar group, such as a hydroxy lower alkyl group, would make the surface more hydrophilic and possibly easier to clean.
[0062] It has been found that the organophosphorus acid wipe, particularly fluoro-substituted organophosphorus acid wipes, can also be used in the form of a repair kit to treat a surface that has a hydrophobic coating, for example, an organosilicon or organofluoro anti-smudge coating different from the organophosphorus acid. Such coatings lose their effectiveness with time. Surprisingly, treatment with the organophosphorus wipes of the present invention can revive the hydrophobicity of the surface being treated and provides a surprisingly durable coating. Also, the organophosphorus wipes and the organometallic wipes can be used in the form of a two-component repair kit in which the organometallic wipe is first used to treat a surface having a failed hydrophobic coating followed by treating with the organophosphorus wipe.
[0063] Once again, not intending to be bound by any theory, it is believed in the case of the organometallic composition, the alkoxide groups of the metal alkoxide strongly bond to the surface of the oxide and/or hydroxyl groups and to the acid groups of the organic acid at lower temperatures than when the organophosphorus acid is used alone. Also, with other organic acids, such as carboxylic and sulfonic, the intermediate organometallic layer is needed to secure the organic acid to the substrate. The bonding between the alkoxide groups and the oxide and/or hydroxyl groups and the acid groups are believed to be stronger than the bonds between the surface oxide and/or hydroxyl groups and the acid groups. This results in a more durable composite film.
EXAMPLES
[0064] The following examples are intended to illustrate the invention, and should not be construed as limiting the invention as many different embodiments can be made without departing from the spirit and scope of the invention. Therefore, the invention is not limited except as defined in the claims.
Example 1
[0065] A cotton wipe impregnated with 20 mM titanium tetra-n-butoxide in dodecane was wiped across the surface of a 4″×4″ anti-reflective film (indium tin oxide/SiO 2 stacked oxide on polycarbonate film) for 10 seconds. This resulted in a thin solvent film that evaporated leaving behind a partially hydrolyzed film of [Ti(O) x (OH) y (n-butoxy) z ] n , where x=4-y-z, y=4-x-z, z=4-y-x, and n is from 2-1000. This surface coating was then ‘activated’ by wiping (for 10 seconds) the surface with a cotton wipe impregnated with a 2 mM solution of 1H,2H,2H′-perfluorododecyl-1-phosphonic acid in ethanol. Any residue or solvent left on the surface was removed by wiping the surface with a clean, dry cloth. The contact angle of the antireflective surface increased from ˜15 degrees (untreated) to ˜118 degrees (after treatment). The surface became resistant to smudging, and dirt/smudge removal was far easier on the treated (hydrophobized) surface. The hydrophobicity of the coating could be easily regenerated (if damaged by excessive scratching, etc.) by reapplying the perfluorophosphonic acid solution.
Example 2
[0066] A 0.2 percent by weight solution of poly(hexafluoropropylene)phosphonic acid (PHFPOPA) having a weight average molecular weight of about 1582 in the perfluorinated solvent HFE-7100 from the 3M Company was prepared and used to impregnate a tissue in the form of a hand wipe. The impregnated tissue was wiped across the surface of a polycarbonate plano lens blank. The solvent was permitted to evaporate resulting in a hydrophobic coating having a water contact angle reported in Table I below. Table I also reports on the durability of the coating as determined by the decrease in water contact angle after rubbing with a microfiber cloth. The coating was considered to fail if the contact angle dropped below 95°.
Example 3
[0067] A tissue in the form of a hand wipe was impregnated with a solution of 0.25 percent by weight titanium tetra n-butoxide in petroleum distillates (100-140° C. boiling range) and wiped (for about 3 seconds) across the surface of a polycarbonate plano lens blank that has a polysiloxane anti-scratch coating (hard coat). The solvent evaporates as the hand wipe is moved across the surface of the lens and the organometallic compound is transferred to the surface. A second tissue in the form of a hand wipe was impregnated with the PHFPOPA solution of Example 2 and wiped (for about 3 seconds) across the surface of the previously applied organometallic coating. Again the solvent evaporates as the hand wipe is moved across the surface and the organophosphorus compound is transferred to the organometallic surface. The water contact angle and the durability of the coating are reported in Table I below.
Example 4
[0068] The procedure of Example 3 is repeated with the exception that the PHFPOPA solution was sprayed (finger pump sprayer) onto the organometallic coating. Excess solvent was allowed to evaporate and the residue was removed by gently rubbing with a microfiber cloth. The water contact angle and durability is reported in Table I below.
[0000]
TABLE I
Water Contact Angle and Coating Durability
Initial
Example
Contact
Contact Angle After
No.
Angle 1
10 cycles 2
20 cycles 2
30 cycles 2
50 cycles 2
2
112
108
106
107
106
3
115
114
111
102
93
4
115
114
112
108
100
1 Water contact angle determined with a Goniometer TANTEC Contact Angle Meter, Model CAM-MICRO.
2 Rubbing with a microfiber cloth with a force of 150 grams/cm 2 . One cycle is a rub back and forth.
Example 5
[0069] A Sola Teflon Easycare (anti-reflective/anti-smudge coating) on a polycarbonate ophthalmic lens was abraded with steel wool at a pressure of 150 grams/cm 2 and the decrease in water contact angle versus the number of rubs was noted. When the water contact angle dropped below 95°, the coating was no longer considered hydrophobic and the coating failed. The lens was then sprayed and then wiped with a tissue in the form of a hand wipe with a solution of 0.05 percent by weight PHFPOPA in a mixture of 89 percent by volume isooctane, 5 percent HFE-7100, 5 percent isopropanol and 1 percent of a fragrance (Repair Kit). The solvent evaporates as the solution is wiped across the surface and the PHFPOPA is transferred to the surface. The hydrophobic properties of the coating and its durability as determined with continued abrasion with steel wool is reported in Table II below.
Example 6
[0070] The procedure of Example 5 was repeated except the lens was a polycarbonate material coated with Essilor Crizal Alize anti-reflective/anti-smudge coating. The hydrophobic properties of the Repair Kit Coating and its durability are reported in Table II below.
Example 7
[0071] The procedure of Example 5 was repeated except that the lens was an INDO natural ultrafin “self-cleaning” ophthalmic lens. The hydrophobic properties of the Repair Kit Coating and its durability are reported in Table II below.
Example 8
[0072] A polycarbonate ophthalmic lens coated with a Zeiss anti-reflective layer was wiped as generally described in Example 2 with a tissue impregnated with a 0.2 percent by weight solution of PHFPOPA in 75 percent by volume HFE-7100/25 percent by volume acetone. The coated lense was aabraded as described in Example 5. When the water contact angle dropped below 95°, the abraded surface was then treated with a tissue impregnated with the PHFPPA solution as described immediately above. The solvent evaporates as the hand wipe is passed over the abraded surface and the PHFPOPA is transferred to the surface. The hydrophobic properties of repair kit coating and its durability is reported in Table II below.
[0000]
TABLE II
Water Contact Angle and Coating Durability
Initial
Apply
Exam-
Water
Contact Angle
Repair Kit.
Contact Angle
ple
Contact
after Cycles
Initial
after Cycles
No.
Angle 1
250 2
500 2
1000 2
Contact Angle
250 2
500 2
5
115
108
105
95
115
110
103
6
113
110
103
80
116
108
106
7
106
80
—
—
116
109
100
8
116
113
108
95
114
112
105
1 Water contact angle determined as in Table I.
2 Rubbing with steel wool with a force of 150 grams/cm 2 . One cycle is a rub back and forth.
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Wipes treated with organometallic compounds used in combination with organic acids in kit form, particularly organophosphorus acid, are disclosed. The kits can be used to treat various surfaces to alter the physical properties of the surfaces.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation of application Ser. No. 10/672,858, filed Sep. 25, 2003 now U.S. Pat. No. 6,845,709, which is a continuation of application Ser. No. 10/180,108, filed Jun. 27, 2002, now U.S. Pat. No. 6,651,417. The disclosure presented in this application is the same as that presented in the original application.
FIELD OF THE INVENTION
The present invention relates generally to systems and methods for forming of modules from harvested crops. Specifically, preferred embodiments of the invention relate to forming cotton modules from loose cotton.
BACKGROUND OF THE INVENTION
Over the last half century, harvesting techniques for cotton have lagged behind the typical progression of innovations in this particular farm commodity. While planting and cultivating practices have become efficient enough to successfully plant and cultivate in eight-row, ten-row, and twelve-row patterns, cotton harvesting patterns have largely remained a half-century behind in a four-row pattern. Although some six-row and eight-row cotton harvesting systems are emerging, they are not successful on a large scale. They too typically have the problems common to four-row harvesting systems, e.g., the inability to quickly and efficiently dispose of the loose harvested cotton from harvester enclosures. Cotton in loose form is difficult to store and handle efficiently. Attempts at creating commercially available methods of moving the loose cotton from the harvester enclosures directly to compacted cotton have met with limited success. This bottleneck creates a variety of problems that hinders the speed of harvest and has inadvertently stagnated further development in this particular area.
Harvesters and module builders used today have designs that are not conductive to normal progressive expansion or innovations. Typical present day harvesters remove cotton from the stalk and deposit it in loose form into an onboard enclosure commonly called a basket. This basket has a finite capacity; harvesting must be stopped periodically and the loose cotton conveyed to another machine for compaction. That other machine is commonly called a cotton module builder. The cotton module builder is transportable except during the cotton module-building phase. Normally the module builder is placed outside a cotton field in close proximity to the area being harvested. Conveyance of cotton from the basket is done either directly or by means of yet another mobile transfer receptacle. In present day use, the typical module-building machine is a rectangular box that is open-topped and floorless. Above the box is a compressing ram that traverses the length of the module incrementally compacting the loose cotton deposited from the harvester. Once a module is started it must be finished on that site; causing the harvesters contents to be delivered to one site for a finite period of time. Building modules in this fashion generally results in modules of uneven density. Such modules are more susceptible to breakage during handling and storage than modules of uniform sufficient density. In addition, top-built modules typically require a finishing compaction cycle. The finishing compaction cycle, along with the time typically required to move and then set up the module builder again, contributes to inefficiency in the harvesting and compaction process.
Other drawbacks shared by typical top-built module builders become evident in the filling cycles of these machines. In order to convey the harvester's contents to the module builder the harvester must be close enough to the module builder, or transfer receptacle, that the harvester does not lose stability in the dumping process. This close proximity to the module builder, or transfer receptacle, impedes the harvester from being equipped with a wide, eight-, ten-, or twelve-row harvest pattern. The harvester's finite enclosure also requires harvesting to be stopped until the enclosure can be emptied. This time delay, along with the time delay in transport of the cotton, and the time delays in the stationary building process presents potential loses to vulnerable cotton crops ready for harvest. The present invention addresses a majority of these problems by giving portability to the module building process offering a cotton producer several options heretofore unavailable.
Although other related art can be found, most has been met with limited success. In one instance, U.S. Pat. No. 4,553,378 to Fachini et al. ('378) discloses an auger screw which limits its ability to produce even module density. The auger mode of compaction could create an over-compaction in the center of the module potentially causing seed damage while under-compacting the module corners. In addition, the '378 patent discloses no means for separating one module from the next. Tearing the module (a means inferable from the '378 disclosure) would likely compromise the structural integrity of the module.
Further examination of this reference calls into question it's ability to construct industry accepted standard size modules because of its on board limitations. Harvesters used today must be able to follow a cotton producers typical end row turning width limitations. For this on board system to build a standard size module, the harvester would have an excessive length that would not typically be able to turn and properly realign for the next pass without loss of harvestable cotton. A typical cotton stripper is approximately 18 feet to 20 feet long. A standard module is 30 feet to 32 feet long. The two combined would be approximately 40 feet to 45 feet long. The typical end row turning space is 25 feet to thirty feet. Proper alignment of the machine would result in approximately 10 feet to 20 feet of un-harvested or poorly harvested cotton—unacceptable to most producers.
U.S. Pat. No. 4,548,131 Mobile Apparatus for the Infield Handling of Fibrous Material to Williams ('131) appears to have several limiting factors. For example, it appears to be limited to a non-continuous mode of operation. The labor in the control cabin required to operate these cycles is also undesirable. Another example is its inability to build a standard size module, i.e., 8 feet wide by 9 feet tall by 30 feet long. The dispersal of fibroid material through what appears to be a horizontally stationary duct system into the bale hopper makes no provisions for even dispersal into an elongated rectangular shape, which is the industry, standard. Very few gins have the capacity to handle cotton in any form except a standard size module. Most modern gins have invested in expensive automatic module feeders for their gin plants.
BRIEF SUMMARY OF THE INVENTION
Preferred embodiments of the present invention include a cotton module building apparatus constructed on a wheeled frame with an end-built, reciprocating, compression chamber on the front portion of the frame. The chamber receives non-compacted cotton and outputs a compacted cotton module of substantially uniform density. The compacted module is delivered to an onboard movable floor enabling the off-loading of the module at any designated site, even while harvesting continues. This apparatus for, and associated method of, cotton module construction enables the module building process to be continuously repeated while harvesting continues, substantially eliminating the down time associated with transferring loose cotton to a module builder that must remain stationary during the module building process. The module builder has the portability to be used stationary at different sites during the construction of one module or in tow behind a typical cotton harvester. Time is of the essence during a cotton harvest. Cotton producers can reap enormous benefits if they can make their harvest machinery significantly more productive.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a side view illustrating a preferred embodiment of the present invention in a pre-loading state and connected to a harvester.
FIG. 2 is a cut away side view illustrating a preferred embodiment of the present invention in a loading state and connected to a harvester.
FIG. 3 is a cut away side view illustrating a preferred embodiment of the present invention in a mid-stroke compaction state and connected to a harvester.
FIG. 4 is a cut away side view illustrating a preferred embodiment of the present invention in a fully compacted state and connected to a harvester.
FIG. 5 is a top view of a preferred embodiment of the present invention depicting boundary doors closed and the boundary doorframe approximately mid-way in its travel length.
FIG. 6 is a top view of a preferred embodiment of the present invention depicting boundary doors slightly closed for the creation of module resistance and the boundary doorframe in the forward most position.
FIG. 7 is a top view of a preferred embodiment of the present invention depicting boundary doors open and the boundary doorframe in its rearward most position.
FIG. 8 is a top view of a preferred embodiment of the present invention depicting boundary doors open and the boundary doorframe in its forward most position.
FIG. 9 is a side view of a preferred embodiment of the present invention offloading a finished module.
DETAILED DESCRIPTION
Preferred embodiments of the present invention include both an apparatus and method for modulating cotton.
FIG. 1 is a side view of an apparatus of the present invention used within a harvesting system to enhance the speed and efficiency with which cotton can be harvested. Preferred embodiments of the present invention include a holding chamber 12 . The holding chamber 12 is attached to a harvester 100 in a manner that allows harvested material to be collected and then gravity fed through a door 13 at one end of the chamber 12 . The door 13 is positioned above a compression chamber 18 that, in preferred embodiments, sits substantially centered on the pivot point of the wheeled main frame. In some embodiments, the compression chamber 18 is tapered to form a standard-sized module. Cotton is delivered to the holding chamber 12 above a compaction chamber 18 through the harvester's air delivery system 111 . Cotton is temporarily held in the holding chamber 12 until the compression stroke returns to a forward position, e.g., 30 , sufficient to allow cotton released from the holding chamber 12 to fall into the compaction chamber 18 . At this position, the door 13 at the bottom of the holding chamber 12 opens, releasing cotton into the compaction chamber 18 . This door 13 remains open until limit switches (not shown) in the compaction chamber 18 are activated. This predetermined level of fill triggers the holding chamber door 13 to close and the compression cycle to begin.
During filling of the compaction chamber 18 , cotton on the bottom of the chamber is compacted some by the weight of the cotton on top of it. This happens whether it is in this chamber 18 , or a conventional model builder, boil buggy, cotton stripper basket or any other place a substantial amount of cotton accumulates on top of other cotton. Preferred embodiments of the present invention compensate for this natural compaction by adjusting the vertical orientation of a compression surface, e.g., 14 as shown in FIG. 2
At the beginning of the cycle the compression surface 14 , which has a surface area substantially as large as the end of each module, is tilted forward to compensate for the additional loose cotton required to create a module having substantially uniform density from top to bottom. A frame 15 secures hydraulic power sources 16 that are used to create adjustable angles of the compression surface 14 . As the compression cycle proceeds, preferably as it approaches midway as shown in FIG. 3 , the compressing surface 14 moves from tilted forward to substantially perpendicular to the floor 17 of the wheeled frame. Approaching the end of the compression cycle, as shown in FIG 4 , the compression surface 14 has reached an adjustable hydraulic pressure limit switch (not shown) that presets the compaction level. The surface 14 tilts rearward in the process to create a more evenly dense module as well a properly shaped end to the module. This method of cotton module compaction is repeated continuously from module to module, preferably while the module builder is in motion behind a harvester, providing an advantage over other present day harvesting methods. This compaction cycle does not have to stop from time to time in order to transfer non-compacted cotton to a compactor/module builder, or to an intermediate transport receptacle, therefore enabling the harvest process to proceed unhindered saving harvester down time and labor as well as costs associated with ancillary equipment.
The rear part of the present embodiment is designed to receive, form, size, and offload industry-standard-sized modules in a substantially continuous manner. The continuous nature of this embodiment eliminates a substantial portion of cotton handling down time associated with presently used harvest practices. FIGS. 5 through 8 illustrate the relationships between elements of a preferred embodiment of the invention as a compacted cotton module is moved from the compaction chamber 18 and into the form chamber 19 with sequential resistance applied by the door assembly. As the compacted cotton is pressed from the compaction chamber 18 , it enters the form chamber 19 . This walled enclosure 19 , mounted to the wheeled main frame, creates a compacted cotton flow that is atop and parallel to the wheeled frame 17 . The form chamber 19 has two sides, a top and bottom, but is open on front and back and is large enough for a standard sized module to be forced through the enclosure. The rear opening where the compacted module exits is slightly larger than the front opening which joins the compaction chamber opening, i.e., the form chamber 19 is tapered, with the wider portion at the rear. Compaction and forming of the cotton are one undifferentiated process. When construction begins on a module, there is nothing in the form chamber 19 . It fills concurrently with the compression chamber 18 . After cotton has been pressed through the compaction chamber, the form chamber 19 remains full of compacted cotton. The compacted cotton is unable to fall back into the compression chamber 18 between compression strokes because it is wedged in the tapered form chamber 19 . During the remainder of this module's construction, only the compression chamber 18 has room for loose cotton fill. When the module length is approximately equal to its height, although only partially built, it has likely reached the necessary volume to become stable and static enough to be self-sustaining. The fill and compact cycle continues as follows until a module of the desired length is produced. At the end of compaction, compression surface 14 , which operates only in the compaction chamber 18 until this point, pushes the compacted module all the way through the form chamber 19 , delivering it to the movable floor 23 for off-loading. As a cotton module under construction is forced by the compression surface 14 to exit the form chamber 19 on the enlarged end, the door assembly 21 with doors 20 in the closed position FIG. 5 influences the rate of exodus. Movement of the door frame assembly along the wheeled frame 17 is controlled by an adjustable bypass value (not shown) on a set of hydraulic cylinders 22 attached to the movable doorframe 21 on each side of the wheeled frame 17 . This resistance of the door assembly, which acts as a movable wall, against the forces of the compression chamber surface determines module destiny by controlling the rate of the module lengthening process.
Forming a module of substantially uniform vertical density from a continuous supply of harvested commodity begins with the concurrent filling of both the form chamber 19 and the compression chamber 18 as described above. The door frame assembly 21 with doors 20 in the closed position moves immediately behind the form chamber 19 . As material becomes properly compacted in the form chamber 19 , it overrides the bypass valve and begins to exit this chamber 19 . The compaction forces on the closed movable doors 20 and door frame 21 cause the whole assembly to gradually be pushed rearward, as shown in FIG. 5 in comparison to FIG. 4 , as the module is formed. When the module length is approximately equal to its height although only partially built, it has reached the necessary volume to become stable and static enough to be self-sustaining. The resistance doors 20 fully open as illustrated in FIG. 7 and door frame 21 , after being activated by a limit switch (not shown), moves back to its forward most position, as shown in FIG. 8 , immediately behind the form chamber 19 . The doors 20 , by pressure regulated hydraulic cylinders, continue to create resistance on the module, as shown in the figures, to exert pressure against the sides of the module (not shown) as it extrudes from the chamber 19 . When the module is completed, e.g., when it reaches standard length, a compression stroke pushes the module through the form chamber 19 , using the compression surface 14 , as the lateral door pressure is released as illustrated in FIG. 8 . With little resistance remaining against the module, a movable floor 23 on the wheeled main frame 17 moves the newly formed module rearward enough for the doors 20 to close and the process to begin again. The rear of the wheeled main frame is lowered to offload the completed module as illustrated in FIG. 9 without having to stop the harvesting or module building process.
In some embodiments of the invention, the movable floor 23 is used (1) to help exit a finished module from the forming chamber 19 and/or (2) to help with the resistance required to maintain uniform density of a module. In some embodiments, the movable floor 23 is operable in two separate sections. One section to support a gradually moving module under construction extending from the forming chamber 19 (leading or trailing edge) to just behind the point of the doors 20 in their rearward most open position. The second section, beginning immediately behind the first and extending to the rear of the wheeled frame 17 , to support a finished module waiting for off-loading movable at ground speed. These floors 23 work in unison and independently during each cycle. Additionally, the movable floor 23 is able to run in reverse enabling the machine to serve a dual function as a module mover when not in use harvesting. Another function of the floor 23 in reverse is to pickup a detached wide row header so that the machine may be moved safely down a highway or through narrow passageways.
Preferred embodiments of the invention, because of the pivot point where the wheeled main frame 17 attaches to a stripper/harvester, will turn in substantially the same space requirements of a typical stripper/harvester. On an end turn row, and in some instances while a harvester system incorporating a preferred embodiment of the invention is beginning to strip the next row going forward the jack knifed module builder will actually be backing up so that it can realign itself while the stripper is in the forward motion.
Furthermore, preferred embodiments of the present invention are not limited to the commodity of cotton. It is readily adaptable to a variety of other commodities such as hay or silage. Commodities that embrace preferred embodiments of the present invention will gain great efficiencies of handling and harvesting from its substantially non-stop capabilities and from a finished product that is substantially the same as that created by conventional module builder.
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Module builder including holding chamber, wheeled frame towable behind a harvester; compaction chamber, compaction device, forming chamber, door assembly. The compaction chamber having compaction surface oriented between and substantially perpendicular to compaction chamber sidewalls. Compaction surface is nominally vertical and translatable through the compaction chamber at vertical and near-vertical. The compaction chamber is situated to receive material from the holding chamber. Compaction device are coupled to the compaction surface, and operative to translate it in a substantially horizontal direction through the compaction chamber at vertical and near vertical. The forming chamber is aligned with the compaction chamber trailing edge. The forming chamber door assembly includes a substantially vertical door frame at least spanning the forming chamber trailing edge, and is movable toward and away from the forming chamber along the wheeled frame. The door assembly also includes two doors mounted on the frame and movable between open and closed states.
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BACKGROUND OF THE INVENTION
[0001] The present invention relates to an extraction method for separating petroleum-containing materials into at least two fractions, and also relates to an extraction system, the solvent stripping system and an extraction fluid therefor.
[0002] An economical method to de-asphalt, fractionate and de-metalize various petroleum-containing materials is needed. The petroleum-containing materials can, for example, be waste/non-waste petroleum-containing materials such as used motor oil, virgin crude oil, vacuum tower bottoms, catalytic cracker tower bottoms, heavy oil, gas oil, tar sands/bitumin and the like.
[0003] Liquid carbon dioxide is cheap, plentiful and relatively benign in terms of toxicity and its effects on the environment when compared to other solvents. Unfortunately, carbon dioxide is a very poor solvent in the sub-critical or liquid phase, and it has little utility as an extraction fluid, especially for petroleum mixtures. Auerbach (U.S. Pat. No. 1,805,751) states that sub-critical carbon dioxide dissolves petroleum oils to form solutions of concentrations of 2 percent or less. Such extractions are highly inefficient because of the need to use and process large amounts of solvent to effect an appreciable quantity of oil.
[0004] Because sub-critical carbon dioxide is a poor solvent, recent research utilizing carbon dioxide as a solvent has been concentrated on the super-critical phase. The term super-critical as used in conjunction with a fluid refers to a highly compressed gas having a gas density approaching that of the liquid phase density. A super-critical fluid cannot be liquefied. A super-critical fluid can also be defined as a substance which is above the critical temperature and at a pressure above the critical pressure. The critical temperature is defined as the temperature above which a gas can never become a liquid regardless of the pressure. The critical pressure is defined as the pressure at which a gas can just be liquefied at the critical temperature. There are few or no intermolecular attractions (liquid bonds) in a super-critical fluid and therefore it will expand to fill the entire container. A super-critical fluid has no meniscus and the density of the fluid is constant throughout the container. This is contrasted with a true liquid which has a meniscus with the liquid phase (high density phase) at the bottom of the container and the vapor phase (low density phase) at the top of the container.
[0005] In modern chemical theory, a super-critical fluid is considered as a separate phase along with solids, liquids and gases. A phase diagram consisting of a temperature vs pressure plot shows lines dividing the solid, liquid and gaseous phases and a “triple point” where the three phases are in equilibrium. The same plot may also show the critical point where the liquid, gas and the super-critical phases are in equilibrium. Usually the boundary lines between the gas, liquid and super-critical phases are dashed because of the difficulty of measuring those boundaries. Even with this difficulty, it is well recognized that a supercritical fluid is a distinctly different phase from that of solids, liquids and gases.
[0006] Since there are few or no inter-molecular bonds or attractions in a super-critical solutions, the rule of liquid solubility (polar solvents dissolve polar solutes well and nonpolar solvents dissolve nonpolar solutes well) tends to be minimized. The general rule of solubility for super-critical solutions is solvents and solutes of like densities are soluble, which is very different from that of liquid solvent systems. To illustrate the dramatic differences in solubility characteristics between super-critical solvents and sub-critical solvents these examples are cited. Super critical water and oil are miscible. Elemental carbon is soluble in super-critical toluene. These examples indicate that it is improper to make inferences about a solution in one phase by utilizing empirical data from another phase. It is very important to consider which material is the solvent and the solute when considering systems where the solvent is of a different phase from that of the solute.
[0007] Despite claims to the contrary, carbon dioxide in the super-critical phase is actually not an exceptional solvent either. For this reason, Ohgaki et al, U.S. Pat. No. 5,138,075, starts at a somewhat sub-critical phase before heating to the super-critical phase. In addition, polar co-solvents such as water, methanol, and ethanol (<10%) have been added to super-critical carbon dioxide to increase the solubilities of potential solutes (see Dedieu et al, U.S. Pat. No. 5,329,045). Low volatile non-polar co-solvents have been added to carbon dioxide for extractions (see Heidlas et al, U.S. Pat. No. 5,626,756). Non-volatile surfactants have been used with sub and super-critical carbon dioxide in attempts to develop a commercial dry-cleaning process for clothing. The solubilities of nongaseous materials in super-critical carbon dioxide are not great enough to be commercially useful except for very specialized food, medical and scientific applications. Caffeine extractions of coffee and tea, drug and drug precursors are extracted commercially utilizing super-critical carbon dioxide.
[0008] Kriegel, U.S. Pat. No. 4,522,707, discloses the use of gases, including carbon dioxide, at super-critical conditions for processing spent oil. There are several other patents pertaining to the use of super-critical carbon dioxide in the oil industry. Harris et al., U.S. Pat. No. 5,045,220 notes that carbon dioxide easily associates with various polymers, various light hydrocarbons and water to facilitate tertiary recovery of oil from oil fields.
[0009] Older patent references often referred to super-critical fluids as liquids. Francis (U.S. Pat. No. 2,631,966), for example, presented extensive solubility data and extraction methods for virgin lubricating oils utilizing carbon dioxide and various co-solvents including propane. The various solvent systems are referred to as liquids although the data and descriptions are often presented for temperatures and pressures greater than the super-critical conditions of the solvent.
[0010] Francis describes the conditions of most of his extractions with regard to a Plait point which describes what he refers to as the critical solution point. His critical point represents the solution conditions where two liquid phases in an extraction experiment disappear when the compositions of the phases approach each other through the variation of the solvation parameters. Great care is required in the interpretation of terminology used in the old literature.
[0011] Francis describes extractions involving a (type A) co-solvent as a co-solvent which is completely miscible in liquid carbon dioxide and partially miscible in the mixture to be separated. The second (type B) extraction involves a co-solvent which is partially soluble in carbon dioxide and partially miscible in the mixture to be separated.
[0012] The patent omits another type of extraction which would have a co-solvent which is completely miscible in carbon dioxide and also completely miscible in the oil. This case is the substance of our inventive process. The Francis extractions result in fractions which he terms extract-extract, extract-raffinate, raffinate-extract and raffinate-raffinate. The co-solvent and the carbon dioxide are separated after the extractions and solvents are reformulated before reuse. Our inventive process simply flash vaporizes and recycles the solvent and co-solvent without the separation of the solvent components and without the need for reformulation of the solvent upon reuse.
[0013] Liquid propane in the sub-critical phase is used to de-asphalt petroleum materials via salvation techniques (see Mellen, U.S. Pat. No. 5,286,380, Crowley, U.S. Pat. No. 4,169,044, Wezel, U.S. Pat. No. 4,797,198, and Vu, U.S. Pat. No. 3,773,658). Propane easily solvates oils which are removed from a mixture then heated to the super-critical phase to lower the solubility and to recover the oils. Small quantities of carbon dioxide, hydrogen sulfide, etc. have been added to modify or lower the solvent properties of propane. (see, for example, Yoon et al, U.S. Pat. No. 5,587,085, and Heidlas et al, U.S. Pat. No. 5,616,352). It should be noted that propane as an extraction fluid is too good of a solvent to efficiently fractionate petroleum mixtures. Lipid oils and cholesterol from various sources have been extracted using pure propane and propane with small quantities of co-solvents, such as carbon dioxide.
[0014] Van Dijck (U.S. Pat. No. 2,281,865) utilized extraction separations by commingling a pure solvent with a petroleum mixture. Various low molecular weight, high volatile solvents including pure propane and pure carbon dioxide were utilized. After an equilibrium solution was reached the pressure was released step-wise resulting in the settling of a high molecular weight fraction layer. The separated layer was removed before the pressure was lowered to the next step. The step-wise lowering of the pressure and the resultant requirement for the formation of a new equilibrium restricted the separation to a batch process method. The temperatures of these extractions were usually below but near the critical temperatures of the solvent.
[0015] Webb (U.S. Pat. No. 2,246,227) diluted lubricating oils with propane and then treating the resulting solutions with methane to produce separations of oils into fractions of different densities.
[0016] Lantz (U.S. Pat. No. 2,188,051) utilized low molecular weight hydrocarbon solvents (7 carbons or less) to solvate the oil under consideration. The solvent properties of the light hydrocarbon are then modified with the addition of carbon dioxide to form petroleum fractions of lower and higher viscosities. He further states that the extractions work best utilizing branched chain hydrocarbon solvents such as isobutane and isopentane solvents and in solvent concentrations of 75% or more. The recovery of the solvent components requires separate systems to recover the carbon dioxide and the hydrocarbon solvent.
[0017] It is an object of the present invention to provide an improved and economical method to de-metalize, de-asphalt and fractionate petroleum-containing materials such as used motor oil or virgin light crude oil, heavy crude oils and tar sands/bitumen using specific sub-critical solvent/co-solvent mixtures.
[0018] It is another object of the present invention to clean diesel fuels, fuel oils, aviation gasoline and other fuels.
[0019] It is a further object of the present invention to clean and separate oil from earthen materials after oil spills as well as to clean oil from plastics prior to plastic recycling.
[0020] It is also an object of the invention to separate the constituents of extremely viscous materials such as cracker tower bottoms and gas oils.
[0021] It is a further object of the present invention to provide an extraction system to carry out such a method.
[0022] It is another object of this invention to efficiently separate the solvent/co-solvent mixture from the extract products in a simple single step process while maintaining a constant solvent to co-solvent ratio.
[0023] It is also an object of this invention to utilize much of the heat of vaporization obtained from the solvent recovery system to vaporize the solvent in the solvent stripping system.
[0024] These and other objects and advantages of the present invention will be described in detail subsequently in conjunction with the accompanying schematic drawing, which is a flow diagram explaining the inventive method in conjunction with one exemplary embodiment of the inventive extraction system.
SUMMARY OF THE INVENTION
[0025] The method of the present invention is characterized primarily by introducing into an extraction vessel, such as an extraction column, petroleum-containing material as well as a solvent mixture comprising 50%-99% by volume sub-critical carbon dioxide and 1%-50%, especially 5%-40%, by volume of at least one high volatile co-solvent (with an ambient boiling point of 0° C. or lower), which can be propane, ethane, butane, propylene, 2 methylpropane, 2,2 dimethylpropane, propadiene, dimethylether, chlorodifluoromethane, difluoromethane, methylfluoride and others; a fraction containing solvent mixture and solvated petroleum-containing material, and a dense fraction of the petroleum-containing material, as well as solvent mixture, are removed from the column upon the formation of a density gradient within the column.
[0026] Thus, it can be seen that solvent mixtures comprising sub-critical liquid carbon dioxide and high volatile co-solvents are used to solvate one or more petroleum products that are desired to be removed from petroleum-containing material. For example, asphalts, partial oxidation products, water, wear metals and other contaminants are insoluble in the solvent mixtures and are separated from the desired oil product in the extraction system. The highly volatile, low-flammable solvents are easily stripped from the extracted materials and can be reused without reformulation. The mild temperature conditions of the fractionation eliminate any pyrolysis product formation.
[0027] The low-flammable extraction fluids are used to solvate the desired component or components from the petroleum containing material in a separation or extraction column that is thermostated at, for example, 0° C. The extracted oil/solvent mixture is removed from the column and passes a pressure reducing regulator, thus maintaining sub-critical conditions, into a degassing boiler that is thermostated at, for example, 80° C. It is to be understood that other suitable means of degassing or separating the extraction fluid or mixture can be utilized. The high volatile solvent mixture easily distills at constant pressure from the boiler to a condenser at, for example, 0° C. for immediate reuse. The extracted oil remains in the degassing boiler which has a temperature low enough to prevent any pyrolysis products. The differential between the condenser temperature and the boiler temperature is low enough to allow for a simple refrigeration system to pump the heat from the cold solvent condenser to the hot degassing boiler. The solvent mixture is then the working fluid for the refrigeration system. A well-insulated extraction system consumes very little energy during operation. The solvent/co-solvent extraction fluids tend to lower the viscosities of petroleum mixtures so that high viscosity or dense petroleum feedstocks can be separated with ease. The high volatility of carbon dioxide based solvents as compared to higher molecular weight based solvents offers an advantage in degassing the recovered oils.
[0028] The co-solvent or co-solvents that are mixed with the liquid carbon dioxide to produce the solvent mixture will greatly modify the solubility of materials in the mixture. For example, with the present invention the solubilities of petroleum oils can be increased from about 0.05% in pure carbon dioxide to about 10% in a 25% propane/75% carbon dioxide mixture. The proper propane/carbon dioxide ratio of the extraction fluid is important for a successful extraction. For example, if the ratio is too small, the extraction rate is slow, although with good component differentiation. Conversely, if the ratio is too large, the extraction rate is more rapid, but with poor component differentiation. The extraction temperature is also important in order to obtain efficient extractions. Presently, the most effective extraction temperature appears to be at about 0° C. for petroleum products. Lower temperatures result in slow extractions but with good component differentiation, while higher temperatures result in higher extraction rates but with poor component differentiation.
[0029] In general, where the solvent mixture contains 25% by volume or less propane, the solubilities of low molecular weight hydrocarbon compounds are greater than high molecular weight hydrocarbons. The solubilities of light aromatic hydrocarbons are slightly greater than light aliphatic hydrocarbons. Wear metals or partial oxidation products in used motor oils remain in the insoluble or dense black, tarry, asphalt-like fraction.
[0030] The high volatile co-solvents are essentially miscible in the petroleum-containing material in all concentrations and have a vapor pressure of one atmosphere or greater at 0° C. The petroleum-containing materials must have a vapor pressure of less than 0.1 atmosphere at 0° C. and a specific gravity of 0.8 or greater.
[0031] With the present invention, it is also possible to obtain more than two fractions from a feed stock where the feed stock contains three or more petroleum components. By way of example, the low density solvated fraction extracted from the extraction column utilizing a first solvent mixture could contain two or more components that could than be further separated utilizing a second column and second solvent mixture. Similarly, the dense fraction of the petroleum-containing material withdrawn from the bottom portion of the extraction column could contain two or more components, which could then also be separated further utilizing a different solvent mixture. The petroleum-containing material could be processed either in a batch system, or in a continuous flow system utilizing two or more extraction columns. Separate degassing systems would of course be needed to recover the different solvents involved and to prevent cross contamination of the various solvents.
[0032] Further specific features of the present invention will be described in detail subsequently.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0033] While the various features of this invention are hereinafter illustrated and described as providing an extraction system for re-refining used oil, such as motor oil, this is done by way of example only and it is to be understood that the various features of this invention can be utilized singly or in various combinations thereof to provide an extraction system to separate any number of petroleum-containing materials into at least two fractions.
[0034] Therefore, this invention is not to be limited to only the embodiment illustrated in the drawing, because the drawing is merely utilized to illustrate one of the wide variety of usages of this invention.
[0035] Referring now to the drawing in detail, FIG. 1 illustrates an exemplary embodiment of the extraction system of this invention, which is indicated generally by the reference numeral 20 .
[0036] Used motor oil, or other petroleum-containing material and solvent mixture, the composition ratio of which is contingent upon the particular petroleum feedstock, are introduced via the lines 21 and 21 ′, 32 respectively through a mixing orifice 23 into the top portion an extraction tower or column 22 , which is held at an appropriate thermostated temperature, for example 0° C. The pumping rates of both the used oil and the solvent mixture are carefully adjusted to match extracted oil rate to prevent column flooding and/or inefficient extraction. The petroleum-containing material and the solvent mixture can be introduced into the column 22 in any convenient manner, including pumping and spraying. The used motor oil is then allowed to percolate down through the packing material (which is flooded with the less dense solvent mixture) of the column; such packing material may comprise, for example, metal shot, glass beads, trays or other packing materials, depending upon the petroleum feedstock that is being separated. Packing material is generally needed for efficient solvation and to break up and reduce solvent/oil suspensions. It should be noted that the viscosity of a highly viscous feedstock can be lowered by making a saturated solution/suspension of the feedstock, which can then be easily introduced into the extraction column 22 at the appropriate extraction temperature.
[0037] To prevent agitation and to facilitate the settling of the most dense factions of the used motor oil, such as tarry oxidation products, water and wear metals, a series of closely spaced baffles are placed in the bottom portion of the extraction column 22 below the oil solution exit line 24 . The dense fractions of the used motor oil that have settled to the bottom of the extraction column 22 are removed, for example, via the line 25 .
[0038] Solvent mixture and the solvated oil are removed from the bottom portion of the extraction column 22 and are conveyed, for example via the large volume line 24 , to a vertical settling chamber 26 , which may be open or packed, to remove any remaining entrained dense fraction. The dense fraction, obtained from chamber 26 , simply flows down and back through line 24 to line 25 . The less dense solvent oil solution is removed from the top portion of chamber 26 , for example via line 27 , which may or may not contain a pressure reducing regulator 27 ′, to the first solvent and petroleum recovery portion 28 . The recovery process involves first introducing the solvent mixture and solvated fraction into the degassing boiler 29 , which is held at a temperature of, for example, 80° C. The highly volatile solvent mixture simply distills out of the extracted oil (flash volatilization) and passes, for example via a large volume tube 30 , into the condensing tank 31 , which is held at a temperature of about 0° C. From the condensing tank 31 , the solvent mixture can be conveyed back via the line 32 to the extraction column 22 for immediate reuse as the extraction fluid. The extracted oils remain at the bottom of the degassing boiler 29 and can be removed as re-refined oil via the line 33 . Appropriate valves can be provided in the various lines.
[0039] The dense fraction that is removed from the bottom of the extraction column 22 , and which also contains some solvent mixture, is conveyed via the line 25 to the second solvent and petroleum or waste recovery portion 35 , for example via the interposition of a heater 36 . Solvent recovered in the recovery portion 35 , for example by flash vaporization, is also returned to the extraction column 22 for immediate reuse, for example via the line 37 or via the condensing tank 31 . Residual solvent remaining in the extracted oil fraction coming from the degassing boiler 29 can also be recovered in a recovery portion, similar to the recovery portion 28 or 35 , as indicated by the dashed line 38 . The high density fraction of the petroleum-containing material, such as asphalt, as well as metal, partial oxidation products, etc., is removed from the second solvent and petroleum or waste portion 35 via the line 39 . Residual solvent remaining in the asphalt can be recovered in a further recovery portion 40 . It should be noted that the composition of the extraction fluid does not change with use, and therefore does not need to be replaced or reformulated very often.
[0040] Although the present invention has been described as introducing both the petroleum-containing material and the solvent mixture into a top portion of the extraction column, it is to be understood that a countercurrent arrangement would also be possible. In such a case, the solvent mixture would be introduced into a lower portion of the column; removal of solvated material could be from the top of the column.
[0041] As indicated above, the extraction fluid can be used to separate used crankcase oil into two fractions. The first fraction consists of an amber oil with a yield of about 90%, depending upon the source of the used oil. The heavy second fraction contains asphalts, partial oxidation products, wear metals and water in a yield of about 10%. The solvent mixture effectively releases metal particles from the motor oil additive/wear metal suspensions that are found in used motor oils. The low viscosity of the oil/solvent mixtures allows for the settling of the asphalts, partial oxidation products, wear metals and water in a column, such as the extraction column 22 . The solvent flow rate within the column is about 5 cm /min to 40 cm/min depending upon the degree of separation required.
[0042] As discussed previously, where the feedstock contains three or more petroleum components, more than two fractions can be obtained. This can be accomplished in a batch-type process, or could expediently be accomplished sequentially, and hence in a continuous flow system. Thus, for example, if the extracted oils or other material removed from the bottom of the degassing boiler 29 contain two or more components, such extracted oils could be processed in the further system 41 that is indicated by dashed lines. Such a system would include at least one further extraction column, to each of which different solvent mixtures would be added depending upon the components of the extracted oils, from which the various components could then be extracted sequentially. Similarly, if the asphalt or other high density fraction of the petroleum-containing material that is recovered in the portion 35 contains two or more components, such high density fraction could be processed in a further system 42 , again as indicated by dashed lines
[0043] Further applications for the extraction fluid include, for example, the separation of catalytic cracker bottoms into two principal fractions. The first fraction is a yellow light cycle oil (about 60% yield) which slowly oxidizes and darkens with time and air. Some fractionation occurs during the progression of a batch-type extraction. Heavier waxy fractions are obtained as the extraction progresses. Although the light cycle oil contains sulfur compounds, it is compatible for blending with diesel fuel. The second fraction is a heavy brown sticky tar-like material that softens at about 80° C. This material may be suitable for carbon black production or for compounding with road asphalt.
[0044] In addition, vacuum tower bottoms can be separated, resulting in an oil and a crumbly black solid material. Gas oil, which is a distillate from vacuum tower distillations, can also be separated into a heavy clear amber oil and a heavy brown sticky tar-like material (<2%), as described above. The amber oil can then be cracked to various fuels with less catalytic contamination. In addition, a mixture of aromatic and aliphatic hydrocarbons can be partially separated into two fractions. One fraction is enriched in aromatic hydrocarbons, and the other is enriched in aliphatic hydrocarbons. A crude oil can be separated into a light combustible fuel, a heavy combustible fuel, an amber oil and a crumbly asphalt residue. The yields of these components are variable depending upon the crude oil source.
[0045] Paraffin wax can be precipitated from an octane-paraffin wax solution. Asphalt can be precipitated from an octane-asphalt solution. Residual oil and bitumen can be separated from road asphalt and tar sand. In addition, asphalt and oil can be separated from light hydrocarbons such as hexane, gasoline, kerosene, toluene, benzene etc. Hydrocarbons can be extracted or separated from organic and aqueous phases. For example, xylenes can be separated from ethylene glycol or glycol based solvents. Oils can be separated from aqueous phases. Contaminants such as water, dirt, dust, metals and asphalt can be removed from contaminated aviation fuel. Some cutting oils can be regenerated when the metal contaminants are removed.
EXAMPLE 1
[0046] An 80% carbon dioxide/20% propane mixture was used to re-refine used motor oil. Depending upon the used oil that was processed, the amber base oil fraction obtained was in the 85%-90% yield relative to the original used motor oil, and an asphaltic fraction was obtained in a range of 10%-15% yield. The metal contaminants in the recovered base oil motor oil were generally reduced to the 0-3 ppm range.
EXAMPLE 2
[0047] Cracker tower bottoms can be extracted with a 60% carbon dioxide/40% propane mixture, whereby a yellow light cycle oil in yields of up to 60% can be obtained. The remaining 40% has an improved carbon-to-hydrogen ratio which makes it more suitable for the production of carbon black or as an additive to road asphalt.
EXAMPLE 3
[0048] Used motor oil was extracted using a 60% carbon dioxide/40% propane mixture. A blackish oil product was obtained at a yield of >90%, and was free of water and metal contaminants. This product was suitable for use as fuel oil or as cracker feedstock.
EXAMPLE 4
[0049] A light hydrocarbon (hexane, gasoline, toluene, kerosene etc.)/oil mixture can be extracted using a 95% sub-critical carbon dioxide/5% propane mixture. Three fractions comprising C5 to C10, C10 to C17, and heavier oils are obtained.
EXAMPLE 5
[0050] Shredded plastic bottles contaminated with oil were extracted with a 60% carbon dioxide/40% propane mixture. The oil was removed, leaving behind clean plastic material that can be recycled.
EXAMPLE 6
[0051] Contaminated aviation fuel can be extracted using a 80% carbon dioxide/20% propane mixture. A clean aviation fuel of up to 100% yield can be obtained, with the contaminants such as water, metal, dirt and lint being left as residue.
[0052] The present invention is, of course, in no way restricted to the specific disclosure of the specification and drawing, but also encompasses any modifications within the scope of the appended claims.
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A method of separating a petroleum-containing material into at least two fractions, an extraction system, and an extraction fluid therefor are provided. Petroleum-containing material as well as a solvent mixture comprising 50%-99% by volume sub-critical carbon dioxide and 1%-50% by volume of at least one co-solvent are introduced into an extraction column. The co-solvent can be propane, ethane, butane, propylene 2 methylpropane, 2,2 dimethylpropane, propadiene, dimethylether, chlorodifluoromethane, difluoromethane and methylfluoride. A fraction containing solvent mixture and solvated petroleum-containing material is removed from the top portion of the extraction column, while a dense fraction of the petroleum-containing material, as well as solvent mixture, is withdrawn from the bottom portion of the extraction column. Solvent mixture is recovered from the solvated petroleum-containing material.
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[0001] The present invention relates to a process for the production of polylactide (PLA). Particularly, the present invention relates to an improved process where the goal is to recover a maximum of useful matters in order to recycle without loss and so significantly improving the global yield of the production process of PLA when starting from lactic acid.
BACKGROUND
[0002] Mainly two types of process have been described for the production of PLA; the first one consists in a direct polycondensation of lactic acid, as described for instance in JP patent 733861; such type of process is limited by the use of a solvent and the difficulty of removing water out of the reaction medium.
[0003] It is well known that in a second type of usual process for producing PLA starting from lactic acid, a significant loss of products, including lactic acid, lactide, oligomers of lactic acid and similar, occurs at each step of the global polymerization process; such steps may be summarized as follows: (i) oligomerization of lactic acids into oligomers, (ii) cyclization of the oligomers into lactide species, (iii) purification of lactide to obtain a suitable grade to start the last step which is the polymerization by ring opening of the purified lactide. Of course after this last step a devolatilization shall take place to recover the non-converted lactide.
[0004] Depending of the various processes for the production of PLA, it may be said that a lot of matters are lost all along the achievement of the process, so decreasing considerably the overall yield of said process. Indeed, if we take as a reference, a theoretical process without any recycling, the overall yield is as low as about 50% (molar).
[0005] It was therefore envisioned in the past to control certain partial recycling of streams issued from the step of evaporation of water from the starting lactic acid aqueous solution, from the step of oligomerization and from the step of the cyclization reaction; with such recycling operations, the overall yield has reached values as high as 75% (molar); however, even with those efforts which have been made and described to recover and finally recycle such type of lost product, this is not yet satisfactory to conduct an industrial process.
[0006] Therefore, there is a need for a process which enables not only to drastically reduce such loss of products, but mainly to incorporate in a global process the implementation of the recovery of the lost products and a process to convert such products to the starting monomer or its derivatives.
[0007] Therefore, the object of the present invention is to provide a process for the production of PLA wherein the recovery of the oligomers of lactic acid, lactide, and catalytic residues as well are implemented in order to treat and convert them into the starting monomer or its derivatives.
[0008] Another object is to recover the residues at each step of the process.
[0009] A further object is to treat the residues of lactic acid oligomers.
[0010] Another object is to implement the recovery and the recycle of the streams of lactic acid and water.
[0011] Another object is to provide a trans-esterification process to convert the oligomers residues with an alcohol.
[0012] Finally the process of the invention should also provide for treating the formed lactate compounds by hydrolysis in order to recover the alcohol and the lactic acid or its derivatives.
[0013] At least one of these objectives is met by the process of the invention.
DETAILED DESCRIPTION
[0014] The process of the present invention is also described in view of the accompanying drawings where FIG. 1 is representing the global flow sheet of a process for the production of PLA with the recovery steps and conversion steps to the starting monomer.
DESCRIPTION OF THE GLOBAL PROCESS
[0015] The present invention provides an integrated process for the production of polylactide (PLA) comprising the steps of:
(1) Water evaporation from the lactic acid aqueous solution starting stream; (2) Oligomerization of lactic acid and recycle of reaction water and unconverted lactic acid; (3) Cyclization of the lactic acid oligomers and production of crude lactide and recycle of unreacted monomers, catalytic residues and heavy products; (4) Purification of the crude lactide and recycle of lactic acid, water, heavy components, catalytic residues and impurities; (5) Ring opening polymerization of the purified lactide and production of PLA; (6) Purification of the PLA by devolatilization and recycle of non-reacted lactide;
wherein
recycle of step (2) comprises water, which is purged, and lactic acid which is recycled to reactor ( 20 ); recycle of step (3) is sent to trans-esterification reactor ( 80 ); recycle of step (4) comprising (i) the light components, is sent to reactor ( 20 ) the other part to the hydrolysis reactor ( 90 ), and (ii) the heavy components stream is sent to trans-esterification reactor ( 80 ); recycle of step (6) is sent partially to step (4) and the rest is sent to trans-esterification reactor ( 80 ).
[0026] The first step of the process to produce PLA consists in the removal of water from the starting aqueous solution of lactic acid (from 50 to 100% concentration) and the second step consists in the oligomerization of the lactic acid monomers into oligomers of low viscosity and molecular weight, generally comprised between 400 and 5,000 Dalton, in presence or not of a catalyst like for example a tin based catalyst. Typical temperature and pressure range for these two steps are respectively 100° C. to 200° C. and 5 mbara to 500 mbara. The molecular weight was measured by chromatography by gel permeation compared to standard polystyrene in chloroform at 30° C.
[0027] From these first and second steps, the process of the invention provides for the recovery of water, non-reacted lactic acid, oligomers of lactic acid.
[0028] The Applicant has noted that the residues of water and lactic acid are relatively pure, and therefore may be directly recycled to the evaporation step or the oligomerization step.
[0029] The Applicant has found that such a recycling of lactic acid could represent up to 5-15% by weight of the incoming lactic acid stream.
[0030] The oligomers coming from the step of oligomerization are then sent to the cyclization step which consists of treating the oligomers in a cyclization reactor, in the presence of a usual catalyst for such reaction like a tin based catalyst. From this third step, and besides the obtained crude lactide stream which will be sent to the purification, it is necessary to recover the unreacted oligomers, the non volatile impurities, the high boiling point lactic acid oligomers, the low molecular weight polylactic acid, having a molecular weight comprised between 2,000 and 8,000 Dalton, as well as the heavy residues and the catalytic residues which all form the cyclization residues. Typical temperature and pressure range for this step are respectively 200° C. to 320° C. and 5 mbara to 80 mbara.
[0031] These cyclization residues are sent back to the oligomerization step. However it is important to note that in order to avoid dramatic accumulation of catalytic residues in the system as well as degradation by-products, a purge is absolutely needed, which also contribute to the elimination of impurities giving rise to unwanted color. The products of the purge are then sent to the trans-esterification reactor ( 80 ).
[0032] During the fourth step, which is the purification of the crude lactide stream which may comprise different types of purification units like distillation means, crystallization means and analogs, it is recovered a light components stream containing lactic acid and water which is divided into two sub-streams, the first, representing from 10 to 100% by weight of the light components stream, is sent to the hydrolysis reactor ( 90 ) while the second, representing from 0 to 90% by weight of the light components stream, is recycled to reactor ( 20 ), while a bottom stream, containing heavy oligomers, lactide and impurities constituting stream will be recycled to the trans-esterification reactor ( 80 ).
[0033] The purified lactide is finally sent to the step of polymerization by ring opening to form PLA, having a molecular weight comprised between 10,000 and 200,000 Dalton.
[0034] This polymerization step is followed by a devolatilization step to purify the obtained PLA and to recover unreacted monomers and diluents as well as impurities.
[0035] The Applicants have now found that by operating the improved process of the invention, which comprises the steps of the water evaporation, oligomerization, crude lactide production, purification of the crude lactide, polymerization of the purified lactide by ring opening (ROP), devolatilization and the recovery of PLA, the improvement consists in:
(i) recovery water and lactic acid in steps evaporation, oligomerization, cyclization and purification, and sent them back to step of evaporation and/or oligomerization, (ii) recovery of oligomers of lactic acid, lactide, catalytic residues of steps cyclization, purification, and devolatilization and sent them back to a trans-esterification reactor, where a trans-esterification reaction shall take place, and finally (iii) send the so formed alkyl lactate to a hydrolysis step to recover the starting monomer.
[0039] According to the process of the present invention, the trans-esterification reaction may be operated in accordance with known processes and under usual conditions; such a reaction may be achieved in one or more than one reactors at a temperature comprised between 80 and 200° C. and at a pressure comprised between the atmospheric pressure and 10-50 bara and in the presence of a catalyst.
[0040] According to one embodiment of the process of the present invention, the recycle stream from cyclization (noted step (3)) and the heavy components recycled from lactide purification (noted step (4)) and the part of stream coming from devolatilization (noted step (6)) are collected and sent to the trans-esterification reactor ( 80 ) where the trans-esterification reaction is conducted in one or more than one continuous stirred reactors working at a temperature ranging between 80 and 200° C., preferably between 100 and 180° C. and at pressure ranging between 1 and 20 bara, preferably between 2 and 15 bara, and finally the recovery of a stream comprising alkyl lactate which is sent to the hydrolysis reactor ( 90 ).
[0041] Generally the catalyst is at least partially supplied with the flow recovered from the cyclization step coming from the production of crude lactide stream.
[0042] With the trans-esterification reaction an alkyl lactate is formed and recovered which is further sent to a hydrolysis step to finally recover the starting monomer.
[0043] Before being sent to the hydrolysis reaction, the crude alkyl lactate exiting the reactor ( 80 ) is first purified in order to separate the lactate molecules from the heavier molecules. With this purification step, it is generally expected to recover substantially 80 to 100% of the lactate molecules, based on the fed lactate molecules. Usually, to achieve such a separation, the mixture coming out of the trans-esterification reactor ( 80 ) is first sent to a distillation step operated under pressure of 0.01 to 4 bara preferably between 0.1 to 1 bara and at a temperature comprised between 40 to 180° C., preferably between 60 to 150° C., said distillation step comprising one or more than one distillation columns or equivalent apparatus, where it is recovered at one side, the light components like lactate molecules which are then sent to the hydrolysis and on the other side the heavy components such as the catalytic residues, oligomers and the unreacted products, which are partially recycled to reactor ( 80 ) for trans-esterification and the rest is purged and optionally treated for example by filtration or decantation to separate the catalytic residues from the oligomers. These catalytic residues can be sent back to trans-esterification and/or oligomerization and/or cyclization reactors as such or with an additional treatment (e.g. drying).
[0044] The hydrolysis reactor (noted 90 ) is receiving, after distillation, the stream from the trans-esterification reactor as well as the part of light components coming from the purification of lactide and which is directly sent to the hydrolysis reactor. The hydrolysis reactor is then operated in accordance with the usual process to achieve such reaction and in accordance with usual conditions.
[0045] The hydrolysis reaction may be summerized as follows:
[0000] Alkyle lactate+water→lactic acid+alcohol.
[0046] According to one embodiment of the present invention, this type of reaction is achieved either in batch or continuously, and the reactor for such reaction may be realized generally in a reactive distillation column, a plug flow reactor or a continuous stirred reactor system operated at a temperature comprised between 70 and 180° C., preferably 90 to 150° C. and at a pressure comprised from 0.01 and 10 bara, preferably between atmospheric pressure and 3 bara.
[0047] The alcohol, which is most often an aliphatic alcohol having from 1 to 12 carbon atoms might be withdrawn from the reaction medium in order to increase reaction efficiency. The hydrolysis reaction may be conducted in the presence of a catalyst, which may be lactic acid itself.
[0048] The finally recovered lactic acid may be further concentrated and then recycled to the oligomerization reaction, or to the upstage lactic acid production step.
[0049] The process of the invention has the unexpected advantage that it can recover all the residues which are mentioned like water, lactic acid oligomers and lactide, that cannot be done in the previous processes, and therefore, the process of the invention enables to reach very weak amount of lost products.
[0050] The overall process for producing PLA and taking into account the steps of the present invention to drastically reduce the loss of products while recovering a maximum and recycling the products like water, lactic acid, oligomers, catalytic residues at the different steps may be described in view of FIG. 1 which represent a flow sheet of the process.
[0051] An aqueous solution of lactic acid is subjected to water elimination through evaporation. The eliminated water recovered from reactor ( 20 ) which contains some lactic acid is then recycled to reactor ( 20 ), while the main flow coming out from reactor ( 20 ) is sent to the oligomerization reaction in reactor ( 30 ). During said oligomerization reaction, some water, lactic acid, which has not oligomerized are withdrawn from reactor ( 30 ) and after separation of the water, which is simply purged, the remaining lactic acid is recycled to reactor ( 20 ).
[0052] The main flow coming out from reactor ( 30 ) is sent to the cyclization reactor ( 40 ) for the production of a crude lactide stream. From reactor ( 40 ), a flow is withdrawn containing the unreacted oligomers, catalytic residues and heavier products, said flow being sent to the trans-esterification reactor ( 80 ).
[0053] The crude lactide stream resulting from cyclization is then sent to purification of lactide and which is represented by reactors ( 50 ), comprising any well known apparatus used for such purification and comprising at least distillation and/or melt crystallization means.
[0054] From purification step, represented by reactor ( 50 ), the light components lactic acid and water are recovered and recycled to reactor ( 20 ), while part of it, which may be up to 100%, is sent to the hydrolysis reactor ( 90 ) where lactic acid can act as catalyst of the hydrolysis reaction. Depending on lactic acid concentration in this stream and hydrolysis process efficiency, the minimum content of the light components stream to be sent to the hydrolysis reactor evolves between a few to several tens of percents. On the other hand the heavier components, the impurities and catalytic residues withdrawn from purification step, represented by ( 50 ), are recovered and recycled to the trans-esterification reactor ( 80 ).
[0055] The purified lactide is then sent to ring opening polymerization in reactor ( 60 ) and the obtained PLA is purified in a devolatilization reactor ( 70 ).
[0056] From the devolatilization reactor ( 70 ) it is recovered and recycled the non reacted lactide which is withdrawn and recycled partially to lactide purification or directly to the trans-esterification unit ( 80 ).
[0057] The process of the invention is further described by the following examples which are in no way limitative of the scope of the invention.
EXAMPLES
Example 1
[0058] We started with 6,000 Kg of an 88% aqueous solution of lactic acid.
[0059] This solution was subjected to water elimination by heating at a temperature of 100° C. and under reduced pressure of 250 mbara.
[0060] Water recovered was purged and the lactic acid recovered was recycled to reactor ( 20 ).
[0061] The concentrated lactic acid (100%) is sent to reactor ( 30 ) for oligomerization, which is operated at temperature of 160° C. and at a reduced pressure of 250 and down to 80 mbara, to produce oligomers of lactic acid having a molecular weight of about 950 Dalton (comprised between 900 and 1,000 Dalton.).
[0062] From reactor ( 30 ) water is withdrawn and purged, while unreacted lactic acid is recovered and recycled to reactor ( 20 ).
[0063] The oligomers formed in reactor ( 30 ) were then sent to the cyclization step in reactor ( 40 ).
[0064] The cyclization of the oligomers of lactic acid was achieved in the presence of Sn octanoate as catalyst, at a temperature of 250° C. and pressure of 10 mbara and enabled to produce a crude lactide stream.
[0065] From reactor ( 40 ), the unreacted oligomers, the catalytic residues as well as the heavier components were withdrawn and the withdrawn flow was sent to the trans-esterification reactor ( 80 ).
[0066] The crude lactide stream coming out from reactor ( 40 ) was sent to the purification step of the crude lactide. Said purification comprises, in the present example, melt crystallization means ( 50 ), from which the heavy components withdrawn from melt-crystallization means ( 50 ) were recovered and sent to the trans-esterification reactor ( 80 ).
[0067] The obtained lactide was then subjected to ring opening polymerization in reactor ( 60 ) at a temperature of 185° C. during 30 minutes in the presence of Sn octanoate and the obtained PLA is purified in a devolatilization reactor ( 70 ) from which the non-reacted lactide was removed and recycled to lactide purification. In case of presence of catalytic or other impurities, devolatilization stream can be sent to trans-esterification reactor ( 80 ).
[0068] We finally recovered PLA with an overall molar yield of 96%.
Example 2
[0069] By way of comparison a process has been conducted with the recycling as described in the prior art, meaning at the evaporation step, at the oligomerization and cyclization steps. The overall molar yield obtained in said comparative process was of 78%.
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The present invention relates to an improved process for producing polylactide where the goal is to recover a maximum of useful matters in order to recycle without loss and so significantly improving the global yield of the production process of polylactide when starting from lactic acid.
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TECHNICAL FIELD
[0001] The present application relates to an amplification method of probed-templates through binding of telomeric C-ssDNA (ABTC), and a kit for detecting alternative lengthening of telomeres (ALTs) by means of the present method.
BACKGROUND
[0002] Telomere is a structure formed of DNA repeat sequence (TTAGGG) n and some binding proteins at both ends of the eukaryotic chromosome. The telomere has the function of protecting the end of the chromosome from deterioration or from fusion, and it plays an important role in chromosomal location, replication, protection and in control of cell growth and survival, and is closely correlated with the cells apoptosis, transformation and immortalization. The telomere replication is accomplished by telomerase, a special reverse transcriptase, rather than by the typical DNA polymerase. In somatic cells of a normal person, as the expression of the telomerase is shut down, the telomere at the end of the chromosome is gradually shortened with cell division until the cell stops dividing or undergoes apoptosis. Therefore, a seriously shortened telomere is an indicator of cell aging. By virtue of the discovery about how chromosomes are protected by telomeres and telomerase, which reveals the mystery of human aging and suffering from serious diseases including cancer, Elizabeth Blackburn from the University of California (San Francisco, US), Carol Greider from Johns Hopkins University (US), and Jack Szostak from Harvard Medical School (US) and were awarded 2009 Nobel Prize in Physiology and Medicine.
[0003] The cancer cell has the property of indefinite division and proliferation, wherein the telomeric DNA is extended by reactivating the expression of the telomerase for most cases. However, the maintenance of the telomere length may also be realized through a telomerase-independent mechanism. In some cancer cells, the telomerase is still in an inhibitory state, wherein the telomeric DNA is extended through a “non-telomerase mechanism”, that is, Alternative Lengthening of Telomeres (ALT). The clinical research indicates that, in general, about 85-90% of the cancer cells are telomerase positive, and about 10-15% of the cancer cells are ALT positive, which means that this two mechanisms are alternative and the cancer cell is in a state of either this or that. For some cancers, the ALT positive rate is higher, for example, the ALT positive rate is nearly 60% for osteogenic sarcomas, nearly 40% for gastric cancers, about 30% for soft tissue sarcomas and astrocytoma, and about 25% for primary brain cancers and glioblastomas. More importantly, the cancer patient with positive ALT often has worse prognosis compared with that with positive telomerase. Therefore, the detection of ALT has a potential of being a reference for monitoring the disease condition and prognosis, and disease treatment. Theoretically, all the cancers can be detected by the combination of ALT detection and telomerase detection.
[0004] At present, the method for detecting and analyzing ALT mainly includes the following:
[0005] 1. Determination of whether the telomere length of a cell can be maintained in the absence of the telomerase activity while the cells are successively divided and proliferated. This determination typically requires the successive division and subculture of the cells for 20-30 passages, and multiple detections of the telomerase activity and the telomere length, thus it is obviously time consuming and labor intensive.
[0006] 2. Detection of the heterozygosity and fluctuation of the telomere length, this process can be accomplished by Southern blotting or FISH. The telomere length varies considerably among the ALT+ cell populations, wherein some cells have quite long telomere, and some have quite short telomere. The clinical specimen generally comprises a mixture of cancer cells/tissues and normal cells/tissues, and the telomere lengths in these two types of population are significantly different from each other, which causes difficulty to the determination of the ALT+ cells. Such detection suffers from complex operations and low sensitivity, for which at least 1000 cells are required.
[0007] 3. Detection of ALT-related PML nucleosome. Copolymerization of telomeric DNA with PML protein is detected by probe hybridization in combination with immunofluorescence/immunohistochemistry. The PML nucleosome obtained from this copolymerization is one of the characteristics of ALT cells. Such detection suffers from complex operations and low sensitivity, for which about 1000 cells are required.
[0008] 4. Detection of recombinant telomeric DNA structure with ALT characteristic. The T-loop structure formed by the recombination of ALT is detected by 2-D electrophoresis technology, which requires about 1×10 7 cells; and the C-loop is assayed by using a highly progressive φ29 DNA polymerase with the circular telomeric TC-ssDNA having characteristic of ALT as a template to synthesize high molecular weight telomeric TG-ssDNA, and the result is assayed by pulse electrophoresis and probe hybridization. Such detection has a sensitivity up to 1000 cells or higher, but requires the use of radioactive isotope, which is not suitable for clinical generalization.
[0009] TC-ssDNA (Telomeric C-single stranded DNA) is a single stranded DNA formed of the CCCTAA unit complementary to the repeat TTAGGG of telomeric G, which generally exists as an extrachromosomal circular DNA, is a specific marker of the ALT+ cells, and it does not exist in normal cells or telomerase positive cancer cells. Therefore, the presence of the ALT+ cells can be determined by detecting whether TC-ssDNA is present. PCR amplification has a quite high sensitivity in nucleic acid detection, so PCR amplification of TC-ssDNA will be a highly sensitive method for detecting ALT+ cells. However, because TC-ssDNA contains repeat CCCTAA sequence, and an upstream and a downstream primer recognition site are necessary for a PCR process, accordingly the TC-ssDNA cannot be used directly as a template for PCR amplification. In the present invention, the template probe is amplified by PCR by binding TC-ssDNA to the anchor probe and inhibiting the cleavage to the template probe through competitive binding, and the result of PCR amplification indicates the presence of TC-ssDNA, thereby the rapid and simple detection of the ALT+ cells with high sensitivity can be achieved.
SUMMARY
[0010] An object of the present invention is to provide a method for amplification of probed-templates through binding of telomeric C-ssDNA (ABTC), and a kit for detecting alternative lengthening of telomere (ALT) by using the method.
[0011] The following technical solutions are employed in the present invention.
[0012] A method for amplifying probed-templates through binding of telomeric C-ssDNA (TC-ssDNA) (ABTC) is provided, which comprises the following steps:
[0013] An anchor probe T is fixed into a reaction tube to obtain an anchor PCR tube. The sequence of the anchor probe T is a repeat sequence of the G sequence, that is, (TTAGGG) n , wherein n is an integer from 6 to 10, and it can be complementarily bound to TC-ssDNA to give a duplex, and the Tm value of this duplex is designated as Tmt. The anchor probe T may be fixed by a conventional method in the art, and the solid matrix for immobilizing the anchor probe T may be a plastic centrifuge tube, magnetic bead, gel particle or other solid matrix that adsorbs and binds nucleic acid.
[0014] Preferably, the anchor PCR tube fixed with the anchor probe T is prepared as follows: 50 μl of a TBST buffer containing 0.1 pmol biotinylated anchor probe T is added to a 0.2 ml thin-wall PCR tube coated with streptavidin and stood at 37° C. for 1 hr. The liquid in the tube is aspirated off, and 100 μl of TBST buffer is added, pipetted, and the liquid is aspirated off. The tube is repeatedly washed 3 times, and then the liquid is aspirated off. 100 μl of TE buffer is added and the liquid in the tube is then aspirated off, the tube is sealed and stored at −20° C. for later use.
[0015] (2) A template probe G is synthesized, in the middle part thereof is a repeat sequence of the G sequence, namely, (TTAGGG) (n−1) (wherein n is the same as described in Step (1), that is, the repeat sequence here contains one less repetitive than that in Step (1)); and both ends of this template probe G are the PCR primer sequences of telomerase. An enzyme cleavage site is located between the G sequence and the primer sequence at one end, and this end is marked as end A. The template probe G can be complementarily bound to TC-ssDNA to give a duplex, wherein the Tm value thereof is designated as Tmc.
[0016] (3) An inhibitory probe S is synthesized, which is complementary to the region of the enzyme cleavage site at the end A of the template probe G. The inhibitory probe S can be complementarily bound to TC-ssDNA to give a duplex, wherein the Tm value thereof is designated as Tms. Tmc is 5° C. lower than Tmt, and 20-25° C. higher than Tms.
[0017] (4) A double-stranded DNA sequence is formed by the template probe G and the inhibitory probe S, and this DNA sequence designated as dsGS. The inhibitory sequence S can be bound to the template probe G to give a duplex, and the duplex has a Tm value of 20° C. lower than that of the duplex formed by template probe binding bound to TC-ssDNA. When the inhibitory sequence S is bound to the template probe G, a complete BamHI recognition site is formed, which can be cleaved by the BamHI enzyme.
[0018] (5) A lysis buffer is added to the sample to be tested, the mixture is repeatedly pipetted, transferred to a centrifuge tube, and placed on ice for 10 min, and centrifuged at 4° C. The supernatant is removed and used as the lysate supernatant. The lysis buffer is conventionally known in the art, which contains a surfactant (e.g. Triton X-100, SDS or the like), a buffer used for releasing DNA from a cell or tissue lysis.
[0019] The sample to be tested may be obtained from tissues or cells, or from clinical specimen such as sputum (luggies) or blood.
[0020] When the sample is obtained from sputum, the lysate supernatant may be prepared as follows: 1-5 ml of sputum and 5-10 ml of a pretreatment buffer are mixed and agitated at 37° C. for 10 min, and centrifuged for 10 min at 4° C. and 5000 rpm. The supernatant is discarded. The pellet is mixed with 200 μl of lysis buffer and repeatedly pipetted, transferred to a 1.5 ml centrifuge tube, placed at room temperature for 10 min, and centrifuged at 15000 rpm for 20 min. The supernatant is removed and used as the lysate supernatant. The pretreatment buffer has a composition of PBS+0.1% (w/vol) DTT.
[0021] When the sample is obtained from cells, the lysate supernatant may be prepared as follows: the cells are cultured in a 24-well plate, and then the culture media is aspirated off. 200 μl of lysis buffer is added, the mixture is repeatedly pipetted, transferred to a 1.5 ml centrifuge tube, placed at room temperature for 10 min, and centrifuged at 15000 rpm for 20 min. The supernatant is removed and used as the lysate supernatant.
[0022] When the test sample is obtained from a tissue, the lysate supernatant may be prepared as follows: about 0.1 cm 3 of a tissue mass is placed into a 1.5 ml centrifuge tube, 200 μl of lysis buffer is added, the tissue mass is smashed, repeatedly pipetted, transferred to a 1.5 ml centrifuge tube, placed at room temperature for 10 min, and centrifuged at 15000 rpm for 20 min, the obtained supernatant is removed and used as the lysate supernatant.
[0023] (6) The lysate supernatant and dsGS are added to the anchor PCR tube, and the hybridization is carried out by incubating for 10-30 min at a temperature that is 5° C. lower than Tmc, at this temperature, the TC-ssDNA is bound to the anchor probe T, meanwhile the dsGS is melted; because the TC-ssDNA is a long cyclic DNA, the template probe G is also bound to the TC-ssDNA, then it is incubated for 10-30 min at a temperature that is 10° C. lower than Tms for hybridization, at this temperature, the remaining template probe G unbound to the TC-ssDNA forms a double-stranded DNA with the inhibitory probe S.
[0024] (7) The liquid is aspirated off, and a PCR reaction solution containing a restriction endonuclease and PCR primers is added, the mixture is incubated for 5-15 min at 37° C. for enzymatic cleavage, then the PCR process is carried out. The obtained PCR product is subjected to fluorescent quantification or analysis by agarose gel electrophoresis. During the detection of ALT, a (blank) lysis buffer is used as a negative control, and it is subjected to the same treatment and analysis as Steps (5)-(7), a positive result is determined if the Ct value of the sample is less than that of the blank lysis buffer and the absolute value of the difference therebetween is greater than or equal to 1. The integrated enzymatic cleavage reaction can prevent not only the amplification of the template probe G that is not hybridized and bound to the telomeric extension sequence, but also the cross contamination caused by the spread of trace amount of PCR product aerosol, thus ensuring the specificity and success rate of the PCR reaction.
[0025] In the case of the cells containing TC-ssDNA, the end A of the template probe G bound to TC-ssDNA cannot be bound to the sequence S, so the intactness of the enzyme cleavage site is destroyed, and the enzymatic cleavage cannot be performed, and the PCR reaction is able to be performed. In the case of the cells containing no TC-ssDNA, the end A of the template probe G is bound to the sequence S, exists as dsGS, which contains complete enzyme cleavable site so it will be enzymatically cleaved prior to the performance of PCR reaction, thus actually the PCR reaction cannot be performed. Therefore, the occurrence of PCR amplification indicates that the cells contain TC-ssDNA, that is, ALT positive cell exists.
[0026] Preferably, the sequence of the anchor probe T is ((TTAGGG) 7 ), i.e.:
[0000]
5′-TTAGGGTTAGGGTTAGGGTTAGGGTTAGGGTTAGGGTTAGGG-3′.
[0027] The sequence of the template probe G is:
[0000]
where the middle shadow part is 6 units of G sequence (TTAGGG) 6 , both ends thereof are PCR primer recognition sites, and the underlined part is a BamHI recognition site.
[0028] The sequence of the inhibitory probe S is: 5′-GTGAC GGATCC CTAACC-3′.
[0029] The PCR primer sequences are:
[0000]
The upstream primer:
5′-CCGTCACCCTGGATGCTGTAGG-3′;
and
The downstream primer:
5′-AAGAGCCGCGAGCGATCCTT-3′.
[0030] Preferably, the lysis buffer in Step (5) has the following composition: 1 mmol/L of EDTA-Na, 1% (v/v) Triton X-100, 150 mmol/L of NaCl, 10% (v/v) glycerol, 0.1 mg/ml fish sperm DNA (commercially available), and 10 mmol/L Tris-HCl (pH7.5) as a solvent.
[0031] Preferably, the PCR reaction solution (PCR buffer+dNTP+SYBR Green I+Taq enzyme+BamHI+PCR primers) in Step (7) has a composition of: 50 mmol/L KCl, 1.5 mmol/L MgCl 2 , 0.2 mmol/L dNTP, 0.05% Tween 20, 0.4× SYBR Green I (0.4× means that the final concentration of each component in the reaction solution is 0.4 time of that of the 1× SYBR Green I; and the stock solution commercially available from the Microprobe Corp generally has a concentration of 10000×, and is diluted in the PCR buffer to have a final concentration of 0.4× by volume for use), 1 U/50 μl of Taq enzyme, 4 U/50 μl BamHI, 0.2 umol/L of PCR primers, and 10 mmol/L of Tris-HCl (pH 9.0) as the solvent.
[0032] The present invention is further directed to a kit for detecting ALT, which substantially comprises: an anchor PCR tube containing an anchor probe T fixed therein, a template probe G, an inhibitory probe S, PCR primers, a PCR reaction buffer, Taq enzyme and BamHI enzyme. In addition to the above main reagents, the kit may further comprise dNTP, SYBR Green I, or TaqMan probe, as desired by those skilled in the art.
[0033] The sequence of the anchor probe T is:
[0000]
5′-TTAGGGTTAGGGTTAGGGTTAGGGTTAGGGTTAGGGTTAGGG-3′.
[0034] The sequence of the template probe G is:
[0000]
[0035] The sequence of the inhibitory probe S is:
[0000]
5′-GTGAC GGATCC CTAACC-3′.
[0036] The PCR primer sequences include:
[0000]
an upstream primer:
5′-CCGTCACCCTGGATGCTGTAGG-3′;
and
a downstream primer:
5′-AAGAGCCGCGAGCGATCCTT-3′.
[0037] The PCR reaction buffer has a composition of: 50 mmol/L KCl, 1.5 mmol/L MgCl 2 , 0.05% Tween 20, and 10 mmol/L Tris-HCl (pH 9.0) as a solvent.
[0038] Preferably, the kit can further comprise a cell lysis buffer having a composition of: 1 mmol/L EDTA-Na, 1% Triton X-100, 150 mmol/L NaCl, 10% glycerol, 0.1 mg/ml fish sperm DNA, and 10 mmol/L Tris-HCl (pH 7.5) as a solvent.
[0039] The present invention mainly has the following advantages: the method and kit according to the present invention are simple and feasible in operation, have a high specificity and a markedly increased sensitivity in the detection of ALT, and are suitable for use in the detection of cells or tissues derived from various sources including clinical specimens derived from sputum.
BRIEF DESCRIPTION OF THE DRAWINGS
[0040] FIG. 1 is a schematic flow chart of a method according to the present invention, which includes
[0041] Step S0: an anchor probe T (TS) is fixed to a solid matrix (e.g. beads);
[0042] Step S1: the cells are lysed to release the TC-ssDNA, in which the lysis buffer is added with a template probe G (TPB) and an inhibitory probe S (CSC), and the region of TPB binding to CSC includes an enzyme cleavage site (restriction site, RS);
[0043] Step S2: incubation is performed at such high temperature (for example, 55° C. as shown in the figure) that the TC-ssDNA binds to the anchor probe T and the template probe G at this temperature, and then the mixture is incubated at a low temperature (for example, 37° C. as shown in the figure), so that the template probe G unbound to the TC-ssDNA is bound to the inhibitory probe S;
[0044] Step S3: after aspiration off, a RE/PCR system is added, and the obtained mixture is incubated at 37° C., during which the template probe G bound to the TC-ssDNA cannot be enzymatically cleaved and is kept intact; and the template probe G bound to the inhibitory probe S is enzymatically cleaved; and
[0045] Step S4: the PCR reaction is carried out and the template probe G is amplified, the result indicates the presence of TC-ssDNA.
DETAILED DESCRIPTION
[0046] The present invention will be described in further detail with reference to specific examples. However, the protection scope of the present invention is not limited thereto.
EXAMPLE 1
Removal of the Interference with PCR from Trace Amount of dsGS by ABTC System Integrated with BamHI Enzyme
[0047] The sequence of the anchor probe T is:
[0000]
5′-TTAGGGTTAGGGTTAGGGTTAGGGTTAGGGTTAGGGTTAGGG-3′.
[0048] The sequence of the template probe G is:
[0000]
[0049] The sequence of the inhibitory probe S is:
[0000]
5′-GTGAC GGATCC CTAACC-3′.
[0050] The sequences of the PCR primers are:
[0000]
upstream primer:
5′-CCGTCACCCTGGATGCTGTAGG-3′;
and
downstream primer:
5′-AAGAGCCGCGAGCGATCCTT-3′.
[0051] Preparation of anchor PCR tube: 50 μl of TBST buffer containing 0.1 pmol of biotinylated anchor probe T was charged into a 0.2 ml thin-wall PCR tube coated with streptavidin and stood at 37° C. for 1 hr. The liquid in the tube was aspirated off, and 100 μl of TBST buffer was added, the mixture was pipetted, and the liquid was aspirated off. The tube was repeatedly washed for 3 times, and then the liquid was aspirated off. 100 μl of TE buffer was added and the liquid in the tube was aspirated off. The tube was sealed and stored at −20° C. for later use.
[0052] The template probe G and the inhibitory probe S were dissolved in separated TE buffer respectively. 2 nmol/L of template probe G and 2 nmol/L inhibitory probe S were mixed, and incubated at 55° C. for 10 min and then at 37° C. for 10 min to obtain the dsGS with final concentration of 1 nmol/L, a part of which was taken and diluted to 0.01 nmol/L.
[0053] The PCR reaction solution (RE/PCR system) had a composition of: 50 mmol/L KCl, 1.5 mmol/L MgCl 2 , 0.2 mmol/L dNTP, 0.05% (vol/vol) Tween20, 0.4× SYBR Green I, 1 U/50 μl Taq enzyme, 0.2 umol/L PCR primers, and 10 mmol/L Tris-HCl (pH 9.0) as a solvent.
[0054] 16 reaction tubes were divided into 8 groups, each having 2 tubes. 20 μl of the above PCR reaction solution was added into each tube in each group. 2 μl of ddH 2 O was added to each tube of Groups 1-4, respectively, and 2 μl of 0.01 nmol/L dsGS was added to each tube of Groups 5-8, respectively. Then, 2 μl of 1 U BamHI in total was added to each tube of Groups 1 and 5 respectively, 2 μl of 2 U BamHI in total was added to each tube of Groups 2 and 6 respectively, 2 μl of 4 U BamHI in total was added to each tube of Groups 3 and 7 respectively, and 2 μl of ddH 2 O was added to each tube of Groups 4 and 8 respectively.
[0055] The reaction was carried out on a fluorescent PCR instrument with the following procedure: 37° C. for 10 min, 94° C. for 5 min, followed by 35 cycles of: 94° C. for 5 sec and 63° C. for 20 sec, and the amplification product was analyzed with SYBR green I fluorescent quantitative assay. The result is shown below.
[0000]
BamHI
Ct1-dsGS
Ct2-dsGS
Ct3-ddH 2 O
Ct4-ddH 2 O
1U
22.48
22.35
30.52
30.76
2U
25.61
25.74
30.44
30.21
4U
30.46
30.28
30.39
30.60
0
17.96
17.79
30.75
30.47
[0056] It can be seen that the Ct value (resulted from the primer dimer) of the ddH 2 O control is greater than 30. In the absence of the BamHI enzyme, the Ct value of the dsGS tube is less than 18, which is far below the value of the control, suggesting that the template probe is amplified. After addition of the BamHI enzyme, the Ct value of the dsGS is obviously increased, suggesting that the intactness of the template probe is destroyed by the cleavage of dsGS by the BamHI enzyme, so that the number of template available to be amplified is declined. When the amount of BamHI is increased to 4 U, the Ct value of the dsGS tube is greater than 30, which is comparable with the value of the control, suggesting that the background arising from the amplification of the remaining small amount of dsTU can be effectively controlled by the RE/PCR system through cleavage.
EXAMPLE 2
Removal of Interference Resulting from Contamination with Trace Amount of PCR Product by ABTC System Integrated with the BamHI Enzyme
[0057] The primer and probe sequences, and the reaction tube were the same as those in Example 1. The amplification product was obtained from Group 8 in Example 1.
[0058] 8 reaction tubes were divided into 4 groups, each group having 2 tubes. 20 μl of the PCR reaction solution (50 mmol/L KCl, 1.5 mmol/L MgCl 2 , 0.2 mmol/L dNTP, 0.05% (vol/vol) Tween 20, 0.4× SYBR Green I, 1 U/50 μl Taq enzyme, 0.2 umol/L PCR primers, and 10 mmol/L Tris-HCl (pH 9.0) as the solvent) was added into each tube of each group. 2 μl ddH 2 O was added to each tube of Groups 1 and 2 respectively, and 2 μl of the amplification product at a dilution of 10 −7 was added to each tube of Groups 3 and 4 respectively. Then, 2 μl of 4 U BamHI in total was added to each tube of Groups 1 and 3 respectively, and 2 μl of ddH 2 O was added to each tube of Groups 2 and 4 respectively.
[0059] The reaction was carried out on a fluorescent PCR instrument with the following procedure: 37° C. for 10 min, and 94° C. for 5 min, followed by 35 cycles: of 94° C. for 5 sec and 63° C. for 20 sec, and the amplification product was analyzed by SYBR green I fluorescent quantitative assay. The result is shown below.
[0000]
BamHI
Ct-Product
Ct-ddH 2 O
4
30.25
30.68
0
16.34
30.73
[0060] It can be seen that the Ct value (resulted from the primer dimer) of the ddH 2 O control is greater than 30. With respect to the conventional PCR, when no BamHI is added to the system, the Ct value of the amplification product tube is less than 17, which is far below the value of the control, suggesting that the amplification product at a dilution of 10 −7 can cause contamination to the conventional PCR reaction system, resulting in serious false positive results. After addition of 4 U BamHI enzyme, the Ct value of the amplification product tube is greater than 30, which is comparable with the value of the control, suggesting that the false positive results arising from the contamination with the trace amount of amplification product can be effectively controlled by the RE/PCR reaction system integrated with BamHI through cleavage.
EXAMPLE 3
Detection of Human Lung Cancer SK-LU-1 Cells by the ABTC Method
[0061] The primer and probe sequences, the reaction tube, the lysis buffer and the RE/PCR system were the same as those in Example 1. SK-LU-1 was known ALT+ cells and commercially available from ATCC.
[0062] The detection method was as follows:
[0063] The SK-LU-1 cells were cultured in a 24-well plate (at a density of about 10-10000 cells/well), the media was aspirated off. 200 μl of a lysis buffer B (containing 0.1 nmol/L dsGS) was added into each well, the mixture was repeatedly pipetted, transferred to a 1.5 ml centrifuge tube, agitated at room temperature for 10 min, and centrifuged at 15000 rpm for 20 min. The supernatant was removed and used as the lysate supernatant.
[0064] The lysis buffer B had a composition of: 0.1 nmol/L dsGS, 1 mmol/L EDTA-Na, 1% (v/v) Triton X-100, 150 mmol/L NaCl, 10% (v/v) glycerol, 0.1 mg/ml fish sperm DNA (Sigma), and 10 mmol/L Tris-HCl (pH 7.5) as the solvent.
[0065] 2) 50 μL of the lysate supernatant was added to a reaction tube, and incubated at 60° C. for 30 min and then at 37° C. for 10 min.
[0066] 3) After aspiration off of liquid, 50 μl of the RE/PCR reaction system (containing 50 mmol/L KCl, 1.5 mmol/L MgCl 2 , 0.2 mmol/L dNTP, 0.05% Tween 20, 0.4× SYBR Green I, 1 U/50 μl Taq enzyme, 4 U/50 μl BamHI, 0.2 umol/L PCR primers, and 10 mmol/L Tris-HCl (pH 9.0) as the solvent). The amplification was carried out on a PCR instrument with the following procedure; 37° C. for 10 min and 94° C. for 3 min, followed by 35 cycles of: 94° C. for 5 sec and 63° C. for 30 sec, and the amplification product was analyzed by SYBR green I fluorescent quantitative assay.
[0067] 4) The operations in Steps 2)-3) were repeated with the lysis buffer B (containing 0.1 nmol/L dsGS).
[0068] 5) When the Ct value≦29.50, the result was determined to be positive, and when the Ct value>29.50, the result was determined to be negative.
[0069] The result is shown below.
[0000]
Sample
Ct
Results
10 cells
29.37
Positive
100 cells
25.82
Positive
1000 cells
22.39
Positive
10000 cells
18.94
Positive
Lysis buffer
30.15
Negative
[0070] It can be seen that the ALT positive result can be detected in 10-10000 SK-LU-1 cells by the ABTC method.
EXAMPLE 4
Stability of Reaction Tubes Fixed with the Anchor Probe T Prepared in Large Quantity
[0071] The reaction tube prepared above was packaged in a plastic bag, and stored at −20° C.
[0072] The primer and probe sequences, the lysis buffer B, and the RE/PCR system were the same as those in Example 3.
[0073] 24 reaction tubes were divided into 6 groups, each having 4 tubes. After sealing, the tubes were stored at 37° C. for 1, 2, 3, 4, 5, and 6 days, and recorded as Groups 1, 2, 3, 4, 5, and 6.
[0074] 1 ml of the lysate supernatant (containing 0.1 nmol/L dsGS) of 5×1000 SK-LU-1 cells was prepared following the method in Example 3 and used as a positive control; and the lysis buffer B (containing 0.1 nmol/L dsGS) was used as a negative control.
[0075] The operations were as described in Steps 2) and 3) of Example 3, and each group of reaction tubes had 2 positive controls and 2 negative controls.
[0076] When the Ct value was ≦29.50, the result was determined to be positive, and when the Ct value was >29.50, the result was determined to be negative.
[0077] The result is shown below.
[0000]
Ct-Positive
Ct-Positive
Ct-Negative
Ct-Negative
Group
control 1
control 2
control 1
control 2
1
22.63
22.49
30.25
30.36
2
22.41
22.58
30.47
30.30
3
22.52
22.37
30.54
30.38
4
22.68
22.73
30.42
30.65
5
24.93
26.48
30.66
30.31
6
29.85
29.66
29.89
30.11
[0078] It can be seen that after storage at 37° C. for 1-4 days, the reaction tubes fixed with the anchor probe T prepared in large quantity have no influence on the detection results of ALT, but have a serious influence on the detection results after storage at 37° C. for 5 or more days.
EXAMPLE 5
Detection of ALT in Human Osteogenic Sarcoma Cell Line U-2 OS by the ABTC Method
[0079] The primer and probe sequences, the reaction tube, the lysis buffer, the reaction solution, and the RE/PCR system were the same as those in Example 3.
[0080] The detection method was as follows:
[0081] The U-2 OS cells (commercially available from ATCC) were cultured in a 24-well plate (at a density of about 10-10000 cells/well), the media was aspirated off. 200 μl of a lysis buffer (containing 0.1 nmol/L dsGS) was added into each well, the mixture was repeatedly pipetted, transferred to a 1.5 ml centrifuge tube, placed on ice for 20 min, and centrifuged at 15000 rpm for 20 min. The supernatant was removed and used as the lysate supernatant. The following operations were the same as those in Example 3. When the Ct value was ≦29.50, the result was determined to be positive, and when the Ct value was >29.50, the result was determined to be negative.
[0082] The result is shown below.
[0000]
Sample
Ct
Results
10 cells
28.96
Positive
100 cells
25.64
Positive
1000 cells
22.37
Positive
10000 cells
19.08
Positive
Lysis buffer
29.53
Negative
[0083] It can be seen that the ALT positive result can be detected in 10-10000 U-2 OS cells by the ABTC method.
EXAMPLE 6
ABTC Detection Kit for ALT
[0084] A kit of 8 Tests had a composition as shown below.
[0000]
Packing
Component
Function
specification
1) Concentrated
Pretreatment of the sample, and
1 × 1.7 ml
pretreatment buffer
collection, enrichment, and washing
of the cells 50-fold diluted with
ddH 2 O before use
2) Lysis buffer
Lysis of cells, and negative control
1 × 1.7 ml
Direct use
3) RE/PCR
Enzymatic cleavage and PCR
1 × 0.45 ml
reaction solution
proliferation Direct use
4) Positive control
Lysate supernatant of 1000 freshly
1 × 0.12 ml
frozen SK-LU-1 cells
Direct use
5) reaction tube
Fixed with telomerase primer
1 × 8
Direct use
6) Membrane seal
Sealing the reaction tube
1
Direct use
7) Instruction
Operation instructions and notices
1
[0085] The concentrated pretreatment buffer had a composition of: 50×PBS+50 g/L DTT, and contained 1×PBS+1 g/L DTT after 50-fold dilution. The composition of 1×PBS was: NaCl 137 mM, KCl 2.7 mM, Na 2 HPO 4 10 mM, KH 2 PO 4 1.8 mM, and distilled water was used as the solvent.
[0086] The primer sequence, the lysis buffer, the reaction tube, and the RE/PCR reaction solution were the same as those in Example 3.
[0087] The operation steps were as follows:
[0088] The kit was removed from a frozen storage environment, thawed at room temperature, and temporarily stored at 4° C.
[0089] The concentrated pretreatment buffer was 50-fold diluted with 83 ml ddH 2 O, to give a pretreatment buffer that was temporarily stored at 4° C.
[0090] A sample was collected, which might be cultured cells and tissues, or sputum, whole blood (supplemented with an anticoagulant), and urine.
[0091] The amount of the sample was recommended to be about 10-10 6 cultured cells, about 0.1 cm 3 tissue mass, about 2 ml of sputum, about 0.5 ml of whole blood, and about 10 ml of urine.
[0092] The sample was pretreated as follows: The cells cultured in suspension were collected by centrifugation, and then re-suspended in 10 ml of the pretreatment buffer. The tissue mass was soaked in 10 ml of the pretreatment buffer, and chopped. The sputum was agitated with 10 ml of the pretreatment buffer at 37° C. for about 10 min until the sputum was completely dissolved. 10 ml of the pretreatment buffer was directly added to the whole blood. After centrifugation of the urine, the pellet was re-suspended in 10 ml of the pretreatment buffer. The materials obtained above were all further centrifuged, the supernatant was discarded, and the pellet was carried on next step.
[0093] 4) The lysis buffer was added to the pellet in an amount of 200 μl/sample, the mixture was repeatedly pipetted, transferred to a 1.5 ml centrifuge tube, placed at room temperature for 10 min, and centrifuged at 15000 rpm for 20 min.
[0094] 5) 50 μl of the lysate supernatant was added to the reaction tube, and incubated at 60° C. for 30 min and then at 37° C. for 10 min.
[0095] 6) The liquid was aspirated off, and then 50 μl of the RE/PCR reaction system (containing the PCR buffer, 0.2 μmol/L PCR primers, 0.2 mmol/L dNTP, 1 U Taq enzyme, and 4 U BamHI) was added. The amplification was carried out on a PCR instrument with the following procedure: 37° C. for 10 min and then 94° C. for 3 min, followed by 35 cycles of: 94° C. for 5 sec and 63° C. for 30 sec, and the amplification product was analyzed by SYBR green I fluorescent quantitative assay.
[0096] 7) A negative control and a positive control were set in place of the lysate supernatant, and used in Steps 5)-6).
[0097] 8) When the Ct value was ≦29.50, the result was determined to be positive, and when the Ct value was >29.50, a negative result was determined.
EXAMPLE 6
Detection of ALT in Immortalized Human Fibroblast Cell Line SUSM-1 with the ABTC Detection Kit for ALT
[0098] The cells (commercially available from ATCC) were subcultured in laboratory. The SUSM-1 cells were cultured in a 24-well plate (at a density of about 1-10 6 cells/well). The kit and operation steps were as described in Example 5. The lysis buffer was used as a negative control and the lysate supernatant of 1000 SK-LU-1 cells was used as a positive control.
[0099] When the Ct value was ≦29.50, a positive result was determined, and when the Ct value was >29.50, a negative result was determined. The result is shown below.
[0000]
Sample/Control
Ct
Results
1
cell
29.24
Positive
10
cells
27.11
Positive
100
cells
23.52
Positive
10 3
cells
19.34
Positive
10 4
cells
16.15
Positive
10 5
cells
15.98
Positive
10 6
cells
15.66
Positive
Negative control
30.79
Negative
Positive control
22.38
Positive
[0100] It can be seen that the ALT positive result can be detected in 1-10 6 SUSM-1 cells with the ABTC kit. However, when the cell number in the sample reaches to or exceeds 10 4 , the Ct value does not decline obviously, suggesting that the amplification limiting factor varies from TC-ssDNA to the template probe, that is, the template probe is completely adsorbed and bound. Therefore, the number of the PCR template is not increased any more with increasing TC-ssDNA in the cells.
EXAMPLE 7
Detection of ALT in Human Osteogenic Sarcoma Cell Line G-292 with the ABTC Detection Kit for ALT
[0101] The cells (commercially available from ATCC) were subcultured in laboratory. The G-292 cells were cultured in a 24-well plate (at a density of about 10-10 5 cells/well). The kit and operation steps were as described in Example 5.
[0102] When the Ct value was ≦29.50, a positive result was determined, and when the Ct value was >29.50. a negative result was determined. The results are shown below.
[0000]
Sample/Control
Ct
Results
10
cells
27.79
Positive
100
cells
24.25
Positive
10 3
cells
19.67
Positive
10 4
cells
16.20
Positive
10 5
cells
15.93
Positive
Negative control
30.13
Negative
Positive control
22.63
Positive
[0103] It can be seen that the ALT positive result can be detected in 10-10 5 G-292 cells with the ABTC kit, and in this range, the higher the cell number is, the lower the Ct value is, suggesting that the ABTC detection for ALT is of great value in quantitative detection.
EXAMPLE 8
Detection of ALT in Human Osteogenic Sarcoma Cell Line SAOS-2 with the ABTC Detection Kit for ALT
[0104] The cells (commercially available from ATCC) were subcultured in laboratory. The SAOS-2 cells were cultured in a 24-well plate (at a density of about 10-10 5 cells/well). The kit and operation steps were as described in Example 5. When the Ct value was ≦29.50, a positive result was determined, and when the Ct value was >29.50, a negative result was determined.
i. The result is shown below.
[0000]
Sample/Control
Ct
Results
10
cells
26.73
Positive
100
cells
23.35
Positive
10 3
cells
20.09
Positive
10 4
cells
16.68
Positive
10 5
cells
15.79
Positive
Negative control
30.42
Negative
Positive control
22.53
Positive
[0106] It can be seen that the ALT positive result can be detected in 10-10 5 SAOS-2 cells with the ABTC kit, and in this range, the higher the cell number is, the lower the Ct value is, suggesting that the ABTC detection for ALT is of great value in quantitative detection.
EXAMPLE 9
Detection of ALT in Sputum Specimen from Lung Cancer Patient with the ABTC Detection Kit for ALT
[0107] 20 lung cancer patients were in stage I as diagnosed by needle biopsy of tissues, and had not received an operation. The sputum was freshly collected in the morning.
[0108] The kit and operation steps were as described in Example 5.
[0109] When the Ct value was ≦29.50, a positive result was determined, and when the Ct value was >29.50, a negative result was determined.
[0110] Among the 20 lung cancer patients, 3 were detected to be ALT positive, and 17 were ALT negative. 2 normal person (who had sputum due to smoking, and were healthy by recently physical examination) control were detected to be ALT negative.
[0000]
Sample/Control
Ct
Results
Negative control
30.52
Negative
Positive control
22.69
Positive
Lung cancer patient
29.76
Negative
JFK-ZJL-201
Lung cancer patient
30.29
Negative
JFK-ZJL-202
Lung cancer patient
30.73
Negative
JFK-ZJL-203
Lung cancer patient
30.44
Negative
JFK-ZJL-204
Lung cancer patient
21.81
Positive
JFK-ZJL-205
Lung cancer patient
29.55
Negative
JFK-ZJL-206
Lung cancer patient
31.38
Negative
JFK-ZJL-207
Lung cancer patient
30.20
Negative
JFK-ZJL-208
Lung cancer patient
29.95
Negative
JFK-ZJL-209
Lung cancer patient
30.57
Negative
JFK-ZJL-210
Lung cancer patient
31.22
Negative
JFK-ZJL-211
Lung cancer patient
29.88
Negative
JFK-ZJL-212
Lung cancer patient
30.74
Negative
JFK-ZJL-213
Lung cancer patient
20.54
Positive
JFK-ZJL-214
Lung cancer patient
30.86
Negative
JFK-ZJL-215
Lung cancer patient
30.19
Negative
JFK-ZJL-216
Lung cancer patient
24.41
Positive
JFK-ZJL-217
Lung cancer patient
30.97
Negative
JFK-ZJL-218
Lung cancer patient
29.78
Negative
JFK-ZJL-219
Lung cancer patient
30.66
Negative
JFK-ZJL-220
Normal individual JFK-ZJN-001
30.49
Negative
Normal individual JFK-ZJN-002
30.68
Negative
[0111] It can be seen that the ALT positive result can be detected in fresh sputum from some lung cancer patients with the ABTC detection kit.
EXAMPLE 10
Detection of ALT in Surgically Removed Gastric Cancer Tissues with the ABTC Detection Kit for ALT
[0112] The surgically removed tissues from 12 gastric cancer patients were frozen at −80° C. About 30 mg of frozen gastric cancer tissue was clipped by sterilized ophthalmic scissors. 10 ml of the pretreatment buffer was added, and centrifuged. The supernatant was discarded. 200 μl of the lysis buffer was added, and agitated at room temperature for 10 min. The following operations were carried out as described in Example 5. The kit was the same as Example 5. When the Ct value was ≦29.50, a positive result was determined, and when the Ct value was >29.50, a negative result was determined.
[0113] The tissues from 5 gastric cancer patients were detected to be ALT positive, and the tissues from 7 gastric cancer patients were detected to be ALT negative.
[0000]
Sample/Control
Ct
Result
Negative control
30.62
Negative
Positive control
22.45
Positive
Gastric cancer patient
30.24
Negative
JFK-ZJG-001
Gastric cancer patient
29.78
Negative
JFK-ZJG-002
Gastric cancer patient
20.55
Positive
JFK-ZJG-003
Gastric cancer patient
21.37
Positive
JFK-ZJG-004
Gastric cancer patient
24.87
Negative
JFK-ZJG-005
Gastric cancer patient
30.14
Negative
JFK-ZJG-006
Gastric cancer patient
29.71
Negative
JFK-ZJG-007
Gastric cancer patient
30.77
Negative
JFK-ZJG-008
Gastric cancer patient
25.34
Positive
JFK-ZJG-009
Gastric cancer patient
27.17
Positive
JFK-ZJG-010
Gastric cancer patient
29.62
Negative
JFK-ZJG-011
Gastric cancer patient
27.48
Positive
JFK-ZJG-012
[0114] It can be seen that the ALT positive result can be detected in surgically removed frozen cancer tissues from some gastric cancer patients with the ABTC detection kit.
EXAMPLE 11
Detection of ALT in Human Lung Cancer Cell Line A549 with the ABTC Detection Kit for ALT
[0115] The cells (commercially available from ATCC) were subcultured in laboratory. The A549 cells were known telomerase positive and ALT negative cells, which were cultured in a 24-well plate (at a density of about 10-10 5 cells/well). The kit and operation steps were the same as Example 5. When the Ct value was ≦29.50, a positive result was determined, and when the Ct value was >29.50, a negative result was determined. The result is shown below.
[0000]
Sample/Control
Ct
Result
10
cells
30.23
Negative
100
cells
30.65
Negative
10 3
cells
30.42
Negative
10 4
cells
30.57
Negative
10 5
cells
30.28
Negative
Negative control
30.76
Negative
Positive control
22.65
Positive
[0116] It can be seen that the 10-10 5 A549 cells are all ALT negative as detected by ABTC, further confirming the specificity of the ABTC method for detecting ALT.
EXAMPLE 12
Replacing TaqMan Probe with SYBR Green I had no Influence on Detection of ALT by the ABTC Method
[0117] The primer and probe sequence, the reaction tube, the lysis buffer, and the RE/PCR system were the same as those in Example 3. In the RE/PCR system, the SYBR green I was replaced by 0.5 μmol/L TaqMan probe (having a sequence of 5′FAM-CCTAACCCTAACCCTAACCCTAACCCTAACCCTA-TAMRA3′). The cells were SK-LU-1 cells. The detection method was the same as Example 5. The FAM fluorescent quantitative assay was used in place of the SYBR green I assay. When the Ct value was ≦30, a positive result was determined, and when the Ct value was >30 or no Ct value is obtained, a negative result was determined.
[0118] The result is shown below.
[0000]
Sample
Ct
Result
Lysis buffer
No Ct
Negative
10 cells
29.36
Positive
100 cells
25.72
Positive
1000 cells
22.43
Positive
10000 cells
19.01
Positive
[0119] It can be seen that the ALT positive result can be detected in 10-10000 SK-LU-1 cells by the ABTC method using TaqMan probe.
|
Provided in the present invention are an affinity mediated amplification method of telomeric C-ssDNA with a template probe and a detection kit using this method for performing alternative lengthening detection of telomeres.
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[0001] This is a divisional of of U.S. patent application Ser. No. 10/327,601, filed Dec. 20, 2002.
FIELD OF THE INVENTION
[0002] This invention relates to methods and systems for the installation of an underground pipelines such as sewer lines using a directional boring machine.
BACKGROUND OF THE INVENTION
[0003] It is well known that installing ‘on grade’ services such as gravity sewer can be very challenging if HDD (Horizontal Directional Drilling) is used as the method of drilling the bore for the pipeline. Typically when these types of pipelines are installed using the open cut method, the pipe is placed, checked for grade, and if necessary, lifted up enough to adjust the grade manually by adding or removing small amounts of bedding material (usually sand or gravel). HDD does not permit fine adjustment after the placement of pipe or any time after the pilot bore is created, therefore the bore path needs to be not only accurate for elevation on each end, but also very straight throughout its length. No opportunity for fine intermediate adjustments is available using currently known HDD methods once the pipe has entered the bore.
[0004] Methods and devices disclosed within the scope of this invention will show that if proper care and attention are used with the novel devices described, it is possible to place on grade pipelines using a combination of HDD equipment and optional impact back-reaming technology. In the discussion that follows, “back reaming” is used to refer to the second stage of the process wherein an expander or hole-opener is pulled backward through the pilot hole to widen the pilot hole and optionally pull the new pipeline into place. However, except as discussed below, according to the invention widening the hole to its final size is done by compaction and not by cutting or reaming per se, and thus is not a reaming operation in the strict sense.
SUMMARY OF THE INVENTION
[0005] A method for installation of an underground pipe according to the invention includes an initial step of boring a pilot hole through the ground at a predetermined grade angle by extending a drill string having a steerable boring bit mounted thereon through the ground. Upon reaching an end location for the pilot hole, the bit is removed from the drill string, and an expander having a diameter greater than the pilot hole is attached to the drill string, which expander is backed by an impact device such as a pneumatic impactor including a striker that delivers repeated impacts to a rearwardly facing surface of the expander, and by a pipe drawn along behind the expander. The expander is pulled back through the pilot hole at the grade angle while the impactor is operated to aid progress of the expander through the ground and pull the pipe into place behind the expander. Typically in this method the replacement pipe is coupled to a rear end of the expander and the boring bit has a sonde housing containing a sonde attached thereto to indicate to an operator the orientation of a steering face on the boring bit. Preferably the boring bit has an outer diameter that does not substantially exceed the outer diameter of the sonde housing.
[0006] According to a preferred form of this method, a cutting back reamer is secured to the drill string ahead of the expander, which cutting back reamer has a maximum outer diameter no more than 90% of the maximum outer diameter of the expander. The drill string and cutting back reamer are rotated during the pulling step independently of the expander and impact device, which do not substantially rotate due to a rotatable connection between the cutting reamer and the expander. The cutting back reamer may be configured to permit steering of the cutting reamer, further comprising correcting deviations from grade by steering using the cutting reamer.
[0007] According to another aspect of the invention, a method for installation of an underground pipe includes the steps of boring a pilot hole through the ground at a predetermined grade angle by extending a drill string having a steerable boring bit mounted thereon through the ground, upon reaching an end location for the pilot hole, removing the bit from the drill string and attaching a drill head including a cutting reamer having a diameter greater than the pilot hole to the drill string, which cutting reamer is configured to permit steering when rotated over less than 360 degrees and is backed by a device for pulling a pipe along behind the expander, the device including a rotatable connection whereby the cutting reamer can rotate in unison with the drill string without substantial rotation of the pulling device and pipe, pulling the pipe back through the pilot hole at the grade angle, detecting deviations of the pipe from the grade angle, and steering using the cutting reamer to correct deviations from the grade angle. The cutting reamer preferably has a forwardly tapering, generally conical shape with a cut away steering face on one side thereof, and is mounted non-concentrically relative to the drill string.
[0008] The invention further provides an apparatus for installation of an underground pipe. Such as apparatus includes a forwardly tapering cutting back reamer having front and rear connecting portions, wherein the front connecting portion is configured for attaching the cutting back reamer to a drill string for rotation therewith, and the rear connection portion includes a bearing joint, an expander connected to the cutting back reamer by the bearing joint so that the expander does not substantially rotate as the drill string and cutting reamer rotate, which expander has a larger outer diameter than the cutting back reamer and is configured to form a hole by compaction of surrounding soil, and an impact device including a striker that delivers repeated impacts to a rearwardly facing surface of the expander. Suitable means may be provided for pulling a pipe along behind the expander and impact device. These and other aspects of the invention are discussed in the detailed description that follows.
BRIEF DESCRIPTION OF THE DRAWING
[0009] In the accompanying drawing, wherein like numeral denote like elements:
[0010] FIG. 1 is a schematic diagram of a back reaming operation according to the invention;
[0011] FIG. 2 is a side view of a first apparatus according to the invention;
[0012] FIG. 3 is a cross section taken along the line 2 - 2 in FIG. 2 ;
[0013] FIG. 4 is a front view of the embodiment of FIG. 2 ;
[0014] FIG. 5 is a side view of a second apparatus according to the invention;
[0015] FIG. 6 is a front view of the embodiment of FIG. 5 ;
[0016] FIG. 7 is a cutaway section view of the bearing referenced in FIG. 5 ;
[0017] FIG. 8 is a side view of a third apparatus according to the invention;
[0018] FIG. 9 is a front view of the embodiment of FIG. 8 ;
[0019] FIG. 10 is a lengthwise section along the line A-A in FIG. 9 ;
[0020] FIG. 11 is a side view of a fourth apparatus according to the invention;
[0021] FIG. 12 is the apparatus of FIG. 11 , in partial lengthwise section;
[0022] FIG. 13 is a side view of a fifth apparatus according to the invention;
[0023] FIG. 14 is a lengthwise sectional view of the apparatus of FIG. 13 ;
[0024] FIG. 15 is a side view of a sixth apparatus according to the invention;
[0025] FIG. 16 is a cross-sectional view along the line 16 - 16 in FIG. 15 .
DESCRIPTION OF PREFERRED EMBODIMENTS
[0026] According to the method of the invention, since directional errors created in the pilot bore are often compounded and exaggerated during any currently known back-reaming operation, any operator attempting an on-grade boring method should remember and emphasize these key factors:
[0027] 1. Steering corrections to maintain the desired bore path must be made to hold grade as a first priority, not depth below the immediate ground surface, also called depth of cover. Most HDD transmitters are located in transmitter housings that have bits with non-symmetrical projections that create a bore larger than the sonde housing diameter. When drilling is stopped to read the grade of the transmitter, it is not necessarily at rest with its axis collinear to the axis of the bore. Non-symmetrical bit geometry coupled with the oversize bore induce a grade error that can be considered unimportant for conventional HDD boring, but must be accounted for or eliminated in on-grade boring.
[0028] 2. Steering during pilot hole boring should be done with a bit that is not substantially oversize to the sonde (transmitter) housing behind it. Generally the transmitter housing is larger diameter than the drill string and the bit is larger than the transmitter housing. This geometry enhances the ability to bend the rod within the bore and steer quickly and aggressively, a quality appreciated during conventional HDD operation. As it is never the desire of on grade boring to steer aggressively or radically, it becomes reasonable to reduce the bit size to a diameter approaching that of the sonde housing. This will tend to enhance the goals of the first point outlined above. The primary reason to keep the bore small is to provide a bore that will guide the rod during the back-reaming operation. No steering corrections are normally possible during the back-ream, therefore the pilot hole must be accurate and function to closely guide the back-ream. To accomplish the guiding process, a straight and accurate pilot hole only slightly larger than the drill string rods will assist in keeping the back-reamer on the intended course.
[0029] 3. The back-reaming process must be controlled so as to minimize wander during the pullback. Wander is exacerbated by changing ground conditions, by short reamers and by reamers that are cone shaped and tend to be forced off their path by cobble stones or other randomly placed obstructions. Even if the reamer used (whether impact assisted or of conventional style) is configured to be long in its body length and not of conical shape, care must be taken during its launch into the bore. The designs that will be discussed tend to go straight and do not respond to applied forces quickly, such as the undesirable forces of cobble stones or ground condition variation, or the desirable force provided by the rod. Therefore the reamer should be launched into the pilot bore with the reamer axis and the pilot bore coaxial to each other. This may require a starter or launch pit that has preparation qualities similar to that which would be used to lay on grade pipe. One notable difference is the length of this bedded pit, it need only be as long as the reamer, rather than the length of the entire pipe installation.
[0030] Conventional pneumatic impact moles are generally designed to traverse a straight path along the length of their bore. Three design considerations help achieve this:
[0031] 1. Making the ratio of body length to bore diameter greater tends to stabilize the mole. As an example, a 2.5 inch diameter pneumatic mole will have an overall length (not including hose) of approximately 48 inches, the bore diameter is 2.6 inches, giving a ratio of (48.0/2.6) or 18.5 to 1. This is recognized as an accurate and stable design even without the advantage of an accurate pilot hole to follow. Typically reamers used in HDD have an aspect or length to diameter ratio of 2 or 3 to 1. Use of an 18.5 to one ratio may not be reasonable for typical on grade bore for 8.62″ diameter pipe, however ratios of 3.5 to 1 or even 7 to 1 can yield a usable and effective reamer and are preferred for use in the invention.
[0032] 2. Use of an active (axially movable) head, such as described in U.S. Pat. No. 6,273,201, the entire contents of which are incorporated by reference herein, reduces the tendency of a pneumatic impact mole to wander off course during a free, or unguided bore. It allows the body to stay stationary and not break static friction with the ground while the head accurately punches a bore in a direction exactly along the axis of the elongated body. Static friction between the body and surrounding soil is less likely to result in deflection of the body within the ground. A moving body would more likely deflect as particles are displaced by dynamic friction.
[0033] 3. Use of a stepped profile head as shown in U.S. Pat. No. 6,273,201 tends to result in a lower reaction force vectors not aligned with the bore axis. These radial reaction components, produced by randomly placed cobble stones or changing ground conditions will have a significant effect on deviating the path of the mole. By limiting their magnitude, the mole will tend to maintain its straight course. This same physics applies to an impact device when attached to an HDD drill string.
[0034] According to the invention, one, two or preferably all three of these features are incorporated into the back reamer to be used for on-grade boring.
[0035] Devices currently used to back ream generally function to cut the soil about the pilot bore, mix it with a drilling fluid such as bentonite, and flow the mixed cuttings from the bore. This method is very functional for non-precision bores and has been used to install hundreds of thousands of miles of buried pipe within the last fifteen years. However, only a small percentage of these pipes were specified to have a specific and tightly toleranced grade; usually a specification only calls for a range of depth of cover. The pipe in such a loosely specified installation will typically have both positive and negative slopes over a short distance. While pressurized product flows well through these pipes, gravity induced flow (sewer) needs a constant and narrowly defined negative slope in the direction of intended flow. Water flows downhill, any loss in velocity due to a flat or positive slope will result in loss of velocity. Excessive slope will result in a high water velocity. Both are equally deleterious to the ability to carry solid matter and will ultimately result in flow obstruction and system failure. As a result, the typical grade for an on-grade sewer line installation according to the invention is in the range of about 0.1 to 5 degrees, preferably 0.1 to 3 degrees, and remains constant over the entire run of the pipeline. Storm sewers are similarly graded.
[0036] HDD has many benefits, most notably minimal disruption of the surface over which the pipes or utilities are placed. Its weakness has been its inability to install pipes for gravity-induced flow, or on grade bores. The device and method of the invention outlined below eliminates that weakness.
[0037] Referring to FIG. 1 , after completing an on grade pilot bore 11 , preferably using the bit-transmitter housing arrangement described above wherein the bit is the same diameter or only very slightly larger diameter than the sonde housing at the front end of a drill string 12 , an accurate reamer launch pit 13 must be prepared. This pit 13 will be coaxial with the pilot bore 11 and have a slope at the nominal value of the specified slope. The bottom is preferably filled with a compactable material such as gravel, and be compressed and tamped to provide a stable base 14 . The pit 13 will be long enough so that the product pipe 16 (preferable high density polyethylene or HDPE) bend radius is loose enough to not lift the tail of a reamer 17 from the launch pit base 14 . If desired, an angled approach bore 18 can be used to bring the product pipe 16 to the pit 13 at the desired angle.
[0038] The reamer 17 will be an impact device, preferably actuated by compressed air, though a hydraulic or a shaft-powered impactor (driven by rotation of the drill string, such as described in U.S. Pat. No. 5,782,311, issued Jul. 21, 1998, the entire contents of which are incorporated by reference herein) may also be used to power the impactor. The reamer body will be long, and if the length engaged by the ground is designated the effective length, the ratio of effective length to bore diameter should be at least about 3.5 to 1, with a ratio of in the range of 3.5:1 to 7:1 being preferred.
[0039] As shown in FIGS. 2-4 , an expander or head 21 of the impact reamer 17 is preferably made to impact the soil in a manner that is decoupled from the drill rod axially, and only in the direction of intended travel. “Decoupled” in this instance means the head moves forwardly relative to the drill string in response to the impact from the impact tool without transmitting more than a small fraction of the impact to the drill string. The head 21 preferably has an annular stair-stepped front profile 22 . The elongated body, being included in the effective length, may be merely a sleeve 23 comprised of HDPE trailing the head 21 . It can be part of the pipe 24 or fused thereto, and serves as the member that functions to maintain alignment of the impact hole opener. Sleeve 23 is secured to head 21 by shear bolts set through holes 26 at the rear end of head 21 .
[0040] The impact mechanism 27 operates in substantially the same manner as described in commonly-owned U.S. Ser. No. 09/946,081, filed Sep. 4, 2001, the entire contents of which are incorporated by reference herein. As described therein, mechanism 27 preferably includes a control spool 28 that opens in response to pulling on the drill string ending in starter rod 29 , permitting compressed air from an air passage 31 to enter the mechanism 27 and cause a striker 32 to reciprocate. A pinned joint 33 permits uncoupling of the head 21 from starter rod 29 . Pinned joints and adapters used herein are described in more detail in Wentworth et al. United States Patent Application 20010017222, published Aug. 30, 2001, the content of which is hereby incorporated herein by reference.
[0041] A further option according to the invention, as shown in FIGS. 5-6 , is to perform a nominal amount of material removal using a cutting reamer 41 that is not unlike those used in conventional methods. This cutting reamer 41 , smaller in diameter than the impact reamer 17 , would be situated slightly in front of impact reamer 17 and be turned (rotated) by the drill string. A swivel connection such as a tapered roller bearing joint 42 is disposed between the rear of the cutting reamer 41 and the front of the impact reamer 17 , preferably ahead of the pinned joint 33 and connected thereto by a bearing adapter 35 . The cutting reamer 41 may represent an enlargement of the starter rod and may replace the starter rod in the end-to-end series of components forming the back reamer or hole opener. A starter rod 50 connects cutting reamer 41 to the leading end of the drill string through a further pinned joint 53 , and these parts cooperate to supply compressed air for the impact mechanism back through lengthwise passage 31 . As an optional component, a sonde 56 may be mounted on the inside of plastic sleeve 31 for measuring the grade angle of the product pipe, and the pipe depth and horizontal position. In this embodiment, exhaust from the impact mechanism passes back through the product pipe 24 , typically a water or sewer line.
[0042] Referring now to FIGS. 8-10 , use of cutting or disruption of the soil to one side of the instantaneous path of the impact reamer 17 may be used to correct or deviate the path slightly. While the path may not be severely altered, by using a method similar to that used to steer in rock, a void can be created using a non-concentric or asymmetrical cutting reamer. By using a reamer 51 that has a forwardly angled cutaway face 52 on one side, or is generally off center (as by being non-coaxially mounted relative to the drill string), it is possible to create a void just to one side of the rod axis that will serve to change the path of the impact reamer 17 very slightly. The shape of face 52 can vary substantially; it need not be forwardly tapered. The motion of the rod used to steer would include partial rotation of the cutting reamer 51 (say 270 degrees), then returning to the start position by either rotating backwards or pushing the rod back (thereby shutting off the impact reamer 17 ), and then rotating through the rest of the circle or in the reverse direction. As the impact back reamer 17 always seeks to have a balance of forces acting on it, the partially cut circle, placed off center to the impact reamer, will cause the device to deviate towards the void. This serves to accomplish a minor steering correction.
[0043] Such a system would require a conventional HDD sonde to be placed in or around the cutting back-reamer so that its orientation is known to the operator. A sonde housing 61 is mounted ahead of cutting reamer 51 for holding a second sonde 62 that enables the operator to determine the orientation of the cutting reamer 51 for steering purposes. The first sonde 56 , in addition to performing the functions described above, can be used in combination with second sonde 61 to measure bending of the apparatus in the ground by comparing grade angle at each location.
[0044] The cutting reamer of the invention can also be used by itself, without the aid of an impact reamer, to accomplish on-grade boring. As shown in FIGS. 11 and 12 , a rearwardly extending flange 65 on reamer 51 is connected by a U-shaped shackle 66 to a conventional pipe puller, such as an expanded taper pipe puller 67 . Shackle 66 is inserted through an eye 68 in flange 65 and secured by means of a bolt 69 through an eye 71 in a frontwardly extending flange 72 of pipe puller 67 . Shackle 66 could be replaced by a cable or any similar pulling connector used in the industry. Additionally, it may be desirable to supply the cutting reamer 51 with drilling fluid (such as bentonite) through the hollow drill string. The drilling fluid is ejected from a series of holes 74 on the outer surface of the reamer 51 in a manner well known in the art, which holes communicate with the central passage 31 through the drill head. Cutting reamer 51 may also have teeth and/or spiral grooves ( 76 , FIG. 11 ) which are effective to enhance cutting action.
[0045] If it is desired to use drilling fluid and a pneumatic impact mechanism as well, the apparatus of FIGS. 13 and 14 can be used. In such a case, since the drill string cannot then be used to conduct compressed air, air is conveyed to a modified impact mechanism 27 A from the rear using a hose 77 extending through the product pipe 24 , such as described in connection with the embodiment of FIGS. 20-26 in the foregoing U.S. Ser. No. 09/946,081, filed Sep. 4, 2001. Should a cutting reamer be used with the impact reamer, the impact reamer 17 A of this embodiment can make use of an integral, self regulating on-off switch or device 78 that would prevent the impact reamer from overtaking or impacting the cutting reamer. In some cases, the resistance of the ground itself will act to prevent the impact reamer from traveling too far forward. The connection between the cutting reamer 51 and impact reamer 17 A may be designed to permit a certain amount of relative movement, for example, by interposing a shackle, cable or elastomeric link therebetween so that limited forward movement of the impact reamer can occur relative to the cutting reamer.
[0046] It is also advantageous for purposes of the invention to use an active head that is axially decoupled from both the rod and the elongated body of the impact reamer. Since the head moves in small increments per impact and the stroke of the head with respect to the elongated body is limited, eventually the impact is applied to the body, moving it forward to meet the head. This has the advantage of keeping the body static during most of the applied impact, thereby enhancing straight reaming. This is accomplished, for example, by using a tool such as the one described in the foregoing U.S. Pat. No. 6,273,201 as the impact reamer, or one having a similar movable chisel or head.
[0047] A further variant of the invention is shown in FIGS. 15 and 16 , wherein the cutting reamer is replaced by a can or tubular steerable expander 81 that protects the device from dirt. The front end of expander 81 can have a conical profile 82 with a cutaway steering face 83 , so that expander 81 can be used to steer in much the same manner as reamer 51 , but without a cutting action. A rotary bearing 84 similar to bearing 42 is disposed inside a shaft or mounting adapter 86 connected to the front end of the impact reamer, which in this embodiment has a larger diameter than the steerable reamer. An external hex surface of adapter 86 rotates expander 81 in unison with the sonde housing and drill string.
[0048] In all but one of the concepts described herein, the hole is sized using compaction rather than cutting. Cutting as illustrated above is preferably employed as a means of reducing the amount of work needed to be done by compaction, but ultimately the most stable, straight and accurate bore is made by using impact compaction. The head preferably creates a hole slightly oversize to the product pipe to limit pipe friction. The amount of oversize, derived from experience in pipe bursting activity using impact compaction methods, should produce a hole diameter 12% to 20% greater than the outer diameter of the pipe. An excessively oversize hole will result in loss of grade tolerance, whereas insufficient oversize will limit the length of pipe installed per bore.
[0049] Approximately 80% of the pipe and conduit being placed currently in the U.S. is not grade sensitive. The other 20% is currently normally installed with open digging methods, resulting in disruption, danger and significant surface restoration efforts. The ability to do that 20% within the required tolerances is now possible in accordance with the invention using impact compaction methods coupled with HDD equipment and processes. In particular, the present invention achieves several unique advantages, including:
[0050] (1) hole upsizing while maintaining pilot bore grade and line using impact compaction coupled to a directional drill;
[0051] (2) hole upsizing while maintaining pilot bore grade and line using impact compaction coupled to a directional drill having the impactor decoupled from the drill string in an axial direction and along the direction of intended travel;
[0052] (b 3 ) hole upsizing while maintaining pilot bore grade and line using an air impact compaction reamer coupled to a directional drill having a self-regulating valve system.
[0053] (4) hole upsizing while maintaining pilot bore grade and line using impact compaction directly behind a smaller cutting reamer coupled to a directional drill and having a self-regulating valve system;
[0054] (5) hole upsizing while maintaining pilot bore grade and line using impact compaction coupled to a directional drill where the elongated body has a length to diameter ratio of 3.5 to one or more;
[0055] (6) Use of a drill bit that bores a hole diameter 20% or less oversize to the transmitter housing and or rod or rod upset diameters for the purpose of maintaining a straight bore path during creation of the pilot bore without giving up all ability to steer; and
[0056] (7) A method of using a non axi-symmetric shaped reamer rotated through less than 360 degrees and returned to its starting position for one or more cycles, thereby creating a cavity off set to the axis of the drill string, the purpose being to deviate the path of any sort of hole opening device, preferably an impact reamer.
[0057] The invention as such includes the foregoing, as well as those defined more specifically in the claims that follow.
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A method for installation of an underground pipe includes an initial step of boring a pilot hole through the ground at a predetermined grade angle by extending a drill string having a steerable boring bit mounted thereon through the ground. Upon reaching an end location for the pilot hole, the bit is removed from the drill string, and an expander having a diameter greater than the pilot hole is attached to the drill string, which expander is backed by an impact device such as a pneumatic impactor including a striker that delivers repeated impacts to a rearwardly facing surface of the expander, and by a pipe drawn along behind the expander. The expander is pulled back through the pilot hole at the grade angle while the impactor is operated to aid progress of the expander through the ground and pull the pipe into place behind the expander. Typically in this method the replacement pipe is coupled to a rear end of the expander and the boring bit has a sonde housing containing a sonde attached thereto to indicate to an operator the orientation of a steering face on the boring bit.
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This is a United States national patent application filed pursuant to 35 USC §111(a) claiming priority under 35 USC §120 of/to U.S. Pat. Appl. Ser. No. 61/582,976 filed Jan. 4, 2012 and entitled ARTICLE ORIENTER & ATTENDANT ORIENTATION OPERATIONS, the disclosure of which is hereby incorporated by reference in its entirety.
TECHNICAL FIELD
The present invention generally relates to an article orienter, more particularly, to a mechanism, or assembly/system so characterized, for automated visual article inspection or, such inspection and article manipulation in furtherance of selectively orienting the article, for instance, in advance of packaging the article, as well as operations associated with such article orientation in advance of article packaging.
BACKGROUND OF THE INVENTION
For some packaged articles, whether individual or grouped, a select and/or particular orientation relative to the package, e.g., case, carton, etc., is believed advantageous, or even necessary. By way of non-limiting example, particular label content of the article may be intended for consumer viewing via a carton adaptation which defines a viewing “window” or the like. Thus, in advance of carton formation and article housing or retention therein, a check or inspection of the article orientation is desirable to properly or advantageously place/position the article in relation to the carton for same, e.g., a article may be rotated about an axis of elongation so as to “present” what is intended to be readily discernable indicia for/of the packaged article to a consumer or the like. To the extent that an unacceptable orientation is detected, article manipulation is undertaken until an acceptable orientation is obtained.
While article inspection, via a vision system, and manipulation/orientation, e.g., rotation via a powered belt for article engagement, is known and commercially practiced, it is generally believed that such systems are less than advantageous owing to a general cumbersomeness, less than stellar throughputs, a lack of precision and maintenance difficulties/maintenance frequency rates resulting in unplanned and unwanted processing line downtime. Thus, is believed desirable and advantageous to rethink the current approach to article inspection and manipulation, and to provide an elegant, precise, high throughput operation characterized by a novel device, apparatus, or assembly characterized by initial article observation, and manipulation responsive to a detected status, condition, or orientation, or lack of any one of same, with continued constant or intermittent observation or inspection.
SUMMARY OF THE INVENTION
An article inspection and orientation adjustment assembly is generally provided. The assembly is generally characterized by a primary subassembly operatively linked for travel with a secondary subassembly. The primary subassembly includes a vision system for visually inspecting conveyed articles, and an array of actuators, actuators thereof responsive to detections of the vision system and selectively energizable for conveyed article engagement in furtherance of altering an orientation of the conveyed article. The secondary subassembly includes a friction bar extending along a travel path for the conveyed articles, energization of an actuator of the array of actuators resulting in frictional engagement of an actuated article with the friction bar so as to rotatingly orient the actuated article.
It is contemplated that the subject article inspection and orientation adjustment assembly stand alone, or be part-and-parcel of a larger processing system or line. For example, article inspection and orientation adjustment operations may be advantageously undertaken subsequent to threshold or preliminary article manipulation operations, for the sake of non-limiting illustration, operations such as metering and/or flight bucketing. Moreover, downstream operations such as inspected article packaging, cartoning, etc. is likewise contemplated. More specific features and advantages obtained in view of those features will become apparent with reference to the drawing figures and DETAILED DESCRIPTION OF THE INVENTION.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts, in perspective view, process flow right to left, an illustrative processing line for selectively orienting articles characterized by process segments/stations I-IV as indicated, namely, article ingress (I), initial article manipulations (II), article inspection or article inspection and orientation adjustment (III), and inspected article egress (IV);
FIG. 2 depicts a detailed view of operations attendant to segments I & II of the processing line of FIG. 1 wherein initial article manipulations are undertaken and/or executed in section II, namely, vertical to horizontal article positioning (IIA) and article collating/grouping (IIB);
FIG. 3 depicts, in isolation and with select structures omitted for the sake of clarity, article inspection and orientation adjustment station III of the processing line of FIG. 1 , article flow generally right to left;
FIG. 4 depicts, upstream end view, the article inspection and orientation adjustment station of FIG. 3 ;
FIG. 5 depicts, overhead plan view, the article inspection and orientation adjustment station of FIG. 3 ;
FIG. 6 depicts, below plan view, the article inspection and orientation adjustment station of FIG. 3 ; and,
FIG. 7 depicts area 7 of FIG. 3 , enlarged with an article omitted to reveal underlying details.
DETAILED DESCRIPTION OF THE INVENTION
An advantageous, non-limiting processing line is generally depicted in FIG. 1 . For the sake of non-limiting context, the processing of cylindrical containers, namely, elongate cylindrical containers 10 characterized by a body 12 , an axis of elongation 14 , a shoulder 16 and a capped neck or end 18 are generally shown (e.g., FIGS. 2 & 7 ), with paired and oriented grouping contemplated in advance of packaging the paired and oriented containers. In advance of a discussion of process line and/or processing particulars, a general immediate overview of the processing line and drawings will facilitate same.
Conveyed article processing as depicted in relation to processing line 20 of FIG. 1 commences figure right, segment or station I, article ingress, and concludes figure left, segment or station IV, grouped and oriented article egress. Initial article manipulations are undertaken in/at segment or station II, with grouped article inspections and, as warranted, article orientation adjustment undertaken in/at segment or station III.
As to the initial manipulations, articles 10 may preliminarily be positioned (i.e., repositioned (IIA)), for example and as shown via a handler assembly 30 , so as to assume a horizontal orientation 10 ″ from a vertical, i.e., upright, orientation 10 ′, and/or collated or grouped, in article pairs 10 A as shown ( FIG. 2 ), and advantageously transferred to a container or flight bucket 24 , i.e., “bucketed” (IIB; FIGS. 1 & 2 ). Subsequent processing proceeds via an inspection and orientation adjustment assembly 40 (see e.g., FIG. 3 , and the alternate views thereof with regard to each of FIGS. 4-6 ) generally characterized by operatively united primary 50 and secondary 100 subassemblies which jointly and cooperatively engage articles ( FIG. 7 ) requiring an oriented adjustment.
Notionally, each article of the conveyed, spaced apart article groups undergo real time inspection with select on-the-fly orientation adjustment (e.g., as by article rotation) via the inspection and orientation adjustment assembly 40 ( FIG. 4 ). The assembly advantageously travels synchronously downstream with a first select set of conveyed article groups, all-the-while inspecting, and, as may be necessary, adjusting via the subassemblies thereof, and thereafter quickly returning to an upstream starting point/locus for inspection and, as circumstances warrant, adjustment of a second select set of conveyed article groups, the second select set immediately adjacent and downstream of the first select set of conveyed article groups.
With general reference to FIGS. 1 & 2 , articles 10 are infed via a conveyance system 22 towards and to an initial article manipulation station characterized by handler assembly 30 . Handler system 30 generally operates upon the infed articles so as to establish an advantageous article spacing and/or article metering, and a preferred article travel orientation. The system generally includes a selectively driven screw or auger conveyor 32 , characterized by a drive assembly 34 and a screw or auger flight 36 axially aligned with the conveyed, ingress articles, and a shoe 38 , adjacent and the auger flight 36 and generally intermediate the opposing ends thereof, for receipt of the auger flight metered articles ( FIG. 2 ). Articles 10 are guidingly received by the auger flight 36 , metered thereby and subsequently passed to and through the shoe 38 whereby the articles 10 are transitioned from a vertical 10 ′ to a horizontal 10 ″ orientation. Upon exiting the shoe 38 of handler system 30 , the metered/paired articles 10 A are deposited or otherwise introduced to flight bucket 24 , e.g., a compartmentalized bucket (see also FIGS. 3 & 7 ), for structured retention of an article group (e.g., a pair as shown). As is generally indicated, and advantageously as will become apparent as this disclosure proceeds, bodies 12 of the articles 10 are generally seated within the bucket compartments, with a portion of the capped necks 18 thereof extending beyond the “depth” of the bucket 24 (see e.g., FIG. 4 ) for, as circumstances warrant, manipulation in furtherance of article orientation adjustment at/within process segment or station III.
Referring now to FIG. 3 , and selectively to the particulars of FIGS. 4-7 , there is generally shown preferred, non-limiting inspection and orientation assembly 40 . Primary 50 (i.e., directly driven) and secondary 100 (i.e., indirectly driven) subassemblies, operatively linked via a linkage 90 are generally contemplated for the assembly 40 ( FIG. 4 ), the metered/bucketed article groups 10 A conveyed therebetween as indicated, more particularly, guidingly conveyed between opposingly paired article guides 26 . As previously noted, the assembly is selectively translatable relative to the conveyed articles groups.
As will be subsequently detailed, primary subassembly 50 is generally characterized by a base, e.g., a carriage 52 as shown, a vision system 54 , and a series of spaced apart actuators, e.g., an array of “lifters” 56 as shown, for selectively tilting bucketed articles, with secondary subassembly 100 generally characterized by a base, e.g., a carriage 102 as shown, a “friction” bar assembly 104 for select engagement with an article body 12 during tilting of a bucketed article. The linkage 90 , more particularly, its inherent configuration, geometry, and dimensions, along with the relationship of elements thereof with, to, among and between elements of each of the subassemblies 50 , 100 of inspection and orientation assembly 40 is such that for a given time interval “t,” the distance traveled for the secondary subassembly (“d”) is less than the distance traveled for the primary subassembly (“D”), advantageously, but not necessarily, “d” is about one half “D” so as to impart a frictional engagement for and between a tilted article body and a contact element of the friction bar so as to effectuate a rate of article adjustment, via rotation, which is easily and readily detected/detectable via the optics of the vision system and/or combined optics and actuator control of the primary subassembly.
Primary subassembly 50 of the inspection and orientation assembly 40 includes vision system 54 and the actuator, i.e., lifter, array 56 , each of which are supported by primary carriage 52 and which are in operative communication (i.e., lifters of the lifter array are operatively responsive to detections of the vision system). Carriage 52 , as indicated, is adapted to include a component of a track and track guide system, namely, a pair of track guides 60 which operatively receive a pair of spaced apart tracks 42 of a base 44 of a drive assembly 46 . Carriage 52 is operatively engaged with a driven belt 48 of drive assembly 46 for translation relative to drive assembly base 44 via slot 45 therein/therethrough ( FIG. 3 ).
Vision system 54 generally comprises an array 62 of spaced apart and grouped optical devices 64 , e.g., those supplied by Cognex (Natick, MA, USA) and in the form of a lens and image sensor combination, supported in relation to primary carriage 52 . Each optical device group of the vision system is in overlying registration with a corresponding bucketed article group of the bucketed article groups (see e.g., either of FIG. 4 or 5 ).
Lifter array 56 generally comprises spaced apart groups (e.g., pairs as shown, see e.g., FIG. 3 or 7 ) of actuators, namely, air cylinders 58 as indicated. Cylinders 58 are pneumatically driven in response to a select detected (or undetected/non-detected) condition of the article in sight of an optic detector/reader 64 of vision system 54 . For example, and as contemplated in the present application/process, label indicia of each article of the bucketed articles is to be inspected, more particularly, to the extent that select label indicia or the like is absent from a “present” article orientation view, the article lifter is activated in furtherance of altering the article orientation.
As is best appreciated with reference to FIGS. 3 , 4 & 7 , lifter array 56 further and generally includes a base 66 , upon which actuators 58 are supported, with each actuator 58 equipped with an article engaging member 68 supported by a driven plate 70 or the like. Contemplated interfaces between and among these elements are via conventional mechanical hardware. Article engaging member 68 , advantageously as shown FIG. 7 , includes a periphery 72 characterized by at least one valley, e.g., cup shaped, or, as shown, a sequence of peaks and valleys (e.g., three peaks 73 and two valleys 75 ( FIG. 7 ), i.e., peak/valley/peak/valley/peak), which cradles a portion of the bucketed article, in the context of the instant application, the capped container neck 18 , and permits a sought after rotated article adjustment to the extent article tilting via actuator lifting is called for owing to a sensing of the detected (or non-detected) condition via the vision system. As should be, and as is readily and generally appreciated, primary subassembly 50 is characterized by structural elements depending at least indirectly from carriage 52 thereof so as to selectively support and position each of vision system 54 and lifter array 56 in relation to the conveyed/passing bucketed articles ( FIG. 4 ).
Secondary subassembly 100 (e.g., FIG. 4 ), as previously noted, generally includes carriage 102 and friction bar assembly 104 supported thereby. As the case with primary subassembly 50 , carriage 102 of secondary subassembly 100 , as indicated, is adapted to include a component of track and track guide system, namely, a track guide 106 which operatively receives a track 42 ′ of a secondary base 44 ′ of drive assembly 46 .
Friction bar assembly 104 is advantageously supported by carriage 102 so as to extend thereover and toward primary subassembly 50 , as shown ( FIGS. 4 & 5 ), upon a post 108 /arm 110 combination. Both post height ( FIG. 4 ) and arm depth ( FIG. 5 ) are advantageously adjustable via a key/keyway adaptation of each of the post 108 and arms 110 . Friction bar assembly 104 is advantageously characterized by a friction member or element 112 ( FIGS. 4 & 7 ) which is retained within a frame/frame members 114 and which is generally positioned in a spaced apart condition in relation to bodies 12 of the bucketed articles. As is best appreciated in relation to FIG. 5 , friction bar assembly 104 , more particularly, friction element 112 overlays nine article buckets while vision system 54 , more particularly, optical device array 62 generally overlies a lesser number, namely, seven as shown. Owing to the nature of friction element 112 , and its spaced condition in relation to article bodies 12 , a tilting of an article 10 results in engagement of the article therewith, and, as secondary subassembly 100 is translating/traveling at a slower rate than the conveyed article buckets 24 , rotation of the engaged article and thus an orientated adjustment effectuated, with contact time essentially regulated via the vision system/vision system controller.
With reference now to FIG. 4 , and particular reference to FIG. 6 , linkage 90 is generally shown. Linkage 90 is advantageously characterized by an armature or link bar 92 which is pivotable about an anchored/anchorable end 94 thereof ( FIG. 6 ). A free link bar end 96 , opposite the anchored end 94 , is united to/with primary assembly carriage 52 via a connecting rod 98 . An intermediate portion of link bar 92 is united to/with secondary assembly carriage 102 via a further connecting rod 98 ′. As previously noted, via the instant advantageous common linkage for and between the subassemblies of the inspection and orientation adjustment assembly, more particularly, a 2:1 armature for the linkage, a translation rate of the secondary subassembly is advantageously about 50% of a translation rate of the primary subassembly. Generally, it is believed advantageous to slave the translation rate of the secondary subassembly to the primary assembly, with the travel rate of the former within an range of about 0.25 to 0.75 of the latter.
Finally, since the structures of the assemblies, subassemblies, and/or mechanisms disclosed herein may be embodied in other specific forms without departing from the spirit or general characteristics thereof, some of which forms have been indicated, the embodiments described and depicted herein/with are to be considered in all respects illustrative and not restrictive. Moreover, while nominal processing has be described and detailed, and to some degree alternate work pieces and systems, assemblies, etc. with regard thereto referenced, contemplated processes are not so limited. Accordingly, the scope of the subject invention is as defined in the language of the appended claims, and includes not insubstantial equivalents thereto.
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An article inspection and orientation adjustment assembly is generally provided. The assembly is generally characterized by a primary subassembly operatively linked for travel with a secondary subassembly. The primary subassembly includes a vision system for visually inspecting conveyed articles, and an array of actuators, actuators thereof responsive to detections of the vision system and selectively energizable for conveyed article engagement in furtherance of altering an orientation of the conveyed article. The secondary subassembly includes a friction bar extending along a travel path for the conveyed articles, energization of an actuator of the array of actuators resulting in frictional engagement of an actuated article with the friction bar so as to rotatingly orient the actuated article.
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TECHNICAL FIELD
The present invention relates to conjugated polymers and copolymers for use in optoelectronic devices containing substituent groups that promote charge transport or charge injection. More particularly, the present invention is drawn to conjugated polymers and copolymers with tunable charge injection and transport ability and to optoelectronic devices fabricated with such polymers and copolymers.
BACKGROUND ART
Semi-conducting conjugated polymers combine the features of low cost polymer processing with attractive optoelectronic properties. Electroluminescent devices based on poly(p-phenylene vinylene) (PPV) were first described by Burroughes et al. in 1990 [Burroughes, J. H., et al., Nature, vol. 347, pp. 539-41, 1990]. The light emission in this system is based on the formation of singlet exciton as a result of double charge injection into the emissive polymer. Numerous conjugated polymers have been reported to be highly luminescent materials suitable for light-emission applications [Kraft, A., et al., Angew. Chem. Int. Ed, vol. 37(4), pp. 402-28, 1998]. With appropriate device engineering, PPV based conjugated polymers can also be employed as the active material to produce photovoltaic current under light irradiation. [Granstrom, M., et al., “Laminated Fabrication of Polymeric Photovoltaic Diodes,” Nature, vol. 395 (6699), pp. 257-60, 1998].
An electroluminescent or light-emitting device (LED) is usually obtained by sandwiching a conjugated polymer thin film between two electrodes. In order to see the light emission, at least one of the electrodes should be transparent, and in most cases indium-tin oxide (ITO) coated on either a glass substrate or a plastic substrate is used. ITO is normally used as the anode due to its high work function. A low work function metal, such as magnesium, calcium, or aluminum, is usually used as the cathode metal electrode. Under a forward bias (anode wired to positive and cathode wired to negative), electrons are injected into the lowest unoccupied molecular orbital (LUMO, or the lowest position of the conduction band), and holes are injected into the highest occupied molecular orbital (HOMO, or the highest position of the valence band).
As a result of charge transport, some of the electrons and holes may recombine to form an excited state (called siglet exciton) that is annihilated to produce light emission corresponding to the band gap of the conjugated polymer. When the electrodes and device configuration are fixed, the light emission and emission efficiency of the polymer LED is dependent on the nature of the conjugated polymer.
For most conjugated polymers, hole injection (or p-doping) is more favorable than electron injection (n-doping). The unbalanced charge injection and transporting ability of these conjugated semi-conducting polymers result in low efficiency of polymer LEDs, that is, low conversion of electrons to emitted photons. To enhance electron injection for polymer LEDs, one common method is to use a low work function metal as the anode, such as calcium. One drawback of using calcium is that it is extremely sensitive to air.
One approach to facilitate charge injection and transport is to design double layer polymer LEDs. Such devices can include a charge-transporting layer to facilitate electron injection, coupled with a luminescent polymer layer. The use of an appropriate charge-transporting layer can provide a closer match of the cathode to the LUMO (for electron injection) or a closer match of the anode to the HOMO (for hole injection) to facilitate easy charge injection (electrons or holes) into the active luminescent material. For instance, in a device of ITO/polymer/electron-transporter/A1, the electron-transporting layer can, on the one hand, enhance electron-injection and transporting ability, and on the other hand, block hole penetration to the A1 cathode.
Many researchers have been developing new luminescent polymers with enhanced electron affinity. Adding strong electron affinity groups, e.g., cyano, onto a PPV backbone exemplifies efforts to lower the LUMO of a polymer and enhance the electron injection ability. With enhanced electron injection of luminescent polymers, air stable metals, such as aluminum, can be used without loss of electroluminescent efficiency. [N. C. Greenham et al., Nature, vol. 365, pp. 628-30, 1993.] Other luminescent polymers containing electron deficient heterocycles, like oxadiazoles, oxathiazole, pyridine, etc., have been exemplified as electron transporting and hole blocking materials. [X.-C Li, et al., “Synthesis and Properties of Novel High Electron Affinity Polymers for Electroluminescent Devices,” ACS Symposium Series, vol. 672, pp. 322-44, 1997.] Due to “over tuning” of the electron affinity in these high electron affinity conjugated polymers, hole transporting materials must be used to achieve high efficiency electroluminescence.
To improve the performance of luminescent conjugated polymers with balanced charge injection transporting ability, some researchers have used polycondensation polymerization methods to obtain conjugated polymers containing bipolar pairs of oxadiazoles/triamine [J. Kido, et al., Chem. Lett., p. 161, 1996], oxadiazoles/carbazole [Z. Peng, et al., Chem. Mater., vol. 10, pp. 2086-90, 1998], oxadiazoles/thiophene [W. L. Yu, et al., Macromolecules, vol. 31, pp. 4838-44, 1998], and cyano/triaryl amine [X.-C. Li, et al., Chem Mater., vol 11, pp. 1568-75, 1999]. The general principle of this method can be described in Equation 1, below:
nM1+nM2→(M1M2) n (1)
The success of this method (M1M2) n depended on the selection of a suitable pair of bipolar moieties that provided the desired balance of charge injection/transport ability. Furthermore, polycondensation reactions between two different monomer moieties are not easily or economically used to obtain luminescent polymers with controlled charge transporting ability. Copolymers have been considered as an alternative approach to modify the final polymer properties, such as mechanical strength, and to provide a good balance between rigid strength and flexible toughness of a polymer. However, because the monomers used have been principally vinyls, the resulting polymers are not conjugated polymers. [X.-C. Li, et al., Adv. Mater., vol. 11, p. 898, 1995.]
It will be appreciated that there is a need in the art for conjugated polymers and copolymers that can be synthesized with tailored charge injection and transport ability. It will be further appreciated that there is a need for such conjugated polymers and copolymers in the fabrication of optoelectronic devices.
DISCLOSURE OF THE INVENTION
The present invention is directed to conjugated polymers and copolymers combining strong luminescent properties and balanced charge transporting/injection properties. The present invention also includes methods of manufacturing such polymers and copolymers, and to optoelectronic devices fabricated with such polymers and copolymers.
Contrary to the reaction of equation 1, which requires a 1:1 ratio of monomers M1 and M2, the present invention provides a conjugated luminescent polymer with tunable charge transport prepared according to the following polymerization reaction:
mnM1+nM2→(M1) m (M2) n (2)
wherein M1 is a monomer having at least two reactive functional groups and at least one chemically bonded charge transporting chromophore group possessing electron-withdrawing character and M2 is a monomer having at least two reactive functional groups and at least one chemically bonded charge transporting chromophore group possessing electron-donating character, wherein m and n are stoichiometric quantities of the monomers M1 and M2, respectively, wherein m and n are varied to tune the charge transport property of the conjugated luminescent polymer.
The monomers preferably are aromatic compounds or hetero-aromatic compounds with at least two reactive functional groups. The functional groups are selected to be self-polymerizable and/or co-polymerizable with another co-monomer under certain chemical and physical conditions. The monomers preferably include aromatic or hetero-aromatic ring(s), like aryl, substituted aryl, benzene, substituted benzene, naphthalene, substituted naphthalene, fluorene, substituted fluorene, thiophene, substituted thiophene, pyridine, substituted pyridine, quinoline, substituted quinoline, oxadiazole, triazole, thiazole, benzothiazole, benzothiophene, and/or multiple carbon double bonds such as vinyl, substituted vinyl, acetyne, etc.
By varying the ratio of different monomers (M1, M2, M3, etc.), the total balance between electron and hole transport can be readily tuned as desired. Electron-withdrawing and/or electron-rich groups or chromophores are chemically linked to the conjugated polymers/copolymers as side functional groups. Statistic copolymers of conjugated polymer segments with electron withdrawing and electron-rich side chromophores provide easy fine-tuning of charge transporting/injection ability for the luminescent polymers.
Typical reactive functional groups include, but are not limited to, halide, aldehyde, nitrile methyl, halide methyl, sulfonium methyl, boronic acid, boronic ester, amino, hydroxide, thiol, ethylene, acetyne, trimethyl silane, trimethyl tin, lithium, Grignard group, and chlorosilane. Examples of some currently preferred functional groups include chloromethyl, bromomethyl, and sulfonium methyl which allow 1,6-polymerization by the formation of p-xylylenes to form a conjugated polymer of poly(a rylene vinylene). The reactive functional groups are preferably the same or chemically similar on each monomer to allow polymerization and/or copolymerization reaction between monomers according to the stoichiometric quantity of each monomer. As used herein, chemically similar functional groups mean that the functional groups have the same or analogous chemical reactivity under the equivalent chemical and physical conditions. Similar functional groups also include functional groups that may undergo a chemical change to form the same or very similar reactive intermediates or follow the same chemical reaction mechanism. One example of chemically similar functional groups includes halide substituent groups, such as chloro- and bromo- or other known leaving groups.
The monomer reactants may be chemically linked with one or more functional substituents that enhance either electron transporting or hole transporting. The monomer reactants may also include a solubilizing functional group such as alkyl, alkoxy, silane, aryl, or heteroaryl.
Some typical electron-withdrawing charge transporting chromophore groups that may be used in accordance with the present invention include, but are not limited to, aromatic oxadiazoles, heteroaromatic rings, cyano groups, and mixtures thereof combined with phenyl or vinyl double bonds. Examples of some currently preferred heteroaromatic rings include pyridine, quinoline, oxadiazole and quinoxaline.
Some typical electron-donating charge transporting chromophore groups that may be used in accordance with the present invention include, but are not limited to, benzene, aromatic amines, carbazoles, thiophenes, farans, and mixtures thereof combined with phenyl or vinyl double bonds.
Additional monomer reactants (M3, M4, M5, etc.) can be used in the polymerization reaction. Preferably from two to four monomer reactants are used, but up to ten monomer reactants can be used. When another monomer reactant M3, present at a stoichiometric quantity p, is used the resulting luminescent polymer has the formula (M1) m (M2) n (M3) p . When yet another monomer reactant M4 is used, the resulting luminescent polymer has the formula (M1) m (M2) n (M3) p (M4) q . The monomers M3, M4, etc. have at least two reactive functional groups and at least one chemically bonded charge transporting chromophore group possessing either electron-withdrawing or electron-donating character. The stoichiometric amounts m, n, p, q, etc. are varied to tune the charge transport property of the resulting conjugated luminescent polymer.
The present invention is also directed to organic electronic devices containing the foregoing conjugated semi-conducting polymers. Such devices typically include at least one thin film of the conjugated polymer coupled to a pair of electrodes. Additional thin films of conjugated luminescent polymer can be used. In such cases, one thin film may be configured to promote electron transport and a second thin film may be tuned to promote hole transport. When the organic luminescent device is fabricated with a plurality of thin films of conjugated luminescent polymer, the thin films are preferably tuned to promote balanced electron and hole transport between the first and second electrodes. Typical organic electronic devices include, but are not limited to, a LED, a thin film transistor, a photovoltaic solar cell, an electrochemical luminescent display device, an electrochromic display device, and an electroluminescent device for active flat-panel display applications.
BRIEF DESCRIPTION OF THE DRAWINGS
The file of this patent contains at least one drawing executed in color. Copies of this patent with color drawings will be provided by the Patent and Trademark Office upon request and payment of the necessary fee.
FIG. 1 is a schematic illustration of an energy level diagram for a single layer LED device (solid line) with fine-tuned charge-transporting property. A comparable double layer device having an electron-transport layer is shown with a dotted line.
FIG. 2 is a cross-section illustration of a typical single layer light emitting device, Glass/ITO/Luminescent polymer/A1.
FIG. 3 is a photograph comparing the luminescence of the precursor polymer 6 with the fully converted conjugated polymer 7.
FIG. 4 is a graph of the photoluminescence spectrum of polymer 7.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention provides a process of preparing a luminescent conjugated polymer having directly bonded substituent groups to facilitate charge injection and charge transport functionality. The substituent groups preferably include electron-withdrawing or electron-donating groups. The process of the present invention provides an easy and versatile method to prepare conjugated copolymers having bright luninescence and balanced charge injection and charge transport properties. The conjugated polymer can be coated as a thin film for use in a multi-layer optoelectronic device for luminescent light-emission, such as a light-emitting device (LED) for active flat-panel display applications, an electrochemical light emitting device, an electrochromic display device, and/or photovoltaic devices. The semi-conducting polymer may have a band gap of from 3.4 eV to 2.0 eV, and may comprise a conjugated backbone with strong luminescent property in solution and/or in solid state.
The semi-conducting polymer has at least a conjugated segment (with a conjugation length preferably of at least 5 double bonds) along the backbone, but preferably is fully conjugated. The conjugated backbone provides a highly delocalized π system having efficient luminescent properties and excellent thermal, mechanical, and electrical properties. The backbone preferably consists of aromatic rings and/or substituted aromatic rings, hetero-aromatic rings and/or substituted hetero-aromatic rings, vinyl and/or substituted vinyl. The conjugated polymer may be chemically linked with suitable substitutions that can assist charge injection and transportation, and/or enhance solubility in conventional solvents.
The monomers preferably are aromatic compounds or hetero-aromatic compounds with at least two reactive functional groups. The functional groups are selected to be self-polymerizable and/or co-polymerizable with another co-monomer under certain chemical and physical conditions. The monomers preferably include aromatic or heteroaromatic ring(s), like aryl, substituted aryl, benzene, substituted benzene, naphthalene, substituted naphthalene, fluorine, substituted fluorine, thiophene, substituted thiophene, pyridine, substituted pyridine, quinoline, substituted quinoline, oxadiazole, triazole, thiozole, benzothiazole, benzothiophene, and/or multiple carbon double bonds such as vinyl, substituted vinyle, acetyne, etc. Scheme 1 illustrates some typical monomer units that can be used to prepare the conjugated polymers according to the present invention.
Several charge transporting chromophore units “R” of Scheme 1 are represented in Schemes 2 and 3, below. The charge transporting chromophores preferably include conjugated segments that will be easily electronically reduced (n-doping) or oxidized (p-doping) to form radical cations or radical anions. For hole transporting chromophores, electron donating group(s), heteroaromatic rings, aromatic amine(s) are major constituents. Scheme 2 includes examples of typical hole transporting construction units for hole transporting chromophores that can be substituents of the monomers used to prepare the conjugated polymers within the scope of the present invention. The illustrated compounds are given by way of example only. Persons skilled in the art will appreciate that other known and novel hole transport moieties can be used in the present invention, including, but are not limited to, organic compounds having electron donating properties, such as aromatic amines, carbazoles, thiophenes, poly(N-vinyl-carbazole), polythiophene derivatives, and others.
Electron transporting chromophores are usually composed of highly electron-withdrawing group(s), electron-withdrawing heteroaromatic ring(s), or their combinations. Scheme 3 includes examples of typical electron transporting construction units for electron-transporting chromophores that can be substituents of the monomers used to prepare the conjugated polymers within the scope of the present invention. The illustrated compounds are given by way of example only. Persons skilled in the art will appreciate that other known and novel electron transport moieties can be used in the present invention, including but not limited to, organic compounds containing electron withdrawing properties such as aromatic oxadiazoles, triazoles, and quinolines, or their combination.
The side groups illustrated above that provide charge transporting/injection ability are chemically bonded to the semi-conducting polymer, preferably linked directly with the conjugated backbone, to effectively influence the energy level of the conjugated polymer. With the use of some electron rich groups (Scheme 2) as the side groups, such as aromatic amines, chromophores containing pyrrole and thiophene rings, chromophores containing carbazoles or fused aromatic rings, the HOMO (the highest occupied molecular orbital) is effectively raised and thus to ease hole injection and transporting ability of the conjugated polymer. With the use of some high electron affinity groups (Scheme 3), such as aromatic oxadiazoles, cyano groups, the LUMO (the lowest unoccupied molecular orbital) of the conjugated polymer is effectively lowered and thus raises the ability for electron injection and transporting.
While homo-polymers with both strong luminescent property and charge transporting/injection property may be used as the active layer and/or merely charge transporting layer in the construction of polymer LEDs, copolymers are preferably used as the active layer and/or charge transporting layer. Surprisingly, this invention demonstrates that by means of co-polymerization, the nature of the conjugated polymer can be tuned to provide a strong electron affinity and/or strong electron rich property, and preferably with a balanced electron and hole injection/transporting ability. This allows the fabrication of a single polymer layer LED having a “gradient energy level” that provides high performance similar to a double layer LED.
FIG. 1 shows the energy level diagram for a polymer LED 10 containing a single layer 12 of conjugated polymer having fine-tuned charge transporting property. By contrast, a comparable double-layer device employing a separate electron-transporting layer 14 and emissive polymer layer 16 is shown in dashed lines. The device 10 includes a conventional cathode 20 and anode 22. Line 24 shows a typical energy level gradient for the electron-transporting layer 14, and line 26 shows a typical energy level gradient for the single-layer conjugated polymer layer 12.
The fine-tuning of charge transporting ability between electrons and holes is embodied by changing the electron-withdrawing/electron-rich pair and by changing the ratio of the segments. The co-polymerization type may be represented by equation 2.
mM1+nM2+pM3→(M1) m (M2) n (M3) p (2)
Wherein M1, M2 and M3 are organic molecules having at least two reactive functional groups and at least one chemically bonded side groups that show either electron-withdrawing or electron-rich properties. M3 is a molecule having at least two reactive groups to form conjugated polymer chain. Typical reactive functional groups include, but are not limited to, halide, aldehyde, nitrile methyl, halide methyl, sulfonium methyl, boronic acid, boronic ester, amino, hydroxide, thiol, ethylene, acetyne, trimethyl silane, trimethyl tin, lithium, Grignard group, and chlorosilane. The reactive functional groups are preferably the same or chemically similar on each monomer to allow polymerization reaction between monomers according to the stoichiometric quantity of each monomer. As used herein, chemically similar functional groups mean that the functional groups have similar chemical reactivity under the same chemical and physical condition. Similar functional groups also mean that the functional groups may subject a chemical change to form the same or chemically equivalent reactive intermediates, and follow with the same chemical reaction mechanism. One example of chemically similar functional groups includes halide substituent groups, such as chloro- and bromo-. For instance, a 1,4-bis(bromomethyl benzene) may be used to copolymerize with 1,4-bis(chloromethyl benzene) to generate a copolymer within the scope of the present invention, as illustrated below:
Where R 1 and R 2 are charge transport moieties, such as electron-withdrawing or electron-donating groups.
One useful polymerization reaction that can be used in accordance with the present invention is 1,6-polymerization by the formation of p-xylylenes to form a conjugated polymer of poly(arylene vinylene). A general scheme is depicted as follow:
Where L is a leaving group, such as Cl, Br, I, sulfonium, sulfone, xanthate; and Ar is a charge-transport substituted phenyl, thiophene, furane, naphthalene, and substituted forms thereof. Preferably, the functional groups are selected from chloromethyl, bromomethyl, and sulfonium methyl that allow polymerization under base condition.
The polymers may be synthesized through co-polymerization with several similar monomers with controlled electron-affinity or electron-donating properties.
EXAMPLES
The following examples are given to illustrate various embodiments within the scope of the present invention. These are given by way of example only, and it is to be understood that the following examples are not comprehensive or exhaustive of the many embodiments within the scope of the present invention.
Example 1
The preparation of a PPV luminescent polymer through the sulfonium precursor route.
Synthesis of PPV precursor polymer. PPV sulfonium precursor was prepared according to a modified procedure as follows: Xylylenebis-p,-(tetrahydrothiophenium chloride) (5.0 g, 14 mmol) was dissolved in dry methanol (35 ml) and cooled to 0° C. The solution was degassed by nitrogen bubbling for ca. 20 minutes before the addition of degassed sodium hydroxide solution (0.4 M, 34.3 ml). The solution became viscous during the addition period of 30 minutes. The reaction mixture was stirred at 0° C. for 1 h, and neutralized by adding dilute hydrochloric acid. The polymer solution was dialysed against water over 3 days at 5° C. (water was changed 3 times) to remove inorganic impurities and small molecular weight oligomers. The polymer yield was about 60 %. The polymer solution was ready for spin-coating at 2500 rpm to form thin polymer film.
LED fabrication of PPV polymer. The obtained PPV precursor polymer solution was used to form a colorless uniform thin film by spin-coating on cleaned ITO glass. After spin-coating, the thin film which was thermally converted (at 250° C. for 5 hours under argon) resulting in a fully conjugated PPV film (yellow color). The thickness of the PPV film was about 100 nm. A layer of aluminum film was deposited on top of the PPV film under thermal evaporation (thickness of 1000 nm) to produce a single layer LED device, such as the device illustrated in FIG. 2 . The LED device 30, shown in FIG. 2, includes a clear substrate 32 having an ITO coating that serves as the anode 34. The single layer of luminescent polymer 36 is shown between the ITO anode 34 and the aluminum cathode 38. An electrical potential 40 connects the anode 34 and cathode 38. With such a single layer device and aluminum as cathode, the device emitted dim green light with a maximal wavelength of 525 nm under daylight condition. The measured brightness at a voltage of 5 V was 370 cd/m 2 .
Example 2
The preparation of PPV bonded with electron-transporting aromatic oxadiazole side chromophore, specifically an aromatic oxadiazole substituted PPV was designed and prepared according to Scheme 4.
Synthesis of 2-(4-tert-butyl-phenyl)-5-(-2,5-dimethyl-phenyl)-[1,3,4]oxadiazole (3)
2,5-dimethyl-carboxylic acid benzene (Aldrich, 6.90 g, 46.1 mmol) and 4-t-butylbenzoic hydrazide (Aldrich, 8.86 g, 46.1 mmol) were dissolved in the mixture of phosphorus pentaoxide (2.0 g, 7.0 mmol) and methylsulfonic acid (30 ml) under nitrogen atmosphere. The mixture was heated to 80° C. and stirred for 6 hours. After cooling the mixture to room temperature, it was poured into water (300 ml). The mixture was extracted with ether (3×70 ml), and the combined ether solution was washed with dilute potassium carbonate solution and water respectively. The product was purified by silica flash column chromatography using hexane to hexane/ether (1:3, v/v) subsequently, and a white solid powder was obtained (9.5 g, 68%). The compound was characterized by 1 H NMR and FT-IR.
Synthesis of 2-(2,5-bis-chloromethyl-phenyl)-5-(4-tert-butyl-phenyl)-[1,3,4]oxadiazole (4)
Compound 3 (3.0 g, 9.79 mmol) and N-chloro-succinimide (3.27 g, 24.48 mmol) were dissolved in carbon tetrachloride (20 ml). The mixture was degassed and heated/irradiated by an IR lamp to reflux under argon. After 4 hours, the mixture was cooled to 0° C. The soluble part of the mixture was separated by filtration. Evaporation of the solvent afforded a solid mixture product, which was separated and purified by silica flash column chromatography using hexane to hexane/EtOAC (1:4, v/v) subsequently. The product was obtained as an off-white powder with a yield of 42%. The compound was characterized by 1 H NMR and FT-IR.
Synthesis of (2-(4-tert-butyl-phenyl)-[1,3,4]oxadiazole)-xylylene-bis-p-(tetrahydrothiophenium chloride) (5)
Compound 4 (2.3 g, 6.13 mmol) and tetrahydrothiophene (THT) (2.7 g, 30.65 mmol) were dissolved in methanol (110 ml) and heated to reflux. The mixture was stirred for 14 hours under refluxing condition before cooling down to room temperature. The solvent and the excess of THT were removed by evaporation under vacuum at room temperature, and the product was washed by dry dichloromethane twice (2×10 ml). The product was obtained as a white solid powder with a yield of 75%.
Synthesis of aromatic oxadiazole substituted PPV precursor 6. The preparation procedure was similar as in Example 1, except using 5 as the monomer. The polymer precursor was obtained with a yield of 45%. The precursor polymer 6 presents blue luminescence, and its fully converted conjugated polymer 7 presents bright yellow, as shown in FIG. 3 . FIG. 4 shows the photoluminescent spectrum of the polymer 7.
LED fabrication of OX-PPV polymer. The obtained OX-PPV precursor polymer (6) solution was spin-coated on a cleaned ITO glass substrate to form a colorless uniform thin film which was then thermally converted (at 250° C. for 5 hours under argon) to produce a fully conjugated OX-PPV film (yellow color). The thickness of the OX-PPV film was about 100 nm. A layer of aluminum film was deposited on top of the PPV film under thermal evaporation (thickness of 1000 nm), resulting in a single layer LED device configured as shown in FIG. 2 . Due to the enhancement of electron-transporting ability of the oxadiazole chromophore, the device emitted bright green light with a maximal wavelength of 555 nm under daylight condition. The measured brightness was 650 cd/m 2 at a voltage of 5 V, which is brighter than the standard PPV device as described in Example 1.
Example 3
PPV-OX-PPV copolymer.
Synthesis of PPV-OX-PPV copolymer. The preparation procedure was similar as Example 1, except using 5 and xylylenebis-p-(tetrahydrothiophenium chloride) (1:1 mole ratio) as the monomers (Scheme 5). The co-polymer precursor was obtained with a yield of 65%, which is higher than Example 2. The precursor co-polymer 8 presented blue luminescence, and its fully converted conjugated polymer 9 presented greenish yellow.
LED fabrication of PPV-OX-PPV polymer. The copolymer was used to fabricate single layer device, ITO/PPV-OX-PPV/A1, according to the procedure described in Example 1. More stable and bright, greenish yellow electroluminescence was observed for the copolymer device. Compared with polymer 7, the copolymer has a better film formation property and a well-balanced charge-transporting property, since PPV has a good hole-transporting ability and oxadiazole-substituted PPV (OX-PPV) has enhanced electron-transporting ability. The measured brightness was 950 cd/M 2 at a voltage of 5 V, which is brighter than the OX-PPV device as described in Example 2.
Example 4
Soluble OX-PPV luminescent polymer with electron-transporting side chromophores. To obtain soluble conjugated polymer with electron-transporting ability, a new polymer with a long alkoxyl substituted OX-PPV was prepared according to Scheme 6.
Synthesis of 4-nonyloxy-benzoic acid N′-(2,5-dimethyl-benzoyl)-hydrazide.(12)
2,5-dimethyl-carboxylic acid benzene (Aldrich, 2.56 g, 17.2 mmol) and thionyl chloride (15 ml) was heated to reflux under nitrogen for 4 hours. The extra thionyl chloride was removed by evaporation under vacuum at elevated temperature. The rough acid chloride product was recrystallized from hexane to afford the pure acid chloride (97%). The acid chloride was dissolved in dry chloroform (50 ml), and 4-nonyloxy-benzoic acid hydrazide (4.5 g, 17.02 mmol) was added, followed with the addition of triethyl amine (1.48 g). The mixture was stirred for 10 hours at room temperature, and then poured into ice water (120 ml). The mixture was extracted with ethyl acetate (4×50 ml), and the combined ethyl acetate solution was dried over sodium sulfate. After evaporation of ethyl acetate, the solid powder was purified by re-crystallization in ethanol to give the white hydrazide product (88%, 6.1 g).
Synthesis of 2-(2.5-dimethyl-phenyl)-5-(4-nonyloxy-phenyl)-[1,3,4]oxadiazoles (13)
The hydrazide 12 (6.1 g, 14.96 mmol) was dissolved in POCl 3 (20 ml) and heated to reflux under nitrogen. The mixture was stirred for 4 hours. The extra POCl 3 was removed by evaporation under vacuum. The residue was washed by ice water and recrystallized in ethanol to give the title off-white product (92 %, 5.4 g).
Synthesis of 2-(2,5-bis-chloromethyl-phenyl)-5-(4-nonyloxy-phenyl)-[1,3,4]oxadiazole (14)
The oxadiazole 13 (5.2 g, 13.25 mmol) and N-chlorosuccinimide (3.89 g, 29.1 mmol) were dissolved in carbon tetrachloride (80 ml). The suspension mixture was heated/irradiated by an IR lamp to reflux. The reaction was carried out for 5 hours and cooled down to room temperature. The mixture was filtered, and the filtrate was dried to give a rough white product that was purified by silica flash chromatograph using hexane to hexane/EtOAC (1:3, v/v) to afford the product (42%, 2.58 g).
Synthesis of poly [2-(4-nonyloxy-phenyl)-[1,3,4]oxadiazole-phenylenevinylene](NPOX-PPV) (15)
The monomer 14 (1.5 g, 3.25 mmol) was dissolved in dry tetrahydrofuran (80 ml) under nitrogen. Potassium tert-butoxide solution (1.0 M in THF, 19.5 ml) was added dropwise over 20 minutes into the solution at room temperature. The clear solution became green and viscous within 30 minutes. The mixture was stirred for 24 hours at room temperature under dark condition. The deep green viscous solution was poured into methanol (500 ml) to give bright yellow precipitate which was re-dissolved in minimal THE (10 ml) and precipitated in methanol again (500 ml). The bright yellow polymer was obtained with a yield of 70% (0.89 g). Gel permeation chromatography measurement revealed M n =80,000 and M w =200,000 da.
Example 5
Soluble NPOX-PPV-co-MEH-PPV.
Poly(2-methoxy-5-(2′ethylhexyloxy)-phenylenevinylene) (MEH-PPV) can be prepared according to published method (F. Wudle, et al, ACS Symposium Ser. 455 (1991): 683-686). It is a red luminescent polymer with preferential hole-transporting capability. The copolymer according to Scheme 7 represent a facile method to fine-tune charge-transpsorting capability for a luminescent conjugated polymer. The copolymerization procedure and purification was similar to Example 4, except using two monomers. For a simple example, the monomer ratio was 14:16=2, a copolymer with generally m:n=2 ratio as judged by 1 H NMR revealed a similar ratio for the copolymer. The copolymer 17 appeared bright red and luminesced orange red. Electroluminescence with aluminum as cathode can be readily achieved due to the enhancement of electron-injection/transporting property with the introduction of NPOX-PPV.
The present invention may be embodied in other specific forms without departing from its structures, methods, or other essential characteristics as broadly described herein and claimed hereinafter. The described embodiments are to be considered in all respects only as illustrative, and not restrictive. The scope of the invention is, therefore, indicated by the appended claims, rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.
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Conjugated polymers and copolymers with strong luminescent properties and balanced charge transporting/injection properties are disclosed. Methods of manufacturing such polymers and copolymers and optoelectronic devices fabricated with such polymers and copolymers are disclosed. A conjugated luminescent polymer with tunable charge transport is prepared according to the following polymerization reaction:
mM1+nM2→(M1) m (M2) n
wherein M1 is a monomer having at least two reactive functional groups and at least one chemically bonded charge transporting chromophore group possessing electron-withdrawing character and M2 is a monomer having at least two reactive functional groups and at least one chemically bonded charge transporting chromophore group possessing electron-donating character, wherein m and n are stoichiometric quantities of the monomers M1 and M2, respectively, wherein m and n are varied to tune the charge transport property of the conjugated luminescent polymer. The monomers may include aryl, substituted aryl, and/or multiple carbon double bonds so that when polymerized, the resulting polymer has a conjugated backbone. Additional monomer reactants (M3, M4, M5, etc.) can be used in the polymerization reaction. The stoichiometric monomer amounts are varied to tune the charge transport or other electronic properties of the resulting conjugated luminescent polymer.
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BACKGROUND OF THE INVENTION
The present invention relates generally to the field of cardiac therapy devices, particularly implantable cardioverter-defibrillators (ICDs), and more particularly, to a novel tachyarrhythmia detection (diagnostic) algorithm which can be employed in such devices for discriminating between ventricular and supraventricular tachyarrhythmias.
Implantable cardioverter defibrillators (ICDs) are highly sophisticated medical devices which are surgically implanted (abdominally or pectorally) in a patient to monitor the cardiac activity of the patient's heart, and to deliver electrical stimulation as required to correct cardiac arrhythmias which occur due to disturbances in the normal pattern of electrical conduction within the heart muscle.
Cardiac arrhythmias can generally be thought of as disturbances of the normal rhythm of the heart beat. Cardiac arrhythmias are broadly divided into two major categories, namely, bradyarrhythmia and tachyarrhythmia. Tachyarrhythmia can be broadly defined as an abnormally rapid heart rate (e.g., over 100 beats/minute, at rest), and bradyarrhythmia can be broadly defined as an abnormally slow heart rate (e.g., less than 50 beats/minute). A normal cardiac rhythm (e.g., between 50-100 beats/minute) is referred to as a "sinus rhythm".
Tachyarrhythmias are further subdivided into two major sub-categories, namely, tachycardia and fibrillation. Tachycardia is a condition in which the electrical activity and rhythms of the heart are rapid, but organized. Fibrillation is a condition in which the electrical activity and rhythm of the heart are rapid, chaotic, and disorganized.
Tachycardia and fibrillation are further classified according to their location within the heart, namely, either atrial or ventricular. In general, atrial arrhythmias are not life-threatening, because the atria (upper chambers of the heart) are only responsible for aiding the movement of blood into the ventricles (lower chambers of the heart), whereas ventricular arrhythmias are life-threatening, because if the ventricles become arrhythmic, the heart's ability to pump blood to the rest of the body is impaired. The most serious and immediately life-threatening type of cardiac arrhythmia is ventricular fibrillation, in which the electrical activity of the ventricles becomes so random and chaotic that the heart rapidly becomes unable to pump sufficient blood to sustain life.
In general, tachyarrhythmias which are ventricular in origin are referred to as "ventricular tachyarrhythmias", and tachyarrhythmias which are non-ventricular in origin are referred to as "supraventricular tachyarrhythmias" or "non-ventricular tachyarrhythmias". Supraventricular tachyarrhythmias encompass atrial tachycardia, atrial flutter, and atrial fibrillation.
In general, an ICD continuously monitors the heart activity of the patient in whom the device is implanted by analyzing electrical signals, known as electrograms (EGMs), generated by sensing electrodes positioned proximate the sino-atrial and/or atrio-ventricular node of the patient's heart, and, most advantageously, in the right ventricular apex of the patient's heart. More particularly, contemporary ICDs include waveform digitization circuitry which digitizes the analog EGM produced by the sensing electrodes, and a microprocessor and associated peripheral ICs which analyze the thusly digitized EGM in accordance with a diagnostic or detection algorithm implemented by software stored in the microprocessor. Contemporary ICDs are generally capable of diagnosing (detecting) the various types of cardiac arrhythmias discussed above, and then delivering the appropriate electrical energy/therapy to the patient's heart, in accordance with a therapy delivery algorithm also implemented in software stored in the microprocessor, to thereby convert or terminate the diagnosed arrhythmia.
In this connection, contemporary ICDs are capable of delivering various types or levels of electrical therapy. The first type of therapy is bradycardia and antitachycardia pacing, in which a low level of electrical energy (generally between millionths to thousandths of a joule) is delivered to the patient's heart in order to correct detected episodes of bradycardia or tachycardia, respectively. The second type of therapy is cardioversion, in which an intermediate level of electrical energy (generally between 1-5 joules) is delivered to the patient's heart in order to terminate a detected episode of ventricular arrhythmia (e.g., a detected heart beat in the range of 130-190 beats/minute) or an ongoing episode of tachycardia that antitachycardia pacing has failed to correct or abort. The third type of therapy is defibrillation, in which a high level of electrical energy (generally above 15 joules) is delivered to the patient's heart in order to terminate a detected episode of ventricular fibrillation or an episode of ventricular tachycardia which has degraded into ventricular fibrillation due to failure of cardioversion therapy.
The provision of the above-described different types or levels of therapy is oftentimes referred to in the art as "tiered therapy". In this regard, contemporary ICDs which are capable of delivering tiered therapy are sometimes referred to as combination pacemakers/defibrillators or as implantable cardioverter-defibrillators. As used herein, the terminology "implantable cardiac defibrillator" (ICD) is intended to encompass these and all other forms and types of implantable cardiac devices.
Current-generation ICDs which are capable of delivering tiered therapy provide several advantages over previous-generation ICDs which were only capable of delivering high energy defibrillation therapy. Namely, ICDs which are capable of delivering tiered therapy are generally more energy-efficient, since they can deliver much lower energy therapy, such as antitachycardia pacing and cardioversion, to terminate many arrhythmia events before they degrade into a ventricular fibrillation event. The much higher energy defibrillation therapy is only necessary when these lower energy therapies fail to terminate the arrhythmia. Thus, tiered therapy conserves the energy stored in the battery(ies) of the device, thereby extending the longevity of the device, and also enables a significant portion of potential ventricular fibrillation events to be terminated with lower energy therapy which is much less painful and uncomfortable to the patient.
In such ICDs which are capable of delivering tiered therapy, it is imperative that the detection or diagnostic algorithm employed be reliably accurate, so that the patient's heart condition can be accurately monitored at all times and any arrhythmias promptly and properly diagnosed and treated Coy delivery of the appropriate therapy to terminate or convert the detected arrhythmia). In this regard, there are a number of presently available or known detection algorithms which, for the most part, are quite reliable and accurate.
For example, U.S. Pat. No. 4,971,058, issued to Pless et al. and assigned to the assignee of the present invention, the disclosure of which is incorporated herein by reference, discloses a detection algorithm (hereinafter referred to as "the '058 detection algorithm") which determines the duration of the intervals between successive heartbeats (i.e., cycle lengths between consecutive QRS complexes), and computes a running average of the duration of a prescribed number (e.g., 4) of preceding intervals, referred to as the "average interval", which is re-computed (updated) every interval (i.e., on an interval-by-interval basis).
The '058 detection algorithm also classifies the spectrum of heart rates into several discrete bands which correspond to different cardiac conditions or rhythms. For example, a heart rate of <130 beats per minute could be classified as a normal sinus rhythm (SINUS), a heart rate of 130-160 beats per minute could be classified as a slow tachycardia rhythm (TACH A), a heart rate of 160-200 beats per minute could be classified as a fast tachycardia rhythm (TACH B), and a heart rate greater than 200 beats per minute could be classified as fibrillation (FIB). Since an interval duration can be extrapolated to heart beats per minute, it is apparent that a plurality of interval duration ranges can be selected which extrapolate to ("imply") the corresponding cardiac rhythm bands. On this basis, the detected intervals and average intervals are classified according the cardiac rhythm band corresponding to the interval duration range in which they fall. Thus, an interval (or average interval) that falls into an interval duration range (e.g., >450 msec) corresponding to normal sinus rhythm (SINUS) will be classified as a SINUS interval (or average interval), an interval (or average interval) that falls into an interval duration range (e.g., 380-450 msec) corresponding to slow (low rate) tachycardia (TACH A) will be classified as a TACH A interval (or average interval), an interval (or average interval) that falls into an interval range (e.g., 310-380 msec) corresponding to fast (high rate) tachycardia (TACH B) will be classified as a TACH B interval (or average interval), and an interval (or average interval) that falls into an interval duration range (e.g., <310 msec) corresponding to fibrillation (FIB) will be classified as a FIB interval (or average interval).
In accordance with the '058 detection algorithm, an arrhythmia is detected (diagnosed) in the following manner. More particularly, the RAM or other read/write memory of the device is organized into a plurality of different storage locations, referred to as temporary storage "bins", corresponding to the different cardiac rhythm bands into which the cardiac frequency spectrum is divided. Thus, there is a SINUS bin, a TACH A bin, a TACH B bin, and a FIB bin. At every interval, the determined interval duration and average interval are used (in accordance with the detection algorithm) to "bin" the interval, i.e., to increment the appropriate one of the bins. Each of the bins is assigned a maximum count limit. In this regard, the depth of each bin is determined by its programmed maximum count limit.
The '058 detection algorithm then determines when any of the bins has been counted up to its maximum count limit, i.e., is full. The '058 detection algorithm then returns or enters a diagnosis based on which bin first reaches its programmed maximum count limit. More particularly, if the SINUS bin is filled first, then the patient's cardiac condition is detected to be normal. If the FIB bin is filled first, then a diagnosis of fibrillation is made, and the appropriate defibrillation therapy subsequently delivered in accordance with the therapy delivery algorithm. If the TACH A bin is filled first, then a diagnosis of slow rate tachycardia is made, and the appropriate anti-tachycardia pacing or cardioversion delivered in accordance with the therapy delivery algorithm. If the TACH B bin is filled first, then a diagnosis of high rate tachycardia is made, and the appropriate cardioversion therapy delivered in accordance with the therapy delivery algorithm. An extended high rate (EHR) timer is also used to detect an EHR condition. When the EHR timer times out, a diagnosis of EHR is made, and defibrillation therapy is delivered in accordance with the therapy delivery algorithm. The EHR timer is cleared upon each diagnosis of a normal sinus rhythm or fibrillation. The arrhythmia bins are cleared (reset) upon each diagnosis of a tachyarrhythmia. All bins are cleared upon diagnosis of either a normal sinus rhythm or fibrillation.
The '058 detection algorithm also includes an algorithm section for discriminating between a tachycardia event and a bigeminal rhythm, by determining whether the total number of tachyarrhythmia intervals which were counted during the detection period (i.e., the combined count value of the TACH A, TACH B, and FIB bins) was greater than the total number of sinus intervals which were counted during the detection period (i.e., the count value in the SINUS bin). If the number of tachycardia intervals which were counted during the detection period is not greater than the number of sinus intervals which were counted during the detection period, then the arrhythmia diagnosis is inhibited. Thus, the '058 detection algorithm keeps track of the relative number of sinus intervals and tachycardia intervals during the detection period to prevent a bigeminal rhythm from being inappropriately diagnosed as tachycardia. However, although this "measure of interval altemans" is effective to adequately discriminate between tachycardia and a bigeminal rhythm, it is not capable of reliably distinguishing or discriminating between ventricular and supraventricular tachyarrhythmias, so that the appropriate therapy (or no therapy) can be delivered, for the reasons developed below.
More particularly, ventricular tachyarrhythmias are generally characterized by a large number of consecutive ventricular tachyarrhythmia intervals, and rarely, if ever, during an actual episode of ventricular tachyarrhythmia will there be more than a few (e.g., 1-3) intervening sinus intervals. On the other hand, some supraventricular tachyarrhythmias, in particular atrial fibrillation, are generally more sporadic, in that sinus intervals are typically interspersed with tachyarrhythmia intervals. Thus, atrial fibrillation is generally characterized by variable intervals or interval irregularity. This property of beat-to-beat variation in ventricular intervals during atrial fibrillation has previously been used in an attempt to distinguish atrial fibrillation from ventricular tachycardia. However, in some instances, the intervals may regularize to the extent that a fairly large number of stable tachyarrhythmia intervals occur. If this phenomenon occurs during the detection period or window, then it is quite apparent that an episode of supraventricular tachyarrhythmia could be misdiagnosed as an episode of ventricular arrhythmia.
Obviously, a misdiagnosis of supraventricular tachyarrhythmia as ventricular tachyarrhythmia would result in a subsequent delivery of therapy (treatment) which is inappropriate. If therapy is delivered that is not required it may actually induce an arrhythmia that really does require treatment, and, at a minimum, will result in a waste of the finite amount of energy that the device is capable of delivering over its lifetime, thereby shortening its useful lifetime.
Based on the above, although the presently available detection algorithms such as the '058 detection algorithm discussed above are generally quite sensitive and reliable in detecting ventricular arrhythmias, there still exists a need in the art for a detection method (and cardiac therapy device for implementing the same) which reliably discriminates between ventricular and supraventricular arrhythmias, thereby improving detection specificity. The present invention fulfills this need in the art.
SUMMARY OF THE INVENTION
The present invention encompasses a method for detecting cardiac arrhythmias which includes the steps of detecting a patient's cardiac activity, counting the number of intervals which satisfy a first selected criterion, and producing a sinus interval history count indicative of the number of such intervals which are counted, making a preliminary diagnosis of tachyarrhythmia upon detecting that the cardiac activity satisfies a second selected criterion, and, making a final diagnosis of tachyarrhythmia if the sinus interval history count is less than a selected maximum sinus interval history count, and otherwise, inhibiting a final diagnosis of tachyarrhythmia.
The present invention also encompasses a method for detecting cardiac arrhythmias which includes the steps of detecting a patient's cardiac activity, counting the number of intervals which satisfy a first selected criterion, and producing a sinus interval history count indicative of the number of such intervals which are counted, making a preliminary diagnosis of tachyarrhythmia upon detecting that the cardiac activity satisfies a second selected criterion, determining if the preliminary diagnosis of tachyarrhythmia is proper according to a first measure of interval irregularity, making a qualified preliminary diagnosis of tachyarrhythmia if it is determined that the preliminary diagnosis of tachyarrhythmia is proper according to the first measure of interval irregularity, and otherwise, inhibiting a final diagnosis of tachyarrhythmia, and, if a qualified preliminary diagnosis of tachyarrhythmia is made, then making a final diagnosis of tachyarrhythmia if the sinus interval history count is less than a selected maximum sinus interval history count, and otherwise, inhibiting a final diagnosis of tachyarrhythmia.
In a first preferred embodiment, the method of the present invention includes the steps of monitoring an electrogram representative of a patient's cardiac activity, sensing intervals between successive cardiac events, at every interval, determining the duration of that interval and computing the average duration of a prescribed number of preceding intervals, including that interval, initiating a detection period upon detecting that the computed average duration is less than a prescribed average duration threshold, at every interval after initiation of the detection period, classifying that interval as either a countable tachyarrhythmia interval or a countable sinus interval, based upon the determined duration of that interval and the computed average duration associated with that interval, and further classifying that interval as an absolute sinus interval if either the duration of that interval or the computed average duration associated with that interval is greater than a prescribed duration threshold, counting the number of absolute sinus intervals, counting the number of countable tachyarrhythmia intervals and countable sinus intervals, terminating the detection period and making a preliminary diagnosis of tachyarrhythmia if the counted number of countable tachyarrhythmia intervals exceeds a prescribed maximum tachyarrhythmia count before the counted number of countable sinus intervals exceeds a prescribed maximum sinus interval count, and, making a final diagnosis of tachyarrhythmia if the counted number of absolute sinus intervals during the detection period is less than a prescribed maximum absolute sinus interval count, and otherwise, inhibiting diagnosis of tachyarrhythmia.
In a second preferred embodiment, the method of the present invention includes the steps of monitoring an electrogram representative of a patient's cardiac activity, sensing intervals between successive cardiac events, at every interval, determining the duration of that interval and computing the average duration of a prescribed number of preceding intervals, including that interval, and classifying that interval as either a countable tachyarrhythmia interval or a countable sinus interval, based upon the determined duration of that interval and the computed average duration associated with that interval, and further classifying that interval as an absolute sinus interval if either the duration of that interval or the computed average duration associated with that interval is greater than a prescribed duration threshold, counting the number of absolute sinus intervals, counting the number of countable tachyarrhythmia intervals and countable sinus intervals, terminating the tachyarrhythmia detection period and making a preliminary diagnosis of tachyarrhythmia if the counted number of countable tachyarrhythmia intervals exceeds a prescribed maximum tachyarrhythmia count before the counted number of countable sinus intervals exceeds a prescribed maximum sinus interval count, and determining if the preliminary diagnosis of tachyarrhythmia is proper according to a first measure of interval irregularity, making a qualified preliminary diagnosis of tachyarrhythmia if it is determined that the preliminary diagnosis of tachyarrhythmia is proper according to the first measure of interval irregularity, and otherwise, inhibiting a final diagnosis of tachyarrhythmia, and, if a qualified preliminary diagnosis of tachyarrhythmia is made, then making a final diagnosis of tachyarrhythmia if the counted number of sinus intervals during the tachyarrhythmia detection period is less than a selected maximum sinus interval count, and otherwise, inhibiting a final diagnosis of tachyarrhythmia.
In an alternative embodiment which can be implemented with either of the above embodiments, the sinus interval history technique can be applied to just a rate overlap zone. Thus, after the initial diagnosis based on rate, the rate average is compared to a higher tachycardia threshold defining a rate overlap zone. If the average falls within the zone then the algorithm of the algorithm of the invention continues. If the average is greater than the rate overlap zone then a ventricular tachycardia is diagnosed.
The present invention also encompasses a cardiac therapy device, e.g., an implantable cardioverter-defibrillator (ICD), programmed to implement the tachyarrhythmia detection method of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
These and various other features and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a flow chart illustrating the detection method of the present invention used to provide a stand-alone measure of interval irregularity which enables discrimination between ventricular and supraventricular tachyarrhythmias;
FIG. 2 is a flow chart illustrating the detection method of the present invention used in conjunction with a conventional detection algorithm which provides a first measure of interval irregularity, to provide a second measure of interval irregularity which enables discrimination between ventricular and supraventricular tachyarrhythmias;
FIG. 3 is a diagram depicting an electrogram which exhibits a sinus rhythm which spontaneously converts to a monomorphic ventricular tachycardia (MVT), with the intervals between successive heartbeats which are binned as sinus intervals being designated "S" and the intervals between successive heartbeats which are binned as tachycardia intervals being designated "T"; and,
FIG. 4 is a diagram depicting an electrogram which exhibits an episode of atrial fibrillation, with the intervals between successive heartbeats which are binned as sinus intervals being designated "S" and the intervals between successive heartbeats which are binned as tachycardia intervals being designated "T".
DETAILED DESCRIPTION OF THE INVENTION
In overview, the present invention encompasses a novel detection algorithm which can be used in conjunction with a conventional diagnosis algorithm which can be used to provide a stand-alone measure of interval irregularity which enables discrimination between ventricular and supraventricular tachyarrhythmias (as is depicted in FIG. 1), or which provides a first measure of interval irregularity for qualifying a diagnosis of tachyarrhythmia, in order to provide a second measure of interval irregularity which enables discrimination between ventricular and supraventricular tachyarrhythmias (as is depicted in FIG. 2). For example, the novel detection algorithm of the present invention can be used to independently qualify a cardiac episode which has been preliminarily diagnosed as a tachyarrhythmia as being either a ventricular or supraventricular tachyarrhythmia; or, alteratively, the novel detection algorithm of the present invention can be used to further qualify a cardiac episode which has already been diagnosed (preliminarily) as a tachyarrhythmia (by a diagnosis algorithm) and which has already been qualified in accordance with a first measure of interval irregularity as being a regular tachyarrhythmia, as either a ventricular or supraventricular tachyarrhythmia.
The present invention is basically premised upon the fact that during an episode of ventricular tachycardia most, if not all, intervals between successive heartbeats are tachycardia (non-sinus) intervals, and that consequently, it is possible to inhibit a diagnosis of ventricular tachycardia by determining whether more than a selected small number of sinus intervals or sinus average intervals occur during a detection period (window) in which the conventional ventricular tachyarrhythmia diagnosis criteria are met.
At the outset, it should be clearly understood that the specific diagnosis algorithm used in conjunction with the detection algorithm of the present invention is not limiting to the present invention, i.e., any convenient diagnostic algorithm can be used. In general, the detection algorithm of the present invention is employed to qualify a preliminary diagnosis of ventricular tachyarrhythmia made in any suitable manner, in order to inhibit the diagnosis if a prescribed criterion (discussed hereinbelow) is satisfied. In this connection, for ease of illustration of the present invention, it will be assumed that the '058 diagnosis algorithm described hereinabove is employed in order to make a preliminary diagnosis of tachyarrhythmia, although this is obviously not limiting to the present invention, in its broadest aspect.
As was described previously, the '058 diagnostic algorithm classifies each interval between successive heartbeats according to the duration of the interval and the computed interval average (calculated using the most recent four (or other prescribed number) interval durations). A detection period (window) is started when a prescribed initial condition is met, namely, that the computed interval and interval average are in the tachyarrhythmia range. After the detection period is commenced, each subsequent interval is binned according to the duration of the interval and the computed interval average associated with the interval, i.e., the appropriate bin is incremented based upon the classification of the interval. The diagnostic algorithm terminates the detection period and makes a preliminary diagnosis when any of the bins is filled, the diagnosis being based upon which of the bins is filled first.
If the preliminary diagnosis is tachyarrhythmia, then the '058 detection algorithm qualifies the diagnosis (i.e., verifies the accuracy of the preliminary diagnosis) by using a measure of interval alternans, namely, the relative number of sinus intervals and tachyarrhythmia intervals, to discriminate a bigeminal rhythm from a tachyarrhythmia. In particular, if the number of tachycardia intervals counted during the detection period is not greater than the number of sinus intervals which were counted during the detection period by some prescribed value ("bigeminal avoidance criteria"), then the rhythm is considered a bigeminal rhythm. The detection algorithm may also determine whether the detected rhythm is regular or irregular (i.e., provides a "measure of interval irregularity"), e.g., by looking at beat-to-beat variations. If the rhythm is determined to satisfy either the bigeminal avoidance criteria or the measure of interval irregularity criterion (i.e., is determined to be irregular), a final diagnosis of tachyarrhythmia is inhibited.
In accordance with the detection method of the present invention, each interval is further classified as an absolute sinus interval if either the duration of that interval or the associated interval average is in the sinus range, e.g., greater than a prescribed sinus duration threshold. Further, the number of absolute sinus intervals are counted, with the count being initialized when the first tachyarrhythmia interval is binned (i.e., at the beginning of each detection period) and reset at the end of each detection period. If the number of absolute sinus intervals which are counted during the detection period (hereinafter referred to as the "sinus interval history" (SIH) count) is greater than a selected small number (e.g., 1-8), then the detected rhythm is considered to be a supraventricular arrhythmia, and a final diagnosis of tachyarrhythmia is inhibited. (If the detection method of the present invention is used in conjunction with a "first measure of interval irregularity", as opposed to being implemented as a stand-alone/independent measure of interval irregularity, then it must also be determined that the rhythm is regular in accordance with the "first measure of interval irregularity"). In this regard, any convenient hardware or software counter can be used to count the absolute sinus intervals, as will be readily apparent to those of ordinary skill in the pertinent art.
Thus, the detection method of the present invention can be used when a preliminary diagnosis of tachyarrhythmia is made in order to discriminate between ventricular and supraventricular tachyarrhythmia, and thereby prevent an improper diagnosis of tachyarrhythmia and delivery of therapy for tachyarrhythmia when such is not warranted. In this sense, the detection method of the present invention can be considered as providing a measure of interval irregularity (the SIH count) which can be used independently to qualify a diagnosis of tachyarrhythmia, or which can be used as an additional measure of interval irregularity to further qualify a diagnosis of tachyarrhythmia that has already been qualified as correct according a first measure of interval irregularity.
With reference now to FIG. 1, there can be seen a flow chart illustrating the detection method of the present invention used to provide a stand-alone measure of interval irregularity which enables discrimination between ventricular and supraventricular tachyarrhythmias. More particularly, a preliminary diagnosis of tachyarrhythmia is made, at step 20, (e.g., by a conventional diagnosis algorithm). The preliminary diagnosis of tachycardia may include a bigeminal avoidance step in accordance with the '058 detection algorithm. After preliminary diagnosis of tachycardia, the algorithm proceeds to step 22, in which it is determined whether the SIH count is below the selected SIH count threshold (e.g., 1-8). If yes, then the algorithm proceeds to step 24, and indicates that the tachyarrhythmia is ventricular in origin. If not, then the algorithm goes to step 26, and indicates that the tachyarrhythmia is supraventricular in origin. Thus, in this embodiment of the present invention, the SIH count is used as a stand-alone measure of interval irregularity in order to qualify the preliminary diagnosis of tachyarrhythmia, i.e., to confirm (verify) that a diagnosis of tachyarrhythmia is proper, or to determine that a diagnosis of tachyarrhythmia is improper.
With reference now to FIG. 2, there can be seen a flow chart illustrating the detection method of the present invention used in conjunction with a conventional diagnosis algorithm which provides both bigeminal avoidance and a first measure of interval irregularity. More particularly, after a preliminary diagnosis of tachyarrhythmia has been made, at step 40, (e.g., by a conventional diagnosis algorithm), the algorithm proceeds to step 42, in which it determines if the rhythm is a bigeminal rhythm as discussed in connection with the '058 detection algorithm. If it is determined that a bigeminal rhythm is present, diagnosis of a tachycardia is inhibited at step 44. If the rhythm is not bigeminal, the algorithm proceeds to step 46, in which it determines whether a first measure of interval irregularity indicates whether the preliminarily diagnosed tachyarrhythmia is "regular" (i.e., may be ventricular in origin) or is irregular (e.g., atrial fibrillation). If the preliminarily diagnosed tachyarrhythmia is determined to be "irregular" according to the first measure of interval irregularity, then the algorithm proceeds to step 48, and indicates that the tachyarrhythmia is supraventricular in origin. If the preliminarily diagnosed tachyarrhythmia is determined to be "regular" according to the first measure of interval irregularity, then, in accordance with the present invention, the algorithm proceeds to step 50, in which it is determined whether the SIH count is below the selected SIH count threshold (e.g., 1-8). If yes, then the algorithm proceeds to step 52, and indicates that the tachyarrhythmia is "regular", i.e., ventricular in origin. If not, then the algorithm goes to step 48, and indicates that the tachyarrhythmia is supraventricular in origin. Thus, in this embodiment of the present invention, the SIH count is used as a second measure of interval irregularity in order to further qualify the preliminary diagnosis of tachyarrhythmia, i.e., to confirm (verify) that a diagnosis of tachyarrhythmia is proper, or to determine that a diagnosis of tachyarrhythmia is improper. It should be noted that the embodiment of FIG. 2 can also be implemented without the bigeminal avoidance step 42.
In an alternative embodiment which can be used with the embodiment of either FIG. 1 or FIG. 2, the SIH test is applied only if the tachyarrhythmia falls within a rate overlap zone. Thus, if the average associated with the last tachyarrhythm is interval is shorter than a rate overlap threshold and thus falls outside the rate overlap zone, a final diagnosis of a tachyarrhythmia of ventricular origin is given. However, if the average duration is greater than the rate overlap threshold and shorter than the tachyarrhythmia threshold, then the SIH count is used to provide a final diagnosis in accordance with the description above.
With reference now to FIGS. 3 and 4, the operation of the detection method of the present invention with respect to two different cases will now be described (it first will be assumed that the stand-alone embodiment of the detection method of the present invention is employed). For ease of illustration it will be assumed that the '058 diagnostic algorithm is used in both cases. With particular reference now to FIG. 3, there can be seen an electrogram which exhibits a sinus rhythm which spontaneously converts to a monomorphic ventricular tachycardia (MVT), with the intervals between successive heartbeats which are binned as sinus intervals being designated "S" and the intervals between successive heartbeats which are binned as tachycardia intervals being designated "T".
As can be seen in FIG. 3, after four intervals whose duration and associated interval average fall within the sinus zone, and which are thus binned as sinus intervals ("S"), the rhythm spontaneously converts to a monomorphic ventricular tachyarrhythmia (MVT). During the first three intervals following the commencement of the tachyarrhythmia, the interval duration falls within the tachycardia zone, but the interval average remains within the sinus zone, and thus, none of these intervals are binned as tachycardia intervals. By the fourth interval following the commencement of the tachyarrhythmia, the interval average has reached the tachycardia zone, and the subsequent intervals that have a duration which falls within the tachycardia zone are binned as tachycardia intervals ("T"). It will be assumed that eight consecutive tachycardia intervals ("T") satisfy the criterion for tachyarrhythmia detection. Thus, after eight consecutive T intervals, a preliminary diagnosis of tachyarrhythmia is made, as indicated by the downwardly pointing arrow in FIG. 3. This step can further include application of the bigeminal avoidance criterion.
In accordance with the present invention, the SIH count is reset (initialized to zero) when the first interval (T) which is binned as a tachycardia interval occurs. Thereafter, until the preliminary diagnosis of tachyarrhythmia is made (at which time the detection period is terminated), the number of absolute sinus intervals is counted in the manner described hereinbefore. More particularly, all intervals whose duration or associated interval average falls within the sinus zone are classified as absolute sinus intervals (AS). In the case of the cardiac episode (MVT) depicted in FIG. 3, since all intervals which occur during the detection period are binned as tachycardia intervals T, (i.e., eight consecutive T intervals occur), the SIH count is not incremented, and thus, is zero (0) at the time the preliminary diagnosis is made. Thus, in accordance with the present invention, it will be determined that the SIH count is below the selected maximum SIH count threshold (e.g., 2), and the preliminary diagnosis of tachyarrhythmia will be verified as proper, a final diagnosis of tachyarrhythmia made. Of course, the appropriate therapy will be delivered in the normal manner to terminate the diagnosed tachyarrhythmia, as seen in FIG. 3 with the delivery of antitachycardia pacing therapy.
The outcome would be unchanged if a preliminary interval irregularity step (as shown in FIG. 2) were applied to the rhythm of FIG. 3. In that case, for example, the duration of a prescribed number of intervals during the tahcyarrhythmia detection period preceding the preliminary diagnosis of tachyarrhythmia detection are considered. The longest and shortest of these intervals are discarded, the difference between the duration of the second longest and second shortest is calculated and this difference is compared to a selected delta. If the difference is greater than or equal to the delta, the rhythm is considered irregular. If the difference is shorter than the delta, the rhythm is considered regular. In FIG. 3, if the prescribed number of intervals is for example 8, it can be easily seen that the difference between the second longest and second shortest interval would be less than a typical selected delta and the preliminary interval irregularity measure would indicate that the rhythm would be considered regular. Examination of the second measure of interval irregularity, SIH, would confirm the rhythm as regular. It should be noted that other interval irregularity or rate stability tests known in the art could be used.
With particular reference now to FIG. 4, there can be seen an electrogram which exhibits an episode of atrial fibrillation (AF), which is a type of supraventricular tachyarrhythmia. Again, the intervals which are binned as sinus intervals are designated "S", the intervals which are binned as tachycardia intervals are designated "T", and the intervals which are classified as absolute sinus intervals are designated "AS". As can be seen in FIG. 4, three consecutive intervals T which are binned as tachycardia intervals are followed by two intervals which have a duration which falls within the sinus zone but which are not binned as either sinus or tachycardia intervals, which two intervals are in turn followed by two intervals S which are binned as sinus intervals. The two binned sinus intervals S are then followed by three consecutive intervals which have a duration which falls within the tachycardia zone, but which are not binned as tachycardia intervals, since the associated interval averages fall in the sinus zone. These three unbinned intervals are followed by nine (9) consecutive intervals which are binned as tachycardia intervals T.
It will be assumed that a total of twelve tachycardia intervals ("T") satisfy the criterion for tachyarrhythm is detection, and that a total of three sinus intervals ("S") satisfy the criterion for sinus rhythm detection. Thus, after twelve T intervals, a preliminary diagnosis of tachyarrhythmia is made, as indicated by the downwardly pointing arrow in FIG. 4, since the tachyarrhythmia detection criterion is met before the sinus rhythm detection criterion is met, i.e., the tachyarrhythmia bin is filled before the sinus bin is filled.
In accordance with the present invention, the SIH count is reset (initialized to zero) when the first interval (T) which is binned as a tachycardia interval occurs. Thereafter, until the preliminary diagnosis of tachyarrhythmia is made (at which time the detection period is terminated), the number of absolute sinus intervals is counted in the manner described hereinbefore. More particularly, all intervals whose duration or associated interval average falls within the sinus zone are classified as absolute sinus intervals "AS". In the case of the cardiac event (AF) depicted in FIG. 4, a total of seven (7) intervals are classified as absolute sinus intervals AS. Thus, in accordance with the present invention, it will be determined that the SIH count is above the selected maximum SIH count threshold (e.g., 2), and the preliminary diagnosis of tachyarrhythmia will not be verified as proper, i.e., the tachyarrhythmia will be identified as non-ventricular in origin, and a diagnosis of tachyarrhythmia will be inhibited. Thus, no therapy will be delivered.
It should be noted that presently available measures of interval irregularity would not enable the atrial fibrillation to be identified as supraventricular in origin in the above-described case depicted in FIG. 4, since the atrial fibrillation rhythm had stable intervals according to more typical measures of irregularity during the detection window. Thus, using presently available detection algorithms, an improper final diagnosis of tachyarrhythmia would have been returned in this case.
With continuing reference to FIGS. 3 and 4, the operation of the detection method of the present invention with respect to the two different cases will now be described for the embodiment of the detection method utilizing a preliminary interval irregularity measure followed by the SIH measure. It will be assumed that the '058 diagnostic algorithm is used in both cases as discussed above with reference to the stand-alone embodiment. With particular reference now to FIG. 3, there can be seen an electrogram which exhibits a sinus rhythm which spontaneously converts to a monomorphic ventricular tachycardia (MVT), with the intervals between successive heartbeats which are binned as sinus intervals being designated "S" and the intervals between successive heartbeats which are binned as tachycardia intervals being designated "T".
As can be seen in FIG. 3, after four intervals whose duration and associated interval average fall within the sinus zone, and which are thus binned as sinus intervals ("S"), the rhythm spontaneously converts to a monomorphic ventricular tachyarrhythmia (MVT). After eight consecutive T intervals, a preliminary diagnosis of tachyarrhythmia is made, as indicated by the downwardly pointing arrow in FIG. 3. A bigeminal avoidance criterion is applied but since there were no sinus intervals detected after initiation of the tachycardia detection period the rhythm is not bigeminal. Next, the preliminary interval irregularity criterion is applied. As discussed above, this can be any of the interval irregularity tests known in the art and the particular test is not part of the present invention. Using the technique described hereinabove, a window of the 8 intervals preceding the preliminary tachyarrhythmia diagnosis is considered and the difference between the second longest and second shortest of these intervals is compared with the selected delta. The test indicates a regular rhythm.
The SIH count is reset (initialized to zero) when the first interval (T) which is binned as a tachycardia interval occurs. Thereafter, until the preliminary diagnosis of tachyarrhythmia is made (at which time the detection period is terminated), the number of absolute sinus intervals is counted in the manner described hereinbefore. Since, in FIG. 3, all intervals which occur during the detection period are binned as tachycardia intervals T, (i.e., eight consecutive T intervals occur), the SIH count is not incremented, and thus, is zero (0) following the preliminary diagnosis, bigeminal avoidance test and the preliminary interval irregularity determination. Thus, in accordance with the present invention, it will be determined that the SIH count is below the selected maximum SIH count threshold (e.g., 2), and the preliminary diagnosis of tachyarrhythmia will be verified as proper, a final diagnosis of tachyarrhythmia made.
With particular reference now to FIG. 4, there can be seen an electrogram which exhibits an episode of atrial fibrillation (AF), which is a type of supraventricular tachyarrhythmia. Again, the intervals which are binned as sinus intervals are designated "S", the intervals which are binned as tachycardia intervals are designated "T", and the intervals which are classified as absolute sinus intervals are designated "AS". As can be seen in FIG. 4, three consecutive intervals T which are binned as tachycardia intervals are followed by two intervals which have a duration which falls within the sinus zone but which are not binned as either sinus or tachycardia intervals, which two intervals are in turn followed by two intervals S which are binned as sinus intervals. The two binned sinus intervals S are then followed by three consecutive intervals which have a duration which falls within the tachycardia zone, but which are not binned as tachycardia intervals, since the associated interval averages fall in the sinus zone. These three unbinned intervals are followed by nine (9) consecutive intervals which are binned as tachycardia intervals T.
It will be assumed that a total of twelve tachycardia intervals ("T") satisfy the criterion for tachyarrhythmia detection, and that a total of three sinus intervals ("S") satisfy the criterion for sinus rhythm detection. Thus, after twelve T intervals, a preliminary diagnosis of tachyarrhythmia is made, as indicated by the downwardly pointing arrow in FIG. 4, since the tachyarrhythmia detection criterion is met before the sinus rhythm detection criterion is met, i.e., the tachyarrhythmia bin is filled before the sinus bin is filled.
In accordance with the second embodiment of the present invention, the bigeminal avoidance test is applied and determines that the rhythm is not bigeminal since the number of sinus intervals does not equal the number of tachyarrhythmia intervals. Next the preliminary interval irregularity test is applied. Whether this test indicates a regular rhythm or not is a function of the particular test applied and its programmed sensitivity. For purposes of illustration, we will use 12 intervals for the window and a delta of 50 reset. The difference between the second longest and second shortest of the 12 intervals preceding the preliminary tahcyarrhythmia diagnosis is compared with the selected delta. The difference is smaller than the delta and the preliminary interval irregularity test determines a regular interval. The SIH count is reset (initialized to zero) when the first interval (T) which is binned as a tachycardia interval occurs. Thereafter, until the preliminary diagnosis of tachyarrhythmia is made (at which time the detection period is terminated), the number of absolute sinus intervals is counted in the manner described hereinbefore. More particularly, all intervals whose duration or associated interval average falls within the sinus zone are classified as absolute sinus intervals "AS". In the case of the cardiac event (AF) depicted in FIG. 4, a total of seven (7) intervals are classified as absolute sinus intervals AS. Thus, in accordance with the present invention, it will be determined that the SIH count is above the selected maximum SIH count threshold (e.g., 2), and the preliminary diagnosis of tachyarrhythmia and preliminary interval irregularity tests will not be verified as proper, i.e., the tachyarrhythmia will be identified as non-ventricular in origin, and a diagnosis of tachyarrhythmia will be inhibited. Thus, no therapy will be delivered.
It will be readily appreciated by those skilled in the pertinent art that the present invention also encompasses a cardiac therapy device, e.g., an ICD, programmed to implement the tachyarrhythmia detection method of the present invention. In this regard, it is a routine matter to those of ordinary skill in the pertinent art to write the code constituting the software (computer program) for programming the ICD (or other cardiac therapy device), using readily available programming tools. Further, although the detection algorithm has been described hereinabove in terms of sensing intervals between successive heartbeats, it should be clearly understood that the term "heartbeats" is intended in a generic sense to mean "cardiac events", e.g., QRS complexes. Additionally, the particular hardware and/or software used to count or bin intervals that are "countable" or "binnable" in accordance with the detection algorithm employed, and/or to count absolute sinus intervals to generate the SIH count, is not limiting to the present invention, as will be readily apparent to those of ordinary skill in the pertinent art.
Although the present invention has been described in detail hereinabove, it should be clearly understood that many variations and/or modifications of the basic inventive concepts herein taught which may appear to those skilled in the pertinent art will still fall within the spirit and scope of the present invention, as defined in the appended claims.
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A method for detecting cardiac arrhythmias which includes the steps of detecting a patient's cardiac activity, counting the number of intervals which satisfy a first selected criterion, and producing a sinus interval history count indicative of the number of such intervals which are counted, making a preliminary diagnosis of tachyarrhythmia upon detecting that the cardiac activity satisfies a second selected criterion, and, making a final diagnosis of tachyarrhythmia if the sinus interval history count is less than a selected maximum sinus interval history count, and otherwise, inhibiting a final diagnosis of tachyarrhythmia. In an alternative embodiment, the method for detecting cardiac arrhythmias includes the steps of detecting a patient's cardiac activity, counting the number of intervals which satisfy a first selected criterion, and producing a sinus interval history count indicative of the number of such intervals which are counted, making a preliminary diagnosis of tachyarrhythmia upon detecting that the cardiac activity satisfies a second selected criterion, determining if the preliminary diagnosis of tachyarrhythmia is proper according to a first measure of interval irregularity, making a qualified preliminary diagnosis of tachyarrhythmia if it is determined that the preliminary diagnosis of tachyarrhythmia is proper according to the first measure of interval irregularity, and otherwise, inhibiting a final diagnosis of tachyarrhythmia, and, if a qualified preliminary diagnosis of tachyarrhythmia is made, then making a final diagnosis of tachyarrhythmia if the sinus interval history count is less than a selected maximum sinus interval history count, and otherwise, inhibiting a final diagnosis of tachyarrhythmia. The invention also includes a cardiac therapy device, e.g., an implantable cardioverter-defibrillator (ICD), programmed to implement the tachyarrhythmia detection method of the present invention.
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BACKGROUND OF THE INVENTION
The field of the present invention is anti-lock brake systems for motorcycles.
Anti-lock braking systems for the front wheel of a motorcycle have been developed which include a master cylinder which may be actuated by the operator, a front wheel brake operated by the master cylinder through a brake line therebetween and an anti-lock control unit interposed in the brake line between the master cylinder and the front wheel brake. The anti-lock control unit is adapted to sense the nearly-locked condition of a front wheel and shut off the hydraulic pressure to the brake itself. One such braking system is disclosed in Japanese Patent Laid-open Publication No. 120440/1981.
With the motorcycle provided with such an anti-lock braking system, the chassis may vibrate when the front wheel brake is applied. This vibration occurs in a vertical direction with the repeated operation of an anti-lock control unit which rapidly cycles the brake on and off under conditions of approaching wheel lock. The problem is aggregated with motorcycles having high centers of gravity and short wheel bases.
The reaction of the front fork responsive to the action of braking and of the anti-lock braking device is to begin to dive. As the dive commences, a short period of time exists where there is no increase of the front wheel load on the tire contact with the ground. Consequently, there is no increase in the resistance to locking of the brake during that short period. Consequently, a slight decrease in braking efficiency could theoretically be experienced.
SUMMARY OF THE INVENTION
The present invention is directed to an anti-lock braking system employing an anti-dive device with a damped telescopic front suspension. The anti-dive device is responsive to the brake force applied to the front wheel. The cooperation may be achieved by tapping hydraulic pressure downstream of the anti-lock control unit or by sensing and applying the actual reaction to braking force of the front wheel.
Accordingly, it is an object of the present invention to provide an anti-lock brake system having anti-dive characteristics. Other and further objects and advantages will appear hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1-7 illustrate a first embodiment of the present invention, wherein:
FIG. 1 is a schematic plan of a motorcycle provided with an anti-lock braking system on a front wheel;
FIG. 2 is a sectioned side elevation of a principal portion of the anti-lock braking system;
FIGS. 3 and 4 are sectional views taken along the lines III--III and IV--IV, respectively, in FIG. 2;
FIG. 5 is an enlarged sectional view taken along the line V--V in FIG. 4;
FIG. 6 is a wiring diagram of a display circuit in FIG. 2; and
FIG. 7 is a side elevation of the anti-lock braking system with a front fork shown in section.
FIG. 8 is a side elevation similar to FIG. 7, showing a second embodiment of the present invention; and
FIG. 9 is a graph showing the relation between the time and the angular velocity characteristics during the anti-lock controlling of a front wheel brake, wherein a curve a indicates the characteristics of a prior art anti-lock braking system of this kind; and a curve b the characteristics of the anti-lock braking system according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The embodiments of the present invention will now be described.
First, referring to FIG. 1 which shows a first embodiment of the present invention, a motorcycle 1 is provided with left and right front wheel brakes 3f, 3f for braking a front wheel 2f, and first and second rear wheel brakes 3r 1 , 3r 2 for braking a rear wheel 2r. Both of the front wheel brakes 3f, 3f and the first rear wheel brake 3r 1 are operated by an output hydraulic pressure from a front master cylinder 5f which is operated by a brake lever 4, and the second rear wheel brake 2r by an output hydraulic pressure from a rear master cylinder 5r which is operated by a brake pedal 6. Especially, the hydraulic braking pressure for the front wheel brakes 3f, 3f is controlled by an anti-lock control unit 7.
Referring to FIGS. 2 and 3, a hub 8 of the front wheel 2f is supported via bearings 11, 11 on an axle 10 which is supported at its both ends on the lower ends of left and right telescopic fork members 9l, 9r constituting a front fork 9. Each of the two front wheel brakes 3f, 3f, which are provided on both sides of the front wheel 2f, consists of a brake disc 12 attached to an end surface of the hub 8, and brake caliper 14 supported on the front fork 9 via a bracket 13 in such a manner that the brake caliper 14 straddle the brake disc 12. The brake caliper 14 is adapted to be operated when an output hydraulic pressure is supplied from the master cylinder 5f into an input port 14a thereof, thereby being rendered capable of holding the brake disc 12 firmly from both sides thereof to apply braking force to the front wheel 2f.
The anti-lock control unit 7 is provided in a hydraulic pipe 15 by which an output port 5fa of the front master cylinder 5f and the input port 14a of each of the brake calipers 14 are connected.
The anti-lock control unit 7 consists mainly of a hydraulic pump 16 adapted to be driven by the front wheel 2f when braking, a modulator 17 having a hydraulic control chamber 18, into which the discharge pressure from the hydraulic pump 16 is introduced, and provided in an intermediate portion of the hydraulic pipe 15, a normally-closed pressure discharge valve 20 provided in a communication passage between the hydraulic control chamber 18 and an oil tank 19, and an inertial sensor 21 adapted to detect the nearly-locked condition of the front wheel 2f and open the pressure discharge valve 20. These main constituent parts are arranged in a casing 22.
The casing 22 is formed of a cup-shaped case member 22a, and a cover member 22b fitted into an open end of the case member 22a and fixed thereto with screws 23. The case member 22a is provided so that it is held in a recess 8a formed in one end surface of the hub 8. The cover member 22b is supported on the axle 10 via a hollow shaft 24 provided fixedly in the central portion thereof, and joined to the front fork 9 via a rotation-preventing means so that the case member 22b does not turn around the axle 10. The rotation-preventing means may consist of an arbitrarily-selected part; it suitably consists, for example, of the bolts 25 (refer to FIG. 2) by which the bracket 13 is secured to the front fork 9.
The hydraulic pump 16 consists of a cam shaft 26 provided in parallel with the axle 10, a push rod 27 provided so as to oppose its inner end to an eccentric cam 26a formed on the cam shaft 26, a pump piston 28 contacting the outer end of the push rod 27, an operating piston 29 contacting the outer end of the pump piston 28, and a return spring 30 urging the push rod 27 in the direction in which the push rod 27 is apart from the eccentric cam 26a.
The push rod 27 and pump piston 28 are fitted slidably in a first cylindrical bore 33 formed in the cover member 22b, so as to define an inlet chamber 31 and an outlet chamber 32 on the outer side of the outer circumferential surfaces thereof, respectively. A plug 34 is fitted fixedly into the outer end portion of the first cylindrical bore 33 so that a pump chamber 35 is defined between the plug 34 and pump piston 28. The operating piston 29 is fitted slidably in the plug 34 so as to define a hydraulic chamber 36 therein.
The inlet chamber 31 is communicated with the oil tank 19 via a pipe 37, and with the pump chamber 35 via a suction valve 38, the pump chamber 35 being communicated with the outlet chamber 32 via a one-way seal member 39 having the function of a discharge valve. The hydraulic chamber 36 is connected to an upstream member 15a of the hydraulic pipe 15 so as to be communicated constantly with an output port 5fa in the front master cylinder 5f.
As shown in FIG. 4, the cam shaft 26 is supported on the cover member 22b via bearings 40, 40', and adapted to be driven via a pair of gears 43, 44 by a driving shaft 42 which is supported rotatably on the hollow shaft 24 via bearings 41, 41. The driving shaft 42 is adapted to be driven by the front wheel 2f via a speedup gear 45, which will be described later.
A meter driving gear 49 is mounted fixedly on an outer end portion, which is on the opposite side of the gear 44, of the cam shaft 26, and meshed with a driven gear 50 which is connected to an input shaft of a speedometer 51 on the motorcycle.
The modulator 17 consists of a pressure reduction piston 46, a fixed piston 47 receiving one end of the reduction piston 46 to limit the backward movement thereof, and a return spring 48 urging the piston 46 in the direction in which the piston 46 engages with the fixed piston 47. Both of these pistons 46, 47 are fitted slidably in a second cylindrical bore 52 which is formed in the cover member 22b so that the second cylindrical bore 52 is adjacent to the first cylindrical bore 33.
In the second cylindrical bore 52, the reduction piston 46 defines a hydraulic control chamber 18 between itself and the inner end wall of the bore 52, and a hydraulic output chamber 55 between itself and the fixed piston 47. The fixed piston 47 defines a hydraulic input chamber 54 on the outer side of the outer circumferential surface thereof. This hydraulic chamber 54 communicates with the chamber 36 in the hydraulic pump 16 via an oil passage 56. The hydraulic output chamber 55 is connected to a downstream pipe 15b of the hydraulic pipe 15 so as to be communicated constantly with the input ports 14a of the front wheel brakes 3f, 3f. The hydraulic control chamber 18 is communicated with the outlet chamber 32 in the hydraulic pump 16 via an oil passage 57.
The fixed piston 47 is provided with a valve chamber 58 communicated constantly with the hydraulic input chamber 54, and a valve port 59 by which the valve chamber 58 is communicated with the hydraulic output chamber 55. The valve chamber 58 is provided therein with a valve body 60 capable of opening and closing the valve port 59, and a valve spring 61 urging the valve body 60 toward the closed position. A valve rod 62 for opening the valve body 60 projects from one end surface of the reduction piston 46. This valve rod 62 keeps the valve body 60 open when the reduction piston 46 is in a limit position of the backward movement thereof.
The outer, open portion of the second cylindrical bore 52 is closed by an end plate 63 fixed to the cover member 22b. The fixed piston 47 is kept constantly in engagement with the end plate 63, because of the resilient force of the return spring 48 or the hydraulic pressure introduced into the hydraulic input and output chambers 54, 55.
The hydraulic pump 16 and modulator 17 are disposed on the rear side of the front fork 9 in the same manner as the brake caliper 14.
The pressure discharge valve 20 consists of a valve seat member 65 fitted firmly in a stepped cylindrical bore 64 in the cover member 22b, and a valve body 67 fitted slidably in the valve seat member 65 so as to open and close a valve port 66 thereof. The valve seat member 65 defines an inlet chamber 68 in a smaller-diameter portion of the stepped cylindrical bore 64, and an outlet chamber 69 in a larger-diameter portion thereof, these chambers 68, 69 being communicated with each other via the valve port 66. The inlet chamber 68 is in communication with the hydraulic control chamber 18 in the modulator 17 via the oil passage 20. The outlet chamber 69 is in communication with the inlet chamber 31 in the hydraulic pump 16 via an oil passage 71. Consequently, the outlet chamber 69 is in communication with the oil tank 19.
The sensor 21 consists of a speedup gear 45 into which power is input from the front wheel 2f, a flywheel 72 adapted to be rotated by the speedup gear 45, a cam means 73 for converting overrun rotation of the flywheel 72 into axial displacement, and an output lever means 74 capable of operating the pressure discharge valve 20 in accordance with the axial displacement of the flywheel 72. The speedup gear 45 is provided on the outer side of a rear wall of the case member 22a. The cam means 73, flywheel 72 and output lever means 74 are on the inner side of the case member 22a.
The speedup gear 45 has a planetary gear construction, and consists of a ring gear 76, which is pline-fitted on the inner circumferential surface of an annular support portion 75 projecting from the outer surface of the rear wall of the case member 22a, a plurality of planetary gears 78 supported rotatably 77 on the hub 8 and meshed with the ring gear 76, and a sun gear 79 formed at one end portion of the driving shaft 42 and meshed with the planetary gears 78.
A seal member 80 is inserted between the rear wall of the case member 22a and the driving shaft 42 extending therethrough. A seal member 81 is also inserted between the annular support portion 75 of the case member 22a and the hub 8.
In order to prevent the rotation of the front wheel 2f from being hindered if an overload is applied to the driving shaft 42, at least one of the constituent gears of the speedup gear 45, for example, the planetary gear 78, is made of a synthetic resin having a safety function like that of a fuse in that it breaks when torque on that gear exceeds a predetermined level.
The speedometer 51 is operatively connected to the driving shaft 42 which is driven by the speedup gear 45. Accordingly, if the gear 78 which is made of a synthetic resin should be broken, the speedometer stops operating in spite of the rotation of the front wheel 2f, so that the rider can therefore learn the occurrence of this accident.
The cam means 73 consists, as shown in FIG. 5, of a driving cam plate 82 fixed to the driving shaft 42, a driven cam plate 83 provided in opposition to the driving cam plate 82 so that the driven cam plate 83 can be rotated relatively thereto, and a thrust ball 84 engaged with cam recesses 82a, 83a in the opposite surfaces of the cam plates 82, 83. The cam recess 82a in the driving cam plate 82 is inclined so that the bottom surface of the recess 82a is shallower in the rotational direction 85 of the driving shaft 42. The cam recess 83a in the driven cam plate 83 is inclined so that the bottom surface of the recess 83a is deeper in the rotational direction 85 mentioned above. Accordingly, in a normal case where the driving cam plate 82 takes the driving position with respect to the driven cam plate 83, the thrust ball 84 engages the deepest portions of the cam recesses 82a, 83a, and the rotary torque received by the driving cam plate 82 from the driving shaft 42 is simply transmitted to the driven cam plate 83, so that the relative rotation of the cam plates 82, 83 does not occur. When the position of the driving cam plate 82 is reversed, i.e., when the driven cam plate 83 overruns the driving cam plate 82, the cam plates 82, 83 rotate relatively to each other. Consequently, the thrust ball 84 rolls in a climbing manner on the inclined bottom surfaces of the cam recesses 82a, 83a to apply thrust to these cam plates 82, 83 and cause the driven cam plate 83 to be displaced axially, i.e., in the direction in which the driven cam plate 83 is removed from the driving cam plate 82.
In order to lessen the impact occurring when the thrust ball 84 suddenly reaches the rolling limit in the cam recesses 82a, 83a, at least one of the constituent elements of the cam means 73 is made of a synthetic resin. In the illustrated embodiment, the driven cam plate 83 and the thrust ball 84 are made of a synthetic resin. This prevents vibration of the cam means 73, which is caused by such an impact, thereby proving the durability thereof.
The flywheel 72 is supported rotatably and slidably at its boss 72a on the driving shaft 42 via a bushing 86. The driven cam plate 83 is supported rotatably on the boss 72a, and engages one side surface of the flywheel 72 via a friction clutch plate 87. A pressure plate 89 is provided on the other side surface of the flywheel 72 via a thrust bearing 88.
The output lever means 74 has a support shaft 90 projecting from the portion of the inner surface of the cover member 22b which is between the axle 10 and pressure discharge valve 20, and a lever 91 supported on a neck portion 90a of a free end section of the support shaft 90 so that the lever 91 can be moved pivotally in the axial direction of the axle 10. A clearance 92 of a predetermined width extending in the pivoting direction of the lever 91 is provided between the neck portion 90a and lever 91. The lever 91 consists of a first longer arm 91a extending from the support shaft 90 to extend around the driving shaft 42, and a second shorter arm extending toward the pressure discharge valve 20. The first arm 91a is provided at an intermediate point with a contact portion 93 to engage the outer surface of the pressure plate 89. The contact portion 93 has a rounded projection toward the outer surface of the pressure plate.
A spring 94 is provided between a free end portion of the first arm 91 and the cover member 22b. A free end portion of the second arm 91b engages the outer end of the valve body 67 in the pressure discharge valve 20.
The resilient force of the spring 94 is applied to the lever 91 to press the contacting portion 93 of the first arm 91a against the pressure plate 89, and normally serves to press the valve body 67 in the pressure discharge valve 20 to thereby keep the valve 20 closed. The pressure received by the pressure plate 89 from the spring 94 generates the frictional locking force in three parts, i.e. the flywheel 72, friction clutch plate 87 and driven cam plate 83, and such force in the two cam plates 82, 83 that causes them to move toward each other.
When rotary torque which exceeds a predetermined value is applied between the driven cam plate 83 and flywheel 72, the above-mentioned frictional locking force is set so that slip occurs on the friction clutch plate 87.
A detecting unit 95 for detecting normal operation of the output lever means 74 is connected thereto. This detecting unit 95 consists of a switch holder 96 held firmly in the cover member 22b and projecting into a coiled portion of the spring 94, a lead switch 97 supported on the switch holder 96 in the coiled portion of the spring 94, and a permanent magnet 98 attached to the first arm 91a so as to be opposed to the lead switch 97. When the first arm 91a is turned at a predetermined angle toward the cover member 22b, the permanent magnet 98 is displaced to a position in which the lead switch 97 is closed.
A display circuit 99 is connected to the lead switch 97. The display circuit 99 is formed as shown in FIG. 6. When a main switch 100 is closed, an electric current flows from a power source 101 to the base of a transistor 104 through the main switch 100 and resistors 102, 103, so that the transistor 104 is turned on. Consequently, a display lamp 105 is turned on through the main switch 100 and kept lit. When the permanent magnet 98 is then displaced to the lead switch 97 to close the same, an electric current flows to the gate of a thyrister 106 through the lead switch 97. As a result, the thyrister 106 is turned on, and the electric current passing through the resistor 102 flows to the thyrister 106, so that the transistor 104 is turned off with the display lamp 105 then turned off. Accordingly, it can be detected by the interruption of the ON-state of this display lamp 105 that the lever 91 has been turned to the side of the cover member 22b against the resilient force of the spring 94. Even when the lever 91 is then returned to its original position to open the lead switch 97, the OFF-state of the display lamp 105 is retained by the thyrister 106 until the main switch 100 has been opened and then closed again.
An ignition switch or a braking switch for a motorcycle can be used as the main switch.
Returning to FIG. 1 again, an interconnecting pipe 110 branching from the intermediate portion, which is between the front master cylinder 5f and anti-lock control unit 7, of the hydraulic pipe 15, i.e. the upstream pipe 15a is connected to the input port of the first rear wheel brake Br 1 , and a proportional reducing valve 111 is provided in the intermediate portion of the interconnecting pipe 110. This proportional reductive valve 111 is a valve known in the art which is adapted to reduce the hydraulic output pressure from the front master cylinder 5f when this pressure has exceeded a predetermined level, and to transmit the resultant hydraulic pressure to the first rear wheel brake 2r 1 .
A hydraulic pipe 112, which extends from the output port of the rear master cylinder 5r, is connected to the input port of the second rear wheel brake Br 2 . Accordingly, the second rear wheel brake Br 2 is operated only when the rear master cylinder 5r is actuated.
While the vehicle runs, the driving shaft 42 is driven at an increased speed due to the rotational force transmitted from the front wheel 2f thereto via the speedup gear 45, and the flywheel 72 is then driven via the cam means 73 and friction clutch plate 87, so that the flywheel 72 is rotated at a higher speed than the front wheel 2f. Therefore, the flywheel 72 has a large rotary inertial force.
At the same time that the flywheel is rotated, the cam shaft 26 and speedometer 51 are also driven by the driving shaft 42.
When the front master cylinder 5f is operated so as to brake the vehicle, the hydraulic output pressure therefrom is transmitted to the front wheel brakes 3f, 3f via the upstream pipe 15a of the hydraulic pipe 15, hydraulic chamber 36 in the hydraulic pump 16, hydraulic input chamber 54 in the modulator 17, valve chamber 58, valve port 59, hydraulic output chamber 55, and downstream pipe 15b of the hydraulic pipe 15 in the mentioned order. This hydraulic output pressure is also transmitted to the first rear wheel brake Br 1 via the upstream pipe 15a and interconnecting pipe 110. The front and rear wheel brakes 3f, 3f, Br 1 can thus be operated to apply braking force to the front and rear wheels 2f, 2r at once.
In the hydraulic pump 16, the hydraulic output pressure from the front master cylinder 5f is introduced into the hydraulic chamber 36. Consequently, the pump piston 28 is moved reciprocatingly due to the pressing effect of the hydraulic pressure on the operating piston 29 and the lifting effect of the eccentric cam 26a on the push rod 27. In a suction stroke in which the pump piston 28 is moved toward the push rod 27, the suction valve 38 is opened, and the oil in the oil tank 19 is sucked from the pipe 35 into the pump chamber 35 via the inlet chamber 31. In an exhaust stroke in which the pump piston 28 is moved toward the operating piston 29, the one-way seal member 39 makes a valve-opening action to cause the oil in the pump chamber 35 to flow under pressure into the output chamber 32 and then into the hydraulic control chamber in the modulator 17 via the oil passage 57. When the pressures in the output chamber 32 and hydraulic control chamber 18 have increased to a predetermined level, the pump piston 28 is held in the position, in which the pump piston 28 is engaged with the plug 34, due to the pressure in the output chamber 32.
The communication between the hydraulic control chamber 18 in the modulator 17 and the oil tank 19 is initially cut off since the pressure discharge valve 20 is closed. Accordingly, the hydraulic pressure supplied from the hydraulic pump 16 to the hydraulic control chamber 18 is applied directly to the reduction piston 46 to hold the piston 46 in the position in which the backward movement thereof is limited, and the valve body 60 is kept open by the valve rod 62 to thereby permit the passage of the hydraulic output pressure from the front master cylinder 5f.
Therefore, in the initial stage of a braking operation, the level of the braking force applied to the front wheel brakes 3f, 3f varies in proportion to that of the hydraulic output pressure from the front master cylinder 5f.
When angular deceleration occurs in the front wheel 2f during this braking operation, the flywheel 72, which senses this phenomenon, is formed to make an overrunning rotation with respect to the driving shaft 42 due to the inertial force thereof. During this time, the moment of rotation of the flywheel 72 causes the two cam plates 82, 83 to be turned relatively to each other, and the thrust occurring due to the rolling of the thrust ball 84 causes the flywheel 72 to be displaced axially, and the pressure plate 89 to press the lever 91.
The movement of the lever 91 being pressed by the pressure plate 89 will now be discussed. Since the clearance 92 exists between the support shaft 90 and lever 91, the lever is supported initially at three points, i.e., on the spring 94, pressure plate 89 and pressure discharge valve 20. When the lever 91 is pressed by the pressure plate 89, it is turned about the valve body 67 as a fulcrum. When this pivotal movement of the lever 91 has progressed to the extent that the lever 91 has attained a predetermined angle, the clearance 92 between the support shaft 90 and lever 91 is lost, and the fulcrum on the side of the second arm 91b is moved from the valve body 67 to the support shaft 90 which is closer to the contacting portion 93. As a result, the lever 91 is then turned about the support shaft 90 as a fulcrum.
The lever ratio at which the lever 91 is turned by the pressure plate 89 thus varies in two steps. Therefore, even if the resilient force of the spring 94 is constant, the lever 91 is turned initially by a comparatively low pressure from the pressure plate 89. After the fulcrum of the lever 91 with respect to the pivotal movement thereof has been moved, the lever is not turned unless the pressure from the pressure plate 89 is increased to a predetermined level. Accordingly, the lever 91 is turned by the pressure from the pressure plate 89 in the stage of a braking operation in which the angular deceleration occurring in the front wheel 2f is comparatively small, to cause the permanent magnet 98 to be moved to a position close to the closing position of the lead switch 37. Consequently, the display circuit 99 is actuated in the previously-described manner, so that the rider can ascertain that the sensor 21 is normally operated.
When the front wheel 2f is about to be locked due to the excessively large braking force or a decrease in the coefficient of friction of the road surface, the angle of deceleration of the front wheel 2f then increases suddenly. As a result, the pressure from the pressure plate 89 exceeds a predetermined level, and the lever 91 is turned about the support shaft 90 as a fulcrum so as to further compress the spring 94, so that the second arm 91b of the lever 91 is turned so as to be removed from the valve body 67. This causes the pressure discharge valve 20 to be opened.
When the pressure discharge valve 20 is opened, the hydraulic pressure in the hydraulic control chamber 18 is discharged to the oil tank 19 via the oil passage 70, inlet chamber 68, valve port 66, outlet chamber 69, oil passage 71, inlet chamber 31 in the hydraulic pump 16, and pipe 37. Therefore, the pressure reduction piston 46 is moved toward the hydraulic control chamber 18 by the hydraulic pressure from the hydraulic output chamber 55 against the resilient force of the return spring 48. Consequently, the valve rod 62 is moved back to close the valve body 60, shut off the hydraulic input and output chambers 54, 55 from each other and increase the capacity of the hydraulic output chamber 55. In consequence, the hydraulic braking pressure applied to the front wheel brakes 3f, 3f decreases, and the braking force for the front wheel 2f decreases. This can prevent the front wheel 2f from locking. As a result, the front wheel 2f is accelerated, and the lever 91 is released from the pressure from the pressure plate 89, so that the lever 91 pivots to its original position due to the resilient force of the spring 94 to close the pressure discharge valve 20. When the pressure discharge valve 20 has been closed, the pressure oil discharged from the hydraulic pump 16 is trapped immediately in the hydraulic control chamber 18, and the reduction piston 46 is moved back toward the hydraulic output chamber 55 to increase the pressure in the chamber 55 and regain the braking force. Since such operations are repeated at a high speed, the front wheel 2f can be braked very efficiently.
Referring to FIG. 7, each of the telescopic forks 9l, 9r is provided with a bottom case 120, and a fork pipe 121 fitted slidably in the bottom case 120. At the lower end of the bottom case 120, an end portion of the axle 10 is supported fixedly by a holder 122. In the interior of the bottom case 120, a seat pipe 123, which is concentric with the bottom case 120, is fitted firmly in such a manner that a piston 124 formed integrally with and at the upper end portion of the seat pipe 123 slidably engages the inner circumferential surface of the fork pipe 121. In the interior of the fork pipe 121, a suspension spring 125 is provided between the upper end portion thereof and the piston 124 so that the spring 125 urges the relative fork 9l, 9r in the extending direction thereof. A buffer valve means 126 having an orifice and a check valve is provided between the inner surface of the lower end portion of the fork pipe 121 and the outer surface of the seat pipe 123. The upper and lower hydraulic chambers 127, 128, which are communicated with each other via the buffer valve means 126, are formed around the seat pipe 123.
A partition member 129 is provided between the lower end portions of the bottom case 120 and seat pipe 123. As a result, a hydraulic relay chamber 131, which is communicated with a reserve oil chamber 130 on the inner side of the seat pipe 123 and fork pipe 121, is defined in the lowermost portion of the interior of the bottom case 120. A check valve 132, which permits the oil to flow in only one direction from the hydraulic relay chamber 131 to the lower hydraulic chamber 128, is provided on the upper portion of the partition member 129.
An anti-dive unit 133 is provided on the front surface of the lower portion of each of the telescopic forks 9l, 9r or the bottom case 120 in one of the forks 9l, 9r. This anti-dive unit 133 is provided with a housing 137 having an upper port 134 communicated with the lower hydraulic chamber 128, a lower port 135 communicated with the hydraulic relay chamber 131, and a valve chamber 136 communicating these ports 134, 135 with each other, a valve seat 139 positioned between the ports 134, 135 and held on a shoulder portion of the valve chamber 136 by a retainer spring 138, a valve body 140 held in the valve chamber 136 so as to open and close the same in cooperation with the valve seat 139, and a valve spring 141 urging the valve body 140 in the valve-open direction. The rear surface, which faces in the direction opposite the valve seat 139, of the valve body 140 is provided with a piston 142 formed integrally with the valve body 140 and extending to the outside of the valve chamber 136. This piston 142 defines a pressure receiving chamber 143 within the housing 137. This pressure receiving chamber 143 is communicated with the output port 5fa of the front master cylinder 5f via a pipe 144.
While the front master cylinder 5f is not in operation, the valve body 140 in the anti-dive unit 133 is open. When the front fork 9 starts contracting with the valve body 140 open, the pressure in the lower hydraulic chamber 128 increases, and the upper hydraulic chamber 127 is vacuumed. Accordingly, the oil in the lower hydraulic chamber 128 flows with a low flow passage resistance into the upper hydraulic chamber 127 through the check valve in the buffer valve means 126, and also into the hydraulic relay chamber 131 through the upper port 134, valve chamber 136 and lower port 135, the oil being further flowing into the reserve oil chamber 130 with substantially no resistance. As a result, a slight damping force occurs in the buffer valve means 126, and substantially no damping force in the anti-dive unit 133.
Conversely, when the front fork 9 starts extending, the pressure in the upper hydraulic chamber increases, and the lower hydraulic chamber is vacuumed. Accordingly, the oil in the upper hydraulic chamber 127 flows with a high flow passage resistance into the lower hydraulic chamber 128 through the orifice in the buffer valve means 126. At the same time, the oil in the reserve oil chamber 130 flows into the lower hydraulic chamber 128 through the hydraulic relay chamber 131, lower port 135, valve chamber 136 and upper port 134. As a result, a strong damping force occurs in the buffer valve means 126. However, substantially no damping force occurs in the anti-dive unit in the same way as in the above-mentioned case.
When the front master cylinder 5f operates to actuate the front wheel brake 3f, the output hydraulic pressure therefrom is transmitted to the pressure-receiving chamber 143 as well in the anti-dive unit 133 to press the piston 142 downward. Consequently, the valve body 140 is set on the valve seat 139, and the valve chamber 136 is closed or limitedly opened. When the front fork 9 then starts contracting, the passage of the oil in the lower hydraulic chamber 128 through the valve chamber 136 is stopped or greatly limited, so that a great damping force occurs. This enables the contraction of the front fork 9 to be suitably restricted.
Conversely, when the front fork 9 starts extending the oil in the reserve oil chamber 130 flows to open the check valve 132 and enter the lower hydraulic chamber 128 with a comparatively low pressure. Therefore, the damping force occurs in the anti-dive unit 133, and the front fork 9 extends substantially in the same manner as in the case where the master cylinder 5f is not in operation.
While the hydraulic braking pressure for the front wheel brake 3f is increased and decreased repeatedly by the anti-lock control unit 7 during an operation of the front wheel brake 3f, a downward load is applied from the chassis to the front fork 9 every time the hydraulic braking pressure is increased, to exert the contracting force thereon. However, the contracting action of the front fork 9 is suitably suppressed by the great damping force generated by the anti-dive unit 133. Accordingly, the grounding load on the front wheel 2f increases immediately to cause the frictional force generated between the front wheel 2f and the road surface to increase quickly. This enables the variations in the angular deceleration of the front wheel to be minimized as shown by a line b in FIG. 9.
FIG. 8 shows a second embodiment of the present invention, in which an anti-dive unit 133 is formed of a braking torque-responding type anti-dive unit. To be more precise, a housing 137 is secured to the portion of the rear surface of a bottom case 120 which is opposed to the brake caliper 14 in a front wheel brake 3f, and a piston 145, which can be moved slidingly in the radial direction of the bottom case 120, is fitted slidably in the housing 137, an oil passage 146, which is opened and closed in accordance with the forward and backward movements of the piston 145, and which has a low flow passage resistance, being provided between the bottom case 120 and housing 137. This oil passage 146 is so provided that a lower hydraulic chamber 128 and a hydraulic relay chamber 131 are in communication with each other. An orifice 147, which shunts the portion opened and closed by and with the piston 145 of this oil passage 146, and which communicates both end portions of the same oil passage 146, is provided in the piston 145.
The housing 137 is further provided therein with a return spring 148, which urges the piston 145 in the direction in which the oil passage 146 is opened, i.e., in the direction in which the piston 145 is moved back, and an operating rod 149 capable of urging the piston 145 in the direction in which the oil passage 146 is opened, i.e., in the direction in which the piston 145 is moved forward. This operating rod 149 is connected to the brake caliper 14 in the front wheel brake 3f via a link 150. One end of a bracket 13 which supports the brake caliper 14 is connected pivotably to the bottom case 120 via a pivot 25' so that the brake caliper 14 is turned or displaced relative to the piston 145 by the braking torque when the brake caliper 14 holds a brake disc 12 therein firmly.
The construction of the remaining portion of this embodiment is substantially identical with that of the corresponding portion of the previously-described embodiment. In FIG. 8, the parts corresponding to those of the previous embodiment are designated by the same reference numerals.
While the front wheel 2f is not braking, the piston 145 in the anti-dive unit 133 is held in a retracted portion due to the resilient force of the return spring 148 to keep the oil passage 146 open. Accordingly, when the front fork 9 then extends and contracts, the oil flows with substantially no resistance between the lower hydraulic chamber 128 and hydraulic relay chamber 131 through the oil passage 146, so that the damping force does not occur in the anti-dive unit 133.
While the front wheel brake 3f is in operation, i.e., while the brake disc 12 is held firmly in the caliper 14, the brake caliper 14 is turned by the braking torque about the pivot 25' toward the piston 145. Consequently, the piston 145 moves forward via link 150 and operating rod 149 to close the oil passage 146.
Therefore, when a downward load is then applied from the chassis to the front fork 9 to cause the front fork to start contracting, the oil in the lower hydraulic chamber 128 flows with a high flow passage resistance into the hydraulic relay chamber 131 through the orifice 147, so that the strong damping force occurs therein. Owing to this damping force, the contracting action of the front fork is suitably suppressed. The suppression of such a contracting action of the front fork 9 is done every time the hydraulic braking pressure for the front brake 3f is increased by the anti-lock control unit 7 in the same manner as in the previously-described embodiment.
When the hydraulic braking pressure applied to a front wheel increases and decreases repeatedly due to an operation of an anti-lock control unit while a front wheel brake is operated, a downward load is imparted from a chassis to a front fork every time the hydraulic braking pressure increases, to cause the front fork to contract. However, since the contracting action of the front fork is restricted by an anti-dive unit, the load on the front wheel on that area of the tire which is contacting the ground increases immediately to enable the frictional force between the front wheel and the road surface to increase quickly. Accordingly, the variations in the angular deceleration of the front wheel can be minimized.
According to the present invention described above, an anti-dive unit to control the contracting action of the telescopic front fork in accordance with an operation of the front wheel brake is provided on the front wheel-supporting front fork. Therefore, the contracting action of the front fork can be suppressed by the anti-dive unit to quickly increase the grounding load on the front wheel every time the hydraulic braking pressure for the front wheel brake is increased by an anti-lock control unit. This suppresses vertical vibration of the chassis, facilitates front wheel braking, thus minimizes variations in the angular deceleration of the front wheel and improves braking efficiency.
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An anti-lock brake system employing an anti-lock control unit between a brake master cylinder and a front wheel brake. The brake system is applied to a damped telescopic front fork and includes an anti-dive device which operates to increase damping force upon application of braking force to the front brake. In a first embodiment, the anti-dive device operates from hydraulic pressure upstream of the anti-lock brake unit. In a second embodiment, reaction force to braking of the wheel is sensed and employed to actuate the anti-dive device.
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BACKGROUND OF THE INVENTION
Various fibrous materials, such as paper, paperboard, fiberboard and cellulose wet-lap, are made by forming a slurry or so-called stock of the fibrous material and other ingredients well dispersed in water and delivering the stock as a ribbon-like jet to a web former, such as the well-known Fourdrinier machine or a twin wire former. The mechanical properties and various other characteristics of the web produced by the web former are to a significant extent controlled by the characteristics of the stock delivered to the former from the headbox, and it is extremely important to the obtaining of high quality in the finished web that the fibers and other ingredients, such as fillers and additives, be thoroughly mixed in micro scale as well as macro scale. It is also important that the fibers be as free as possible of engagement with other fibers in the stock delivered from a headbox, i.e., that the fibers not be entangled in flocs.
Although to a considerable extent mixing of the stock occurs prior to feeding the stock to the headbox, one important function of a headbox is to give the stock a thorough final mixing so that the fibers and other ingredients are dispersed uniformly throughout the jet delivered through the slice opening. Among other important functions of a headbox are: the delivery of a precisely uniform thickness jet across the entire width of the former to ensure that the basis weight of the web is uniform; to deliver the stock jet at a controlled velocity to ensure uniformity of web properties from point to point lengthwise of the web and, particularly in twin wire formers, to control the mechanical properties of the web; to deliver a clean, smooth jet free of disturbances and irregularities, notably, machine direction streaks, waves due to velocity variations, water-hammer phenomena or wake effects from structures inside the headbox, and sprays of free drops.
Various headboxes that have been proposed or used over the past few decades have been equipped with elements intended to fulfill the mixing function of a headbox. Most of these elements are one or another form of obstruction interposed in the path of stock flow through the headbox to generate turbulence which, in turn, produces mixing. The obstructions have included baffles, perforated plates, rods, specially shaped vanes, perforated rolls and plates or sheets disposed parallel to the stock flow. Another approach has involved varying the cross section of the stock flow passages such as by providing projections extending from the walls of the headbox into the flow path. Vibrating plates and rods intended to induce mixing by mechanical vibration of the stock as it flows through the headbox have been tried. The various measures that have been proposed and used to enhance mixing of the stock in headboxes have, of course, been effective to various degrees, including some that have been quite successful. However, many of such measures have required trading off optimum results of one or more other functions of the headbox for improved mixing. For example, perforated plates are prone to clogging and to increasing the extent of floc formation due to the build up of flocs at the plates which break away periodically into the stock flow. Perforated plates and rods and vanes of various types also normally tend to produce wake effects that are reflected in streaks in the web. Some mixing devices have proven to be largely ineffective, for example, vibrating objects. Other mixing devices have been prone to mechanical failure from time to time, thus requiring shutdown of the machine for headbox repairs at very considerable costs in terms of lost production.
SUMMARY OF THE INVENTION
There is provided, in accordance with the present invention, a headbox that produces a well-mixed stock, in both macro scale and micro scale, is of strong, reliable, trouble-free construction, produces a stock layer free of wake effects and other across the sheet disturbances and delivers a smooth, well formed, coherent jet.
The headbox includes, as an important aspect of the invention, a fine-mixing stage that has exhibited the ability to form, for the first time, webs having a greater strength in the cross-machine direction than in the machine direction, i.e., an MD/CD tensile strength ratio of substantially less than 1.0. The structure of the headbox is such that it may be of smaller size and weight than comparable, previously known headboxes while still providing the required strength and rigidity.
The headbox comprises a stock mixing section which includes a rectifier stage constructed to produce a multiplicity of closely-spaced, relatively small-diameter separate streams of stock flowing at substantially higher velocities than the velocities of stock flow in other parts of the mixing section. Preferably, the rectifier stage consists of a pair of transverse plates spaced apart from each other in the direction of stock flow and having equal numbers of holes and tubes connecting the holes in the respective plates, thus to constitute a tube bank. The tubes of the rectifier stage should be of lengths not less than about 5 times, and preferably at least 15 times, the hydraulic diameters in order substantially to eliminate any cross flow tendencies that may exist in the stock flow as it leaves the large-scale mixing stage.
In addition to their function of separating the tubes, the transverse plates of the rectifier stage are structural elements of the headbox that impart strength and rigidity to it, particularly cross-machine rigidity that minimizes deflection of the walls of the stock delivery nozzle. Thus, the transverse plates reduce the need for externally located structural elements, and thus allow a reduction in the size of the headbox, as compared to presently known headboxes. When required, the rigidity of the headbox can be further increased by installing additional plates that extend between the tubes and are connected to the aforementioned pair of transverse plates.
The rectifier stage can, of course, be constructed in other ways, e.g., from a solid piece of material in which the rectifier "tubes" are holes drilled in the piece of material.
The mixing section further includes a fine-mixing stage that is located downstream from, and preferably immediately adjacent, the rectifier stage. The fine-mixing stage is constituted by a chamber of the stock mixing section of the headbox which is divided into a multiplicity of flow passages by closely-spaced planar lamellae oriented (1) substantially parallel to the medial axis in the flow direction of the fine-mixing chamber, and (2) oblique to an axial-transverse medial plane of the fine-mixing chamber, i.e., a plane defined by the axis in the flow direction of the fine-mixing chamber and by a medial line perpendicular to that axis and extending transversely of the fine-mixing chamber. The multiplicity of stock streams are delivered from the rectifier stage to the fine-mixing stage and produce in the passages between the closely-spaced lamellae relatively narrow eddies of low to medium intensity which produce medium to fine-scale mixing of the stock. The nature of the mixing action in the fine-mixing stage of the headbox is described in greater detail below.
The average superficial velocity of stock flow through the fine-mixing stage is substantially less than the velocity of stock flow through the rectifier stage, and the flow at the end of the fine-mixing stage is relatively calm and essentially free of large-scale eddies. The stock flows from the fine-mixing stage into a delivery nozzle defined by opposed converging walls that terminate in a slice opening, and the stock is thus smoothly and relatively rapidly accelerated to the desired delivery velocity. The axes in the flow direction of the nozzle and the fine-mixing stage preferably intersect at an angle of the order of from 95° to 120°. The relatively calm flow at the juncture between the nozzle and the fine-mixing stage permits the stock to turn without generating undesirable disturbances. To this end, the stock-receiving end of the stock delivery nozzle is designed such that the superficial velocity in the direction of flow towards the slice opening is essentially constant in the zone along the top of the fine-mixing (lamellae) stage.
The lengths and hydraulic diameters of the passages in the rectifier stage and the fine-mixing stage are chosen with the objective of creating turbulence of moderate intensity in the form of small to medium scale eddies in the passages between the lamellae. Because those passages are relatively narrow, the eddy currents tend to be predominantly aligned in directions parallel to the lamellae. The lengths and hydraulic diameters of the passages in the rectifier and fine-mixing stages are also chosen with a view to inducing the eddies generated in the fine-mixing section to make, on the average, several revolutions before leaving the fine-mixing section and entering the delivery nozzle, thus sustaining the mixing action within the fine-mixing stage for a relatively substantial period of time. The overall cross section of the fine-mixing stage is established such as to provide a relatively low average velocity of stock flow (of the order of 2 to 5 feet per second) in the fine-mixing stage so that the flow conditions of the stock upon entering the delivery nozzle are smooth and the stock can turn into the nozzle without the generation of large-scale disturbances.
There are a number of advantages resulting from turning the stock through a substantial angle from the downstream end of the fine-mixing stage to the nozzle. As described above, the moderately intense and relatively fine-scale turbulence in the fine-mixing stage is in the form of eddies that tend to be aligned parallel to the lamellae. As those eddies reach the end of the fine-mixing stage, they tend to be progressively peeled away into the nozzle such that the re-combination of individual flows of stock in the passages between the lamellae is by way of, with respect to any selected cross-machine location, a "sampling" of flows from several passages between lamellae. That sampling tends to produce a combined flow in the nozzle composed of layers, each of which comes from a different passage in the fine-mixing stage, but by making the turn, the peeling away of eddies from the passages in the fine-mixing stage takes place progressively and inherently provides a mixing effect on a scale of the order of the total width in the machine direction of the fine-mixing stage. The turning of the stock in entering the nozzle also tends to break up the eddies, enhance the fine-scale mixing of the stock, and prevent large scale eddies from forming.
Extensive testing on a pilot headbox has revealed an unexpected characteristic, the ability to produce a web having a greater strength in the cross-machine direction than in the machine direction (i.e., MD/CD ratios substantially less than 1.0). Although the precise reasons for the tendency for fibers in the web to attain an alignment that is on the average preferential in the cross-machine direction is not completely understood at the present time, such preferential fiber alignment may well result from the tendency for the eddies in the fine-mixing stage to be aligned parallel to the lamellae and the persistence of such alignment in the delivered jet upon smooth rapid acceleration of the flow in the nozzle. It has been found that within the normal ranges of selected relative velocities of the jet and the forming surface (surfaces in twin wire machines with drainage through both wires), fiber orientation and MD/CD ratio can be controlled over a greater range than is possible with presently known headboxes.
A headbox, according to the present invention, may, to considerable advantage, be constructed to form a multi-layer jet for the production in the former of a multi-ply web by providing transverse divider walls, as required, in the mixing and distribution section and in the delivery nozzle to maintain stocks delivered to the headbox from two or more sources separate until just prior to delivery through the slice opening.
In a multi-ply configuration of the headbox, the orientation of the lamellae in the fine-mixing stages of the respective compartments formed by the divider wall or walls can be made substantially different, preferably by skewing the lamellae in one compartment to the opposite hand from the lamellae in the other compartment. The abovementioned tendency for the fibers in the web to reflect the orientations of the lamellae results in a multi-ply web having different fiber orientations in the different layers, thus producing "a plywood effect" in that the fiber orientations in the different layers are at angles to each other and the overall strength characteristics of the total web are greater than the combined strengths of the individual layers of the web.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view in schematic form of an embodiment of a headbox, according to the present invention;
FIG. 2 is a diagram depicting very schematically on a relatively large scale the flow conditions in the fine-mixing section of the headbox of FIG. 1;
FIG. 3 is a cross-sectional view on an enlarged scale of a portion of the fine-mixing section taken along a plane substantially perpendicular to the axis in the flow direction;
FIG. 4 is a cross-sectional view on a larger scale of a portion of the rectifier and fine-mixing stages of the headbox of FIG. 1;
FIG. 5 is a pictorial view in schematic form of a multi-ply headbox; and
FIG. 6 is a side view showing the details of a mounting for a divider wall in the nozzle of the multi-ply headbox of FIG. 5, the view being of the region enclosed in the circle labelled "See FIG. 6" in FIG. 5.
DESCRIPTION OF EXEMPLARY EMBODIMENTS
The headbox shown in FIG. 1 comprises a mixing and distribution section, which consists of a large-scale mixing stage 1, a rectifier stage 2 and a fine-scale mixing stage 3, and a delivery nozzle 4 composed of converging top and bottom walls terminating in a slice opening 5. Stock is delivered to the headbox from a cross-machine distributor 6 through a number of stock feed pipes or hoses 7.
The large-scale mixing stage of the headbox is simply an open chamber which receives stock at relatively high velocity from inlets from the pipes 7, which pipes may be anywhere from about 1 inch to 3 inches in diameter and spaced on a center-to-center distance of about twice the diameter. The entry of the streams of stock into the mixing chamber produces fairly intense, large-scale eddies and some degree of cross flow to provide mixing and distribution of the stock on a large scale. The chamber is made large enough so that the average velocity of flow through it is relatively low and flow disturbances resulting from velocity variations within the flow in the stage 1 will have only a negligibly small effect on conditions in the rectifier stage 2. The turbulence in the large-scale mixing stage keeps the lower (upstream) surface of the tube bank (described below) clean and free from lumps of stock that might otherwise build up on the entrance edges of the tubes.
The rectifier stage 2 consists of an array of tubes 8, each of which is of relatively small diameter and great length. In particular, the lengths of the tubes are sufficiently long to substantially eliminate any cross flow tendency that may exist in the flow as it leaves the mixing stage 1. In general, the tubes should have a length of not less than 5 times the hydraulic diameter and preferably a length of at least 15 times the hydraulic diameter. The tubes 8 extend between a pair of transverse plates 11 and 12 (see FIGS. 3 and 4) that are spaced from each other in the flow direction and are strongly secured to the perimeter walls of the headbox, thus to impart rigidity and strength to the headbox. The tubes are arranged in diagonally extending rows that are centered between plates or lamellae 9 of the fine-mixing stage 3 (described below and see FIG. 3), the tubes in each row being equidistant from each other and the rows being equidistant from each other. Generally, the spacings between the tubes in each row will be somewhat greater than the spacings between the rows, a situation that is controlled by the construction and mode of operation of the fine-mixing stage 3. The overall pattern of the tubes should, of course, be such as to provide an even distribution of stock flow across the headbox.
It is advantageous from the point of view of strength and rigidity of the headbox to install stiffeners 13 extending diagonally parallel to and between the tube columns in the shorter direction between opposite walls of the headbox and extending in the flow direction (axially) between the tube-mounting plates 11 and 12.
The fine-mixing stage 3 is a section of the headbox containing a series of planar lamellae 9. The lamellae are oriented parallel to the axis of the fine-mixing stage in the flow direction and oblique to an axial-transverse medial plane of the fine-mixing stage, thus to form a multiplicity of narrow separate flow passages that lie parallel to the axis of the headbox and oblique to the cross-machine direction. Each row of tube outlets 10 is located parallel to and centered between an adjacent pair of the lamellae.
The flow conditions and the mixing action that occur in the fine-mixing stage 3 of the headbox are shown very schematically in FIG. 2. The streams of stock established by flow through the tubes 8 in the rectifier stage enter the fine-mixing stage at a relatively high velocity and upon encountering the stock in the fine-mixing stage, which is flowing at a substantially lower velocity, form relatively small eddies B of low to medium intensity. Because the spacing between the lamellae is relatively small, the eddies tend to become aligned parallel to the lamellae so that the overall flow in each passage between adjacent lamellae is made up predominantly of eddies circulating in planes generally parallel to the lamellae. The eddies move at relatively low average, superficial velocity in the direction of the tubes of the tube bank, preferably in the range of from about 2 to 5 feet per second, up through the passages between the lamellae. The interaction of the eddies as they are generated and move slowly through the fine-mixing stage provides a very effective fine-scale mixing action of relatively long duration. The skewed orientations of the passages between the lamellae also provide an opportunity for some cross flow to occur, thereby tending to eliminate any residual cross flow tendencies. The spacing between the lamellae 9, the distances between outlets 10 of the tubes in each row between adjacent lamellae, and the diameters of the tubes should be such that the eddies formed in the fine-mixing stage circulate on the average through several revolutions before leaving the fine-mixing stage.
The lamellae should, of course, be suitably fastened at each end to the walls of the headbox. The fact that the lamellae are oriented oblique to the axial-transverse medial plane of the fine-mixing stage makes them of relatively short length. Thus, they can be made of thin sheet material while still being sufficiently strong and durable to endure the relatively low intensity flow conditions of the stock as it moves through the passages between them. The heights of the lamellae in the flow direction should be not less than about 3, and preferably at least 5 times the perpendicular distance between them, which distance should be of the order of 3/4 inch.
Upon leaving the fine-mixing stage 3, the stock enters the delivery nozzle 4 and in so doing makes a turn through a substantial angle, preferably of from about 60° to 85°. The stock leaves the fine-mixing stage at a relatively low velocity and essentially free of large-scale turbulence and thus is able to make the turn into the nozzle with a minimum of disturbance in the flow.
As depicted schematically in FIG. 2, the combined flow C of stock entering the nozzle 4 is, at any given cross-machine direction, made up of "samples" of stock that are "peeled" away successively from adjacent passages between the lamellae 9 in the fine-mixing stage. In making the abrupt turn from the fine-mixing stage to the nozzle, the eddies tend to be broken up. The stock flow in the nozzle tends, however, to remain layered with little physical intermixing of the layers, but the successive sampling effect of the peeling of stock flows from each passage in the fine-mixing stage produces additional mixing of the stock in the sense of combining in the nozzle elements of stock flowing from the different passages at different times. Thus, an element of stock flowing from portions of passages between the lamellae near the back of the headbox, relative to the slice opening 5, combines successively with elements of stock flowing from portions of the passages nearer the slice opening.
The length of the nozzle should be as short as possible in order to provide fast acceleration of the stock to the slice opening with a minimum of turbulence generation resulting from hydraulic shear adjacent the walls of the nozzle. On the other hand, the distance between the slice opening and the landing position of the jet in the former should be kept small. Therefore, the nozzle will generally be of a length that requires convergence of the nozzle walls at angles α (see FIG. 1) of from about 2° to 6°. The top and bottom walls of the nozzle may, if desired, be curved rather than straight.
Referring to FIG. 5 of the drawings, a headbox, according to the present invention, may be constructed to deliver a jet composed of separate layers of stock (separate in that there is little co-mingling between the stocks of the layers at the interfaces between them) for the production in the former of a multi-ply web. In the embodiment of FIG. 5, the distribution and mixing section of the headbox is composed, in essence, of three compartments separated from each other by divider walls 20 and 21 in the large-scale mixing stage 1 and the fine-mixing stage 3, such divider walls extending axially and transversely to form separate cross-machine compartments. Stock is delivered from separate distributors 6 through separate pipes 7 to the different compartments. Similarly, the delivery nozzle 4 is subdivided by divider walls 14 that extend transversely and in the flow direction and define three passages converging at angles α 1 , α 2 , and α 3 .
In the embodiment shown in FIGS. 5 and 6, the divider walls 14 in the nozzle are stainless steel plates bent at their upstream ends to form flanges 16 (see FIG. 6). Each divider wall 14 is fastened at its upstream end to a holder formed by a jaw 22 provided on the upper end of the divider wall 21 of the fine-mixing stage and a jaw 17 fastened by screws 19 to the jaw 22. The flange 16 of the divider wall 14 is received and held in a slot 15 in the jaw 22 by a rod 18 that presses down on top of the divider wall 14 within the opening between the jaws. The divider walls 14 extend downstream in the nozzle and terminate a short distance, say about 2 inches, from the slice opening 5. Thus, the layers of stock are maintained separate until just before the stock is discharged through the slice opening.
In order to prevent warping of the divider walls 14 in the cross-machine direction, it is advantageous to construct and orient the jaws 17 and 22 in such a way that the divider walls 14 are held in positions in which they do not line up exactly in the direction of stock flow but point slightly below the slice opening. The hydraulic forces of the stock flow will then slightly bend the separating walls 14, and the imposed curvature, as depicted schematically by the arrowed lines "R" in FIG. 6, in the "vertical" direction ("vertical" as related to the drawings of FIGS. 5 and 6) will effectively prevent warping of the walls 14 in the cross-machine direction.
The form of divider walls 14 and the manner of installing them in the nozzle in the embodiment of FIGS. 5 and 6 are merely exemplary of various ways in which the delivery nozzle of the headbox can be subdivided into separate channels, and various other ways, including some that are known in the art, may be employed. For example, the divider walls may be tapered plates that are of substantial thickness at their upstream ends, tapered to thin tips or sharp edges at their downstream ends, the mounted on pivots or connected by hinge-type connections to supports, such as the tops of the divider walls 21, at the entrance to the nozzle.
The tendency for fiber orientation in the web to reflect the orientation of the lamellae in the fine-mixing stage of a headbox constructed in accordance with the present invention can be used to considerable advantage in a multiply headbox of the type shown in FIG. 5. In particular, the lamellae in the fine-mixing stage of one compartment can be oriented at a substantially different angle, preferably an angle of the opposite hand from the lamellae in other compartments. Thus, as shown in FIG. 5, the lamellae in the center compartment of the fine-mixing stage are oriented at an angle that is of a hand opposite from that of the lamellae in the outer compartments. The web formed of stock delivered from the headbox 5 will have fibers in the outer two layers oriented differently from the fibers of the middle layer, and the web will have a stiffness and strength greater than the sums of the stiffnesses and strengths of the individual layers and other mechanical properties that are enchanced by a "plywood" effect.
In some cases, it may be desirable to provide turning vanes at the intersection between the distribution and mixing section and the delivery nozzle of the headbox. In such cases, a construction very similar to that shown in FIG. 5, but with divider walls that extend only a few inches downstream from the end of the fine-mixing section into the delivery nozzle, can be provided. With such a construction, the layers delivered from the separate compartments of the fine-mixing stage will intermix to a somewhat greater extent than in the multi-ply configuration illustrated in FIG. 5. Similarly, the extent of intermixing of layers in a multiply configuration is subject to some control by varying the lengths of the divider walls 14 in the downstream direction, i.e., by varying the distance between the downstream ends of the divider walls and the slice opening. To this end, the divider walls may be built and installed in a manner that permits adjustment of the distance between the downstream tips of the divider walls and the slice opening.
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Finely-mixed stock is produced in a headbox by delivering a multiplicity of separate stock streams at a relatively high velocity into passages defined between closely-spaced planar lamellae which extend parallel to the stock flow and oblique to a medial plane that lies axially and transversely of the fine-mixing stage that contains the lamellae. The stock flows at relatively low velocity in finely-mixed condition from the fine-mixing stage to a discharge nozzle, the axis of which lies at a substantial angle to the axis of the fine-mixing stage. The stock distribution and mixing section and the delivery nozzle of the headbox may be divided axially and transversely into two or more separate compartments for discharge of a jet composed of layers of the same or different stocks to form multi-ply webs. Different fiber orientations in different layers of such a multi-ply web are obtained by orienting the lamellae in the different chambers at substantially different oblique angles to the aforementioned axial-transverse medial plane of the fine-mixing stage.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation of divisional of Ser. No. 10/079,688 filed Feb. 20, 2002, which is a divisional of U.S. Pat. No. 6,419,781 issued Jul. 16, 2002.
FIELD OF THE INVENTION
[0002] This invention relates to the area of stickers. More particularly, this invention relates to making stickers from index prints that are produced when a photographic film is developed.
BACKGROUND OF THE INVENTION
[0003] Stickers can be both fun and functional and are used by people of all ages and sexes. Children collect stickers and use them to decorate any number of items. Adults likewise use stickers to decorate items, and may also use them as labels or as a way to hold envelopes closed. There are several types of stickers that are commercially available, but it is not possible for consumers to buy personalized stickers made with the consumer's own photographs.
[0004] Index prints are available to consumers after a film is developed. These index prints contain small thumbnail images of each photographic image that appears on the film. The goal of index prints is to aid the consumer in identifying which photographs appear on which film negative. Unfortunately, the index print often gets separated from the film negatives and as such, has limited value for its intended purpose.
SUMMARY OF THE INVENTION
[0005] The present invention combines the fin of stickers with the utility of index prints. By printing an index print as stickers, the present invention allows a consumer to peel off and use a personalized sticker. Alternately, the present invention allows the consumer to leave the stickers in place for an intact index print.
[0006] Index sticker prints are made by providing a sticker blank carrier with a specific number of sticker blanks. Since most films contain a maximum of thirty-six exposures, but may allow for taking a few extra pictures, the number of stickers blanks is set at greater than thirty-six.
[0007] A photographic film image is scanned to produce digital image data for each image on the film. Once this digital image data is collected, the data can be formatted to produce images of a size corresponding to the size of the sticker blanks. In printing the stickers, each individual digital image corresponding to each photographic image on the film is printed on a sticker blank. This results in one sticker of every image on the film. If there are more stickers blanks than there are photographic images on the film, some photographic images can be repeated to fill the empty sticker blanks. Once the printing is complete, the finished stickers are dispensed to the consumer who can then peel and use the stickers from their backing as stickers.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] [0008]FIG. 1 is a flow diagram of the process for creating an index sticker print;
[0009] [0009]FIG. 2 is the top view of a sticker blank carrier;
[0010] [0010]FIG. 3 is a graphic depiction of an index sticker print; and
[0011] [0011]FIG. 4 is an enlarged side view of the index sticker print.
DETAILED DESCRIPTION OF THE INVENTION
[0012] [0012]FIG. 1 is a flow diagram setting out the process for creating an index sticker print. First step 10 is to provide a sticker blank carrier 20 as shown in FIG. 2. Second step 12 requires that film images be scanned to get digital image data. Third step 14 formats the digital image data so that each image will fit on a sticker blank 22 . Next, fourth step 16 requires that the images be printed onto sticker blanks 22 . Fifth step 18 is simply to dispense the results to a consumer.
[0013] [0013]FIG. 2 shows a sticker blank carrier 20 ready for printing. The carrier 20 consists of several individual sticker blanks 22 . Each sticker blank 22 has a precut edge 24 to allow the sticker blank 22 to be peeled off a backing 26 . The backside of the sticker blank 22 has an adhesive coating 28 that allows the user to adhere the sticker onto another surface.
[0014] The sticker blank carrier 20 has greater than thirty-six sticker blanks 22 , and more preferably, greater than thirty-nine sticker blanks 22 . Each sticker blank 22 is of a predetermined size such that they can be arranged and placed on the sticker blank carrier 20 . The carrier 20 shown in FIG. 2 has forty sticker blanks 22 . Films commonly come in twenty-four or thirty-six exposures, but may allow for a few extra pictures to be taken, resulting in slightly over twenty-four or thirty-six photographs. Thus, if there are greater than thirty-six sticker blanks 22 on the sticker blank carrier 20 , it can be ensured that every image on a film can be printed at least once as a sticker. If there are more sticker blanks 22 than there are photographic images on the film, certain selected photographic images can be repeated and printed again on the empty sticker blanks 22 . Alternatively, the empty sticker blanks 22 can be filled by simply repeating images from the beginning of the film and printing those images in the empty sticker blanks 22 .
[0015] [0015]FIG. 3 is a graphic representation of an index sticker print 30 . On each stamp blank 22 a thumbnail image 32 has now been printed, creating an index sticker 38 . The thumbnail image 32 is slightly larger than the sticker blank 22 , such that the precut edges 24 fall on the inside of the thumbnail image 32 and truncate it. A border 40 surrounds the stickers 38 . On this border 40 it is possible for other indicia 36 to be printed, such as date, company identification, or other notations or descriptions. The stickers 38 are arranged in rows and columns and may be identified with an index number 42 . The index numbers 42 are normally printed at the same time the thumbnail images 32 are printed on the sticker blanks 22 . The index number 42 could also be printed on the backing 34 rather than the sticker 38 .
[0016] [0016]FIG. 4 shows an enlarged side view of the index sticker print 30 . FIG. 4 makes clear that the index sticker 38 is coated with an adhesive layer 52 on its bottom surface. Thus the stickers 38 can be peeled from the backing 54 and adhered to another surface. There are many options for composition of the adhesive layer 52 . Any adhesive that is strong enough to adhere to several surfaces, but not so strong as to prevent it from being removed from the backing 54 would be suitable. Several such adhesives are available and are well known in the art. Likewise, several options exist for the materials used for the stickers 38 and the backing 54 which are well known in the art.
[0017] In collecting the digital image data as noted in Step 2 of FIG. 1, a scanner may be used to scan a photographic film negative. When using a scanner, the photographic film negative image is projected onto a linear scanner. The scanner scans the image and collects an electronic representation of it. One such scanner that is suitable is the Pakon Film Scanner described in U.S. Pat. No. 5,872,591 issued Feb. 16, 1999. Once collected, this electronic image is converted into digital image data which can be formatted to make the image suitable for printing. Formatting may consist of sizing, sharpening, or otherwise manipulating the digital image data to prepare it for printing. Once formatted, the digital image data can be sent to a printer.
[0018] The index sticker print 30 can be created by using an ink jet printer capable of at least 300 dpi. Once such printer is the Desk Jet 1200C manufactured by Hewlett Packard®. The printer receives the digital image data and uses it to print the thumbnail image 32 on the sticker blanks 22 , creating an index sticker print 30 corresponding to the photographic images on the photographic film negative. When finished printing, a completed index sticker is dispensed to the consumer.
[0019] Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.
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An index sticker print is created where small photographic images are printed on individual sticker blanks contained on a sticker blank carrier. The photographic images are derived from digital image data obtained when the photographic film is scanned. The digital image data is formatted to size and is sent to a printer which then prints the digital data onto the sticker blanks creating an index sticker print.
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BACKGROUND OF THE INVENTION
The present invention pertains to circuitry for sequentially energizing a plurality of lights and, more particularly, to such circuitry possessing the capability of being programmed to provide a number of different lighting sequences.
Among the uses which are contemplated for the circuitry of the present invention are the controlling of a plurality of strings of Christmas tree lights, the controlling of lights used in commercial displays, such as store window displays, and the controlling of other decorative lighting arrangements.
To enhance the aesthetic effect of decorative and display lighting, it is often desirable to provide for the blinking or flashing of the lights. For example, it is a common practice to provide, with Christmas tree lights of the series type, for each set of series lights one bulb which includes a thermally responsive switch to cause the lights of that particular series to flash or blink. With the use of individual thermally responsive switching for each light string, however, the flashes of the individual strings are purely random relative to the other strings and it is not possible to create selected patterns or sequences in the blinking of the light strings.
Sequencing controllers which employ mechanically operated switches have been proposed for the control of multiple strings of decorative lights. Examples of such controls may be found in U.S. Pat. Nos. 2,878,424, Barker; 3,808,450, Davis Jr.; 3,862,434, Davis, Jr.; and 4,057,735, Davis, Jr. Sequencing controllers of this type, however, employ motor driven cam operated switches and are, of necessity, of fairly large size. Where the sequencing controller is used to control the lights of a Christmas tree, many people find the use of a large size control unit to be objectional as such a unit is not easily concealed and, thus, detracts from the desired decorative effect. Also, the mechanical sequencing controllers of the prior art are generally designed to provide but a single sequence for the plural light strings.
Another approach to controlling a display of decorative lighting suggested by the prior art is that disclosed in U.S. Pat. No. 3,793,531, Ferrigno. In the approach adopted in this patent, a solid-state control circuit is employed with the display lights being switched on and off by means of a Triac which is gated by means of an oscillator circuit to turn on and off at selected portions of the half cycles of a standard 60 Hz alternating current signal. Here again, however, only a limited sequence is provided. Another approach to the control of plural display lights also using solid-state circuitry is taught in the article "Solid-State Ring Counters and Chasers for Light Displays" A. A. Adem, Electronics World, September 1967, pp. 84-85. In this circuit each light or series of lights is controlled by a solid-state switching device such as a Triac or an SCR and the switching device is, in turn, gated by a stepping circuit so that the lights are triggered in a predetermined but fixed sequence. A similar sequencing controller for display lights is disclosed in U.S. Pat. No. 3,934,249, Sanjana.
It is the primary object of the present invention to provide a sequencing light controller employing solid-state circuitry and having the capability of providing a number of different sequences readily selectable by the user.
A further object of the present invention is the provision of a sequencing light controller which may be housed in a compact unit so as to be unobtrusive when used in connection with decorative displays or Christmas tree lighting.
Yet another object of the present invention is the provision of a sequencing light controller having the capability of controlling a plurality of strings or banks of lights.
BRIEF DESCRIPTION OF THE INVENTION
The above and other objects of the invention which will become apparent hereinafter are achieved by the provision of a sequencing light controller having a plurality of electric outlets to which individual light strings may be connected, a Triac or equivalent solid-state switching device for connecting each of the outlets to an AC power source, a gating circuit for each Triac, a timing circuit, and a logic circuit having a plurality of output sequences connected to the gating circuits and controlled by the timing circuit to provide selective sequential energization of the Triacs and, accordingly, light means connected thereto.
For a more complete understanding of the invention and the objects and advantages thereof, reference should be had to the following detailed description and the accompanying drawings wherein preferred embodiments of the invention are described and shown.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a perspective view of the first embodiment of the light sequencing controller of the present invention;
FIG. 2 is a side elevational view of a second embodiment of the sequencing controller;
FIG. 3 is a top plan view of the embodiment of FIG. 2;
FIG. 4 is a schematic showing of one embodiment of the sequencing circuitry of the present invention;
FIG. 5 is a schematic showing of a second embodiment of the sequencing circuitry;
FIG. 6 is a schematic showing of another embodiment of the sequencing control circuitry; and
FIG. 7 is a schematic showing of yet another embodiment of the sequencing control circuitry.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The light sequencing controller illustrated in FIG. 1 includes a housing 10 containing the sequencing control circuitry to be hereinafter described and is provided with a power cord 12 having a plug 14 for connection to a standard 110 volt 60 Hz outlet. A plurality of outlet receptacles 16 and 18 are connected to the housing 10 by a multiconductor cable 20. The housing 10 also includes an on-off switch 22, a sequencing mode selector switch 24, an indicator light 26 and a circuit breaker reset button 28.
In the embodiment illustrated in FIGS. 2 and 3, the housing 30 for the sequencing control circuitry is designed to be attached directly to an outlet receptacle, the electrical connecting prongs 32 projecting directly from the rear face of the housing 30. As with the previously described embodiment, multiple outlet receptacles 36 and 38 are connected to the housing 30 by means of a multiconductor cable 34. Projecting from the forward face of the housing are a switch 40 which may be a combined on-off and mode selecting switch, an indicator light 42 and a circuit breaker reset button 44.
One embodiment of the sequencing control circuitry which may be used with the assembly of FIG. 1 or that of FIGS. 2 and 3 is illustrated in FIG. 4. In this embodiment the power cord 12 connects to a pair of buses 50 and 52. The bus 52 includes a protective circuit breaker 54 and an on-off switch S1, which may be the switch 22 of FIG. 1 or a portion of the switch 40 of FIGS. 2 and 3. The bus 50 also connects to one conductor 66 of the multiple conductor cable 20 or 34 and is, in turn, connected to one side of each of the outlet receptacles 16A, 16B, 18A and 18B. The opposite sides of these receptacles are connected by means of conductors 68, 70, 72 and 74 to one main terminal of Triacs 56, 58, 60 and 62, respectively. The second main terminal of each of these Triacs is connected to the second bus 52. The conductors 68-74 constitute the remaining conductors of a multiple conductor cable. Also connected across power supply buses 50 and 52 is the primary of a transformer T1, the secondary of which furnishes, through a full wave rectifier constituted of the diodes D5-D8, a DC voltage in conductor 64 for the timing and sequencing control circuitry to be described below. An indicator light 26 is also connected across the buses 50 and 52. This indicator lamp may be a standard NE-2 neon pilot lamp.
The sequencing control circuitry includes a timer 76 which may be a linear integrated circuit timer manufactured by Signetics and designated part number NE555V. This timer functions as a stable oscillator with its frequency being controlled by means of the variable resistor 80. The timer functions to produce clock pulses in line 78 at uniform time intervals. The clock pulses over line 78 are provided as clock inputs to a counter/decoder 82 which may be a decade counter/divider manufactured by Motorola Semi-Conductors and designated part number MC14017B. This device has ten output terminals which are successively energized on successive clock pulses supplied to the device. In the present embodiment, only the first seven outputs a-f are employed. Upon initiation of a cycle the a output of a counter/decoder 82 is energized while outputs b-f are de-energized. When a clock pulse is transmitted over the line 78, the a output becomes de-energized and the b output energized. The a output of the counter/decoder is connected bia a conductor 84 to the base of a switching transistor Q1; the b and q outputs via conductors 86 and 88 to the base of switching conductor Q2; the c and f outputs via conductors 90 and 92 to the base of switching conductor Q3; and the d output via conductor 94 to the base of switching conductor Q4. Output e is connected to one terminal A of the switch S2, via the conductor 96. The g output is also connected, via a conductor 101 to the B terminal of the switch S2. The transistors Q1-Q4 furnish gating signals to Triacs 56-62, respectively, via conductors 102-108. The switch S2 is connected via conductor 98 to the reset input 100 of the counter/decoder 82.
Upon initiation of a sequencing cycle, the a output of the counter/decoder 82 provides a biasing signal to transistor Q1 turning this transistor on and furnishing a gating signal to Triac 56 so that Triac 56 conducts thereby energizing the lamp or series of lamps connected to the outlet 16a. When a clock pulse is transmitted from the timer 76 to the counter/decoder 82 the a output is de-energized turning transistor Q1 and Triac 56 off. At the same time, the b output is energized biasing transistor Q2 on and furnishing a gating signal to Triac 58. In like manner, outputs c and d are sequentially energized sequentially triggering on Triacs 60 and 62. If the switch S2 is in the A position the next succeeding clock pulse, causing the e output of the counter/decoder to be energized, furnishes a reset signal to the counter/decoder so that the next succeeding pulse again triggers the a output. When the switch S2 is in the B position, the e output terminal of the counter/decoder is disconnected and, upon receipt of the next clock pulse the f output is energized again biasing on transistor Q3 and the corresponding Triac 60. The next succeeding clock pulse causes the g output to turn on thereby turning on Triac 58. The g output signal is also supplied through conductor 101, switch S2 in the b position and conductor 98 to furnish a reset signal to the counter/decoder. Thus it will be seen that the circuit of FIG. 4 provides two sequences for the lamps commected to the outlets 16A, 16B, 18A and 18B. When the switch S2 is in the A position the lamps are energized in an L1, L2, L3, L4 and repeat sequence. In the B position, the lamps are energized in a sequence of L1, L2, L3, L4, L3, L2 and repeat. It will be understood that while for clarity in the drawings only a single lamp is shown as being associated with each of the outlet receptacles, in actual practice, a plurality of lamps would be associated with each receptacle. For example, an individual string of Christmas tree lights may be connected to each of the receptacles so that four strings of lights are controlled by the sequencer control circuit.
The circuit embodiment disclosed in FIG. 5 provides two sequencing modes for controlling the lights connected to the outlet receptacles and a third mode in which all of the lights are energized. As in the previously described circuit, each of the outlet receptacles 16A, 16B, 18A and 18B is connected to the power supply buses through a Triac 56, 58, 60 and 62, respectively, and each Triac is gated by a corresponding switching transistor Q1, Q2, Q3 and Q4, respectively. Also as in the previously described embodiment, a timer 76 provides clock pulses via line 78 to a counter/decoder 82. The sequential outputs of the counter/decoder 82 are supplied to an array of logic elements 120-144 to determine the sequence of energization of lamps L1-L4. The mode selecting switch S2a provides enabling signals to selected ones of the logic elements to determine the particular sequence. Thus, when the switch S2a is in the number 1 position, an enabling signal is provided to OR gate 142 and to one of the inputs of AND gate 144. The OR gate 142 furnishes enabling signals to one input of each of AND gates 126, 128 and 130. In this mode, the a output of the counter/decoder serves as an input to OR gate 120, turning this gate on to provide a signal to the base of transistor Q1. The b output of the counter/decoder is supplied to OR gate 122 which, in turn, supplies a signal to transistor Q2. The b output also provides an enabling signal to the first imput of AND gate 126 and, since the OR gate 142 also provides an enabling signal to the second input of AND gate 126, gate 126 furnishes an output signal to OR gate 120. Likewise, the c output provides a second enabling input to AND gate 128 so that an enabling signal is furnished to both gate 120 and 122. The c output signal is also coupled to the input of OR gate 132, the output of this gate furnishing an input to OR gate 124 to furnish a biasing signal to transistor Q3. At the next succeeding clock pulse, the d output of the counter/decoder is energized which provides an enabling signal to OR gate 138 to furnish a biasing signal to transistor Q4 and a second enabling signal to AND gate 130 which, in turn, furnishes enabling signals to OR gates 120, 122 and 124. The next output of the counter/decoder, at the e terminal, is furnished to AND gate 136. However, the second enabling signal to this gate is not present. The e output is also supplied to AND gate 144 which is receiving a second enabling signal through the switch S2a. Consequently, gate 144 furnishes an output signal to OR gate 140. Or gate 140 outputs to OR gate 138 again biasing transistor Q4 and, through gates 130 and 120-124, transistors Q1, Q2 and Q3. The f output signal of the counter/decoder is supplied to AND gate 134. This gate, however, is not energized as the second input terminal is grounded since switch S2a is in the one position. Consequently, no biasing signals are furnished to the transistors Q1-Q4 during the f output interval of the counter/decoder. At the next clock pulse supplied to the counter/decoder the g output is energized to furnish the reset signal to terminal 100.
The circuit of FIG. 5 also includes a zero crossing detector consisting of transistors Q5 and Q6 supplied by the voltage divider network R8, R9 connected across the AC buses 50 and 52. The zero crossing detector circuit serves to provide a positive going pulse at the point of zero crossing of the AC signal which pulse is amplified via transistors Q7 and Q8 to furnish a signal on line 150 to which the collectors of transistors Q1-Q4 are connected. This arrangement assures that the transistors Q1-Q4 will turn on, when provided with biasing signals from the respective OR gates, only at the point of zero crossing of the AC signal so that the corresponding Triacs 56-62 are also turned on only at the zero crossing point. An energized Triac will remain in that state until the AC current again goes to zero and no gating signal is supplied by the corresponding transistor. The provision of the zero crossing circuit serves to minimize radio frequency interference that would otherwise be caused by the switching on and off of the AC loads connected to the outlets 16A, 16B, 18A and 18B.
From the above description of the circuit 5, it will be apparent that when the switch S2a is in the 1 position, the lamps are illuminated in the sequence L1, L1L2, L1L2L3, L1L2L3L4, L1L2L3L4, OFF and repeat.
When the switch S2a is in the number 2 position, an enabling signal is provided to one terminal of each of AND gates 134 and 136. In this mode of operation, the a output of the counter/decoder 82 turns on OR gate 120; the b output turns on OR gate 122; the c output, gates 132 and 124; the d output, gate 138; the e output, gate 136 and gates 132 and 124; and the f output, gate 134 and gate 122. Thus, in this mode of operation the lamps are illuminated in the sequence L1, L2, L3, L4, L3, L2 and repeat.
The number 3 position of the switch S2a provides a full on position for all of the lamps independent of the operation of the timer 76 and counter/decoder 82. When the switch S2a is in the number 3 position enabling signals are provided to the OR gates 140 and 142. The signal of gate 142 provides enabling signals to AND gates 126, 128 and 130. The output signal of OR gate 140 provides and enabling signal to OR gate 138 which furnishes a second enabling signal to AND gate 130 and this gate, in turn, provides an enabling signal to each of OR gates 120, 122 and 124. Since gates 120, 122, 124 and 138 are all enabled, biasing signals are provided to each of the transistors Q1-Q4 at all times. Consequently, the four Triacs 56-62 are gated on at all times.
In the circuit of FIG. 4, the mode selection switch determines the reset point for the counter/decoder circuit while in the circuit of FIG. 5 the mode selection switch programs a gating network to determine the sequence in which the Triacs are energized. FIG. 6 illustrates a circuit in which the mode selecting switch serves both of these functions. In this embodiment, OR gates 210-214 and AND gates 216-224 determine the sequencing pattern by which the Triacs 56-62 are gated on while OR gate 226 and AND gates 228-232 serve to determine the point during the sequence at which the reset signal is generated. This circuit also includes AND gates 202-208 which function in conjunction with a zero crossing detector circuit comprised of transistors Q9 and Q10 to pass gating signals to the transistors Q1-Q4 and, in turn, to the Triacs 56-62 only at the point of zero crossing of the AC power current. As in the previously described embodiment, the function of this circuit is to assure that the Triacs turn on at the point of zero crossing to minimize radio frequency interference.
When the mode selector switch S3b of the circuit of FIG. 6 is in the number 1 position, no enabling signals are provided to the AND gates 216-224. An enabling signal is provided to reset select AND gate 228. In this mode of operation the counter/decoder outputs a, b and c successively trigger on OR gates 210, 212 and 214, respectively, while the d output provides an enabling signal to AND gate 208. The e output of the counter/decoder is supplied to AND gate 228 which, in turn, triggers on OR gate 226 to furnish the reset signal to reset input 100 of counter/decoder 82. The sequence in this mode of operation is L1, L2, L3, L4 and repeat. At the mode 2 position of switch S3b an enabling signal is provided to the AND gates 222 and 224 and the reset select AND gate 230. In this mode of operation, the first four outputs of the counter/decoder, the a, b, c and d outputs, successively trigger on, via the appropriate gates, the Triacs 56, 58, 60 and 62, respectively. The e output provides a second enabling input to AND gate 224 to furnish an input to OR gate 214, again triggering on Triac 60. Likewise, the f output provides an enabling input to AND gate 222 to trigger on Triac 58 through OR gate 212. The g output of the counter/decoder coupled through AND gate 230 provides the reset signal to the counter/decoder 82. In the number 2 mode, therefore, the lamps are triggered in a sequence L1, L2, L3, L4, L3, L2 and repeat.
Enabling signals are provided to the AND gates 216, 218 and 220 and to reset select AND gate 232 when the switch S3b is in the mode 3 position. When operating in this mode, the a output of the counter/decoder 82 triggers on OR gate 210 to provide a gating signal for Triac 56. The b output signal of counter/decoder provides a second enabling input to AND gate 216 so that this gate outputs again turning on OR gate 210 and triggering on Triac 56. The b output signal also triggers on OR gate 212 to trigger on Triac 58. The c output from the counter/decoder provides the second enabling input to AND gate 218 which outputs to turn on OR gates 210 and 212. The c output also triggers on OR gate 214 so that at this stage Triacs 56, 58 and 60 are provided with gating signals. Likewise, the d output provides the second enabling input to AND gate 220 and this gate outputs to turn on OR gates 210, 212 and 214 while the d output is also supplied, through AND gate 208, to gate on Triac 62. As the e output is supplied only to AND gates 222, 224 and 228 which are not enabled, none of the Triacs are turned on during the e output interval. The f output interval is furnished to the reset select AND gate 232 which is enabled so that the reset signal is generated at the f output interval. The sequence in the mode 3 operation is L1, L1L2, L1L2L3, L1L2L3L4, OFF and repeat. The mode 4 output of the sequencer control differs from that of mode 3 in that reset select AND gate 228 is enabled rather than gate 232 so that the e output of the counter/decoder furnishes the reset pulse to provide a sequence of L1, L1L2, L1L2L3, L1L2L3L4 and repeat.
Turning now to FIG. 7, there is disclosed a further modification of the sequencing control circuit of the present invention which provides for nine different sequencing modes and which employs a pair of quad 2-input multiplexers such as Model MM74C157 manufactured by National Semi-Conductor. Each of the multiplexers 300, 320 has four a inputs, 1a-4a, four b inputs, 1b-4b, and four output terminals, 1y-4y. Each multiplexer also includes a select terminal 330, 332, respectively, and functions to transmit an a input to the corresponding output in the absence of a control input signal at the select terminal and to transmit the b input signal to the corresponding y output terminal when a select signal is present. The circuit of FIG. 7 also includes OR gates 304-308, AND gates 310-312 and OR gate 316 for determining the sequencing pattern by which signals are transmitted from the multiplexer 302 to bias on the transistors Q1-Q4 and, in turn, the Triacs 56-62. OR gates 318, 320, AND gate 322 and OR gate 324 serve to control the generation of the select signal to the select input terminal 330 of multiplexer 302 while OR gate 326 controls the generation of the select signal to the select terminal 332 of multiplexer 300. In this embodiment, the mode select switch S4 includes an on-off switch S4a and two nine-position switches, S4b and S4c, which serve, respectively, to select the reset point for the counter/decoder 82 and the enabling signals to the gates. This circuit further includes a zero crossing detector network comprised of transistors Q11 and Q12 which serve, through transistor Q13, to provide an enable signal to the enable input 15 of the multiplexer 302. The multiplexer 302 is designed such that an output is generated only if no enable signal is present. Thus, the zero crossing detector network serves to assure that the outputs of the multiplexer 302 are provided only at those points at which the AC power signal is at a zero crossing point to again minimize radio frequency interference that would otherwise be caused by the sequencing control circuit.
When operating in the mode 1 position of the switches S4b and S4c, the e output of the counter/decoder 82 furnishes the reset signal through the reset input 100 and enabling signals are provided to the gates 310-320 and 326. As no signal is supplied to the gate 320, AND gate 322 is not actuated and the select signal to multiplexer 302 is at zero level. Likewise, since the gate 326 is not energized, the select signal to the multiplexer 300 is at the zero level. Thus, each of the multiplexers outputs the a input to the corresponding y output. In this mode, the a output of the counter/decoder 82 is supplied through the 1y output of multiplexer 302 to OR gate 304 to bias on transistor Q1; the b output, through a similar path, to OR gate 306 to bias on transistor Q2; the c output, to OR gate 308 and transistor Q3; the d output, to transistor Q4. While the d output also provides an output at the 4y terminal of multiplexer 300, this output is not multiplexed through the multiplexer 302 since the b inputs are inactive at this time and, while OR gate 324 is enabled by the output of multiplexer 300, AND gate 322 is not enabled so that no output of this AND gate is generated. The mode 1 sequence is thus L1, L2, L3, L4 and repeat. The mode 2 sequence differs from the mode 1 sequence in that the reset signal is derived from the f output of the counter/decoder and in that the e output of counter/decoder 82 represents an off interval for the lights so that the sequence in the mode b operation is L1, L2, L3, L4, OFF and repeat. In the mode 3 position of the switches S4b and S4c the reset signal is again derived from the e output of the counter/decoder coder 82 but OR gate 316 is enabled to provide one enabling input to each of AND gates 310-314. As a consequence, the a output of the counter/decoder, through the 1y output of multiplexer 302, enables OR gate 304; the b output energizes OR gate 306 and AND gate 310 which, in turn, furnishes an enabling signal to OR gate 304; output c enables OR gate 308 and AND gate 302 which, in turn, enables OR gates 304 and 306; and output d biases on transistor Q4 and enables AND gate 314 to furnish enabling signals to OR gates 304, 306 and 308. The sequencing mode here is L1, L1L2, L1L2L3, L1L2L3L4 and repeat. The number 4 mode of operation is identical to that of mode 3 except that the reset signal to the counter/decoder 82 is again derived from the f output and the e output represents an off period thus providing a sequence of L1, L1L2, L1L2L3, L1L2L3L4, OFF and repeat. When the switches S4b and S4c are in the number 5 position the reset signal to counter/decoder is derived from the i output and both OR gates 316 and 318 are enabled. Enabling of the OR gate 318 also enables OR gate 320 to provide one enabling input to AND gate 322. The operation in this mode is identical to that of the two previously described modes for the first three outputs of the counter/decoder 82. The d output of the counter/decoder provides an input to the 4a input of the multiplexer 300 which furnishes an output at the 4y terminal of this multiplexer. The 4y output of the multiplexer 300 provides an input to OR gate 324 to enable this gate and provide a second enabling signal to AND gate 322. As a result, the select input of multiplexer 302 goes from the zero to the one state so that the b inputs of the multiplexer 302 are now transmitted to the 4y output of the multiplexer 302 and serves to bias on transistor Q4 and to provide a second enabling input to each of AND gates 310, 312 and 314 to, in turn, enable OR gates 304, 306 and 308, respectively. The e output of counter/decoder 82 is multiplexed through multiplexer 300 to the 3y output of this multiplexer and through the multiplexer 302 to the 3y output of this multiplexer thus providing an enabling signal to OR gate 308 and to AND gate 312 which, in turn, provides enabling signals to OR gates 306 and 308. The g output of counter/decoder 82 furnishes the 1y output of multiplexer 302 to enable gate 304. Since the h output of counter/decoder 82 provides only a b input to multiplexer 300 and the select signal input of this multiplexer is at the zero level, the h output of counter/decoder 82 represents an off period in the cycle. The sequencing mode provided here is L1, L1L2, L1L2L3, L1L2L3L4, L1L2L3, L1L2, L1, OFF and repeat.
The number 6 position of switches S4b and S4c provide for the g output of the counter/decoder 82 to function as the reset signal and provide an enabling signal to OR gate 318 and gate 320. The output sequence in this mode is L1, L2, L3, L4, L3, L2 and repeat.
The number 7 position of the switches S4b and S4c differs from the number 6 position only in the selection of the reset signal to the counter/decoder 82 and serves to provide an off period between the end of one sequence and the beginning of the repeating sequence.
In the number 8 position of the switches S4b and S4c, the i output of counter/decoder 82 produces the reset signal to this unit and OR gates 318 and 326 are enabled. Since OR gate 326 is enabled, the select input of multiplexer 300 is at the 1 level so that the a inputs to this multiplexer are ignored while the b inputs are connected to the corresponding y outputs. Since OR gate 316 is not actuated, no enabling signals are provided to the AND gates 310, 312 and 314. A sequence of L1, L2, L3, L4, OFF, L4, L3, L2 and repeat is provided by the number 8 position.
The number 9 position of the switches S4b and S4c differs from the 8 position in that gate 316 and gate 320 are enabled while gate 318 is not. Since gate 316 is enabled, enabling signals are provided to the AND gates 310, 312 and 314 to produce a sequence L1, L1L2, L1L2L3, L1L2L3L4, OFF, L1L2L3L4, L1L2L3, L1L2 and repeat.
While, in each of the sequencing circuit embodiments described above four output receptacles are provided and the sequences involve for lights or banks of lights, the invention is not limited to such an arrangement. Rather, the gating networks may be expanded as desired to control any number of outlets and any number of lights. Also, additional sequencing patterns may be provided by suitable rearrangement of the gating networks. It should also be understood that while specific circuit components have been identified, components of other manufacturers may be substituted. It is also contemplated that, while the disclosed circuits employ both integrated circuit and discreet circuit elements, the entire circuit is amenable to integrated circuit manufacture. As these and other changes and additions may be made to the disclosed embodiments, reference should be had to the appended claims in determining the true scope of the invention.
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A controller for sequentially energizing a plurality of lights, such as commercial display lighting or Christmas tree light strings, includes a plurality of outlet receptacles into which the lights or light strings may be connected, a Triac for each receptacle to control the energization thereof, a timing circuit and a programmable gating circuit responsive to the timing circuit and generating gating signals for the Triacs according to any of several predetermined sequential combinations.
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FIELD OF THE INVENTION
The invention relates to a shielding device for connection strips in telecommunications and data engineering, comprising a number of shielding plates and at least one base rail allocated to the latter.
BACKGROUND OF THE INVENTION
A shielding device of the generic type is already known from the connection strip disclosed in U.S. Pat. No. 5,160,273. Here, the problem of crosstalk between adjacent insulation-piercing terminal contact elements of the connection strip is solved by the insertion of a multiplicity of electrically conductive shielding plates between the individual pairs of insulation-piercing terminal contact elements. The problem of crosstalk occurs when transmitting large volumes of information via electrical lines, the information being transmitted at high frequencies. Transmitting at high frequencies produces radiation and interference between adjacent lines, particularly when these lines are arranged close beside one another in the connection strip. Electrically conductive shielding plates are inserted between a pair of insulation-piercing terminal contact elements, the spacing between two adjacent pairs of insulation-piercing terminal contact elements being larger than the spacing between adjacent insulation-piercing terminal contact elements in a pair. The shielding plates are in this case inserted between pairs of insulation-piercing terminal contact elements in slots which extend transversely to the longitudinal direction of the plastic body of the connection strip, and contact the base rail situated in the longitudinal direction inside the plastic body. A disadvantage of this is that, when fitting the component into the plastic body, it is first necessary to fit the base rail, which has contact tongues for contacting the individual shielding plates, and that it is subsequently necessary to push the individual shielding plates into the connection strip. Consequently, the complexity of assembly is relatively high in order to provide the connection strip with the shielding device for high transmission rates in telecommunications and data engineering.
SUMMARY AND OBJECTS OF THE INVENTION
The invention is therefore based on the object of improving the shielding device of the generic type in order to simplify assembly.
To achieve this object, the invention provides for the shielding plates and the base rail to be integrally formed from a metal plate, and for each shielding plate to be connected to the base rail via a narrow web and arranged rotated through approximately 90° with respect to the base rail. The shielding device according to the invention thus forms an integral component which is made of metallic material and which, during assembly of a connection strip for telecommunications and data engineering, is inserted into the plastic housing of the connection strip with its base rail, and its shielding plates, which are integrally connected to the base rail, are guided into all the preformed slots inside the connection strip at the same time. This simplifies assembly considerably.
In a further embodiment of the invention, the spacings between the shielding plates on a base rail may be designed to be different from one another. This enables a shielding plate to be matched to different applications.
The invention also relates to a method of producing the shielding device wherein a number of shielding plates and a base rail supporting the latter, as well as webs connecting the shielding plates to the base rail, are integrally formed from a metal sheet. The shielding plates are subsequently rotated in the region of the webs through approximately 90° with respect to the base rail.
According to a further aspect of the invention, a connection strip is provided for telecommunications and data engineering. The connection strip has insulation-piercing terminal contact elements arranged in a plastic housing, and shielding plates arranged between said insulation-piercing terminal contact elements. At least one ground rail is allocated to the shielding plates. The shielding plates and the base rail are integrally formed from a metal sheet. Each shielding plate is connected to the base rail via a narrow web and is arranged rotated through 90° with respect to the base rail.
According to still another aspect of the invention, a process for using a shielding device comprising a base rail and shielding plates is provided wherein the shielding plates are integrally formed on the base rail and are rotated through 90° with respect to the base rail. The device si used as a shielding inside a connection strip for high transmission rates in telecommunications and data engineering applications.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a perspective illustration of the shielding device;
FIG. 2 is a front view of the device of FIG. 1 ;
FIG. 3 is a plan view of the device of FIG. 1 ;
FIG. 4 is a plan view of a metal sheet having punched-out shielding plates and the base rail;
FIG. 5 is a perspective illustration, corresponding to FIG. 4 , of a part of the shielding device having a folded base rail;
FIG. 6 is a side view of a connection strip;
FIG. 7 is a cross sectional view along the line A—A in FIG. 6 ;
FIG. 8 is a plan view of the connection strip shown in FIG. 6 ; and
FIG. 9 is a cross sectional view along the line B—B in FIG. 8
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings in particular, in the exemplary embodiment, the shielding device 1 comprises seven flat, essentially U-shaped shielding plates 2 , a base rail 3 and seven connection webs 4 , which connect the individual shielding plates 2 to the base rail 3 . The shielding device 1 is made of conductive metallic material and is integrally formed, in particular punched, with the shielding plates 2 , the base rail 3 , and the connection webs 4 , from a metal sheet 28 . The sheet metal 28 is particularly copper, copper alloys, steel or aluminum. The shielding plates 2 and the base rail 3 with the connection webs 4 are initially in the same plane as the metal sheet 28 (as shown in FIG. 4 ). In a work step which follows the cutting-out process, the individual shielding plates 2 are rotated in the region of their 5 connection webs 4 through 90° with respect to the base rail 3 . A hole 5 in the base rail 3 is associated with each shielding plate 2 close to the connection web 4 , and this hole 5 is used for adjustment during the 4 production process. The metal sheet 28 may also be a metalized plastic strip or the like.
In the view of how the shielding device 1 is processed, shown in FIG. 4 , the individual shielding plates 2 are of U-shaped design, a roughly rectangular shielding panel 6 adjoining the connection web 4 and being provided with two prong-like shielding forks 7 at the end remote from the connection web 4 . These shielding forks 7 are stepped by means of a shoulder 8 which tapers the cross section so that they are matched to the internal cross section of the connection strip 11 .
FIG. 4 shows the metal sheet 28 with cut-out or punched-out shielding plates 2 of width B with a mean spacing X between one another and with the cut-out or punched-out base rail 3 with the holes 5 which are used for adjustment during production. The length of the metal sheet 28 corresponds to the number of shielding plates 2 of width B plus the cut gaps.
FIG. 5 shows the shielding plates 2 which are rotated through 90° with respect to the base rail 3 and are normally at a distance X from one another. To achieve a shorter distance X′, a fold 9 is introduced into the base rail 3 , as shown in FIG. 8 .
The shielding device 1 is used for shielding the individual insulation-piercing terminal contact elements 10 inside a connection strip 11 for high transmission rates in telecommunications and data engineering. Such a connection strip 11 , having a plurality of insulation-piercing terminal contact elements 10 arranged in pairs, is illustrated and described in more detail in DE 43 25 952 C2 (and in U.S. Pat. No. 5,494,461). U.S. Pat. No. 5,494,461 is hereby incorporated by reference. The connection strip 11 is illustrated in FIGS. 6 to 9 and is described in more detail below with respect to the shielding device 1 used.
The connection strip 11 comprises a plastic housing 12 made of an upper part 13 and a lower part 14 which are latched to one another by means of latching openings 15 in the upper part 13 and latching lugs 16 in the lower part 14 . Terminal slots 17 are formed in the upper part 13 and have integrally formed terminal lugs 18 and terminal webs 19 which serve to hold the insulation-piercing terminal contact elements 10 . The latter are formed from sheet-like flat material and comprise two contact webs 21 enclosing a contact slot 20 between them. A base web 22 is adjoined by contact fingers 23 which merge into spring contacts 24 . Two pairs of insulation-piercing terminal contact elements 10 are respectively arranged close beside one another, the spacing D between two adjacent pairs of insulation-piercing terminal contact elements 10 being considerably larger than the spacing d between insulation-piercing terminal contact elements 10 which are close beside one another, as can be seen in FIG. 6 . The individual shielding plates 2 of the shielding device 1 are inserted into the total of seven wider cross-sectional regions 25 of the connection strip 11 , as shown by dashed lines in FIGS. 6 and 7 and by solid lines in FIGS. 8 and 9 .
To insert the base rail 3 with the individual shielding plates 2 into the housing 12 of the connection strip 11 , the upper part 13 in the exemplary embodiment contains seven chambers 26 with respective transverse slots 27 into which the individual shielding plates 2 are pushed. The base rail 3 is situated in a longitudinal slot 21 in the bottom region of the lower part 14 , as shown in FIGS. 7 and 9 . The shielding panels 6 and shielding forks 7 , which adjoin the latter, of the individual shielding plates 2 essentially take up the whole of the cross section of the interior of the connection strip 11 , as shown in FIG. 9 in particular, and thus separate the individual pairs of insulation-piercing terminal contact elements 10 in such a manner that greater 5 crosstalk attenuation is achieved for high transmission rates as a result of the electrically conductive shielding plates 2 . The use of the large-area electrically conductive shielding plates 2 in the connection strip 11 does not require the physical volume of the connection strip to be enlarged, nor any greater expense to produce it.
The shielding device 1 does not require any grounding. It is important only that the individual shielding plates 2 are conductively connected to one another. This is achieved by means of the base rail 3 , which is common to all the shielding plates 2 . The shielding plates 2 influence the electrical field in such a way that the influence charging of an insulation-piercing terminal contact element 10 is reduced in the adjacent insulation-piercing terminal contact element 10 , and the interference voltage is thus small. This produces a relatively high signal-to-noise ratio. The signal-to-noise ratio becomes higher, with the result that higher frequencies can be transmitted without the adjacent lines of the insulation-piercing terminal contact elements 10 having an adverse effect on one another.
The number of shielding plates 2 in a shielding device 1 depends on the number of pairs of insulation-piercing terminal contact elements 10 . In the exemplary embodiment, an 8-pair module is illustrated, which has seven chambers 26 for a total of seven shielding plates 2 . Common pairings are 4/3, 8/7, 10/9, 12/11, 16/15, 20/19, 24/23 and 25/24, where the number of pairs of insulation-piercing terminal contact elements 10 and the number of shielding plates 2 are indicated in each case.
For a HIGHBAND® brand 8 connection strip 11 , the standard spacing X between the shielding plates 2 is X=12.6 mm. However, for a HIGHBAND® brand 10 connection strip 11 , for example, the spacing is X′=9.6 mm. For this, the folds 9 are introduced into the base rail 3 between each of the individual shielding plates 2 . This spacing cannot be achieved by directly punching the shielding device 1 out of a metal sheet 28 , since the width B of the individual shielding plate 2 needs to be around 12 mm on account of the width of the connection strip 11 . Hence, for a HIGHBAND® brand 8 connection strip 11 , 10 the dimensions width B=12.6 mm and spacing X=12.6 mm complement one another well. For a narrower spacing X′, however, folds 9 are necessary; these may be replaced by any other kind of means for shortening the length of the base rail 3 .
While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.
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A shielding device for connection strips in telecommunications and data engineering has a number of shielding plates and at least one base rail allocated to the shielding plates. To simplify the process of fitting the shielding device inside a connection strip, the shielding plates ( 2 ) and the base rail ( 3 ) are integrally formed from a metal sheet ( 28 ), and each shielding plate ( 2 ) is connected to the base rail ( 3 ) via a narrow web ( 4 ) and is arranged rotated through approximately 90° with respect to the base rail ( 3 ).
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/242,112, entitled, “REPOSITIONABLE PIT SEAL,” filed Sep. 14, 2009.
RELATED ART
[0002] 1. Field of the Invention
[0003] The present invention is directed to a novel art, repositionable pit seals for shipping dock pits originally designed to accommodate horizontally stored dock levelers, but retrofitted to accommodate vertically stored dock levelers.
[0004] 2. Brief Discussion of Related Art
[0005] Referring to FIG. 1 , Vertical Storing Dock Levelers (VSDLs) 10 are commonly hydraulically operated dock levelers that provide a generally horizontal gangway between the floor 12 of a building and the floor of a transport vehicle (i.e., a truck or tractor trailer) in order to load and unload goods between the building and the transport vehicle. As the name indicates, VSDLs 10 are stored vertically, in contrast to the horizontal use position, and allow the recessed floor 14 of the building to which the VSDL is mounted to be accessible for clean-up purposes.
[0006] In circumstances where a building is designed to accommodate VSDLs 10 , a two-tiered or stair-stepped building floor is poured. The first, upper tier floor 12 is the primary floor of the building and is generally level across the vast majority of the building. But the second tier floor or bottom floor 14 is vertically lower than the upper tier floor by approximately 10-12 inches. This second tier floor 14 is substantially level and commonly extends across the entire side of the building where one or more loading docks are located. The opening of each loading dock may be closed off exclusively by an overhead door.
[0007] Consistent with the foregoing reference system, C-channel track for the overhead door (not shown) may extend to the surface of the second tier floor 14 . The overhead door vertically and horizontally spans the entire loading dock opening when in a lowered position. This lowered position corresponds to the bottom of the overhead door abutting the top surface of the second tier floor 14 to substantially prevent air loss gaps and access for vermin entry. In other words, the overhead door extends vertically below the horizontal surface of the first tier floor 12 .
[0008] Referencing FIG. 2 , in circumstances where a building is designed to accommodate horizontally stored dock levelers 22 , individual rectangular pits 16 are formed into the concrete floor to accommodate each dock leveler. The walls of the pit 16 partially define a cubic rectangular cavity and include a right side wall 18 , a left side wall 20 , a rear wall, and a floor 24 . In some cases, the pit walls 18 , 20 , 24 are lined with a metal insert. Nevertheless, horizontally stored dock levelers 22 are repositionable to change the pitch of the gangway or dock floor to accommodate loading heights higher and lower than the building floor.
[0009] Conventional horizontally stored dock levelers 22 include a top surface or deck that is generally level with that of the building floor surrounding the pit 16 when the dock leveler is not in use. As a result of this horizontal storage position, conventional overhead doors contact the gangway of the dock leveler 22 so that both the overhead door and dock leveler block the opening of the dock. In other words, the overhead doors do not close off the portion of the loading dock opening partially occupied by the dock leveler. This also means that the C-channel guides for the overhead doors only extend to the building floor, which is elevated with respect to the pit floor. Thus, any gap between the top of the dock leveler (gangway) and the pit floor cannot be closed off by an overhead door. Because gaps between the dock leveler 22 and pit 16 cannot be sealed by the overhead door, these gaps allow airflow therethrough, as well as access for vermin. Because of these problems, many buildings designed to use horizontally stored dock levelers 22 have been retrofit to accommodate VSDLs 10 . But this retrofitting comes at a considerable price.
[0010] Retrofitting costs to convert a building previously using horizontally stored dock levelers 22 to VSDLs 10 are substantial. First, the vertical storage orientation of the VSDLs 10 requires the overhead door to close off the entire dock opening. In order to accommodate an overhead door that goes beyond the primary building floor and extends into the pit 16 , concrete must be removed on both sides of the pit below the location of the old C-channel overhead door guides. Thereafter, new C-channel is installed that extends into the floor of the expanded pit 16 . In addition, at least one new section must be added to the overhead door to provide the increased vertical length necessary to close off the opening. Alternatively, an entirely new overhead door may be installed. Not only are the direct costs associated with retrofitting expensive, but so too are the indirect costs associated with losing access to a loading dock until the retrofitting is complete.
INTRODUCTION TO THE INVENTION
[0011] The instant disclosure provides an alternative to conventional retrofitting of buildings to accommodate VSDLs 10 . In particular the instant disclosure provides a more cost effective alternative by substantially lessening expenses and down time to switch a loading dock from the horizontally stored dock leveler 22 to a VSDL 10 . Of particular importance, the instant disclosure allows building owners to maintain their existing overhead doors, track, and floor. Instead of cutting out portions of the building floor to bring the overhead door to the floor, as is the case in the prior art, the instant disclosure is operative to bring the floor to the door or bring the door to the floor without changing the dimensions of the floor. Specifically, the vertical depth and width at the front of a conventional pit is closed off using a repositionable pit seal. This repositionable pit seal may be mounted to the pit floor or to the overhead door in order to close off the vertical depth and width of the pit when the VSDL 10 is in its vertical storage position. However, when the VSDL 10 is in its horizontal use position, the repositionable pit seal is moved out of the way of the VSDL. The repositionable pit seal may be automatically or manually repositioned by the actuation of the overhead door, the actuation of the VSDL 10 , or an independent device. The repositionable pit seal is operative to reduce drafts through the front opening of the pit and allows buildings having dock leveler pits to be retrofit without expanding the pit or replacing the preexisting overhead door.
[0012] It is a first aspect of the present invention to provide a method of selectively closing off a loading dock opening defined by a loading dock pit recessed within a floor of a building and a doorway into the building, the method comprising: (a) repositioning a pit seal panel having a substantially incompressible height and width to a barrier position where the pit seal panel closes off a rectangular area substantially spanning an entire vertical dimension and an entire widthwise dimension of the loading dock pit; and (b) lowering an overhead door to concurrently contact the pit seal panel and the floor of the building to close off the loading dock opening.
[0013] In a more detailed embodiment of the first aspect, the method further includes repositioning a vertically stored dock leveler from a horizontal use position to a vertical storage position prior, the vertically stored dock leveler at least partially located within the loading dock pit, wherein repositioning the vertically stored dock leveler from the horizontal use position to the vertical storage position coincides with repositioning the pit seal panel to the barrier position. In yet another more detailed embodiment, a mechanical linkage is concurrently mounted to the vertical stored dock leveler and the pit seal panel so that repositioning the vertically stored dock leveler to from the horizontal use position to the vertical storage position is operative to reposition the pit seal panel to the barrier position. In a further detailed embodiment, the act of repositioning the pit seal panel includes controlling the repositioning of the pit seal panel with an electronic controller that receives information regarding the position of the vertically stored dock leveler. In still a further detailed embodiment, the pit seal panel is mounted to an interior wall partially defining the loading dock pit, and the act of repositioning the pit seal panel to the barrier position includes pivoting the pit seal panel with respect to the interior wall of the loading dock pit.
[0014] In yet another more detailed embodiment of the first aspect, the pit seal panel is mounted to the overhead door, and the act of repositioning the pit seal panel to the barrier position includes repositioning the pit seal panel with respect to the overhead door and lowering the pit seal panel into the loading dock pit. In still another more detailed embodiment, the pit seal panel is pivotally mounted to the overhead door, and an actuator is concurrently mounted to the pit seal panel and the overhead door to reposition the pit seal panel to the barrier position. In a further detailed embodiment, a top of the pit seal panel engages a bottom of the overhead door when the bottom of the overhead door contacts the top of the pit seal panel to lock the pit seal panel to the overhead door. In still a further detailed embodiment, the method further includes repositioning the pit seal panel from the barrier position to a storage position, and raising an overhead door to discontinue contact with the floor of the building, where raising the overhead door and repositioning the pit seal panel to the storage position is operative to no longer close off the loading dock opening. In a more detailed embodiment, further comprising the act of lowering the overhead door to concurrently contact the pit seal panel and the floor of the building is operative to lock the pit seal panel in the barrier position.
[0015] It is a second aspect of the present invention to provide a method of repositioning a rigid wall to selectively blockade a forward area of a loading dock pit formed into the floor of a building and partially defined by opposing vertical side walls, a rear vertical wall, and a bottom horizontal surface, the loading dock pit including a rear area, opposite the forward aspect, at least partially occupied by a vertically stored dock leveler, the method comprising: (a) positioning a rigid wall to a blocking position within the forward aspect of the loading dock pit, the blocking position having the rigid wall horizontally spanning between the opposing vertical side walls and concurrently vertically spanning between the bottom horizontal surface and a horizontal plane of the floor of the building; and (b) positioning an overhead door to concurrently contact the rigid wall and the floor of the building to lock the rigid wall in the blocking position.
[0016] In a more detailed embodiment of the second aspect, the method further comprises repositioning the rigid wall from the blocking position to a storage position so the rigid wall does not concurrently horizontally span between the opposing vertical side walls and vertically span between the bottom horizontal surface and the horizontal plane of the floor of the building, and repositioning the overhead door to no longer concurrently contact the rigid wall and the floor of the building, and positioning the vertically stored dock leveler from a vertical storage position to a horizontal use position so that a decking of the vertically stored dock leveler is generally parallel to the floor of the building, where the vertical storage position is not reached prior to repositioning the rigid wall from the blocking position. In yet another more detailed embodiment, the method further comprising the act of positioning the vertically stored dock leveler to a vertical storage position so that a decking of the vertically stored dock leveler is generally perpendicular to the floor of the building, wherein a mechanical linkage is concurrently mounted to the vertical stored dock leveler and the rigid wall so that positioning the vertically stored dock leveler to the vertical storage position is operative to position the rigid wall to the blocking position. In a further detailed embodiment, the act of repositioning the rigid wall from the blocking position to the storage position includes controlling the repositioning of the rigid wall with an electronic controller that receives information regarding the position of the vertically stored dock leveler.
[0017] In yet another more detailed embodiment of the second aspect, the rigid wall is mounted to at least one of the opposing vertical side walls and the bottom horizontal surface partially defining the loading dock pit, and the act of positioning the rigid wall to the blocking position includes pivoting the rigid wall with respect to at least one of the opposing vertical side walls and the bottom horizontal surface of the loading dock pit. In still another more detailed embodiment, the method further comprises positioning the vertically stored dock leveler from a vertical storage position to a horizontal use position so that a decking of the vertically stored dock leveler is generally parallel to the floor of the building, and the act of pivoting the rigid wall with respect to at least one of the opposing vertical side walls of the loading dock pit includes pivoting the rigid wall to be beneath the vertically stored dock leveler when the vertically stored dock leveler is in the horizontal use position. In a further detailed embodiment, the method further comprises repositioning the rigid wall from the blocking position to a storage position by lifting the rigid wall out of the loading dock pit, wherein the rigid wall is removably mounted to at least one of the opposing vertical side walls and the bottom horizontal surface partially defining the loading dock pit. In still a further detailed embodiment, the rigid wall is mounted to the overhead door, and the act of positioning the rigid wall to the blocking position includes positioning the rigid wall with respect to the overhead door and lowering the rigid wall into the forward aspect of the loading dock pit. In a more detailed embodiment, a top of the rigid wall locks into a bottom of the overhead door when the bottom of the overhead door contacts the top of the rigid barrier. In a more detailed embodiment, the method further comprises repositioning the vertically stored dock leveler from a vertical storage position to a horizontal use position, repositioning the rigid wall from a blocking position to a storage position beneath the horizontal use position of the vertically stored dock leveler, and where the rigid wall is biased to the blocking position, and where the act of repositioning the vertically stored dock leveler from a vertical storage position to a horizontal use position includes the vertically stored dock leveler contacting a roller mounted to rigid wall to overcome the bias of the rigid wall and reposition the rigid wall to the storage position.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a perspective view of a vertical stored dock leveler, showing the underneath surface of the dock leveler.
[0019] FIG. 2 is an elevated perspective view of a horizontally stored dock leveler, shown in its fully raised position.
[0020] FIG. 3 is an elevated, isolated perspective view of a convention loading dock pit, with an overhead door in the closed position.
[0021] FIG. 4 is an elevated perspective view of an exemplary repositionable pit seal mounted within a conventional loading dock pit, where the pit seal is shown in its vertical deployed position and where the overhead door is shown in its closed position.
[0022] FIG. 5 a perspective view of a vertical stored dock leveler mounted within a conventional loading dock pit and stored in its vertical storage position.
[0023] FIG. 6 are cross-sectional views of mounting brackets for use with an exemplary embodiment of the disclosure.
[0024] FIG. 7 is a cross-sectional view of an exemplary pit seal panel in accordance with an exemplary embodiment of the disclosure.
[0025] FIG. 8 is an isolated, perspective view of a top corner of a pit seal panel in accordance with an exemplary embodiment of the disclosure.
[0026] FIG. 9 is a cross-sectional view of weather-stripping for use with the exemplary embodiments of the disclosure.
[0027] FIG. 10 is a cross-sectional view of further weather-stripping for use with the exemplary embodiments of the disclosure.
[0028] FIG. 11 is a profile view of an exemplary pit seal in accordance with the disclosure.
[0029] FIG. 12 is a profile view of an exemplary pit seal of FIG. 11 , shown in initial engagement with a lowered vertically stored dock leveler.
[0030] FIG. 13 is a profile view of an exemplary pit seal of FIG. 11 , shown in engagement with a lowered vertically stored dock leveler, where the dock leveler is lowered more than shown in FIG. 12 .
[0031] FIG. 14 is a profile view of an exemplary pit seal of FIG. 11 , shown in engagement with a lowered vertically stored dock leveler, where the dock leveler is lowered more than shown in FIG. 13 .
[0032] FIG. 15 is a profile view of an exemplary pit seal of FIG. 11 , shown in engagement with a lowered vertically stored dock leveler, where the dock leveler is lowered more than shown in FIG. 14 .
[0033] FIG. 16 is a profile view of the left side of an exemplary pit having an exemplary pit seal installed and mounted to a vertically stored dock leveler.
[0034] FIG. 17 is a frontal view of the exemplary pit seal of FIG. 16 installed and mounted to a vertically stored dock leveler.
[0035] FIG. 18 is a profile view of the mechanical linkage between the exemplary pit seal of FIG. 16 and a vertically stored dock leveler.
[0036] FIG. 19 is a profile view of the mechanical linkage of FIG. 18 when the vertically stored dock leveler is lowered beyond that shown in FIG. 18 .
[0037] FIG. 20 is a profile view of the mechanical linkage of FIG. 18 when the vertically stored dock leveler is lowered beyond that shown in FIG. 19 .
[0038] FIG. 21 is a profile view of the mechanical linkage of FIG. 18 when the vertically stored dock leveler is lowered beyond that shown in FIG. 20 .
[0039] FIG. 22 is a profile view of an alternate mechanical linkage between the exemplary pit seal and a vertically stored dock leveler when the dock leveler is positioned in its vertical storage position.
[0040] FIG. 23 is a profile view of an alternate mechanical linkage of FIG. 22 showing the position of the between the exemplary pit seal of FIG. 23 and a vertically stored dock leveler when the dock leveler is lowered to its horizontal use position.
[0041] FIG. 24 is a rear view of an exemplary pit seal mounted to a conventional overhead door, where the pit seal is shown in its vertical barrier position and where the overhead door is shown in its closed position.
[0042] FIG. 25 is a cross-sectional view of the exemplary pit seal panel, weather-stripping retainer, and weather-stripping comprising a part of the exemplary pit seal of FIG. 24 .
[0043] FIG. 26 is a rear view of the exemplary pit seal of FIG. 24 , where the pit seal is pivoted with respect to the overhead door when the overhead door is in its open position.
DETAILED DESCRIPTION
[0044] The exemplary embodiments of the present disclosure are described and illustrated below to encompass repositionable pit doors for dock leveler pits. Of course, it will be apparent to those of ordinary skill in the art that the embodiments discussed below are exemplary in nature and may be reconfigured without departing from the scope and spirit of the present invention. However, for clarity and precision, the exemplary embodiments as discussed below may include optional steps, methods, and features that one of ordinary skill should recognize as not being a requisite to fall within the scope of the present invention.
[0045] Referencing FIGS. 3 and 4 , an exemplary loading dock 100 includes a pit 102 formed within a floor 112 of a warehouse or other loading/unloading facility that previously accommodated a horizontally stored dock leveler. The pit includes right 104 , left 106 , and rear 108 walls, in addition to a recessed (with respect to the warehouse floor 112 ) horizontal floor 110 . The warehouse floor 112 adjacent the right and left walls 104 , 106 has embedded therein a C-track 114 that receives rollers 116 (shown in phantom) mounted to an overhead door 118 (shown in phantom). In this exemplary embodiment, the overhead door 118 is retained in its native form just as it was with the conventional, horizontally stored dock leveler.
[0046] Referring to FIGS. 4 and 5 , the retrofitting includes replacing a horizontally stored dock leveler with a vertical stored dock leveler (VSDL) 120 (not shown in FIG. 4 ), which is mounted to the pit 102 proximate the rear wall 108 . Proximate the front of the pit 102 , opposite the rear wall 108 is a repositionable pit door 122 . This repositionable pit door 122 has vertical dimensions approximating the depth of the pit 102 and lateral dimensions approximating the width of the pit.
[0047] Referencing FIGS. 3 , 4 , 6 and 7 , the base of the pit door 122 is pivotally mounted to the floor 110 of the pit 102 . Two 90° angle brackets 125 are mounted to the right and left walls 104 , 106 of the pit 102 so that the corner 127 of each bracket fits within a corresponding corner formed by the interface of the right/left wall 104 , 106 with the pit floor 110 . Each bracket 125 includes a dowel 129 that extends perpendicularly outward from the left/right wall 104 , 106 . The dowel 129 is seated within a key-shaped opening 134 that longitudinally extends across a lower portion of the extruded plastic pit seal panel 123 . As will be discussed in more detail hereafter, the pit door 122 is removably mounted to the dowels 129 in order to allow removal of the pit door 122 when the VSDL 120 is vertically stored, so as to allow easier cleaning of the pit 102 .
[0048] Referring to FIG. 7 , the pit door 122 includes an extruded pit panel 123 having a generally planar front vertical wall 126 spaced apart from a generally planar rear vertical wall 128 by a plurality of linear, longitudinal ribs 130 . Some of the longitudinal ribs 130 extend normally between the front and rear walls 126 , 128 , while other ribs 130 extend between the front and rear walls 126 , 128 at obtuse or acute angles. The longitudinal ribs 130 are spaced apart from one another so that longitudinal voids 131 are formed that are generally bounded by adjacent ribs 130 and the front and rear vertical walls 126 , 128 . The longitudinal ribs 130 are operative to retard substantial deformation of the front and rear walls 126 , 128 when horizontal contact forces are applied to the walls 126 , 128 . At the same time, the longitudinal ribs 130 are operative to function as a structural support for the front and rear walls 126 , 128 so these walls 126 , 128 are operative to support vertical loads. At the bottom of the panel 123 , longitudinally extending in parallel to the longitudinal ribs 130 , is a key-shaped opening 134 . This key-shaped opening 134 defines a key-shaped rib 136 having opposed tapering surfaces 138 that intersect with a semi-circular surface 140 . The semi-circular surface 140 defines a substantially cylindrical cavity into which the dowels 129 of the angle brackets 125 are received. A pair of detents 142 are formed at the intersection of the tapering surfaces 138 and the semi-circular surface 140 in order to allow the panel 123 to be selectively removed from the dowels 129 and thereafter allow the panel 123 to receive the dowels 129 and thereby selectively reattach the panel 123 to the dowels. Opposite the key-shaped rib 136 is a generally planar top surface 143 , where the top surface 143 and the key-shaped rib 136 sandwich the longitudinal ribs 130 therebetween. In this exemplary embodiment, the lateral/longitudinal ends of the panel 123 remain open. In addition, it is also within the scope of the invention to at least partially fill some or all the voids 131 with insulation. Exemplary forms of insulation include, without limitation, polystyrene foams, polyethylene foams, and latex foams.
[0049] Referring to FIG. 8 , a keeper 150 is mounted to both the front and rear faces 126 , 128 proximate the top surface 143 of the panel 123 . In this exemplary embodiment, the keeper 150 comprises a section of angled ¼″ aluminum sheet that is bent at a 35-degree angle to comprise two substantially planar sections 152 , 154 . The first planar sections 152 of each keeper 150 includes a pair of holes receiving fasteners 158 to mount the keepers 150 to the walls 126 , 128 of the panel 123 proximate the top surface 143 . It should be understood that the panel 123 includes corresponding through holes (not shown) that are aligned with the through holes of the keepers 150 to accept the fasteners 158 . Exemplary fasteners 158 for mounting the keepers 150 include, without limitation, nuts and bolts. Mounting the keepers 150 to the panel 123 creates a tapered opening above the top surface 143 . Accordingly, as will be discussed in more detail hereafter, the keepers 150 are operative to provide a tolerance and finder system for an overhead door to ensure that when the overhead door is lowered onto the panel 123 , the bottom of the overhead door is longitudinally aligned and seated upon the top 143 of the panel.
[0050] Referring back to FIG. 7 , in this exemplary embodiment, an aluminum cap 170 is seated upon the top surface 143 and similar aluminum caps (not shown) are seated on the lateral/longitudinal sides of the panel 123 . The aluminum caps 170 extend substantially the entire length on top of the panel and aluminum caps extend substantially the entire height of the panel on each side. Each cap 170 comprises a base surface 174 and a pair of perpendicularly extending legs 175 that collectively define an opening having a rectangular cross-section. This rectangular cross-section approximates the rectangular cross-section of the panel 123 so that the front and rear walls 126 , 128 of the panel 123 are compression fit within the opening of the cap 170 . Those skilled in the art will realize that the caps 170 may be mounted to the panels 123 using other techniques such as, without limitation, adhesives or mechanical fasteners. In addition, those skilled in the art will realize that the legs 175 of each cap 170 are tapered at 45-degree angles (shown as angle “A”) in order so that the horizontal and vertical caps 170 to abut one another at the corners of the panel 123 .
[0051] Referring to FIGS. 7 and 9 , opposite the rectangular opening of each cap 170 is a pair of inverted T-shaped cavities 178 defined by corresponding prongs 176 . Each cavity 178 is adapted to receive a corresponding T-shaped projection 180 that extends from a rubber, domed seal 182 . In this manner, the T-shaped projections 180 of the rubber seal 182 (i.e., weatherstripping) are longitudinally fed into the respective inverted T-shaped cavities 178 to mount the seal 182 to the cap 170 so that the seal extends substantially along the entire length of the cap. As will be discussed in more detail hereafter, the domed seal 182 on top of the panel 123 is sandwiched between the panel and the bottom of an overhead door to substantially inhibit air flow between the bottom of the overhead door and the top of the panel 123 . At the same time, the domed seal 182 on both lateral ends of the panel 123 is sandwiched between the panel and the side walls 126 , 128 of the pit.
[0052] Alternatively, referring to FIGS. 7 and 10 , the caps 170 on the lateral ends of the panel 123 may only include a single inverted T-shaped cavity 178 to receive a corresponding T-shaped projection 190 that extends from rubber weather stripping 192 . In this manner, the T-shaped projection 190 of the weather stripping 192 is longitudinally fed into the respective inverted T-shaped cavity 178 to mount the weather stripping 192 to the cap 170 so that the weather stripping extends along the entire length of the cap. In this manner, the weather stripping 192 on the sides of the panel 123 contacts the right and left side walls 104 , 106 of the pit 102 to substantially inhibit airflow between the walls 104 , 106 and the panel 123 .
[0053] Repositioner #1
[0054] Referencing FIG. 11 , the repositionable pit door 122 may optionally include an exemplary repositioning device selectively engaged by the VSDL 120 to reposition the panel 123 between a vertical deployment position and a horizontal or near horizontal storage position. Each repositioning device includes at least one engagement device 234 mounted to the interior face 128 of the panel 123 . The engagement device 234 is operative to contact the VSDL 120 so that as the VSDL is lowered, the engagement device overcomes the bias of springs, such as leaf springs 232 , mounted to the pit seal panel 123 . When the panel 123 is in its default upright barrier position (see FIG. 11 ), the leaf springs 232 provide a bias to maintain the panel in its vertical orientation.
[0055] Each engagement device 234 includes a pair or rollers 236 mounted to opposite ends of an arcuately shaped bracket 238 . In this exemplary embodiment, each roller 236 is freely rotatable with respect to the bracket 238 in order to accommodate a rolling motion against the underside of the VSDL 120 . The bracket 238 includes a through hole that is adapted to receive a pin 244 that also extends through a clevis 242 at one end of an extension 246 . In this manner, the arcuate bracket 238 is operable to pivot with respect to the extension 246 about the pin 244 . As will be discussed in more detail below, pivoting occurs during raising and lowering of the panel 123 as the rollers 236 contact the underside of the VSDL 120 . Finally, the end of the extension 246 opposite the clevis 242 is mounted to the interior surface 128 of the panel 123 using conventional fasteners, such as bolts (not shown).
[0056] As discussed previously, the top of the panel 123 includes the domed seal 182 that is adapted to be correspondingly received within a concave cavity 252 on the bottom of a conventional overhead door 218 . However, it is also within the scope of the disclosure that the bottom of the overhead door 218 be planar or exhibit a convex shape. Regardless of the shape of the bottom of the overhead door 218 , the domed seal 182 closes off gaps between the overhead door 218 and the panel 123 when the overhead door is lowered and the panel 123 is vertically oriented. In exemplary form, many overhead doors 218 have weather-stripping mounted to the bottom in order to form a seal with the ground. Thus, it may be advantageous to remove the weather-stripping from the bottom of the overhead door 218 to form an appropriate connection with the domed seal 182 of the panel 123 .
[0057] Referencing FIG. 12-15 , when the VSDL 120 is repositioned from its vertical storage position to its horizontal use position, the pit seal 122 is also repositioned so as not to interfere with operation of the VSDL 120 . In operation, as the VSDL 120 is pivoted from its vertical storage position to a horizontal or near horizontal use position, the underside of the VSDL 120 initially contacts the top roller 236 mounted to the arcuate bracket 238 (see FIG. 12 ). Continued downward movement of the VSDL 120 against the top roller 236 causes the arcuate bracket 238 to pivot with respect to the extension 246 , about the pin 244 , until the bottom roller 236 contacts the underside of the VSDL 120 (see FIG. 13 ). At this point, the panel 123 remains in its vertical barrier position. But further downward movement of the VSDL 120 against the rollers 236 is operative to push the arcuate bracket 238 downward and correspondingly pivot the bracket 238 about the pin 244 with respect to the extension 246 until the clevis 242 limits the pivoting.
[0058] Referring to FIGS. 14 and 15 , continued downward movement of the VSDL 120 causes the rollers 236 to roll against the underside of the VSDL toward the pivot point of the VSDL. At the same time, the binding of the clevis 242 against the arcuate bracket 238 pulls the top of the panel 123 rearward toward the pivot point of the VSDL (see FIG. 14 ). But because the panel 123 is pivotally mounted at the bottom to the dowels 129 , this rearward pulling action is converted into a pivoting action that causes the panel to move from a vertical barrier position toward a horizontal or near horizontal storage position under the VSDL 120 . This pivoting action, caused by direct contact with the VSDL 120 , is operative to overcome the bias of the leaf springs 232 and allow the panel 123 to be pivoted rearwardly. Continued downward movement of the VSDL 120 to approximate its horizontal use position corresponds with the rollers 236 continuing their rolling contact the underside of the VSDL to reach a position that most closely approximates the VSDL pivot point of any position the rollers occupy while in contact with the VSDL. This same rearward most position of the rollers 236 also corresponds to the maximum pivoting or deflection of the panel 123 so that the panel reaches its horizontal or near horizontal storage position (see FIG. 15 ). An opposite sequence when raising the VSDL 120 to its vertical storage position allows the panel 123 to return to its vertical barrier position, in part, using the bias of the leaf springs 232 .
[0059] Referring back to FIG. 15 , as the VSDL 120 is raised to its vertical storage position, the pit seal 122 also returns to its default vertical barrier position. In exemplary form, as the VSDL 120 is pivoted upward (compare FIG. 15 with FIG. 14 ), the rollers 136 roll against the underside of the VSDL 120 . This is caused by the bias of the leaf springs 232 against the rear of the panel 123 , which correspondingly forces the panel 123 , extension 246 , and bracket 238 upward. Further upward pivoting movement of the VSDL 120 is accompanied by pivoting of the pit seal 122 until both rollers 236 are no longer in contact with the underside of the VSDL 120 , which corresponds with the panel 123 arriving at its vertical barrier position. At this point, only the top roller 236 remains engaged and thus the bottom roller 236 of the bracket 238 pivots toward the interior surface 128 of the panel 123 . Ultimately, the top roller 136 looses contact with the underside of the VSDL 120 as the VSDL is pivoted to more closely approximate its vertical storage position.
[0060] Referring back to FIGS. 4 and 11 , after the VSDL 120 has cleared the top roller 236 and approximates its vertical storage position, the overhead door 118 , 218 may be lowered to close off the loading dock 100 opening. In exemplary form, the overhead door 118 , 218 is lowered so that its bottom engages the top surface of the pit seal panel 123 to close off the loading dock 100 opening. When a conventional panel overhead door 118 , 218 is fully lowered, the door may be locked in its fully lowered position by repositioning a slide mounted to one of the door panels so that the slide engage an opening (not shown) in the a C-track 114 . Those skilled in the art are familiar with overhead door locks and a further explanation has been omitted for purposes of brevity. When the overhead door 118 , 218 is in its fully lowered position on top of the pit seal panel 123 , the pit seal panel 123 cannot be pivoted. As a result, locking the overhead door 118 , 218 in its fully lowered position is likewise operative to lock the pit seal panel 123 in its vertical barrier position.
[0061] It is also within the scope of the invention for the bottom panel of the overhead door 118 , 218 and/or the pit seal 122 to include fasteners to lock the bottom panel of the overhead door to the pit seal panel 123 . In the alternative, the bottom panel of the overhead door 118 , 218 and/or the pit seal panel 123 may include dowels that engage corresponding cavities in the opposite structure in order to prohibit the pit seal panel 123 from pivoting inward toward the VSDL when the overhead door 118 , 218 is fully lowered to contact the top of the pit seal panel 123 , specifically the weatherstripping 182 .
[0062] While the foregoing embodiment has been described with the pit seal 122 being spring biased toward the vertical position so that contact with the VSDL 120 overcomes the spring bias to reposition the pit seal to its nearly horizontal storage position, it is also within the scope of the invention to include a mechanical linkage between the VSDL 120 and the pit seal 122 to pivot the panel 123 downward as the VSDL is pivoted downward, and vice versa.
[0063] Referring to FIGS. 16 and 17 , a mechanical linkage 300 is operative to reposition the pit seal 122 between its barrier and storage positions. The VSDL 120 is repositionable between a vertical storage position and a horizontal use position. Structurally, the VSDL 120 includes a plurality of structural braces 320 that extend linearly underneath decking 304 , which provides a working surface when the VSDL is in its horizontal use position. A pair of outermost flanges 306 extend perpendicularly from an edge of the decking 304 and underneath the decking. These outermost flanges 306 are inset within the pit 102 when the VSDL 120 is in its horizontal use position. At the same time, one of the outermost flanges 306 includes a through hole that receives a bolt 310 of the mechanical linkage 300 to physically connect the VSDL to the pit seal 122 .
[0064] An exemplary mechanical linkage 300 includes an arcuate, right angled bracket 314 fabricated from quarter-inch bar stock. One end of the bracket 314 includes a through hole that receives the bolt 310 concurrently extending through one of the outermost flanges 306 in order to mount the bracket to the flange. An opposite end of the bracket 314 also includes a through hole receiving a ball of a ball joint coupling 318 . The ball of the ball joint coupling 318 is secured to the bracket 314 using a conventional nut (not shown). A complementary half of the ball joint coupling 318 includes a threaded control arm 316 which is mounted to a threaded cylindrical tube 324 at an opposite end. Another end of the cylindrical tube 324 is welded to a section of bar stock 330 having a circular opening (not shown) formed at an end opposite the cylindrical tube 324 . This circular opening receives a cylindrical pin 334 that is mounted to a right angle bracket 336 . This right angle bracket 336 is mounted to the front wall 126 of the repositionable panel 123 . In this exemplary embodiment, the pin 334 extends slightly laterally beyond the panel 123 just enough to extend through the circular opening of the bar stock 330 . The end of the pin 334 that extends beyond the bar stock 330 may include a linchpin or some other means to maintain the pin 334 within the opening in the bar stock 330 as the VSDL 120 is repositioned between its horizontal use position and its vertical storage position.
[0065] Referring to FIGS. 18-21 , an exemplary sequence of repositioning the pit seal 122 from its vertical barrier position to its near horizontal storage position begins with raising any overhead door out of the line of travel of the VSDL 120 . Thereafter, the VSDL 120 is pivoted proximate the rear of the pit (see FIG. 16 ) so that the decking goes from a vertical storage position (see FIG. 18 ) to a horizontal use position (see FIG. 21 ). During the pivoting of the VSDL 120 , the mechanical linkage 300 concurrently attached to the panel 123 and the VSDL 120 is operative to transfer the downward pivoting motion of the VSDL into downward pivoting motion of the panel. In other words, as the VSDL 120 is pivoted downward, from vertical to horizontal, so too are the outermost flanges 306 . Also, because the one of the flanges 306 is rigidly mounted to the bracket 314 , pivotal movement of the flange also results in pivotal movement of the bracket. The arcuate nature of the bracket 314 works with the arcuate path of the bolt 310 to convert the arcuate motion of the VSDL 120 into horizontal pulling motion on the threaded control arm 316 , the threaded cylindrical tube 324 , and the bar stock 330 . This horizontal pulling motion of the bar stock 330 is transferred to the panel 123 by way of the pin 334 and the right angle bracket 336 . Because the bottom of the panel 123 is pivotally mounted to the floor of the pit, horizontal movement at the top of the panel 123 is converted into pivotal motion of the entire panel 123 . The sequence of motion to reposition the pit seal panel 123 from a vertical barrier position to a near horizontal storage position is shown by a series of snapshots as depicted in FIGS. 18-21 . Conversely, raising the pit seal panel 123 from its storage position to its barrier position occurs as the VSDL 120 is pivoted from a horizontal to a vertical storage position. While the foregoing exemplary embodiment has used a solid mechanical linkage, other forms of linkage may be utilized to reposition the pit seal panel 123 responsive to motion of the VSDL 120 .
[0066] Referring now to FIGS. 22 and 23 , in exemplary form, the pit seal panel 123 may be spring biased using a torsion spring 350 mounted concurrently to the panel and to the pit wall. In this exemplary embodiment, the panel 123 is biased toward its vertical barrier position. However, a cable 356 is concurrently mounted to the VSDL 120 and the panel 123 using separate pulleys 352 , 354 . Each of the pulleys 352 , 354 is rigidly attached to either the VSDL 120 or the panel 123 so that pivoting motion of the VSDL 120 and panel 123 is correspondingly transferred to the respective pulley as rotational motion, and vice versa. In this fashion, as the VSDL 120 is pivoted downward from its vertical storage position and toward its horizontal use position, the pulley 352 mounted to the VSDL is rotated in a clockwise fashion. This clockwise rotation is operative to pull on the cable 356 toward the first pulley 352 and away from the second pulley 354 . As a result, the cable 356 necessarily transfers the clockwise rotation of the first pulley 352 into counterclockwise rotation of the second pulley 354 . This counterclockwise motion of the second pulley 354 causes the panel 123 to pivot rearward toward the VSDL 120 , which is resisted by the torsion spring 350 . But the force on the cable 356 is large enough to overcome the spring bias exerted by the torsion spring 350 , thereby repositioning the panel 123 . In this manner, continued rotation of the first pulley 352 from the pivoting of the VSDL 120 is operative to continue pulling on the cable 356 and continue rotating the second pulley 354 until the VSDL reaches its horizontal use position (see FIG. 23 ).
[0067] It is also within the scope of the disclosure to include a servo motor (not shown) coupled to the first pulley 352 or the second pulley 354 instead of the VSDL 120 . A feedback control sensor (not shown) would detect downward and upward pivoting motion of the VSDL and cause the servo motor to rotate the pulley(s) 352 , 354 clockwise or counterclockwise to raise or lower the panel 123 . In exemplary form, the sensor may be tied into the control panel of the VSDL 120 to directly sense instructions to the hydraulic motors of the VSDL 120 and respond appropriately with the correct servo motor motion in order to properly position the panel 123 between a vertical barrier position and a near horizontal storage position. Those skilled in the art are familiar with control panels for VSDLs and a detailed discussion of this feature has been omitted only for purposes of brevity.
[0068] Repositioner #2
[0069] Referring to FIGS. 24-26 , a further exemplary repositionable pit seal 400 , in contrast to the foregoing exemplary embodiments, is repositionably mounted to the bottom of a conventional overhead door 402 . In this exemplary embodiment, the repositionable pit seal 400 comprises a pit seal panel 404 that is pivotally mounted to the bottom panel of an overhead door 402 via a pair of hinges 406 .
[0070] As shown in FIG. 25 , the construction of the pit seal panel 404 is similar to the pit seal panel 123 of the foregoing exemplary embodiments. Specifically, the pit seal panel 404 may be fabricated from an extruded polymer or metal and includes a generally planar front face sheet 408 and rear face sheet 410 . The front face sheet 408 is adapted to face outward, away from interior of the building housing the pit 102 , while the rear face sheet 410 is adapted to face the interior of the building. The face sheets 408 , 410 are interposed by a series of walls 412 that extend longitudinally along the length of the panel 404 . As can be seen from FIG. 25 , these walls 412 are angled at various degrees to provide structural support to the face sheets 408 , 410 . Together, the walls 412 , and face sheets 408 , 410 define a series of longitudinal cavities 414 extending through the panel 404 . Depending upon the end application, such as in a refrigerated building, the cavities may include an insulating material such as, without limitation, latex or acrylic foam.
[0071] The top 416 and bottom 418 of the panel 404 are substantially flat and have mounted thereto a weather-strip retainer 420 having a pair of inverted T-shaped cavities. These inverted T-shaped cavities are adapted to receive the corresponding T-shaped ends of weather-stripping 422 to secure the weather-stripping to the weather-strip retainer 420 . At least one opening (not shown) is formed through the bottom 418 of the panel 404 , the weather-stripping retainer 420 , and the weather-stripping 422 in order to accommodate throughput of at least one retainer pin 424 .
[0072] In this exemplary embodiment, two retainer pins 424 are mounted within corresponding openings in the floor 110 of the pit 102 . The retainer pins 424 operate to inhibit lateral movement of the lower portion of the panel 404 when the pins 424 are secured within the openings 426 in the panel. In exemplary form, the panel 404 also includes weather-stripping retainers 420 and weather-stripping 422 along the lateral/longitudinal sides, thereby forming a weather-stripping perimeter around the panel.
[0073] Alternatively, or in addition to utilizing the retainer pins 424 , the pit 102 may include a pair of tapered or U-shaped guides 430 to precisely guide the panel 404 into position as the panel is lowered into the pit 102 and into its barrier position. Each guide 430 is bolted to the floor 110 of the pit 102 and is positioned adjacent to the right and left side walls 104 , 106 . Accordingly, any attempt to dislodge or laterally remove the panel 404 from outside is inoperative because the guides 430 and pins 424 cooperate to retain the panel 404 laterally in position. With that said, the panel 404 may be not be repositioned vertically if the overhead door 402 is locked in its furthermost lowered position. Yet when the overhead door 402 is raised, so too is the panel 404 raised. However, in order to maintain the vertical clearance of the original overhead door 402 , the panel 404 is selectively repositionable.
[0074] The exemplary repositionable pit seal 400 includes a pneumatic cylinder or linear actuator 440 concurrently mounted to the overhead door 402 and the pit seal panel 404 . A pair of angle brackets 442 are vertically oriented and mounted to the overhead door 402 in a spaced apart fashion. Each of the angle brackets includes a plurality of through holes that are adapted to receive a rod 444 to secure the cylinder end of the pneumatic cylinder 440 . The opposite end of the pneumatic cylinder 440 is mounted to the panel 404 using a rod 446 and a pair of angle brackets 448 . The angle brackets 448 mounted to the panel 404 are vertically oriented and spaced apart to accommodate the piston of the pneumatic cylinder 440 . Again, similar to the brackets 442 mounted to the overhead door, the brackets 448 mounted to the panel 404 include a series of vertically distributed through holes to accommodate different throughput locations of the rod 446 .
[0075] In operation, the repositionable pit seal 400 may be repositioned between a barrier position (see FIG. 24 ) and an egress position (see FIG. 26 ). By way of exemplary explanation, repositioning the pit seal 400 from its barrier position to its egress position includes unlocking the overhead door 402 from the adjacent C-track 114 . Presuming the overhead door 402 , and the rollers 116 mounted thereto, are able to be repositioned with respect to the C-track, the overhead door may be raised using a conventional overhead door lift system (not shown). As the overhead door 402 is raised, so too is the pit seal 400 . As the pit seal panel 404 is vertically raised, the lateral ends to the panel initially follow the track of the guides 430 and allow the panel to be raised vertically over the pins 424 . As soon as the panel 424 clears the pins 424 and guides 430 , the pneumatic cylinder or linear actuator 440 may be engaged to pivot the panel with respect to the overhead door 402 .
[0076] By way of example, the pneumatic cylinder or linear actuator 440 allows the panel 424 to be pivoted anywhere between 0-135 degrees (either inward or outward) with respect to the overhead door. As shown in FIG. 26 , the panel 424 is pivoted outward approximately 90 degrees from the bottom section of the overhead door 402 . In this position, the clearance otherwise obtainable by the overhead door 402 prior to attaching the panel is nearly the same as that achieved when the panel is pivoted 90 degrees with respect to the overhead door. However, those skilled in the art will understand that pneumatic cylinder or linear actuator 440 is optional as it may not be necessary to pivot the panel with respect to the door such as circumstances where clearance is not an issue. In exemplary form, the pneumatic cylinder or linear actuator 440 includes an electronic controller (not shown) and other appropriate sensors and electronics as will be known to those skilled in the art and programmed to reposition the panel 404 as the overhead door 402 is repositioned.
[0077] Repositioning the pit seal 400 to its barrier position includes a similar sequence of events performed in reverse order. For example, as the overhead door 402 is initially lowered from its overhead storage position, the panel 404 is pivoted to be vertically aligned with the overhead door, the guides 430 , and the pins 424 . After the panel 404 is vertically aligned with the door 402 , the door may be further lowered so that the bottom of the door reaches the floor 117 of the building. As the overhead door 402 reaches the floor 117 of the building, the lower portion of the panel 404 is positioned adjacent to the floor 110 of the pit 102 . Thus, the combination of the panel 404 and overhead door 402 is operative to close off the entire loading dock opening.
[0078] Following from the above description and invention summaries, it should be apparent to those of ordinary skill in the art that, while the methods and apparatuses herein described constitute exemplary embodiments of the present invention, the invention contained herein is not limited to this precise embodiment and that changes may be made to such embodiments without departing from the scope of the invention as defined by the claims. Additionally, it is to be understood that the invention is defined by the claims and it is not intended that any limitations or elements describing the exemplary embodiments set forth herein are to be incorporated into the interpretation of any claim element unless such limitation or element is explicitly stated. Likewise, it is to be understood that it is not necessary to meet any or all of the identified advantages or objects of the invention disclosed herein in order to fall within the scope of any claims, since the invention is defined by the claims and since inherent and/or unforeseen advantages of the present invention may exist even though they may not have been explicitly discussed herein.
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A method of selectively closing off a loading dock opening defined by a loading dock pit recessed within a floor of a building and a doorway into the building, the method comprising: (a) repositioning a pit seal panel having a substantially incompressible height and width to a barrier position where the pit seal panel closes off a rectangular area substantially spanning an entire vertical dimension and an entire widthwise dimension of the loading dock pit; and (b) lowering an overhead door to concurrently contact the pit seal panel and the floor of the building to close off the loading dock opening.
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TECHNICAL FIELD OF THE INVENTION
[0001] The present invention is generally directed to systems and methods for evaluating video quality, and, in particular, to an improved system and method for providing a scalable dynamic objective metric for automatically evaluating video quality of a video image.
BACKGROUND OF THE INVENTION
[0002] Video experts continually seek new algorithms and methods for improving the quality of video images. The primary goal is to obtain the most perceptually appealing video image possible. The ultimate criterion is the question “How well does the viewer like the resulting picture?” One way to answer the question is to have a panel of viewers watch certain video sequences and then record the opinions of the viewers concerning the resulting image quality. The results, however, will vary from panel to panel according to the variability between the viewing panels. This problem is commonly encountered when relying on subjective human opinion. The severity of the problem is increased when the viewing panel is composed of non-experts.
[0003] Results solely based upon on human perception and subjective opinion are usually subjected to subsequent statistical analysis to remove ambiguities that result from the non-deterministic nature of subjective results. Linear and non-linear heuristic statistical models have been proposed to normalize these types of subjective results and obtain certain figures of merit that represent the goodness (or the degradation) of video quality. The process of measuring video quality in this manner is referred to as “subjective video quality assessment.”
[0004] Subjective video quality assessment methods give valid indications of visible video artifacts. Subjective video quality assessment methods, however, are probabilistic in nature, complex, time consuming, and sometimes difficult to apply. In addition, there is a problem in selecting appropriate viewers for the viewing panel. A non-trained viewer will be a poor judge of the suitability of new video processing methods. A non-trained viewer, however, will likely accurately represent the general consumers in the marketplace. On the other hand, a trained expert viewer will be overly biased toward detecting minor defects that will never be noticed by the general consumer.
[0005] To avoid the disadvantages that attend subjective methods for evaluating video quality, it is desirable to use automated objective methods to evaluate video quality. Automated objective methods seek to obtain objective figure of merits to quantify the goodness (or the degradation) of video quality. The process for obtaining one or more objective measures of the video quality must be automated in order to be able to quickly analyze differing types of video algorithms as the video algorithms sequentially appear in a video stream.
[0006] Objective measures of video quality are fully deterministic. That is, the results will always be the same when the test is repeated (assuming the same settings are preserved).
[0007] Because the ultimate goal is to present the viewer with the most appealing picture, a final judge of the value of the objective measures of video quality is the degree of correlation that the objective measures have with the subjective results. Statistical analysis is usually used to correlate the results objectively obtained (automatically generated) with the results subjectively obtained (from human opinion).
[0008] There is a need in the art for improved systems and methods for automatically measuring video quality. The process of automatically measuring video quality is referred to as “objective video quality assessment.”
[0009] Several different types of algorithms have been proposed that are capable of providing objective video quality assessment. The algorithms are generally referred to as “objective video quality models.” A report from the Video Quality Experts Group (VQEG) sets forth and describes the results of an evaluation performed on ten (10) objective video quality models. The report is dated December 1999 and is entitled “Final Report from the Video Quality Experts Group on the validation of Objective Models of Video Quality Assessment.” The report is presently available on the World Wide Web at http://www.crc.ca/VQEG.
[0010] Each different objective video quality model provides its own distinctive measurement of video quality referred to as an “objective metric.” A “double ended” objective metric is one that evaluates video quality using a first original video image and a second processed video image. A “double ended” objective metric compares the first original video image to the second processed video image to evaluate video quality by determining changes in the original video image. A “single ended” objective metric is one that evaluates video quality without referring to the original video image. A “single ended” objective metric” applies an algorithm to a video image to evaluate its quality.
[0011] No single objective metric has been found to be superior to all the other objective metrics under all conditions and for all video artifacts. Each objective metric has its own advantages and disadvantages. Objective metrics differ widely in performance (i.e., how well their results correlate with subjective quality assessment results), and in stability (i.e., how well they handle different types of video artifacts), and in complexity (i.e., how much computation power is needed to perform the algorithm calculations).
[0012] A wide range of applications exist to which objective metrics may be applied. For example, fast real-time objective metrics are needed to judge the quality of a broadcast video signal. On the other hand, more complex and reliable objective metrics are better for judging the quality of non-real time video simulations.
[0013] Using only one objective metric (and one objective video quality model) limits the evaluation of the quality of a video signal to the level of evaluation that is obtainable from the objective metric that is used. There is a need in the art for an improved system and method that uses more than one objective metric for video quality evaluation.
SUMMARY OF THE INVENTION
[0014] The present invention generally comprises an improved system and method for providing a scalable dynamic objective metric for automatically evaluating video quality of a video image.
[0015] In an advantageous embodiment of the present invention, the improved system of the invention comprises an objective metric controller that is capable of receiving a plurality of objective metric figures of merit from a plurality of objective metric model units. The objective metric controller is capable of determining a scalable dynamic objective metric from the plurality of objective figures of merit.
[0016] In an advantageous embodiment of the present invention, the improved method of the invention comprises the steps of 1) receiving in an objective metric controller a plurality of objective metric figures of merit from a plurality of objective metric model units, and 2) determining a scalable dynamic objective metric from the plurality of said objective metric figures of merit.
[0017] It is a primary object of the present invention to provide an improved system and method for providing a scalable dynamic objective metric for automatically evaluating video quality of a video image.
[0018] It is another object of the present invention to provide a scalable dynamic objective metric by obtaining a weighted average of a plurality of objective metric figures of merit.
[0019] It is an additional object of the present invention to provide a scalable dynamic objective metric by obtaining a weighted average of a plurality of objective metric figures of merit using a correlation factor that represents how well an objective metric figure of merit evaluates video image characteristics.
[0020] It is another object of the present invention to continually determine new values of the scalable dynamic objective metric from new values of the plurality of objective metric figures of merit as new video images are continually received.
[0021] The foregoing has outlined rather broadly the features and technical advantages of the present invention so that those skilled in the art may better understand the Detailed Description of the Invention that follows. Additional features and advantages of the invention will be described hereinafter that form the subject of the claims of the invention. Those skilled in the art should appreciate that they may readily use the conception and the specific embodiment disclosed as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the invention in its broadest form.
[0022] Before undertaking the Detailed Description of the Invention, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms “include” and “comprise” and derivatives thereof, mean inclusion without limitation; the term “or,” is inclusive, meaning and/or; the phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like; and the term “controller,” “processor,” or “apparatus” means any device, system or part thereof that controls at least one operation, such a device may be implemented in hardware, firmware or software, or some combination of at least two of the same. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, wherein like numbers designate like objects, and in which:
[0024] [0024]FIG. 1 is a block diagram that illustrates 1) a plurality of objective metric model units for obtaining a plurality of objective metric figures of merit from a video stream and 2) a objective metric controller capable of using the plurality of objective metric figures of merit to determine a scalable dynamic objective metric; and
[0025] [0025]FIG. 2 is a flow chart diagram illustrating an advantageous method of operation of the improved system of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0026] [0026]FIGS. 1 and 2, discussed below, and the various embodiments set forth in this patent document to describe the principles of the improved system and method of the present invention are by way of illustration only and should not be construed in any way to limit the scope of the invention. Those skilled in the art will readily understand that the principles of the present invention may also be successfully applied in any type of device for evaluating video quality.
[0027] [0027]FIG. 1 illustrates system 100 for providing a scalable dynamic objective metric for automatic video quality evaluation. System 100 receives video stream 110 . Each of a plurality of objective metric model units ( 120 , 130 , . . . , 140 ) receives a copy of the video signal of video stream 110 . Objective metric model unit 120 applies a first objective metric model (referred to as “Metric 1 ”) to obtain a first figure of merit, f( 1 ), that represents the quality of the video signal based on the first objective metric model. The first figure of merit, f( 1 ), is provided to controller 150 .
[0028] Similarly, objective metric model unit 130 applies a second objective metric model (referred to as “Metric 2 ”) to obtain a second figure of merit, f( 2 ), that represents the quality of the video signal based on the second objective metric model. The second figure of merit, f( 2 ), is also provided to controller 150 . Continuing in this manner, other objective metric model units are added until the last objective metric model unit 140 has been added. Objective metric model unit 140 applies the last objective metric model (referred to as “Metric N”). Objective metric model units ( 120 , 130 , . . . , 140 ) obtain a plurality of figures of merit (f( 1 ), f( 2 ), . . . , f(N)) and provide them to controller 150 .
[0029] The figures of merit (f( 1 ), f( 2 ), . . . , f(N)) represent a series of N evaluations of the quality of the video stream by N different objective metrics. The figures of merit (f( 1 ), f( 2 ), . . . , f(N)) may also be designated f(i) where the value of i goes from 1 to N.
[0030] As will be explained below in greater detail, system 100 of the present invention provides a system and method for using the figures of merit f(i) to calculate a scalable dynamic objective metric. The letter “F” (shown in FIG. 1) designates the scalable dynamic objective metric of the present invention.
[0031] System 100 of the present invention comprises controller 150 and memory 160 . Controller 150 comprises a conventional microprocessor chip. Controller 150 is coupled to a plurality of objective metric model units ( 120 , 130 , . . . , 140 ) via signal communication lines (shown in FIG. 1). Controller 150 operates in conjunction with an operating system (not shown) located within memory 160 to process data, to store data, to retrieve data and to output data. Controller 150 calculates scalable dynamic objective metric “F” by executing computer instructions stored in memory 160 .
[0032] Memory 160 may comprise random access memory (RAM), read only memory (ROM), or a combination of random access memory (RAM) and read only memory (ROM). In an advantageous embodiment of the present invention, memory 160 may comprise a non-volatile random access memory (RAM), such as flash memory. Memory 160 may also comprise a mass storage data device, such as a hard disk drive (not shown in FIG. 1) or a compact disk read only memory (CD-ROM) (not shown in FIG. 1).
[0033] It is noted that the system and method of the present invention may be used in a wide variety of types of video processing systems, including, without limitation, hard disk drive based television sets and hard disk drive based video recorders, such as a ReplayTV™ video recorder or a TiVO™ video recorder.
[0034] Controller 150 and metric calculation algorithm 170 together comprise an objective metric controller that is capable of carrying out the present invention. Under the direction of computer instructions in metric calculation algorithm 170 stored within memory 160 , controller 150 calculates a scalable dynamic objective metric “F” using the figures of merit f(i).
[0035] A weighting unit 190 within controller 150 dynamically detects the currently occurring characteristics of the video sequence. The currently occurring characteristics may include such features as sharpness, color, saturation, motion, and similar types of features. Weighting unit 190 assigns a value (or “weight”) w(i) to each objective metric (Metric 1 , Metric 2 , . . . , Metric N). For example, if Metric 1 is especially good when used on a certain first type of video signal, then the value of w( 1 ) is given a greater value than the other values of w(i). Conversely, if Metric 2 is not very good when used on that same first type of video signal, then w( 2 ) will be given a lower value than the other values of w(i). If a second type of video signal is present, it may be that Metric 1 is not as good as Metric 2 when used on the second type of video signal. In that case, w( 2 ) is given a higher value and w( 1 ) is given a lower value than the other values of w(i).
[0036] Generally speaking, the values of w(i) that weighting unit 190 selects will vary depending upon the type of video signal that weighing unit 190 dynamically detects. Controller 150 uses metric calculation algorithm 170 to calculate the sum S of the products of each w(i) and f(i). That is,
S=w ( 1 ) f ( 1 )+ w ( 2 ) f ( 2 )+ . . . + w ( N ) f ( N ) (1)
or S=Σw ( i ) f ( i ) (2)
[0037] where the value of i runs from 1 to N.
[0038] A correlation factor r(i) is associated with each figure of merit f(i). The correlation factor r(i) is obtained from the expression:
r ( i )=1−[ A ( i )/ B] (3)
[0039] where
A ( i )=6Σ[( X ( i,j )− Y ( i,j )] 2 (4)
[0040] where the value of j runs from 1 to n.
[0041] and where
B=n ( n 2 −1) (5)
[0042] The values of X(i,j) are the values of a set of n objective data values for a video image. The values of Y(i,j) are the values of a set of n subjective data values for the same video image. That is, the number of X data points (n) is the same number of Y data points (n).
[0043] The value r(i) is referred to as the “Spearman rank” correlation factor. The value r(i) is a measure of how well the objective X values match the subjective Y values. The values of the correlations factors r(i) for each figure of merit f(i) are known, having been previously determined by statistical analysis. Values of the correlation factors r(i) are stored in metric parameters look up table 180 in memory 150 .
[0044] A “best fitting” value for scalable dynamic objective metric “F” is desired. The “best fitting” value of “F” represents the highest level of correlation of the objective metric measurements of video quality (generated automatically) and the subjective measurements of video quality (from human opinions). The “best fitting” value of “F” represents the closest approximation of the subjective measurements of video quality by the objective measurements of video quality. Because the video images in a video stream are constantly changing, the “best fit” will require constant automatic updating. The term “dynamic” refers to the ability of the objective metric of the present invention to continually change its value to take into account the continual changes of the video images in a video stream.
[0045] As previously mentioned, weighting unit 190 continually (i.e., dynamically) detects the characteristics of the video sequence as they occur. For each correlation factor r(i), weighting unit 190 continually assigns values of w(i)-to each figure of merit f(i). To dynamically obtain the “best fitting” value of “F”, metric calculation algorithm 170 determines the values of w(i) that cause the value S to be a maximum for each value of r(i). The largest of these values (i.e., the maximum value) is selected to be the scalable dynamic objective metric “F.” That is,
F =Maximum [ S ( r ( 1 )), S ( r ( 2 )), . . . , S ( r ( N ))] (6)
[0046] Scalable dynamic objective metric “F” is referred to as “scalable” because new objective metric model units can be easily added (as long as their correlation factors r(i) are defined). In addition, objective metric model units that are no longer desired can easily be removed.
[0047] The scalable dynamic objective metric “F” of the present invention provides a great deal of flexibility. For example, for fast (real time) video signals, any complicated measurement objective metrics may be switched off so that their figures of merit are not considered in the metric calculation process. For simulation and video chain optimization applications, where more time can be used to perform the metric calculation, the more complicated measurement objective metrics may be switched on so that their figures of merit may be considered in the metric calculation process.
[0048] The scalable dynamic objective metric of the present invention avoids the shortcomings of any single objective metric. This is because weighting unit 190 will assign a low value to w(i) for any objective metric that performs poorly in the presence of a certain set of artifacts. The scalable dynamic objective metric of the present invention achieves the highest correlation with the results of subjective testing when compared any single objective metric. The scalable dynamic objective metric of the present invention will be at least as good as the best single objective metric under all circumstances. Because the scalable dynamic objective metric permits the inclusion of any objective metric, the system and method of the present invention is not limited to use with a particular type of objective metric (e.g., a “single ended” objective metric or a “double ended” objective metric).
[0049] It is noted that the elements of the present invention that have been implemented in software (e.g., weighting unit 190 ) may be implemented in hardware if so desired.
[0050] [0050]FIG. 2 is a flow chart diagram illustrating the method of operation of the system of the present invention. The steps of the method are generally denoted with reference numeral 200 . A video image from video stream 110 is provided to N objective metric model units ( 120 , 130 , . . . , 140 ). The N objective metric model units ( 120 , 130 , . . . , 140 ) evaluate the video image and obtain N respective figures of merit, f(i) (step 205 ).
[0051] Weighting unit 190 in objective metric controller 150 then dynamically detects video characteristics of the video image and assigns N weights, w(i), to the N figures of merit, f(i) (step 210 ). For each correlation factor, r(i), objective metric controller 150 calculates a sum, S(r(i)), that is equal to the sum of each product of weight, w(i), and figure of merit, f(i) (step 215 ).
[0052] Objective metric controller 150 then selects the maximum value of the sum, S(r(i)), that corresponds to the best correlation of objective measurements of video quality with subjective measurements of video quality (step 220 ). Objective metric controller 150 then assigns that value to be the value of the scalable dynamic objective metric “F” (step 225 ). Objective metric controller 150 then outputs that value of “F” (step 230 ).
[0053] After the value of “F” has been output, a determination is made whether objective metric controller 150 is still receiving video images (decision step 235 ). If the video has ended, then the process ends. If the video has not ended and more video images are being received, control passes back to step 205 and the objective controller 150 continues to operate in the manner that has been described.
[0054] The present invention has been described as a system for providing a scalable dynamic objective metric for evaluating video quality of a video image. It is understood that the “scalable dynamic objective metric” of the present invention is a general case that includes as a subset the more specific case of providing a “static objective metric.” To provide a “static objective metric” the present invention 1) receives a plurality of objective metric figures of merit from a plurality of objective metric model units, and 2) determines a weight value, w(i), for each of the plurality of objective metric figures of merit, and 3) thereafter keeps the weight values, w(i), constant (i.e., unchanged) during the process of calculating objective metric “F” for video stream 110 .
[0055] Although the present invention has been described in detail, those skilled in the art should understand that they can make various changes, substitutions and alterations herein without departing from the spirit and scope of the invention in its broadest form.
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There is disclosed an improved system and method for providing a scalable dynamic objective metric for automatically evaluating the video quality of a video image. The system comprises an objective metric controller that is capable of receiving a plurality of objective metric figures of merit from a plurality of objective metric model units. The system determines a scalable dynamic objective metric from a weighted average of the plurality of objective metric figures of merit. The scalable dynamic objective metric represents the best correlation of objective metric measurements of the video image with subjective measurements of the video image. The weight value of individual objective metric figures of merit may be increased or decreased depending upon the type of video image being evaluated. Individual objective metric figures of merit may be added to the system or deleted from the system. The system is capable of continually determining a new value of the scalable dynamic objective metric as the plurality of objective metric model units receive new video images.
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FIELD OF THE INVENTION
The present invention relates to an image display apparatus controlling image quality of displayed images, in which the control is triggered by power-on, according to an audio-visual environment of a user and the only thing the user has to do for suitable image quality control is to answer simple inquiries.
BACKGROUND ART
Generally, when the user watches images displayed on the display apparatus, there is a deficiency that the image displayed on the display becomes less-visible depending on the audio-visual environment such as ambient brightness and distance between the user and the display apparatus. In order to solve the above deficiency, for example, the patent reference 1 discloses a display apparatus, in which control of image quality is carried out by inputting weather, light intensity, and viewing position etc.
Patent reference 1: Unexamined Japanese Patent Publication No. 2007-43533
DISCLOSURE OF THE INVENTION
Problems that the Invention Tries to Solve
Generally, adjustment of image quality of the display is carried out while viewing the display. For example, when the ambient brightness is high while viewing the display, the luminance or contrast of the display is appropriately enhanced, or when a child views the display, in order to reduce stimulus, the luminance or contrast of the display is appropriately reduced. However, for the elderly or a user who is not familiar with appliances, in many cases, they cannot easily adjust image quality. Therefore, even if the luminance or contrast of the display is too high or too low, many of such users give up on the adjustment.
In addition, generally, the image quality of display is adjusted, therefore, its brightness and contrast is enhanced before shipment from a factory, so that it looks better at the shop. In this case, although the image quality is suitable for viewing at the shop, when viewing in a home, its brightness and contrast may be too high. Then, the user does the adjustment of the image quality in order to reduce the luminance or contrast etc. However, the user who is not familiar with appliances cannot do the adjustment of image quality and cannot help but to view the display with unnecessarily high brightness. Here, a system for easily and semi-automatically selecting the image quality is demanded by the user.
In addition, in the display apparatus of the patent reference 1, setting of image quality is carried out by directly inputting weather (light intensity), current time, and viewing position etc. Additionally, for example, weather-related information is automatically acquired from an FM multiple signal transmitted from VICS (Vehicle Information and Communication System), however, if the power of an audio apparatus is off, it is impossible to receive the information. Additionally, it is disclosed that the user inputs such information, however, it is too complicated and bothersome for the user to input them when they deem it appropriate.
Means for Solving the Problems
In an aspect of the present invention, an image display apparatus stores information for forming inquiry relating to an audio-visual environment and option information selected as an answer in response to the inquiry formed on the basis of the information for forming inquiry, and stores a plurality of image quality control rules suitable for the audio-visual environment expected according to the option information as the answer. In addition, the image display apparatus outputs the inquiry on the basis of the information for forming inquiry stored in the storage for inquiry, in which the output is triggered by detection of the power-on, and acquires result information, which is an option as the answer from a user and is to be utilized for acquiring the image quality control rule, acquires the image quality control rule from the storage for image quality control rules according to the result information, and the image quality control is carried out according to the acquired image quality control rule.
FIG. 1 is a conceptual diagram showing operations of an image display apparatus of the present invention. When the power-on of the image display apparatus is done ( 0101 ), the inquiries relating to the audio-visual environment are outputted ( 0102 ) to the user. These inquiries relating to the audio-visual environment are simple inquires ( 0103 ), for example, inquiries about usages of the image display apparatus. Additionally, options for the inquires are preliminarily provided, and the image quality control rules suitable for the audio-visual environment expected corresponding to the respective options ( 0104 , 0105 , 0106 , and 0107 ) are preliminarily determined. Therefore, when the user of the image display apparatus answers to the simple inquiries related to the audio-visual environment, the predetermined image quality control rule is determined according to the answer, thereby carrying out the image quality control in accordance with the determined image quality control rule. Accordingly, the only thing the user has to do for suitable image quality control is to answer the simple inquiries upon the power-on of the image display apparatus.
In another aspect of the present invention, a processing to acquire the image may be executed only when the power-on is done upon installation of the apparatus. In another aspect of the present invention, display size information as the result information may be acquired. In another aspect of the present invention, the image quality control rule may be changed. In another aspect of the present invention, the image quality control may be changed. In another aspect of the present invention, the image quality control may include any one or more than one of luminance control, luminance modulation characteristics control, color density control, or sharpness control. In another aspect of the present invention, a result of the acquisition of the image quality control rule may be displayed.
Effects of the Invention
In the image display apparatus of the present invention, simple inquires relating to the audio-visual environment are outputted when the power-on is detected, and the only thing the user has to do for suitable image quality control is to answer the simple inquiries, thereby improving user-friendliness.
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described hereinbelow with reference to the drawings. The present invention is not to be limited to the above embodiments and able to be embodied in various forms without departing from the scope thereof. A first embodiment will mainly describe Claims 1 , 6 , 8 , and 10 to 12 . A second embodiment will mainly describe Claims 2 and 13 . A third embodiment will mainly describe Claim 3 , A fourth embodiment will mainly describe Claim 4 . A fifth embodiment will mainly describe Claim 5 . A sixth embodiment will mainly describe Claim 7 . A seventh embodiment will mainly describe Claim 9 .
<<First Embodiment>>
<Concept of First Embodiment>
In a first embodiment, an image display apparatus stores information for forming inquiry relating to an audio-visual environment and option information selected as an answer in response to the inquiry formed on the basis of the information for forming inquiry, and stores a plurality of image quality control rules suitable for the audio-visual environment expected according to the option information as the answer. In addition, the image display apparatus outputs the inquiry on the basis of the information for forming inquiry stored in the storage for inquiry, in which the output is triggered by detection of the power-on, and acquires result information, which is an option as the answer from a user and is to be utilized for acquiring the image quality control rule, acquires the image quality control rule from the storage for image quality control rules according to the result information, and the image quality control is carried out according to the acquired image quality control rule.
<Configuration of First Embodiment>
FIG. 2 is a functional block diagram of the image display apparatus of the first embodiment.
An image display apparatus ( 0200 ) comprises a ‘storage for inquiry’ ( 0201 ), a ‘storage for image quality control rules’ ( 0202 ), a ‘first acquirer’ ( 0203 ), an ‘acquirer for image quality control rule’ ( 0204 ), an ‘image quality controller’ ( 0205 ), a ‘power-on detector’ ( 0206 ), and a ‘setting controller’ ( 0207 ).
Note that the respective units of the present invention can be configured by hardware, software, or both hardware and software. For example, in the case of using a computer, the respective units are implemented by the hardware configured by a CPU, a memory, a bus, an interface, and other peripheral devices etc., and by the software operable on the hardware. Concretely speaking, by sequentially carrying out programs on the memory, the data on the memory and the data inputted via the interface are processed, stored, and outputted etc., thereby implementing functions of the respective units. (Hereinafter, the same applies throughout the entire specification).
The ‘storage for inquiry’ ( 0201 ) stores information for forming inquiry relating to an audio-visual environment and option information selected as an answer in response to the inquiry formed on the basis of the information for forming inquiry. The terms ‘(information for forming inquiry) relating to an audio-visual environment’ corresponds to inquiry relating to environment, in which the image display apparatus is used, and mainly corresponds to inquiry relating to usage. Examples of answers (options) include, as shown in FIG. 1 , usage in living room, usage on the desk, usage in the shop or business use, and usage in the bedroom. The ‘information for forming inquiry’ is information for forming the inquiry, and may be an inquiry sentence itself, or may be information indicating an outline or a type etc. of the inquiry. FIG. 3 is a diagram exemplifying information for forming inquiry and option information, which are stored in the storage for inquiry. The information for forming inquiry of FIG. 3 indicates the outline of the inquiry, and its content is ‘Selection of usage’. Additionally, in the storage for inquiry, the information for forming inquiry and the option information are correlated and stored, and in FIG. 3 , option information corresponding to the four answers as shown in FIG. 1 are stored. Thus, the ‘option information’ may be the option itself, or may be information indicating an outline or a type etc. of the option. Additionally, FIG. 3 shows single information for forming inquiry, and there may be a plurality of information for forming inquiry. Moreover, in FIG. 3 , ‘Inquiry ID’ and ‘Option ID’ are identifiers for uniquely identifying the information for forming inquiry and the option information, respectively. The storage for information for forming inquiry stores the information as shown in FIG. 3 in a storage area such as a hard-disk and a semi-conductor memory.
Moreover, the information for forming inquiry may include at least two pieces of information, therefore, information of inquiry for acquiring an image quality control rule for relatively high-level illumination such as the audio-visual environment in the shop, and information of inquiry for acquiring an image control rule for relatively low-level illumination such as the audio-visual environment in the home. FIG. 21 shows an example of the information. In FIG. 21 , the information for forming inquiry corresponds to information relating to an installation place, therefore, two pieces of information of ‘Installation in shop’ and ‘Installation in home’. The option information may be given to each information for forming inquiry in common as in case (a), or may be given with respect to each information for forming inquiry in case (b). Note that in the case of audio-visual environment in the home, the user may be elderly or a user who is not familiar with appliances and it is preferable that the option information is concretely provided as in case (b), so that the option information is more understandable for such user. Moreover, the information relating to the installation place may include a home theater with no illumination etc. other than the shop and the home.
The ‘storage for image quality control rules’ ( 0202 ) stores a plurality of image quality control rules suitable for the audio-visual environment expected according to the option information of the answer. The ‘image quality control rules’ is information indicating details of the control upon image quality control by the after-mentioned image quality controller ( 0205 ). Concretely speaking, for example, the details of the control include controls of luminance, luminance modulation characteristics and image quality (edge enhancement and saturation enhancement). The terms ‘(image quality control rules suitable for) audio-visual environment expected according to the option information’ will be described hereinafter. Here, take the option of FIG. 3 for example, assuming a normal living room in Japan for the option ‘Living room’, it is known from statistics that vertical illumination of a display screen is approximately 200 lx, and viewing distance (distance between the image display apparatus and the user) is approximately. 2.5 m. Therefore, in the audio-visual environment expected according to the option ‘Living room’, ‘the vertical illumination of a display screen is approximately. 200 lx and the viewing distance is approximately. 2.5 m’. Additionally, FIG. 4 is a diagram exemplifying image quality control rules stored in the storage for image quality control rules, and information, which indicates that luminance: 283 cd/m 2 , luminance modulation characteristics: 283 (cd/m 2 ) as criterion, image quality setting: middle, and brightness sensor: OFF, is stored. These correspond to the ‘image quality control rules suitable for audio-visual environment’.
Here, a description of setting method of the image quality control rule is provided. The case of the option ‘Living room (Option ID: A 1 )’ is described. According to a general experimental result, a relation between a display size S (inches) at the vertical illumination 180 lx and at the viewing distance 2.5 m and the most suitable maximum display luminance Y is expressed by Y=−1.0396×S+316.77 (Formula 1). FIG. 13( a ) is a diagram showing the experimental result. In addition, FIG. 13( b ) shows the maximum luminance at the respective display sizes calculated by Formula 1. Here, if the display size is 32 inches, the maximum luminance is approximately 283 cd/m 2 , so that, in FIG. 4 , the luminance of the option ID ‘A 1 ’ is set to 283 cd/m 2 . FIG. 5 is a diagram exemplifying graphs of luminance modulation characteristics. Here, according to statistics, an average signal level of TV broadcasting is approximately. 40%, so that the luminance modulation characteristics are set to ‘283 (cd/m 2 ) as criterion’. This may mean that the luminance modulation characteristics is controlled, so that the luminance at the average signal level 40% is 283 cd/m 2 as shown in FIG. 5( a ), or may mean that the control is carried out, so that the maximum luminance upon the luminance modulation is 283 cd/m 2 as shown in FIG. 5( b ). In FIG. 4 , the image quality is set to middle in the option ID ‘A 1 ’, and specifically, this means that levels of the edge enhancement and the saturation enhancement are set to the middle level. Additionally, the storage for image quality control rules stores the information of FIG. 3 in the storage area such as a hard-disk or a semi-conductor memory.
The ‘first acquirer’ ( 0203 ) outputs the inquiry on the basis of the information for forming inquiry stored in the storage for inquiry, and acquiring result information, which is an option as the answer from a user and is to be utilized for acquiring the image quality control rule. When ‘outputting the inquiry on the basis of the information for forming inquiry’, there are two cases as described above, a case in which the information for forming inquiry is an inquiry sentence itself, and a case that the information for forming inquiry is information indicating an outline or a type etc. of the inquiry. When the information for forming inquiry is an inquiry sentence itself, the information for forming inquiry may be outputted as it is. Meanwhile, when the information for forming inquiry is information indicating an outline or a type etc. of the inquiry, the data of the inquiry sentence corresponding to the information for forming inquiry is stored in the other predetermined storage area, and it is assumed that the information for forming inquiry is outputted to the user. FIG. 6 is a diagram exemplifying inquiries when the inquiries are outputted on the basis of the information for forming inquiry. Note that, as the output method of the inquiry, as shown in FIG. 6 , the inquiry may be displayed on the display screen, or may be audibly outputted by reading the inquiry and option. In addition, the term ‘result information, which is an option as the answer from a user and is to be utilized for acquiring the image quality control rule’ corresponds to the ‘Option ID’ in FIGS. 3 and 4 . Therefore, the terms ‘acquiring result information’ corresponds, for example, to a case that the user selects one option by holding a button of a remote control down while watching a screen of FIG. 6 , the option ID of the option selected according to a signal of the button. Additionally, when outputting the inquiry on the display screen, it is preferable that the entire display screen is dark as shown in FIG. 6 . The reason for this is that when a person watches a bright screen initially, even if an image with sufficient brightness is displayed after that, they feel that it is dark.
Moreover, the ‘first acquirer’ ( 0203 ) may comprise ‘means for displaying an option in a state of provisional selection’. The means for displaying an option in a state of provisional selection is a function of displaying, such that, in a screen for selecting the option to acquire the image quality control rule for the relatively high-luminance or the option to acquire the image quality control rule for the relatively low-luminance, the option for selecting the image quality control rule for the relatively low-luminance is provisionally selected in an initial status. It is preferable that a manufacture of the image display apparatus of the first embodiment sets the option for selecting the image quality control rule to be recommended for the end user to the option in a state of provisional selection. In the state of being provisional selection, the process for the user to ‘select’ one of two options is omitted, and the one option is ‘selected’ and ‘determined’ by a simple process to ‘determine’. For example, an icon for displaying the option for acquiring the image quality control rule for relatively high-level illumination and an icon for displaying the option for acquiring the image quality control rule for relatively low-level illumination are displayed side-by-side, and the user ‘selects’ one of the options through the remote control, and presses the button to ‘determine’ the option, thereby executing the image quality control corresponding to the determined option. Here, when the user ‘selects’ one of the icons, the icon flashes. In this case, the state of icon flashing corresponds to the state of provisional selection. Therefore, the option icon for selecting the image quality control rule for relatively low-level illumination flashes in the initial state. When the user is elderly or is not familiar with appliances, he often operates the apparatus as instructed by the screen display without reading a manual and without thinking. Even in such case, it is possible to select the image quality control rule for relatively low-level illumination suitable for the home use. Moreover, when installing the apparatus in the shop, it is assumed that a person who is familiar with appliances operates it, and he can set the suitable state easily even if the initial state is not suitable for the shop. Therefore, inconveniences are not caused.
FIG. 22 is a functional block diagram of the image display apparatus of the first embodiment. An image display apparatus ( 2200 ) comprises a ‘storage for inquiry’ ( 0201 ), a ‘storage for image quality control rules’ ( 0202 ), a ‘first acquirer’ ( 0203 ), an ‘acquirer for image quality control rule’ ( 0204 ), an ‘image quality controller’ ( 0205 ), a ‘power-on detector’ ( 0206 ), and a ‘setting controller’ ( 0207 ). The ‘first acquirer’ ( 0203 ) may comprise the ‘means for displaying an option in a state of provisional selection’ ( 2201 ). Moreover, an image display apparatus ( 2000 ) may comprise the after-mentioned second acquirer, changer for image quality control rule, changer for image quality control, display for result, and switching interface.
The ‘acquirer for image quality control rule’ ( 0204 ) acquires the image quality control rule from the storage for image quality control rules according to the result information. The ‘result information’ corresponds to the result information acquired by the first acquirer ( 0203 ). Therefore, for example, when information indicating ‘Option ID: A 1 ’ as the result information is acquired by the first acquirer, the image quality control rule in the case that the option ID is ‘A 1 ’ is acquired with reference to the information of FIG. 4 . Concretely speaking, for example, when the information of FIG. 4 is stored as a database in the storage area such as a hard-disk, SQL query to the database for extracting ‘luminance’, ‘luminance modulation characteristics’, and ‘image quality setting’ for the option ID ‘A 1 ’ is executed, thereby acquiring the image quality control rule.
The ‘image quality controller’ ( 0205 ) controls the image quality according to the acquired image quality control rule. The terms ‘acquired image quality control rule’ corresponds to the image quality control rule acquired by the acquirer for image quality control rule ( 0204 ). The term ‘controls the image quality’ means control of the display settings. The term ‘controls the image quality according to the acquired image quality control rule’ means, for example, that when the image quality control rule for the option ID ‘A 1 ’ is acquired by the acquirer for image quality control rule ( 0204 ), the image quality controller controls the luminance to ‘283 cd/m 2 ’, the luminance modulation characteristic to ‘283 (cd/m 2 ) as criterion’, and the image quality setting to ‘middle level’.
Moreover, the image quality control may include any one or more than one of luminance control, luminance modulation characteristics control, color density control, or sharpness control. In this case, it is assumed that the image quality control rule as shown in FIG. 4 includes any one or more than one of luminance control, luminance modulation characteristics control, color density control, or sharpness control.
Additionally, the ‘image quality controller’ ( 0205 ) may include means for controlling image quality of inquiry screen. The ‘means for controlling image quality of inquiry screen’ is a function of controlling image quality of an inquiry screen utilizing the image quality control rule for relatively low-luminance among the image quality control rules stored in the storage for image quality control rules upon outputting the inquiry from the first acquirer. The reason for this is that after a person watches a bright screen, even if an image with sufficient brightness is displayed, they may feel that it is dark, and there is a possibility that the suitable image quality control is not carried out. Note that, the image quality control rule for relatively low-luminance means a rule other than the image quality control rule for highest luminance among the image quality control rules stored in the storage for image quality control rules. For example, when there is the image quality control rule for shop corresponding to the audio-visual environment with a relatively high level of illumination such as the audio-visual environment in the shop and the image quality control rule for home corresponding to the audio-visual environment with a relatively low level of illumination such as the audio-visual environment in the home, the image quality control rule for shop is utilized for the image quality control.
FIG. 23 is a functional block diagram of the image display apparatus of the first embodiment. An image display apparatus ( 2300 ) comprises a ‘storage for inquiry’ ( 0201 ), a ‘storage for image quality control rules’ ( 0202 ), a ‘first acquirer’ ( 0203 ), an ‘acquirer for image quality control rule’ ( 0204 ), an ‘image quality controller’ ( 0205 ), a ‘power-on detector’ ( 0206 ), and a ‘setting controller’ ( 0207 ). The ‘image quality controller’ ( 0205 ) may comprise the ‘means for controlling image quality of inquiry screen’ ( 2301 ). Moreover, an image display apparatus ( 2000 ) may comprise the after-mentioned second acquirer, changer for image quality control rule, changer for image quality control, display for result, and switching interface.
Note that, in the after-mentioned processes on the hardware, the image quality control of a screen for displaying inquiries is carried out by utilizing the image quality control rule for relatively low-luminance.
The ‘power-on detector’ ( 0206 ) detects a power-on. The ‘power-on’ is a power-on upon using the image display apparatus. This power-on may be a power-on of main power, or a power-on after power-off through a remote control etc. in a state that the main power remains on (i.e., standby status). For example, in a concrete processing in the power-on detector, it is determined by a reception of the power-on signal transmitted from the remote control to operate the image display apparatus in the standby status through an infrared reception module that the power is on; therefore, this is the detection of the power-on.
The ‘setting controller’ ( 0207 ) operates the acquirer for image quality control rule according to the detection. The ‘detection’ corresponds to the detection by the ‘power-on detector’ ( 0206 ). The term ‘operates the acquirer for image quality control rule’ means, concretely speaking, that the first acquirer ( 0203 ) is caused to execute the processing, and the ‘acquirer for image quality control rule’ ( 0204 ) is caused to execute the processing. In this case, for example, it is assumed that the setting controller outputs an instruction for execution to the first acquirer, and the first acquirer is ready to execute upon receiving the instruction for execution. The first acquirer executes the processing, in which the execution is triggered by the reception of the instruction for execution, and subsequently, the acquirer for image quality control rule executes processing.
<Processes on Hardware>
FIG. 7 is a diagram exemplifying processes on hardware of the image display apparatus of the first embodiment. At the outset, the information for forming inquiry ( 0701 ) and the option information ( 0702 ) as shown in FIG. 3 are stored in the storage such as the hard-disk or the semi-conductor memory. In addition, a plurality of image quality control rules (a group of image quality control rules) as shown in FIG. 4 are also stored in the storage. These data are developed on the main memory, in which the processing is triggered by the detection of the power-on signal ( 0707 ) by the infrared reception module. Note that, this power-on signal ( 0707 ) corresponds, for example, to the power-on signal from the remote control to operate the image display apparatus. Subsequently, the inquiry is outputted the display etc. on the basis of the information for forming inquiry, and according to this, the result information ( 0704 ) is acquired through the user interface such as the remote control by user's operation. The acquired result information is stored in the main memory. According to the group of image quality control rules and the result information, a suitable image quality control rule ( 0705 ) is selected and stored in the maim memory, thereby executing the image quality control of the display ( 0706 ). Moreover, the storage may store a program for determining the state of provisional selection.
Note that, the processing on the hardware described with reference to FIG. 7 is an example for explaining the outline of the processing. (The same applies throughout the entire specification.)
<Processing Flow of First Embodiment>
FIG. 8 is a flowchart of processes in the image display apparatus of the first embodiment. At the outset, it is determined whether the power is on (S 0801 ). If the power is not on, the step S 0801 is repeated. If it is determined that the power is on, the inquiry on the basis of the information for forming inquiry is outputted (S 0802 ). Subsequently, the result information as the option for the answer to the inquiry is acquired (S 0803 ). Subsequently, the image quality control rule is acquired according to the result information (S 0804 ). Subsequently, the image quality control is executed according to the acquired image quality control rule (S 0805 ).
Note that, it is possible to regard the flowchart of FIG. 8 as a flowchart of a program to be executed by a computer. Moreover, it is possible to store such a program in a medium such as a flexible disk. (The same applies thorough the entire specification.)
<Brief Description of Effects of First Embodiment>
In the image display apparatus of the first embodiment, simple inquires relating to the audio-visual environment are outputted when the power-on is detected, and the only thing the user has to do for suitable image quality control is to answer the simple inquiries, thereby improving user-friendliness.
<<Second Embodiment>>
<Concept of Second Embodiment>
The second embodiment of the present invention is the image display apparatus executes a function of acquiring the image quality control rules only when a power-on is done upon installation of the apparatus.
<Configuration of Second Embodiment>
A configuration of the image display apparatus of the second embodiment is the same as that in FIG. 2 . Moreover, in the apparatus, the above-mentioned power-on detector ( 0206 ) works only when a power-on is done upon installation of the apparatus. The term ‘when a power-on is done upon installation’ means that an initial power-on when the image display apparatus is installed. Therefore, there are cases such as a case that the user does the initial power-on after he purchases the apparatus and places it, or a case that the user does the initial power-on after he moves the apparatus to a new installation place. It is assumed that when the initial power-on after the user purchases the apparatus, the image quality is set to be suitable for the shop, and it is assumed that when the installation place is changed, normally, the audio-visual environment also changes. Additionally, examples of a method for determining the initial power-on after the installation of the apparatus include a case that a flag is set on a flash memory in the image display apparatus upon shipment from a factory, and the flag indicates no power-on by the user, so that the initial power-on after the installation is determined, a case that the initial power-on after the installation is determined by passage of a long period since the last power-off, and a case that the initial power-on after the installation is determined by equipping a switch which is released upon moving the image display apparatus with the apparatus, thereby detecting the change of the installation place. As the concrete processing of the power-on detector, for example, when the power-on of the image display apparatus is done, it is detected that the flag indicates no power-on, thereby determining the initial power-on. After that, the flag is set so as to indicate the power-on. Moreover, as another method, when the power-on of the image display apparatus is done, the date and time of the last power-off and the current date and time are compared, and if a predetermined period of time passes, the initial power-on after the installation is determined Thus, the initial power-on after the installation is determined.
<Processes on Hardware>
The processes on hardware of the image display apparatus of the second embodiment are the same as those of FIG. 7 . Moreover, the processes of FIG. 7 are executed only when a power-on is done upon installation of the apparatus
<Processing Flow of Second Embodiment>
FIGS. 10( a ) and 10 ( b ) are flowcharts of processes in the image display apparatus of a second embodiment. At the outset, the flowchart of FIG. 10( a ) is explained. It is determined whether the power-on has been done in the past (S 1001 ). This is determined by the flag in the flash memory. If the power-on has been done (NO), the processing is terminated. If the power-on has not been done (YES), the power-on detector determines the power-on (S 0801 ). If the power-on is not detected, the step S 0801 is repeated. If it is determined the power is on, the inquiry on the basis of the information for forming inquiry is outputted (S 0802 ). Subsequently, the result information as the option for the answer to the inquiry is acquired (S 0803 ). Subsequently, the image quality control rule is acquired according to the result information (S 0804 ). Subsequently, the image quality control is executed according to the acquired image quality control rule (S 0805 ).
Subsequently, the flowchart of FIG. 10( b ) is explained. At the outset, it is determined whether the power is on (S 0801 ). If the power-on is not detected, the step S 0801 is repeated. If it is determined the power is on, it is determined whether it is the initial power-on (S 1001 ). If it is not the initial power-on after the installation, the processing returns to step S 0801 . If it is the initial power-on after the installation, the inquiry on the basis of the information for forming inquiry is outputted (S 0802 ). Subsequently, the result information as the option for the answer to the inquiry is acquired (S 0803 ). Subsequently, the image quality control rule is acquired according to the result information (S 0804 ). Subsequently, the image quality control is executed according to the acquired image quality control rule (S 0805 ).
Note that, in flowcharts of this specification, the same reference number is given to the same processing.
<Brief Description of Effects of Second Embodiment>
In the image display apparatus of the second embodiment, when the installation place is changed and the audio-visual environment changes, the image quality control suitable for the audio-visual environment after change is automatically carried out.
<<Third Embodiment>>
<Concept of Third Embodiment>
The third embodiment of the present invention is the image display apparatus acquiring display size information as the result information.
<Configuration of Third Embodiment>
FIG. 11 is a functional block diagram of the image display apparatus of the third embodiment. An image display apparatus ( 1100 ) comprises a ‘storage for inquiry’ ( 0201 ), a ‘storage for image quality control rules’ ( 0202 ), a ‘first acquirer’ ( 0203 ), an ‘acquirer for image quality control rule’ ( 0204 ), an ‘image quality controller’ ( 0205 ), a ‘power-on detector’ ( 0206 ), a ‘setting controller’ ( 0207 ), and a ‘second acquirer’ ( 1101 ). The configurations other than the ‘second acquirer’ ( 1101 ) are the same as those above-described, so that descriptions are omitted. Note that, in functional block diagrams of this specification, the same reference number is given to the same component.
The ‘second acquirer’ ( 1101 ) acquires display size information as the result information. The acquired display size information as the result information is used for acquiring the image quality control rule by the ‘acquirer for image quality control rule’ ( 0204 ). Normally, the image display apparatus recognizes its display size (stores it internally as the information), so that the term ‘acquisition’ of the display size information in the second acquirer corresponds to reading out the display size information from the internal storage. If such information is not stored internally, the information may be acquired from external apparatus or by user's input operation. Moreover, the above-mentioned first acquirer ( 0203 ) also acquires the option as the result information, and the first acquirer ( 0203 ) and the second acquirer ( 1101 ) may be configured by the same circuit or by different circuit.
FIG. 12 is a diagram exemplifying image quality control rules, which are stored in the storage for image quality control rules, and are used for image quality control on the basis of display size. For example, in the case of the option ID ‘A 1 ’ (Living room), as described above, according to the experimental result of FIG. 13( a ), it is known that the most suitable maximum luminance is determined by Y=−1.0396×S+316.77 (Formula 1). FIG. 13( b ) shows the maximum luminance at the respective display sizes calculated by the formula 1. Therefore, these values are indicated as the luminance values at the respective display sizes in the option ID ‘A 1 ’ in FIG. 12 (numbers after the decimal point are truncated). As for the luminance modulation characteristics, FIG. 14 is a diagram exemplifying graphs of luminance modulation characteristics in each display size. FIG. 14 shows a graph of luminance modulation characteristics in a 16-inch display ( 1401 a and 1401 b ), a graph of luminance modulation characteristics in a 32-inch display ( 1402 a and 1402 b ), and a graph of luminance modulation characteristics in a 65-inch display ( 1403 a and 1403 b ) as representative examples. Similar to FIG. 5 , it is known that the average signal level of TV broadcasting is approximately. 40%. Therefore, the luminance modulation characteristics may be controlled, so that, as in FIG. 14( a ), the luminance at the average signal level 40% is the maximum luminance at the respective display sizes, or may be controlled, so that, as in FIG. 14( b ), the maximum luminance upon luminance modulation is the same value as the suitable maximum luminance. Additionally, FIG. 15 explains the ‘image quality setting’ of FIG. 12 . Generally, it is known that, for human eyes, as image size is reduced, the image gets blurry and its saturation lowers. Accordingly, as the display size is reduced, the edge enhancement and the saturation enhancement are set to higher. Therefore, in the ‘image quality setting’ of FIG. 12 , as the display size is reduced, the image quality setting is set to a higher level, and as the display size is increased, the image quality setting is set to lower level. Additionally, the audio-visual environment expected for the option ID ‘A 2 ’ (on the desk) is ‘the vertical illumination 180 lx and at the viewing distance 3H (3 times of height of the display)’, and in this case, it is known from general experimental result that the suitable maximum luminance is ‘240 cd/m 2 ’ which is common for all sizes. In addition, as the image quality setting, since the viewing distance is short, the setting value is set to lower for all display sizes ( FIG. 12) . Additionally, the audio-visual environment expected for the option ID ‘A 3 ’ (in the shop and business user) is an environment with brighter light such as in an office, so that the luminance is set to maximum value and the luminance modulation characteristics is fixed. Moreover, as to the image quality setting, since the ambient brightness is high, the edge enhancement and the saturation enhancement are set to totally higher ( FIG. 12 ). In addition, in the option ID ‘A 4 ’ (bedroom), the luminance, the luminance modulation, and the image quality setting are set to the same as those in the option ‘A 1 ’. Note that the brightness sensor is set to ‘ON’, the brightness in the bedroom is measured by the brightness sensor, thereby adjusting the image quality setting.
<Processes on Hardware>
The processes on hardware of the image display apparatus of the third embodiment are the same as those of FIG. 7 . Moreover, the information of FIG. 12 is stored in the storage as the ‘group of image quality control rules’, and the display size is acquired as the result information.
<Processing Flow of Third Embodiment>
FIG. 16 is a flowchart of processes in the image display apparatus of the third embodiment.
At the outset, it is determined whether the power is on (S 0801 ). If the power is not on, step S 0801 is repeated. If it is determined the power is on, the inquiry on the basis of the information for forming inquiry is outputted (S 0802 ). Subsequently, the result information as the option for the answer to the inquiry is acquired (S 0803 ). Subsequently, the display size is acquired as the result information (S 1601 ). Subsequently, the image quality control rule is acquired according to the result information (S 0804 ). Subsequently, the image quality control is executed according to the acquired image quality control rule (S 0805 ).
<Brief Description of Effects of Third Embodiment>
In the image display apparatus of the third embodiment, the image quality control is carried out on the basis of the display size of the image display apparatus, thereby carrying out the proper image quality control.
<<Fourth Embodiment>>
<Concept of Fourth Embodiment>
The fourth embodiment of the present invention is the image display apparatus, in which the image quality control rule can be changed.
<Configuration of Fourth Embodiment>
FIG. 17 is a functional block diagram of the image display apparatus of the fourth embodiment. An image display apparatus ( 1700 ) comprises a ‘storage for inquiry’ ( 0201 ), a ‘storage for image quality control rules’ ( 0202 ), a ‘first acquirer’ ( 0203 ), an ‘acquirer for image quality control rule’ ( 0204 ), an ‘image quality controller’ ( 0205 ), a ‘power-on detector’ ( 0206 ), a ‘setting controller’ ( 0207 ), and a ‘changer for image quality control rule’ ( 1701 ). Moreover, the image display apparatus ( 1700 ) may further comprise the second acquirer. The configurations other than the ‘changer for image quality control rule’ ( 1701 ) are the same as those above-described, so that descriptions are omitted.
The ‘changer for image quality control rule’ ( 1701 ) changes the image quality control rules used by the image quality controller. Therefore, the image quality control rules as shown in FIGS. 4 and 12 can be changed. For example, the screen for setting the image quality control rule is displayed on the display screen, and the user inputs the changes through the screen for setting the image quality control rule by using a keyboard or a mouse etc., thereby changing the image quality control rules stored in the storage according to the input signals. Concretely speaking, for example, when the information of FIG. 4 or 12 is stored in the storage such as a hard-disk as the database, the SQL query to be executed for the database is generated and executed according to the input signals by the user's operation through the screen for setting the image quality control rule, thereby changing the image quality control rule. Moreover, the changer for image quality control rule may include a program for executing such processing.
<Processes on Hardware>
The processes on hardware of the image display apparatus of the fourth embodiment are the same as those of FIG. 7 . Moreover, the program etc. for changing the ‘group of image quality control rules’ stored in the storage is executed.
<Processing Flow of Fourth Embodiment>
The processes in the image display apparatus of the fourth embodiment are the same as those of the above-mentioned embodiment, and moreover, the processing of changing the ‘image quality control rules’ is further executed.
<Brief Description of Effects of Fourth Embodiment>
In the image display apparatus of the fourth embodiment, the image quality control rules can be changed, so that when a predetermined image quality control rule needs to be changed depending on the actual audio-visual environment or on the user's taste, the image quality control rules are changed.
<<Fifth Embodiment>>
<Concept of Fifth Embodiment>
The fifth embodiment of the present invention is the image display apparatus, in which the image quality control can be changed.
<Configuration of Fifth Embodiment>
FIG. 18 is a functional block diagram of the image display apparatus of the fourth embodiment. An image display apparatus ( 1800 ) comprises a ‘storage for inquiry’ ( 0201 ), a ‘storage for image quality control rules’ ( 0202 ), a ‘first acquirer’ ( 0203 ), an ‘acquirer for image quality control rule’ ( 0204 ), an ‘image quality controller’ ( 0205 ), a ‘power-on detector’ ( 0206 ), a ‘setting controller’ ( 0207 ), and a ‘changer for image quality control’ ( 1801 ). Additionally, the image display apparatus ( 1800 ) may further comprise the second acquirer. Additionally, the image display apparatus ( 1800 ) may further comprise ‘changer for image quality control rule’. The configurations other than the ‘changer for image quality control’ ( 1801 ) are the same as those above-described, so that descriptions are omitted.
The ‘changer for image quality control’ ( 1801 ) changes the image quality control in priority to the image quality control by the image quality controller. The term ‘in priority to the image quality control by the image quality controller’ means that image quality control can further be carried out after the image quality control by the image quality controller. In the ‘image quality controller’ ( 0205 ), as described above, the image quality control is basically carried out in accordance with the image quality control rule. Moreover, by the changer for image quality control, it is possible to do fine adjustment of the image quality control, for example, according to the user's operation or to the detection result of the brightness sensor. Note that, a difference between the changer for image quality control and the changer for image quality control rule is that the changer for image quality control does not execute the change of the image quality control rule itself. For example, the screen for adjusting the image quality is displayed on the display screen, and the user inputs the changes through the screen for adjusting the image quality by using a keyboard or a mouse etc., thereby carrying out the image quality control according to the input signals. Alternatively, the image display apparatus is provided with the buttons etc. for adjusting the image quality to adjust the luminance, edge enhancement, and saturation enhancement, and the user operates the buttons for adjusting the image quality, thereby carrying out the image quality control.
Moreover, the changer for image quality control may include a program for executing such processing.
<Processes on Hardware>
The processes on hardware of the image display apparatus of the fifth embodiment are the same as those of FIG. 7 . Moreover, the processing for image quality control is further executed in addition to the basic processing as described in FIG. 7 .
<Processing Flow of Fifth Embodiment>
FIG. 19 is a flowchart of processes in the image display apparatus of the fifth embodiment. At the outset, it is determined whether the power is on (S 0801 ). If the power is not on, step S 0801 is repeated. If it is determined the power is on, the inquiry on the basis of the information for forming inquiry is outputted (S 0802 ). Subsequently, the result information as the option for the answer to the inquiry is acquired (S 0803 ). Subsequently, the image quality control rule is acquired according to the result information (S 0804 ). Subsequently, the image quality control is executed according to the acquired image quality control rule (S 0805 ). Subsequently, the image quality control is changed (S 1901 ).
<Brief Description of Effects of Fifth Embodiment>
In the image display apparatus of the fifth embodiment, the image quality control can be adjusted in addition to the basic processing of the image quality control according to the image quality control rule, so that when a predetermined image quality control rules are necessarily to be adjusted depending on the actual audio-visual environment or on the user's taste, the image quality control are adjusted.
<<Sixth Embodiment>>
<Concept of Sixth Embodiment>
The sixth embodiment of the present invention is the image display apparatus displaying the result of acquiring the image quality control rule.
<Configuration of Sixth Embodiment>
FIG. 20 is a functional block diagram of the image display apparatus of the sixth embodiment. An image display apparatus ( 2000 ) comprises a ‘storage for inquiry’ ( 0201 ), a ‘storage for image quality control rules’ ( 0202 ), a ‘first acquirer’ ( 0203 ), an ‘acquirer for image quality control rule’ ( 0204 ), an ‘image quality controller’ ( 0205 ), a ‘power-on detector’ ( 0206 ), a ‘setting controller’ ( 0207 ), and a ‘display for result’ ( 2001 ). Additionally, the image display apparatus ( 2000 ) may further comprise the second acquirer. Additionally, the image display apparatus ( 2000 ) may further comprise ‘changer for image quality control rule’. Additionally, the image display apparatus ( 2000 ) may further comprise ‘changer for image quality control’. The configurations other than the ‘display for result’ ( 2001 ) are the same as those above-described, so that descriptions are omitted.
The ‘display for result’ ( 2001 ) has a function of displaying the result acquired by the acquirer for image quality control rule. The term ‘displaying the result acquired by the acquirer for image quality control rule’ means that the details of the image quality control rule are mainly displayed. For example, when acquiring the image quality control rule for the option ID ‘A 1 ’ in FIG. 4 , the indication as ‘image quality control is carried out at luminance: 283 cd/m 2 , luminance modulation characteristics: 283 (cd/m 2 ) as criterion, image quality setting: middle level’ is displayed on the display screen. Moreover, the display for result displays the result, and the user checks the details of the control, so that the image quality control may be executed only when the user holds the OK button down.
<Processes on Hardware>
The processes on hardware of the image display apparatus of the sixth embodiment are the same as those of FIG. 7 . Moreover, the processing for generating the drawing data for displaying the acquired image quality control rule in Video RAM and of outputting it to the display is carried out in addition to the basic processing as described in FIG. 7 .
<Processing Flow of Sixth Embodiment>
FIG. 9 is a flowchart of processes in the image display apparatus of the sixth embodiment.
At the outset, it is determined whether the power is on (S 0801 ). If the power is not on, step S 0801 is repeated. If it is determined the power is on, the inquiry on the basis of the information for forming inquiry is outputted (S 0802 ). Subsequently, the result information as the option for the answer to the inquiry is acquired (S 0803 ). Subsequently, the image quality control rule is acquired according to the result information (S 0804 ). Subsequently, the image quality control is executed according to the acquired image quality control rule (S 0805 ). Subsequently, the result of acquiring the image quality control rule is displayed (S 0901 ). Note that, step S 0901 may he executed in priority to step S 0805 .
<Brief Description of Effects of Sixth Embodiment>
In the image display apparatus of the sixth embodiment, the acquired image quality control rule is displayed, so that the user can clearly figure out the executed image quality control.
<<Seventh Embodiment>>
<Concept of Seventh Embodiment>
The seventh embodiment of the present invention is the image display apparatus having two selectable image quality modes to select high or low level of luminance in one audio-visual environment mode.
<Configuration of Seventh Embodiment>
FIG. 24 is a functional block diagram of the image display apparatus of the seventh embodiment. An image display apparatus ( 2400 ) comprises a ‘storage for inquiry’ ( 0201 ), a ‘storage for image quality control rules’ ( 0202 ), a ‘first acquirer’ ( 0203 ), an ‘acquirer for image quality control rule’ ( 0204 ), an ‘image quality controller’ ( 0205 ), a ‘power-on detector’ ( 0206 ), a ‘setting controller’ ( 0207 ), and a ‘switching interface’ ( 2401 ). The ‘acquirer for image quality control rule’ ( 0204 ) comprises ‘means for displaying an icon’ ( 2402 ). Additionally, the image display apparatus ( 2400 ) may further comprise the second acquirer. Additionally, the image display apparatus ( 2000 ) may further comprise ‘changer for image quality control rule’. Additionally, the image display apparatus ( 2000 ) may further comprise ‘changer for image quality control’. Additionally, the image display apparatus ( 2000 ) may further comprise the ‘display for result’. The configurations other than the ‘switching interface’ ( 2401 ) and the ‘means for displaying an icon’ ( 2402 ) are the same as those above-described, so that descriptions are omitted.
The ‘switching interface’ ( 2401 ) has a function of switching between a first image quality mode and a second image quality mode. Here, the first image quality mode is for displaying an image with relatively high-luminance, and the second image quality mode is for displaying an image with relatively low-luminance. The first and second image quality modes are selectable for a first audio-visual environment with relatively high level of illumination and for a second audio-visual environment with relatively low level of illumination, respectively. Note that, in the first audio-visual environment mode, the image quality control rule for the audio-visual environment with relatively high level of illumination such as the audio-visual environment in the shop is selectable, and in the second audio-visual environment mode, the image quality control rule for the audio-visual environment with relatively low level of illumination such as the audio-visual environment in the home is selectable. Accordingly, after selecting one audio-visual environment on the basis of difference in brightness level, it is possible to select high or low level of luminance, thereby carrying out advanced image quality control in a simple manner.
Note that, it is preferable that the luminance in the first image quality mode and that in the second image quality mode in each of the first audio-visual environment mode and the second audio-visual environment mode are set to be different. The reason for this is that the suitable luminance differs depending on the audio-visual environment, and the luminance variable width also differs. For example, in the case of installing the apparatus in the shop, illumination in the sales floor for image display apparatus is high and large-sized apparatus is placed therein In addition, it is necessary to show the difference between the first and second image quality modes to a customer in an easy-understandable manner, and to persuade the customer that a high-precision image quality control is possible. Meanwhile, in the case of installing the apparatus in the home, in comparison with the case of the shop, illumination is low and small-sized display is placed therein In addition, it is necessary to control the image quality, thereby providing comfortable longtime-viewing without visual fatigue. Thus, although the image quality control in the shop and that in the home are actually different, it is necessary to make the user recognize them to be the same. For example, in FIG. 25 , in the first audio-visual environment, the luminance in the first image quality mode and that in the second image quality mode are ‘450 cd/m 2 ’ and ‘350 cd/m 2 ’, respectively. In the second audio-visual environment, the luminance in the first image quality mode and that in the second image quality mode are ‘300 cd/m 2 ’ and ‘240 cd/m 2 ’, respectively. Therefore, by using the same icon, the user recognizes that the same function of image quality control works even if luminance and luminance difference are not the same as those in the shop.
The ‘means for displaying an icon’ ( 2402 ) has a function of displaying an icon, such that an icon for the first image quality mode in the first audio-visual environment mode and that in the second audio-visual environment mode are same, and such that an icon for the second image quality mode in the first audio-visual environment mode and that in the second audio-visual environment mode are same. The purpose of this function is that, in the home, the user can experience the luminance difference in the shop between the first image quality mode and the second image quality mode. As described above, it is preferable that the image quality settings for first image quality mode and the second image quality mode in the first audio-visual environment mode are set to be different from the image quality settings for first image quality mode and the second image quality mode in the second audio-visual environment mode. The reasons for this are that the brightness in the shop is higher than that in the home, it is necessary to show the luminance difference clearly, and the display size in the shop is large. However, in the home, the user wishes to do the same image quality control as that in the shop. This is consumer mind Therefore, in the image display apparatus of the seventh embodiment, the luminance of the first image quality mode and the second image quality mode in the second audio-visual environment mode are set to be suitable for the audio-visual environment with relatively low illumination, and icons are shared in the first and second audio-visual environments, so that when switching the image quality modes in the first audio-visual environment mode, the user can experience the switching of the image quality modes in the second audio-visual environment mode. Therefore, the same icon is used, so that the user need not be conscious of the difference between the first and second audio-visual environment modes, and the corrections for suitable luminance in the respective audio-visual environment modes are carried out. Note that, the term ‘same’ means similar and recognizable at a glance, and includes what is termed ‘a scope of similarity’ in trademark and design patent.
<Processes on Hardware>
The processes on hardware of the image display apparatus of the seventh embodiment are the same as those of FIG. 7 . Moreover, the processing for switching between two different image quality modes with different luminance settings is carried out in addition to the basic processing as described in FIG. 7 .
<Processing Flow of Seventh Embodiment>
FIG. 26 is a flowchart of processes in the image display apparatus of the seventh embodiment.
At the outset, it is determined whether the power is on (S 0801 ). If the power is not on, step S 0801 is repeated. If it is determined the power is on, the inquiry on the basis of the information for forming inquiry is outputted (S 0802 ). Here, selection of the audio-visual environment mode is executed (S 2601 ), and selection of the image quality mode is executed (S 2602 ). Subsequently, the result information as the option for the answer to the inquiry is acquired (S 0803 ). Subsequently, the image quality control rule is acquired according to the result information (S 0804 ). Subsequently, the image quality control is executed according to the acquired image quality control rule (S 0805 ).
<Brief Description of Effects of Seventh Embodiment>
In the image display apparatus of the seventh embodiment, the icons for the same image quality modes in the different audio-visual environment modes are same, so that in the home, the user can experience the same image quality control as that in the shop, and he can easily do image quality control suitable for viewing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a conceptual diagram showing operations of an image display apparatus of the present invention.
FIG. 2 is a functional block diagram of the image display apparatus of a first embodiment.
FIG. 3 is a diagram exemplifying information for forming inquiry and option information, which are stored in the storage for inquiry.
FIG. 4 is a diagram exemplifying image quality control rules stored in a storage for image quality control rules.
FIG. 5 is a diagram exemplifying graphs of luminance modulation characteristics
FIG. 6 is a diagram exemplifying inquiries.
FIG. 7 is a diagram exemplifying processes on hardware of the image display apparatus.
FIG. 8 is a flowchart of processes in the image display apparatus of the first embodiment.
FIG. 9 is a flowchart of processes in the image display apparatus of a sixth embodiment.
FIG. 10 is a flowchart of processes in the image display apparatus of a second embodiment.
FIG. 11 is a functional block diagram of the image display apparatus of a third embodiment.
FIG. 12 is a diagram exemplifying image quality control rules on the basis of display size.
FIG. 13 is a diagram exemplifying experimental result relating the display size and luminance.
FIG. 14 is a diagram exemplifying graphs of luminance modulation characteristics in each display size.
FIG. 15 is a diagram showing a relation between the display size and setting of image quality.
FIG. 16 is a flowchart of processes in the image display apparatus of a third embodiment.
FIG. 17 is a functional block diagram of the image display apparatus of a fourth embodiment.
FIG. 18 is a functional block diagram of the image display apparatus of a fifth embodiment.
FIG. 19 is a flowchart of processes in the image display apparatus of the fifth embodiment.
FIG. 20 is a functional block diagram of the image display apparatus of a sixth embodiment.
FIG. 21 is a diagram exemplifying information for forming inquiry and option information, which are stored in the storage for inquiry.
FIG. 22 is a functional block diagram of the image display apparatus of the first embodiment.
FIG. 23 is a functional block diagram of the image display apparatus of the first embodiment.
FIG. 24 is a functional block diagram of the image display apparatus of a seventh embodiment.
FIG. 25 is a diagram exemplifying icons for an image quality mode of the seventh embodiment.
FIG. 26 is a flowchart of processes in the image display apparatus of the seventh embodiment.
DESCRIPTION OF REFERENCE NUMERALS
0101 Power-on
0102 Output of inquiries relating to audio-visual environment
0103 Inquiries relating to audio-visual environment
0104 Option
0105 Option
0106 Option
0107 Option
0201 Storage for inquiry
0202 Storage for image quality control rules
0203 First acquirer
0204 Acquirer for image quality control rule
0205 Image quality controller
0206 Power-on detector
0207 Setting controller
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In general, when a user views an image displayed on a display apparatus, visual environments, such as ambient brightness, a distance from the user to the display apparatus and so on, may disadvantageously cause the image displayed on the display apparatus to become difficult to view. Moreover, it is complicated and troublesome for the user to enter information of ambient light amount and others when setting a picture quality. An image display apparatus holds both question constituent information related to visual environments and choice information serving as answers to questions constituted by the question constituent information, and further holds a plurality of picture quality control rules suitable for visual environments assumed in accordance with the choice information serving as the answers. When sensing a power-up, the image display apparatus outputs the questions; acquires result information that is choices serving as answers from the user to those questions and that is used to acquire the picture quality control rules; and controls the picture quality in accordance with the picture quality control rules acquired in accordance with the result information.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention pertains to a fluid actuator and more particularly to a hydraulic actuator having a piston and a valve means wherein a force applied to the valve means is varied resulting in a frequency change of piston reciprocation.
2. Description of the Prior Art
In U.S. Pat. No. 4,143,447 to Krasnoff et al. and U.S. Pat. No. 4,192,219 to Krasnoff et al., a hydraulically operated reciprocating piston is described wherein the piston in cooperation with a cushion chamber, a liquid supply source and a valve means reciprocate the piston.
These apparatuses are useful in hydraulic rock drilling operations. Drilling hard rock calls for high energy blow at any given power level. This is especially important when drilling deep holes. Soft rock requires a lower blow energy and force level for optimum penetration at a given power level. In the above mentioned patents, in order to change the blow energy and frequency of reciprocation of the piston it is necessary to change the design of the apparatus. A single rock drill actuator of small size and high efficiency for both hard and soft rock is desirable.
SUMMARY OF THE INVENTION
This invention relates to a fluid actuator having a housing and a fluid supply source for supplying pressurized fluid to the fluid actuator. A piston chamber is also provided within the housing. A piston mounted within the piston chamber is provided. First means for moving the piston in a first direction, second means for moving the piston in a second direction, and means for producing an increasing and decreasing fluid pressure source is also provided. A valve means communicates with the liquid supply source and the increasing and decreasing pressure source producing a first and second force on the valve means. The valve means actuates the first and second piston means when the valve is in a first and second position respectively. A means for varying at least one of the valve forces is provided which controls the frequency of reciprocation of the piston.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of a fluid actuator showing one position of the piston and the valve.
FIG. 2 is a schematic illustration of a fluid actuator showing the piston and valve in another position.
FIG. 3 is a graph plotting piston displacement versus time.
FIG. 4 is a schematic illustration showing a means for modifying the force applied to the valve.
FIG. 5 is a schematic illustration showing a means for modifying the force applied to the valve.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1 a fluid actuator is shown. Fluid actuator 10 comprises a housing 12. Housing 12 may be a single casting, segments bolted or welded together by conventional means or several segments interconnected with conventional means such as tubing. Within housing 12 is a cushion chamber 14. Fluid source 16 supplies pressurized fluid to fluid actuator 10 which provides the energy source for reciprocating fluid piston 28. Fluid source includes conventional sources such as hydraulic and pneumatic supply sources. Cushion chamber 14 is filled with fluid by means of valve 19. Valve 19 includes conventional valves such as pressure check valves. Within housing 12 is a piston chamber 18 which comprises a first piston chamber 20 and a second piston chamber 22. A bore 24 formed in the housing 12 separates the first piston chamber 20 from the second piston chamber 22. A bore 26 also formed in the housing 12 interconnects the cushion chamber 14 with first piston chamber 20. Within piston chamber 18 is located a piston 28. Piston 28 extends into cushion chamber 13. Piston 28 comprises a first pressure surface 30 located within first piston chamber 20 and a second pressure surface 32 located within second piston chamber 22. Piston 28 also comprises cushion chamber pressure surface 34 located within cushion chamber 14.
A valve 36 is provided for reciprocating piston 28. Valve 36 may be comprised of one piece or be comprised of a body 37 with one or more pins in contact with body 37 such as pins 39 and 41, shown in FIGS. 1 and 2. Valve 36 has a first valve surface 38 for communicating with cushion chamber 14 by means of passage 40. Valve 36 also has a second valve surface 42 for communicating with pressure source 16 through passage 44. Valve 36 has a first port 46 which communicates with fluid source 16 through passage 48 and a second port 50 which communicates with first piston chamber 20 by means of passage 52. Valve 36 also contains a third port 54 which communicates with a fluid exhaust means 56 by means of passage 58. Ports 60 and 62 also communicate with fluid exhaust means 56. As shown in FIG. 1 piston 28 is shown in a first position and valve 36 is shown in a first position. Fluid from fluid source 16 enters second piston chamber 22 and exerts pressure on surface 32. Valve 36 shown in the first position in FIG. 1 permits port 50 to communicate with port 54 wherein liquid from first piston chamber 20 communicates with exhaust means 56. This forces piston 28 to move in a first direction towards a second piston position as shown in FIG. 2. As piston 28 moves in a first direction surface 34 compresses the fluid in cushion chamber 14. The pressure in cushion chamber 14 times surface area 38 produces a first force on valve 36 tending to move valve 36 from the first position to a second position as shown in FIG. 2. This movement is opposed by a second force resulting from the pressure of liquid source 16 times surface area 42. As piston 28 moves to the second position the pressure in cushion chamber 14 increases and the first force on valve 36 exceeds the second force wherein valve 38 moves to the second position. When valve 36 is in the second position port 46 communicates with port 50. Thus first piston chamber 20 communicates with liquid source 16 rather than communicating with exhaust means 56. The pressure in first pressure chamber 20 is thus increased. The increased pressure in first piston chamber 20 acting on surface 30 in conjunction with the cushion chamber pressure acting on surface 34 overcomes the force produced by the pressure in second pressure chamber 22 acting on surface 32. Piston 28 then moves in a second direction to the first position as shown in FIG. 1. Piston 28 has a striking surface 62 which strikes a surface 64 which surface includes drill steel surfaces. As piston 28 moves to the first position, the pressure in chamber 14 decreases. As the pressure in chamber 14 decreases, supply pressure 16 times area 42 is greater than cushion chamber pressure 14 times 38. Valve 36 then moves to position 1 as shown in FIG. 1. The pressure in first piston chamber 20 decreases since chamber 20 communicates with exhaust means 56 rather than source 16. The cycle is completed and begins to repeat itself.
According to the present invention at least one of the valve forces is pressurized by a selected portion of the supplied fluid pressure. This changes the operating characteristics of the cycle and hence the frequency of reciprocation.
FIG. 3 is a plot of piston displacement verses time. Point S of curve A is the position of piston 28 at the first position as shown in FIG. 1. Point T is the position of 28 at the second position as shown in FIG. 2. Point R is the position of Piston 28 returned to the first position as shown in FIG. 1, thus completing the cycle. In one embodiment of this invention the second force on surface 42 is reduced, the cycle time and piston displacement is decreased as shown by curve B. If the second force is varied with an increased force, the cycle time and piston displacement will be increased as shown by curve C. Force control means for varying the second force applied to valve 36 include conventional means as shown in FIGS. 4 and 5.
In FIG. 4, valves 80 and 82 control the pressure on 42. As valve 82 is opened and valve 80 is closed, the pressure on surface 42 decreases and the period of piston 28 decreases. As valve 82 is closed and valve 80 is opened, the pressure on surface 42 increases causing the period of piston 28 to increase.
In FIG. 5 a pin 84 is shown which has a surface 86 and a surface 88. A valve 90 is also provided. When valve 90 is open, the second force on piston 36 is supply pressure 16 times area 86 plus area 88. When valve 90 is closed, the second force on valve 36 is supply pressure 16 times area 88 only and accordingly the period of piston 28 is decreased. This embodiment provides for an incremental change in piston frequency where as the embodiment shown in FIG. 5 provides for a continuous change in frequencies. Similar devices may be employed to bias the first force applied to valve 36.
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This invention pertains to a fluid actuator having piston chambers, a piston maintained within said chambers, a valve means for reciprocating the piston and a pressure control means for varying the force to the valve means wherein the reciprocating frequency of the piston is modulated.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit of U.S. Provisional Application No. 62/127,315, filed Mar. 3, 2015, entitled SYSTEM AND METHOD FOR MANAGING DRUG DISPENSING TO PATIENTS (Atty. Dkt. No. RDPH-32513), the specification of which is incorporated by reference herein in its entirety.
TECHNICAL FIELD
[0002] The present invention relates to a patient data management system, and more particularly, to a system for tracking patient and medication data from a plurality of treatment locations at a centralized point.
BACKGROUND
[0003] Within healthcare facilities there is often in need for dispensing drugs to patients. These drugs may be for physical or psychological issues and many of these drugs comprise controlled substances under government regulations and guidelines. Patients often require a wide variety of drugs and treatment therapies. In order to make sure that drug treatment and therapies do not adversely interact with each other, there is a need for some type of management between healthcare providers and medication dispensing in order to ensure best patient care practices. Tracking patients and their clinical data as the patients move between healthcare facilities creates a need for tracking and centrally locating information to improve patient care.
SUMMARY
[0004] The present invention, as disclosed and described herein, comprises a system for managing patient data for patients moving between a plurality of different patient care facilities includes a first interface for connecting to the plurality of patient care facilities to receive past patient care data. A second interface provides outputs to a current health care provider. A database stores the received past patient care data. A processor includes a set of instructions to configure the processor to monitor the past patient care data with respect to a particular patient and generate an alert to the health care provider over the second interface responsive to a determination that the past patient care data from the plurality of patient care facilities indicates a patient care problem.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] For a more complete understanding, reference is now made to the following description taken in conjunction with the accompanying Drawings in which:
[0006] FIG. 1 illustrates a system for managing patient care and medication information from a central location;
[0007] FIG. 2 illustrates a block diagram of an ACT system;
[0008] FIG. 3 illustrates the operation of the decision support tools of the ACT system;
[0009] FIG. 4 illustrates alert generation by the ACT system; and
[0010] FIG. 5 illustrates 340 -B functionalities within the ACT system.
DETAILED DESCRIPTION
[0011] Referring now to the drawings, wherein like reference numbers are used herein to designate like elements throughout, the various views and embodiments of a system and method for managing drug dispensing to patients are illustrated and described, and other possible embodiments are described. The figures are not necessarily drawn to scale, and in some instances, the drawings have been exaggerated and/or simplified in places for illustrative purposes only. One of ordinary skill in the art will appreciate the many possible applications and variations based on the following examples of possible embodiments.
[0012] Referring now to the drawings, and more particularly to FIG. 1 , there is illustrated the use of an ACT (Accountable Cloud Technology) system for managing patient care and medication information at a central location. Within healthcare facilities patient care often requires providing various types of medications and treatments to the patients in order to improve their condition. These drugs may be used to treat physical or psychological issues and in some cases comprise controlled substances that must be supplied under government regulations and guidelines. When patients are moving from treatment facility to treatment facility due to their current state of treatment, the opportunity arises for the drug and treatment therapies to adversely interact with each other. The ACT system 102 provides for management of data between healthcare providers and medication dispensing in order to ensure best patient care practices and ensure that drug and treatment therapies do not adversely interact with each other. The ACT system 102 tracks patients and their clinical data as they move between care facilities and creates a meaningful opportunity to facilitate the transformation of clinical care and improve patient care.
[0013] The ACT system 102 is a centralized data management bridge and decision support tool for use by healthcare providers caring for patients. The ACT system 102 receives input from various patient care facilities for example, long-term care facilities 104 , acute care facilities 106 , post-acute care facilities 108 and assisted living facilities 110 . Each of these various types of facilities provide different types of care to a patient within their treatment cycle. Long-term care facilities 104 comprise facilities such as nursing homes or extended recovery facilities for patients that are in need of a high level of long term care. Acute care facilities 106 are facilities such as emergency rooms or intensive care units that are used for patients requiring an acute level of physical care. Post-acute care facilities 108 may comprise facilities that patients are transferred to once they leave the acute care facilities. For example, when a patient leaves intensive care and goes into normal hospital care. Finally, assisted living facilities 110 comprise facilities for patients that are in need of some day-to-day medical care but are still substantially able to take care of normal everyday activities on their own. Each of these potential care facilities are only examples of facilities providing input to the ACT system 102 . It will be appreciated that any type of care facility providing medical care for patients and possibly dispensing medications thereto may provide a potential input to the ACT system 102 .
[0014] Individuals who reside in various care facilities need acute care from time to time and will move between care facilities, such as an emergency room to a hospital, and back to long-term care facilities 104 or assisted living facility 110 after discharge. The ACT system 102 manages the individual's medical records and clinical data between the various healthcare facilities because these facilities do not share a common platform or way of managing electronically shared records. The ACT system 102 provides a central medical records database 112 and central clinical data records 114 at a centrally accessible facility. This will enable healthcare providers 116 to obtain records 118 through the ACT system 102 and its medical records database 112 allowing the providers a complete view of the patient's history though a merging of medical data across multiple facilities. Additionally, the ACT system 102 may be configured to generate alerts 122 to the healthcare providers 116 when the system 102 detects treatments or medications that may conflict with each other and cause potential harm to a patient. These alerts are generated against a decision support tool that incorporates an ACT database of clinical and pharmaceutical comparative data that will alert to potential prescription issues based upon clinical, age, medication interactions, or polypharmacy. This allows for a complete review of a patients medication profile prior to transfer to another facility reducing the average number of medications and transcription errors as the patient transfers often includes a new physician and data into a new clinical system.
[0015] Managing patient records and clinical data can be challenging between the various healthcare facilities because they do not have a common platform manner to electronically share records. The ACT system 102 assist in ensuring a consistent continuum of care therapies, medications and general health monitoring across multiple long-term care facilities 104 , assisted living facilities 110 , acute care facilities 106 and post care facilities 108 by importing and storing the data in a common platform that can be shared among the facilities.
[0016] Referring now to FIG. 2 , there is provided a functional block diagram of the ACT system 102 . The ACT system 102 receives input data 204 relating to patient care and medication from various healthcare facilities such as those described with respect to FIG. 1 through an interface engine 201 that will receive the information, convert the data and store in a common format that can be utilized by providers. This information is processed and adapted in a variety of manners within the ACT system 102 . Dosage tracking 203 allows for the tracking of medication dosages provided to a patient that is transferring between the various healthcare facilities. The dosage tracking 203 additionally enables tracking of the inventory of dosages within a medication dispensing system. The ability of the ACT System 202 to integrate to Remote Automated Medication Dispensing Systems within these facilities allows for better formulary control across facilities as well as facilitating medication order reviews so that the medication can be dispensed within minutes rather than the traditional hours it can take when medications have to be prepared and delivered to the facilities. This greatly improves continuity of therapy and allows for complete pharmacy review prior to dispensing.
[0017] The decision support tool module 206 identifies various clinical trends to assist in patient care by comparing clinical and demographic data against information within a data repository 210 . Referring also to FIG. 3 , there is illustrated the various inputs and outputs functionalities of the decision support tool module 206 . The decision support tool 206 incorporates databases of clinical and pharmaceutical comparative data that will alert to potential prescription issues based upon clinical, age, medication interactions, or polypharmacy. The decision support tools 206 receive acute-care data from healthcare facility acute-care databases 302 . This would comprise information from places such as hospice facilities, emergency rooms and the like. The long-term care database 304 provides long-term care data relating to patients that have been kept in nursing homes and other similar types of long-term care facilities. Hospital data is provided from a hospital database 306 including information relating to patient stays within hospital for non-acute care given to a patient. While the above example describes the use of data from particular types of databases relating to acute data, LTC data and hospital data, it should be realized that the decision support tools 206 may utilize numerous other types of data for reaching decisions to assist in patient care.
[0018] The decision support tools 206 perform a number of functions using the data from each of the attached databases. The decision support tools 206 may provide clinical trends analysis 308 . These clinical trends relate to the patient's current and historical diagnosis, medication history, and clinical data providing a complete medication treatment history for the providers. Additionally, the decision support tool database 210 includes clinical data information such as medication dosing guidelines (including elderly), polypharmacy, and medication interactions that will alert provider for possible medication issues. The clinical trends 308 and decision support tools 206 will assist in maintaining the highest possible level care while reducing the number of hospitalizations (readmits) for a patient. The decision support tools 206 may also generate alerts 310 relating to a number of healthcare identifiers which allow the facility/physician to take action by informing the FACILITY physician of potential medication/therapy changes that may cause issues and/or triggering additional monitoring of the patient related to a newly prescribed treatment or medication. The decision support tools 206 allow for a more seamless transition of patients within health networks using data management.
[0019] Thus, as more particularly summarized in FIG. 4 , the decision support tools 206 can utilize acute-care data 402 and ongoing data 404 to generate actionable alerts 406 . The alert generation function 212 provides for actionable alerts as an output 214 in the manner described above. The actionable alerts 406 relate to a number of healthcare identifiers such as wound care 408 , appropriate diagnosis coding 410 , lab and demographic data 414 , and prescriptions 416 . Each of these areas provides the potential for problems with a patient when conflicting treatments or medications are prescribed. The clinical support tools 206 will run resident clinical, vital and demographic data against a data repository to provide the actionable alerts 406 that allow healthcare facility providers and personnel to take actions by informing the physician OF medication or therapy changes, scheduling a clinic visit or for actively monitoring a patient based upon new conditions.
[0020] The ACT system 102 also includes a data management functionality 216 in order to enable the sharing AND CENTRAL MANAGEMENT of patient information between hospitals and other care facilities and for tracking patient data with respect to federal requirements such as 340 -B funding tracking. Referring now also to FIG. 5, 340 -B functions 502 must meet various requirements in order to obtain funding. Items such as data tracking with respect to patients 504 , standardized reports 506 and the tracking of medication dispensing 508 are all required in order to obtain 340 -B funding. The ACT system 102 provides a unique ability to manage the required data tracking and reporting requirements in order to adhere to the 340 -B regulatory requirements by managing the complete data of the ACO (accountable care organization) resident and individual dispensed dose inventory Through the data, the ACT system 102 is able to track each medication dispensed per resident, electronically manage inventory data to the dose level and incorporate required resident demographics and clinical data in order to administer the 340 -B funding across the entire continuum of the ACO.
[0021] The core of the ACT effectively links a patient's acute and LTC data and applies these two the decision support tools 206 to identify clinical trends that will assist in maintaining the highest possible level of care while reducing the number of hospitalizations. The ACT system 102 uses the repository of clinical support tools 208 to run resident clinical and demographic data against the data repository 210 to provide the actionable alerts with respect to the various healthcare identifiers discussed hereinabove.
[0022] The ACT system 102 allows healthcare providers to be more proactive in patient care and partner with the long-term care facilities and assisted living facilities using the systems data integration. Using data management, resident information is shared between the hospital and the other care facilities allowing healthcare providers a complete picture of a patient's history. The ACT system 102 provides a smooth hospital discharge in transition to a care facility by allowing for medications to be dispensed at the hospital and the prescription data entered at the care facility even before the patient has been discharged from the hospital with a complete pharmacy review of the new prescriptions prior to dispensing at the hospital. These and other types of advantages allow for a more centralized database of patient care and medication information to be access by multiple care facilities that are involved in the treatment of a patient and provide a better overall patient care experience.
[0023] It will be appreciated by those skilled in the art having the benefit of this disclosure that this system and method for managing drug dispensing to patients provides a centralized patient and medication management. It should be understood that the drawings and detailed description herein are to be regarded in an illustrative rather than a restrictive manner, and are not intended to be limiting to the particular forms and examples disclosed. On the contrary, included are any further modifications, changes, rearrangements, substitutions, alternatives, design choices, and embodiments apparent to those of ordinary skill in the art, without departing from the spirit and scope hereof, as defined by the following claims. Thus, it is intended that the following claims be interpreted to embrace all such further modifications, changes, rearrangements, substitutions, alternatives, design choices, and embodiments.
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A system for managing patient data for patients moving between a plurality of different patient care facilities includes a first interface for connecting to a plurality of patient care facilities to receive past patient care data. A second interface provides outputs to a current health care provider. A database stores the received past patient care data. A processor includes a set of instructions to configure the processor to monitor the past patient care data with respect to a particular patient and generate an alert to the health care provider over the second interface responsive to a determination that the past patient care data from the plurality of patient care facilities indicates a patient care problem.
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BACKGROUND OF THE INVENTION
[0001] The present invention relates to household appliances and, more particularly, to a rotisserie convection oven including a rotatable cooking drum and method of use, which allows cooking of pre-prepared and frozen foods within such cooking drum with minimal ingestion of cooking oils and cooking oil byproducts in the food items, which is of concern to the health-conscious consumer.
[0002] Portable kitchen countertop ovens with rotisserie mechanisms for cooking food items such as chicken, turkey, roasts and other foodstuffs are known in the prior art. However, such ovens typically utilize a gear driven bar and spit assembly having sharp spit rods whereon the food item is skewered and then placed in the oven for cooking. Such prior art countertop ovens are known to provide rotary cooking containers comprising a housing which is mounted on the rotisserie spit rods to support and rotate the container. Such prior art ovens often utilize tubular heating elements mounted within the cooking chamber of the oven for cooking. Tubular heating elements are constructed from metallic tubing wherein an electrical resistance heating wire is enclosed, which function to radiate heat for cooking within the cooking chamber. The tubular heating elements are normally disposed on the back and/or bottom walls of the cooking chamber and may provide Low and High heat settings for cooking.
[0003] Such a rotary drum for attachment to a prior art rotisserie mechanism has numerous disadvantages. Initially, mounting the rotating drum on a gear driven rotisserie mechanism commonly requires adapting the rotary drum to existing spit rod hardware which necessitates the fabrication of additional components and increased manufacturing complexity and costs.
[0004] In addition, such a prior art rotisserie oven typically includes a rotating basket or an enclosed rotary housing wherein the food items are disposed with added cooking oil and seasonings to effectively baste and stir fry the food items which become saturated with oil during the cooking process thereby adding to the heated cooking oil byproducts ingested by the user.
[0005] Further, such a prior art rotisserie oven typically provides only a single, enclosed cooking chamber wherein the food items are rotated in proximity to a radiant heating element without circulating heated air within the cooking chamber by convection to ensure a more uniform and efficient cooking process of shorter duration.
[0006] Thus, the rotisserie convection oven with a rotatable cooking drum of the present invention has been developed to solve these problems and other shortcomings of the prior art.
DESCRIPTION OF THE PRIOR ART
[0007] U.S. Pat. No. 8,017,167 issued on Sep. 12, 2011, entitled Food Cooking Basket for A Rotisserie Oven discloses a portable oven with a rotisserie mechanism that accommodates a food basket and/or a rotary cooking container. Such cooking container is mounted on the rotisserie spit rod assembly to support and rotate the cooking container, which is a solid-walled (i.e. non-perforated) container designed to retain cooking oils and marinade for cooking food items. This oven utilizes an array of tubular heating rods mounted at the back wall of the cooking chamber of the oven, which can be selectively energized for radiant heating only. This rotisserie oven does not provide a perforated, rotating drum for circulation of heated air by convection through the rotating drum to ensure a uniform cooking process.
[0008] U.S. Pat. No. 7,973,264 issued on Jul. 5, 2011, entitled Toaster Oven with Low-Profile Heating Elements, by the same inventor named herein, discloses an optional rotisserie mechanism and a convection fan to reduce cooking temperature and to shorten cooking cycles. However, this patent does not disclose a rotatable cooking drum of perforated construction wherein foodstuffs are contained for cooking.
[0009] While these devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not disclose the portable convection oven of the present invention including a rotating drum wherein heated air circulates to enhance the cooking process.
SUMMARY OF THE INVENTION
[0010] Accordingly, the present invention is a rotisserie convection oven including a rotatable cooking drum which allows cooking of food items at lower cooking temperatures and shorter cooking cycles thereby eliminating the need for added cooking oils and marinades. The present oven is designed for cooking of pre-prepared or frozen foods such as French fries, fish sticks, chicken nuggets and other foodstuffs resulting in minimal ingestion of cooking oils, grease and cooking derived byproducts of concern to the health-conscious consumer.
[0011] The present rotisserie convection oven provides a kitchen countertop appliance which features an enclosed cooking chamber wherein a rotatable drum is detachably engaged with a rotisserie drive mechanism. The rotisserie drive motor and a convection fan are positioned in a protected control chamber disposed in air transfer communication with the cooking chamber to enable the circulation of heated air within the cooking chamber, which circulates through the rotating drum during the cooking cycle.
[0012] The present rotisserie convection oven provides a rotatable cooking drum which features both end-loading and side-loading of foodstuffs in alternative embodiments for the convenience of the user. The present rotatable cooking drum comprises a food container having a perforated cylindrical wall and/or perforated end caps permitting the circulation of heated air by the convection fan through the rotating drum to maximize cooking efficiency. A plurality of tubular heating elements disposed at predetermined locations within the cooking chamber can be selectively energized and cycled On and Off during the cooking cycle. An interior weir bar or baffle interrupts the continuous tumbling of food items in operation for maximum exposure to the heating elements. The present invention also provides a tool for removing the rotatable drum from the hot oven for the user's convenience.
[0013] There has thus been outlined, rather broadly, the important features of the present invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.
[0014] Those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods, and systems for carrying out the purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
[0015] Other features and technical advantages of the present invention will become apparent from a study of the following description and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The novel features of the present invention are set forth in the appended claims. The invention itself, however, as well as other features and advantages thereof will be best understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures, wherein:
[0017] FIG. 1 is a perspective view of the rotisserie convection oven of the present invention;
[0018] FIG. 2A is a perspective view of the present oven wherein the front door thereof is in an open position showing further details thereof;
[0019] FIG. 2B is a right side elevation view of the present oven wherein the outer wall has been removed for clarification;
[0020] FIG. 3 is a longitudinal cross-section taken along the section line 3 - 3 of FIG. 2A of the present oven showing further details thereof;
[0021] FIG. 4 is a perspective view of the cooking chamber of the present oven wherein the outer housing and door have been removed for clarification;
[0022] FIG. 5 is an exploded perspective view of the components within the present cooking chamber showing further details thereof;
[0023] FIG. 6A is an exploded perspective view of one embodiment of the rotatable drum of the present invention designed for end-loading;
[0024] FIG. 6B is an exploded perspective view of another embodiment of the rotatable drum of the present invention designed for side-loading;
[0025] FIG. 7A is a perspective view of another embodiment of the rotatable drum of the present invention designed for end-loading;
[0026] FIG. 7B is a perspective view of another embodiment of the rotatable drum of the present invention designed for side-loading;
[0027] FIG. 8A is a perspective view of a drum removal tool of the present invention;
[0028] FIG. 8B is a perspective view of a drum removal tool engaged with the rotatable drum illustrated in FIG. 6A ; and
[0029] FIG. 9 is a schematic representation of the electrical components and circuitry of the present rotisserie convection oven.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] With further reference to the drawings there is shown therein an embodiment of a rotisserie convection oven with a rotatable cooking drum in accordance with the present invention, indicated generally at 10 and illustrated in FIG. 1 , although it will be appreciated that the present invention is not limited in scope to this embodiment. The present oven 10 is comprised of an outer housing, indicated generally at 20 , including a front door assembly, indicated generally at 25 , which further includes a viewing window 36 and a door handle 27 for opening and closing door.
[0031] More particularly, outer housing 20 further comprises a front panel 21 , top side 23 , base 24 , side walls 26 , 28 and back wall 22 ( FIG. 2A ). The base 24 of housing 20 is provided with a plurality of feet 32 ( FIG. 2B ), which support the present oven 10 on a kitchen countertop or other working surface.
[0032] A temperature control selector switch 17 a, a function control selector switch 18 a and a timer control switch 19 a are disposed on panel 21 of housing 20 to operate the respective heating controller 17 , function controller 18 and timer 19 components and circuitry ( FIG. 2B ) to regulate the functions of the oven 10 . An indicator light 15 on the front panel 21 is provided for the user's safety and convenience signaling that a cooking cycle is in progress. FIG. 2B also shows the position of the rotisserie drive assembly, indicated generally at 60 and the convection fan assembly, indicated generally at 70 as described hereinafter in further detail.
[0033] In an alternative embodiment of the present oven, a digital control panel (not illustrated) including a touch-screen interface with an integrated control circuit board, which is known in the prior art can be utilized to regulate the functions of the oven.
[0034] As further illustrated in FIGS. 3 and 4 , a cooking chamber 40 comprises opposite sidewalls 41 , 42 , back wall 22 , and top surface 45 wherein a rotatable drum assembly, indicated generally at 75 , is detachably engaged. Chamber sidewalls 41 , 42 are disposed in parallel to housing sidewalls 26 , 28 . Chamber top surface 45 is disposed in parallel to housing base 24 and top side 23 of housing 20 respectively. In the embodiment shown housing back wall 22 defines both the back of housing 20 and also the back of chamber 40 to simplify construction. Similarly, an upper surface of housing base 24 defines both the bottom of housing 20 and the bottom of cooking chamber 40 to simplify construction.
[0035] Housing sidewall 28 , top wall 23 , base 24 , sidewall 42 and a portion of housing back wall 22 including vents 22 a define a control chamber, indicated generally at 90 ( FIG. 3 ). Control chamber 90 encloses the rotisserie drive assembly 60 including a rotisserie motor 68 including electrical circuitry, driveshaft 63 , coupling 59 and stub axle 58 , which engages and rotates drum assembly 75 . It can be seen that control chamber 90 also encloses convection fan assembly 70 including a fan impeller 65 , fan motor 62 including electrical circuitry and fan housing 61 .
[0036] Still referring to FIG. 3 it will be appreciated the present oven 10 includes three pairs of horizontally disposed heating elements 52 , 54 , 56 which are arranged as shown within the cooking chamber 40 . In this embodiment heating elements 52 , 54 , 56 are mounted in close proximity to back 22 , base 24 and top surface 45 of chamber 40 ( FIG. 4 ) in parallel relation and positioned in spaced-apart relation thereto.
[0037] In the embodiment shown in FIGS. 3 and 4 , heating elements 52 , 54 , 56 are tubular type heating elements such as those manufactured under the trade name, CAL-ROD® or other suitable heating elements for this application. CALROD® heating elements 52 , 54 , 56 are typically comprised of stainless steel tubing, which encloses a resistance heating wire (not shown). Such CALROD heating elements 52 , 54 , 56 are well known in the appliance industry and further detailed description thereof is not deemed necessary.
[0038] Heating elements 52 , 54 , 56 are electrically interconnected to the temperature controller 17 , function controller 18 and timer 19 ( FIG. 2B ) to regulate the cooking functions of the oven 10 . Heating elements 52 , 54 , 56 can be selectively energized by using temperature controller knob 17 a and function controller knob 18 a to activate each pair of heating elements separately or in combination to achieve the desired cooking temperature. Function controller 18 provides variable operating modes of the convection motor 62 and rotisserie motor 68 in conjunction with the heating elements 52 , 54 , 56 corresponding to “Broil, Convection, Bake, Rotisserie and Fryer” as illustrated in the electrical schematic in FIG. 9 .
[0039] In a method of the present invention, cooking by convection occurs when the convection function is selected using controller 18 and heated air within oven 10 is forced into the cooking chamber 40 by fan impeller 65 on its output side via outlet vents 64 , 66 ( FIG. 5 ) and is circulated about the cooking chamber. As illustrated in FIG. 3 , fan impeller 65 draws heated air (on its suction side) from cooking chamber 40 , which passes through perforations 77 ( FIG. 5 ) formed in the end caps 75 a, 75 b of the rotating drum 75 as shown by directional arrows 80 . Drawn by fan impeller 65 heated air passes through rotating drum 75 heating food items contained therein and exits via end cap 75 b ( FIG. 6A ) passing into air duct 67 via intake vent 69 ( FIG. 5 ).
[0040] Fan impeller 65 (from its output side) continuously redirects the flow of heated air from duct 67 back into the cooking chamber 40 via outlet vents 64 , 66 as shown in FIG. 3 by directional arrows 85 . Air is circulated around heating elements 52 , 54 , 56 where it is reheated and again passes through the rotating drum 75 via perforations 77 ( FIG. 5 ) and is drawn into inlet vents 69 on the suction side of the fan impeller 65 . By continuously circulating heated air over a tumbling food item positioned within rotatable drum 75 , the present oven 10 can operate at a lower temperature and cook food items more quickly than a comparable prior art rotisserie oven without convection heating.
[0041] In one embodiment shown in FIG. 6A , a drum assembly 75 of the end-loading type comprises a generally cylindrical body member 76 being fabricated of sheet metal whereon end caps 75 a ( FIG. 5 ), 75 b having a plurality of perforations 77 are attached. At least one of such end caps 75 b is removable from the body member 76 by use of operated clamps 86 in order to load pre-prepared or frozen foods such as French fries, fish sticks, chicken nuggets and other similar foodstuffs into the drum assembly 75 for cooking.
[0042] In an alternative embodiment a drum assembly 75 ′ of the side-loading type shown in FIG. 6B comprises a hinged body 76 ′ including upper and lower semi-cylindrical halves 76 a ′, 76 b ′. End caps 75 a ′, 75 b ′ each having a plurality of perforations 77 formed therein are permanently attached to lower body half 76 b ′ by weldment. Body halves 76 a ′, 76 b ′ are connected by a section of piano hinge 71 along the adjacent back edges thereof. The opposite front edge of body halves 76 a ′, 76 b ′ are secured in place by use of friction latches 96 integrated with a handle 97 (as more clearly shown in FIG. 7B ). Latches 96 engage mating catches 96 a installed on the front edge of lower body half 76 b ′ and are opened by manual pressure in order to load pre-prepared or frozen foods and other similar foodstuffs in the drum assembly 75 ′ for cooking.
[0043] Referring to FIG. 7A there is shown another embodiment of rotatable drum assembly 75 ″ of the end-loading type comprising a generally cylindrical body member 76 ″ being fabricated of wire mesh or expanded sheet metal whereon end caps 75 a ″, 75 b ″ having a plurality of perforations 77 are attached by weldment. Similarly, at least one of such end caps 75 b ″ is removable from the body member 76 ″ by use of clamps 86 in order to load foodstuffs into the drum assembly 75 ″ for cooking.
[0044] Another alternative embodiment of a rotatable drum assembly 75 ′ of the side-loading type shown in FIG. 7B comprises a hinged body 76 ′″ including upper and lower semi-cylindrical halves 76 a ′″, 76 b ′″ fabricated of air permeable, wire mesh or expanded sheet metal. End caps 75 a ′″, 75 b ′″ each having a plurality of perforations 77 formed therein are permanently attached to lower body half 76 b ′″ by weldment. Body halves 76 a ′″, 76 b ′″ are connected by a section of piano hinge 71 along the adjacent back edges thereof and secured by weldment. The opposite front edge of body halves 76 a ′″, 76 b ′″ are secured in place by use of friction latches 96 integrated with a handle 97 . It can be seen that body halves 76 a ′″, 76 b ′″ each includes at least one reinforcing strip 79 fabricated of sheet metal to provide structural support for handle 97 , latches 96 and mating catches 96 a and to shield the edges off the wire mesh material. Latches 96 engage mating catches 96 a installed on the front edge of lower body half 76 b ′″ and are opened by manual pressure in order to load pre-prepared or frozen foods and other similar foodstuffs in the drum 75 ′″ for cooking.
[0045] It can be seen that each drum assembly 75 , 75 ′, 75 ″, 75 ′″ includes an interior weir bar or baffle 74 that is permanently attached to and extends the length thereof in parallel relation to axis—A—( FIG. 6A ). Baffle 74 is designed to briefly hold a food item in position as such food item rotates past a given pair of heating elements 52 , 54 , 56 . That is, baffle 74 momentarily interrupts or delays the continuous tumbling of foodstuffs during rotation of a drum assembly 75 , 75 ′, 75 ″, 75 ′″ in the rotisserie mode. Such an interruption in the normal tumbling of foodstuffs within a rotating drum assembly 75 , 75 ′, 75 ″, 75 ′″ has been observed to provide maximum exposure of food items to heating elements 52 , 54 , 56 in operation enabling more efficient cooking and shorter cooking cycles.
[0046] As seen in FIG. 6A a stub axle 58 having a square cross-section projects from mating coupling 59 ( FIG. 5 ) through a hole 55 formed in cooking chamber side wall 42 . Coupling 59 ( FIG. 5 ) includes a square coaxial opening 59 a that is dimensioned to a slip fit condition with stub axle 58 . At an opposite end coupling 59 engages mating driveshaft 63 ( FIG. 3 ) extending from the rotisserie motor 68 . Stub axle 58 is received in a mating receptacle in the end cap 75 b to drive the drum assembly 75 during operation in the rotisserie mode.
[0047] An opposite end cap 75 a of drum assembly 75 receives an extension shaft 78 having a round cross-section ( FIG. 6 ). Extension shaft 78 is received at its proximal end in a mating receptacle (not shown) in the end cap 75 b to enable rotation of drum assembly 75 in operation. A distal end of extension shaft 78 includes a groove 79 , which engages a mating bracket 47 having a slot 47 a adapted to receive groove 79 on the extension shaft ( FIG. 5 ). Bracket 47 is mounted with a fastener (not shown) on a side wall 41 of the cooking chamber 40 ( FIG. 3 ) in alignment with axis—A—of drum assembly 75 and rotisserie drive assembly 60 to ensure rotation with minimal friction.
[0048] Both stub axle 58 and extension shaft 78 include a tool groove 58 a, 78 a respectively for engagement of drum removal tool, indicated generally at 100 , ( FIGS. 8A-8B ) which allows the user to remove drum assemblies 75 , 75 ′, 75 ″, 75 ′″ after a cooking cycle has been completed. Tool 100 is a generally U-shaped in configuration being fabricated from a heavy gauge wire or other suitable material. Tool 100 comprises a cross-member 105 having integrally formed, perpendicular arm members 102 , 103 . The distal ends of each arm member 102 , 103 are bent into J-shaped hook portions 102 a, 103 a as shown in FIG. 8A . A handle 103 for tool 100 is fabricated from a heat-resistant material and is fixedly attached to a midpoint of cross-member 105 for the user's convenience. It will be appreciated that cross-member 105 and arm members 102 , 103 are configured such that hook portions 102 a, 103 a engage tool groves 58 a, 79 a formed in the stub axle 58 and shaft 78 respectively as illustrated in FIG. 8B . Thus, tool 100 enables the user to lift and remove a loaded drum assembly 75 , 75 ′, 75 ″ 75 ′″ from oven 10 when the drum assembly is too hot for direct manual contact by the user.
[0049] The electrical functions of rotisserie oven 10 can be carried out by the standard electromechanical controls as described hereinabove. Alternatively, the electrical functions of the rotisserie convection oven may be carried out by an electronic control panel (not shown) having a touch-based interface with an integrated control circuit board.
[0050] Referring to FIG. 9 there is shown therein a schematic representation of the electrical components and circuitry of the present rotisserie convection oven 10 . Function controller 18 is electrically interconnected with timer 19 , temperature controller 17 , convection fan motor 62 , rotisserie drive motor 68 and heating elements 52 , 54 and 56 . Function controller 18 provides variable operating modes of the convection motor 62 and rotisserie motor 68 in conjunction with the heating elements 52 , 54 , 56 .
[0051] Heating elements 52 , 54 , 56 can be selectively energized by using temperature control selector switch 17 a and function control selector switch 18 a to activate each pair of heating elements separately or in combination to achieve a desired cooking mode (i.e. Broil, Convection, Bake, Rotisserie and Fryer modes) as understood by reference to the schematic drawing of FIG. 9 .
[0052] With reference to electrical specifications, the wattage rating for the present rotisserie convection oven 10 can vary up to 1800 watts depending upon the selected function of the oven.
[0053] The present oven 10 is designed for use with standard residential electrical systems. An electrical cord and plug (not shown) are also provided to connect the present rotisserie convection oven 10 with a standard electrical outlet.
[0054] In accordance with the present invention the drum assemblies 75 , 75 ′, 75 ″, 75 ′″ can be configured to fit various common sizes of commercially available rotisserie ovens and are suitable for retrofitting to such prior art rotisserie ovens to permanently replace conventional rotating baskets and rotisserie bar and spit assemblies.
[0055] Although not specifically illustrated in the drawings, it should be understood that additional equipment and structural components will be provided as necessary and that all of the components described above are arranged and supported in an appropriate fashion to form a complete and operative Rotisserie Convection Oven with Rotatable Drum incorporating features of the present invention.
[0056] Moreover, although illustrative embodiments of the invention have been described, a latitude of modification, change, and substitution is intended in the foregoing disclosure, and in certain instances some features of the invention will be employed without a corresponding use of other features. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of invention.
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A rotisserie convection oven including a rotatable drum assembly which allows cooking of food items therein without added cooking oils is disclosed. The present oven is designed for cooking of pre-prepared or frozen foods with minimal ingestion of cooking oils and residual oil byproducts of concern to the health-conscious consumer. The present oven provides a countertop appliance having an enclosed cooking chamber with tubular heating elements wherein a rotatable drum containing foodstuffs is coupled to a rotisserie drive assembly. An integrated control chamber protects electrical components and encloses a convection fan assembly which is disposed in air transfer communication with the cooking chamber to enable circulation of air across the heating elements and through the rotatable drum during the cooking cycle. In one embodiment the rotatable drum is constructed of wire mesh to permit the continuous circulation of heated air therein to reduce cooking temperatures and shorten the cooking cycle.
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TECHNICAL FIELD
[0001] The present invention relates generally to wireless network communication. More particularly, the invention relates to improved systems and techniques for multi-cell coordinated scheduling.
BACKGROUND
[0002] Efficiency in wireless network communication is an important objective, becoming more and more important as the number of users and their demands for service continue to increase. Network operators wish to minimize the infrastructure they must provide. In addition, the frequency bands dedicated to wireless network communication are a finite and valuable resource, and network operators are constantly working to use this resource efficiently in order to prevent the available frequencies from becoming oversaturated. If frequencies are oversaturated, network elements will interfere with one another. For example, transmission by one base station may interfere with transmission by an adjacent base station. In order to prevent interference. Network operators may take into account the presence of nearby transmitters in making scheduling decisions, and transmitters (such as base stations) may coordinate their transmissions so as to avoid interference with one another.
SUMMARY
[0003] In one embodiment of the invention, an apparatus comprises at least one processor and memory storing a program of instructions. The memory storing the program of instructions is configured to, with the at least one processor, cause the apparatus to at least, in response to a control assertion request to allow a controlling entity to control coordinated radio transmission by the apparatus, respond with an acceptance or denial of the request and, if the response is an acceptance, perform coordinated transmission under control of the controlling entity.
[0004] In another embodiment of the invention, a method comprises, in response to a control assertion request to allow a controlling entity to control coordinated radio transmission by a base station, responding with an acceptance or denial of the request and, if the response is an acceptance, performing coordinated transmission under control of the controlling entity.
[0005] In another embodiment of the invention, a non-transitory computer readable medium stores a program of instructions. Execution of the program of instructions by at least one processor configures an apparatus to at least in response to a control assertion request to allow a controlling entity to control coordinated radio transmission by the apparatus, respond with an acceptance or denial of the request and, if the response is an acceptance, perform coordinated transmission under control of the controlling entity.
[0006] In another embodiment of the invention, an apparatus comprises at least one processor and memory storing a program of instructions. The memory storing the program of instructions is configured to, with the at least one processor, cause the apparatus to at least send a control assertion request to a base station, requesting control of coordinated radio transmission by the base station and, in response to acceptance of the request by the base station, send one or more requests to the base station to mute transmission.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 illustrates a wireless network according to an embodiment of the present invention;
[0008] FIGS. 2-6 illustrate signaling between and operations of elements carrying out embodiments of the present invention;
[0009] FIG. 7 illustrates details of elements according to an embodiment of the present invention; and
[0010] FIG. 8 illustrates a process according to an embodiment of the present invention.
DETAILED DESCRIPTION
[0011] Embodiments of the present invention address improvements to coordinated multipoint communication—specifically, multi-cell coordinated scheduling. Various approaches to multi-cell coordinated scheduling are in development or in use in cellular communication systems. These include centralized and decentralized approaches. Base stations may coordinate transmission order to avoid interference with one another. One mechanism is to mute transmission requiring particular resources or at a particular time (with muting being defined as a zero-power transmission or interval), while another mechanism is to transmit at reduced power in particular resources or time periods. In a decentralized approach to coordinated scheduling, a cell, which may be represented by a base station, makes its own decision on muting (that is, refraining from transmitting or scheduling transmission from one or more of its user devices). In networks operating according to standards of the third generation partnership project (3GPP), 3GPP long term evolution (LTE) and 3GPP LTE-advanced (LTE-A), a base station may be implemented as an eNodeB (eNB), with an eNB serving user equipments (UEs) within its coverage area.
[0012] In a network or portion of a network that follows a centralized approach, a central entity makes decisions about whether a particular base station should mute, and issues an appropriate request to the base station (such as an eNB). A base station may be designed for centralized control (such a base station may be referred to for convenience as a centrally controlled base station) or may be designed for decentralized operation (such a base station may be referred to as an autonomous base station —meaning that the base station's coordination decisions are autonomous). A centrally controlled base stations will perform coordination as directed by the central entity, and an autonomous base station will generally ignore requests by the central entity. In some cases, a base station may respond to requests from a central entity during most of its operation, but, under some circumstances, ignore requests and make its own decisions. Such circumstances may include, for example, handing of high priority traffic using specified resources. Such a base station may be referred to for convenience as a partially autonomous base station. The various elements participating in and controlling coordinated transmission may be referred to as nodes, and one or more of the nodes may conveniently be referred to as an independent node, which may control and direct other nodes, but which may not itself serve a user device. In one or more embodiments of the invention, the central entity may be an independent node.
[0013] In an environment in which centrally controlled base and autonomous base stations are both present, such mixing may lead to conflicts, as a central entity sends requests to both autonomous base stations and centrally controlled base stations, and the two types of base stations conflict because the behavior of the autonomous base station is unpredictable.
[0014] In one or more embodiments of the invention, therefore, a unified signaling procedure is employed that encompasses centrally controlled and autonomous coordination. Various embodiments of the unified signaling procedure prevent conflicts involving interaction between a central entity and an autonomous base station; interaction between a central entity and a centrally controlled base station; interaction between an autonomous base station and a centrally controlled base station; interaction between two autonomous base stations; and interaction between a central entity and a centrally controlled base station that behaves autonomously with respect to specified resources.
[0015] FIG. 1 illustrates a network 100 according to an embodiment of the present invention. The network 100 comprises base stations implemented as eNBs 102 A and 102 B, defining cells 104 A and 104 B, respectively, and communicating with a central entity 106 . The eNBs 102 A and 102 B serve a plurality of UEs 108 A- 108 E, which may move between cells or be turned off or otherwise disconnected to the network. Other UEs may be introduced to the network as they are turned on or moved in from elsewhere. One or more network nodes, such as the eNBs 102 A and 102 B or the central entity 106 , may engage in coordinated scheduling in order to reduce interference.
[0016] In one or more embodiments of the invention, network nodes involved in such coordination negotiate with one another. In one example, a requesting node (such as the central entity 106 ) needing to scheduling decisions for a responding node (such as one of the eNBs 102 A or 102 B) indicates to the second node that it needs to make such decisions and issue requests to the second node to take such action. The second node responds to the first node by indicating that it will or that it will not accept such requests. It will be noted that whether the responding node is to indicate acceptance or denial can be based on any criteria desired. For example, the responding node may indicate acceptance to a request from a first requesting node, or may indicate denial to a second responding node, or may generally accept requests but may deny requests and make decisions autonomously with respect to specific traffic categories or resources. For example, either the requesting or the responding node, or both, may assign specific physical resource blocks (PRBs) to a high priority or protected category, and the requesting node may decline to request, or the responding node may decline to accept, centrally controlled scheduling with respect to those blocks.
[0017] If a response is a denial, various embodiments of the invention provide for mechanisms to specify which node's indications will take priority—that is, whether denials will be accepted. If the requesting node is given priority, the responding node will be forced to accept its requests, and if the responding node is given priority, its denials will be accepted. It will be recognized that assignment of priority can be based on any criteria desired, and can change. For example, nodes can be ranked, so that a first central entity (for example) may be able to override a denial by a specific responding node, while a second central entity may be unable to override a denial by the same responding node. Responding nodes may be similarly ranked. Alternative approaches may involve the assignments of weightings to nodes, so that a higher weighted node may be given priority over a lower weighted node. Priority decisions can be made per-transaction, or criteria may be defined so that nodes have higher priority with respect to particular resources or traffic categories than with other resources or traffic categories. For example, specific physical resource blocks (PRBs) may belong to a high priority or protected category, with higher weighting assigned to use of those blocks by the responding node.
[0018] In one or more embodiments of the invention, various entities, such as the eNB 102 A, the eNB 102 B, and the central entity, communicate as governed by a specified signaling framework designed to provide for support of both centralized and distributed coordination. By pre-negotiation or operation and maintenance configuration, the decision maker for coordination interactions is specified. Selection of the decision maker can be accomplished according to any criteria desired—for example, identifying an entity as dominant, choosing a dominant entity based on conditions such as traffic levels, or specifying decision makers for each radio resource unit (for example, frequency domain resources such as physical resource blocks (PRBs) or resource block groups (RBGs), or time domain resources such as transmission time intervals (TTIs). As described in greater detail below, coordination may be managed in a hand-shaking coordination request (request and response). The decision maker may be the node making the request or the node receiving the request.
[0019] For radio resource units (for example, individual PRBs or RBGs, or alternatively across the whole bandwidth), if the requesting entity is the decision maker, the receiving eNB must respond as requested.
[0020] In cases in which the eNB receiving a request has the final authority, the receiving eNB may reject the request if needed: for example, making best efforts to fulfill a request but not guaranteeing that the request will be fulfilled. Such an approach is useful if a radio resource has been reserved for a specific purpose—for example, if an eNB has configured an SPS transmission on specified PRBs, or PRBs have been configured as a physical download control channel. In another typical case, the receiving eNB may have been designed for autonomous or decentralized operation, making its own determination of its coordination action (such as muting) so that it would not generally accept requests from another node. As discussed in greater detail below, relative priorities between nodes can be adjusted based on factors such as current load and traffic type. A network such as the network 100 can therefore exist as a hybrid between centralized and autonomous communication.
[0021] FIG. 2 illustrates a diagram 200 presenting signaling and operations by and between a requesting node, taking the form of a central entity 202 , and a responding node, taking the form of an eNB 204 . The central entity 202 issues a control assertion message 206 , notifying the eNB 204 of its intention to make centrally-controlled scheduling requests—either in general, or on a more limited basis, such as per-PKB or per-RBG, or with most resources being subject to central control, but with specified resources being managed autonomously. The eNB 204 responds to the control assertion message 206 with a control acceptance message 208 , indicating its agreement to accept centrally controlled scheduling requests—again, either in general or on a more limited basis either general or on a more limited basis. The central entity may then make requests 210 to the eNB 204 , which may then respond with acknowledgements 212 . At an appropriate subsequent time, the eNB 204 may send a control acceptance update message 214 to the central entity 202 , indicating a modification of the requests to which it will respond. At further appropriate subsequent times, the central entity 202 may send a control assertion update message 216 to the eNB 204 , indicating a change in the nature of requests it will make (for example, changing the resources that may be subject to a request. The eNB 204 may respond with a modification acceptance message 218 .
[0022] FIG. 3 illustrates a diagram 300 , showing interactions between and operations by the central entity 202 and the eNB 204 , with the eNB 204 initiating the negotiation. The eNB 204 sends a control acceptance readiness message 306 to the central entity 202 , indicating agreement to accept requests. The central entity 202 responds with a control assertion readiness message 308 . The central entity 202 then proceeds to make requests 310 , and the eNB 204 responds with acknowledgements 312 . As needed, the eNB 204 sends a control acceptance update message 314 , indicating a change to its agreement to accept requests, and the central entity 202 responds with an acknowledgement 316 . Similarly, as needed, the central entity 202 sends a control assertion update message 318 , and the eNB 204 responds with an acknowledgement 320 .
[0023] FIG. 4 illustrates a diagram 400 presenting operations of and messages between a central entity 402 and an eNB 404 , designed for decentralized operation. The central entity 402 sends a control assertion message 406 to the eNB 404 , which responds to the control assertion message 406 with a control decline message 408 . The central entity 402 makes a determination 410 of its priority with respect to the eNB 404 , and if ( 412 ) the central entity 202 has a higher priority, it sends an override message 414 to the eNB 404 , which responds with an override acknowledgement 416 , and then sends requests 418 which are then responded to with acknowledgements 420 . If ( 422 ) the central entity 202 has a lower priority than does the eNB 204 , the central entity 402 makes no further decisions regarding actions to be performed by the eNB 204 .
[0024] FIG. 5 illustrates a diagram 500 presenting operations of and messages between a first enB 502 and a second eNB 504 , with the first eNB 502 being designed for centralized operation and the second eNB 504 being designed for decentralized operation. The first eNB 504 sends a control acceptance message 506 , indicating a willingness to accept control, but the second eNB 506 responds with a control assertion decline message 508 , indicating an unwillingness to exercise control. The second eNB 504 makes ( 510 ) no attempt to exert control and the first eNB optionally seeks ( 512 ) another entity for centralized control.
[0025] FIG. 6 illustrates a diagram 600 presenting operations of and messages between a first enB 602 and a second eNB 604 , with both of the eNBs 602 and 604 being designed for decentralized operation. The first eNB 604 sends a control assertion rejection message 606 , indicating an unwillingness to assert control, and the second eNB 606 responds with a control rejection message 608 , indicating an unwillingness to accept control.
[0026] Reference is now made to FIG. 7 for illustrating a simplified block diagram of a base station, such an eNB 700 and a user device, such as a UE 750 , suitable for use in practicing exemplary embodiments of this invention. In FIG. 7 an apparatus, such as the eNB 700 , is adapted for communication with other apparatuses having wireless communication capability, such as the UE 750 .
[0027] The eNB 700 includes processing means such as at least one data processor (DP) 1204 , storing means such as at least one computer-readable memory (MEM) 706 storing data 708 and at least one computer program (PROG) 710 or other set of executable instructions, communicating means such as a transmitter TX 712 and a receiver RX 714 for bidirectional wireless communications with the UE 750 via one or more antennas 716 .
[0028] The UE 750 includes processing means such as at least one data processor (DP) 754 , storing means such as at least one computer-readable memory (MEM) 756 storing data 758 and at least one computer program (PROG) 760 or other set of executable instructions, communicating means such as a transmitter TX 762 and a receiver RX 764 for bidirectional wireless communications with the eNB 1200 via one or more antennas 766 .
[0029] At least one of the PROGs 710 in the eNB 700 is assumed to include a set of program instructions that, when executed by the associated DP 704 , enable the device to operate in accordance with the exemplary embodiments of this invention, as detailed above. In these regards the exemplary embodiments of this invention may be implemented at least in part by computer software stored on the MEM 706 , which is executable by the DP 704 of the eNB 700 , or by hardware, or by a combination of tangibly stored software and hardware (and tangibly stored firmware). Similarly, at least one of the PROGs 760 in the UE 750 is assumed to include a set of program instructions that, when executed by the associated DP 754 , enable the device to operate in accordance with the exemplary embodiments of this invention, as detailed above. Electronic devices implementing these aspects of the invention need not be the entire devices as depicted at FIG. 1 or FIG. 7 or may be one or more components of same such as the above described tangibly stored software, hardware, firmware and DP, or a system on a chip SOC or an application specific integrated circuit ASIC.
[0030] In general, the various embodiments of the UE 750 can include, but are not limited to personal portable digital devices having wireless communication capabilities, including but not limited to cellular telephones, navigation devices, laptop/palmtop/tablet computers, digital cameras and music devices, and Internet appliances.
[0031] Various embodiments of the computer readable MEM 706 and 756 include any data storage technology type which is suitable to the local technical environment, including but not limited to semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory, removable memory, disc memory, flash memory, DRAM, SRAM, EEPROM and the like. Various embodiments of the DP 704 and 754 include but are not limited to general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and multi-core processors.
[0032] FIG. 8 illustrates a process 800 according to an embodiment of the present invention. At block 802 , a first and a second device engage in negotiation to determine whether the first device will control, or will be controlled by, the second device with respect to coordinated transmission. The devices may be, for example, a central entity or a base station, and the negotiation may take the form of an assertion of control and an acceptance or denial, a notification that one device is ready to accept control and an acceptance or denial of assertion or control, or a notification that a device is not ready to accept control, and an acknowledgement. At block 804 , coordination proceeds according to the negotiation.
[0033] While various exemplary embodiments have been described above it should be appreciated that the practice of the invention is not limited to the exemplary embodiments shown and discussed here. Various modifications and adaptations to the foregoing exemplary embodiments of this invention may become apparent to those skilled in the relevant arts in view of the foregoing description.
[0034] Further, some of the various features of the above non-limiting embodiments may be used to advantage without the corresponding use of other described features.
[0035] The foregoing description should therefore be considered as merely illustrative of the principles, teachings and exemplary embodiments of this invention, and not in limitation thereof.
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Systems and techniques for negotiated control of multipoint coordination. A first device (such as a central entity or base station) signals a second device regarding its desire to assert control over, or readiness to accept control by, the second device, with respect to coordinated radio transmission. The negotiation may include, for example, acceptance of control, rejection of control, specification of resources subject to or exempt from control, and priority-based decisions to override or refrain from overriding rejections. Coordinated transmission is then conducted based on the outcome of the negotiation.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of and priority to U.S. Provisional Application No. 61/728,267, filed Nov. 20, 2012, and European patent application No. 12 193 434.3, filed Nov. 20, 2012, the entire disclosures of which are incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to a method and apparatus for forming a curved prepreg strip or sheet, especially for use in the fabrication of a fibre-reinforced composite component, particularly one with a complex geometry. This invention also relates to a prepreg strip or sheet formed by such a method and/or apparatus, as well as to a fibre-reinforced composite component which incorporates such a prepreg strip or sheet.
BACKGROUND
Currently, composite parts that are straight or only slightly bent can be produced by manual or semi-automated processes. The production of curved composite parts, however, represents a great challenge. One of the main problems in this regard is the draping of a prepreg strip or sheet over a curved profile because the different lengths of the curved geometry between a radially inner region and a radially outer region typically result in wrinkles and/or fibre distortions in the prepreg strip or sheet, as well as gaps between prepreg strips or sheets. To address these problems, techniques including the cutting of the prepreg strips and sheets to minimize wrinkles and distortions have been employed, but these techniques are extremely time consuming.
SUMMARY
It is therefore an idea of the present invention to provide a new and improved technique for overcoming the problem of wrinkles, distortions and/or gaps in a prepreg strip or sheet to be draped over a curved profile in the fabrication of a fibre-reinforced composite component.
According to one aspect, therefore, the invention provides a method of forming a curved prepreg strip or sheet, especially for use in fabricating a composite component, the method comprising the steps of providing a strip or sheet of prepreg material having reinforcing fibres; and drawing or conveying the strip or sheet of prepreg material in a travel direction, wherein the strip or sheet is drawn or conveyed in the travel direction at a speed which differs across a width of the strip or sheet transverse to the travel direction.
By varying the speed of the prepreg strip or sheet across a width thereof transverse to the travel direction, such that different portions of the strip or sheet across its width are drawn or conveyed in the travel direction at different speeds it becomes possible to modify the orientation of the fibres in the strip or sheet of prepreg material, and thereby modify or adapt the geometry of the strip or sheet to provide a curved form. In this manner, it has been found that the strip or sheet of prepreg material can be specifically suited to be draped over curved profiles in the production of a fibre-reinforced composite component without creating significant wrinkles, distortions, or gaps in the lay-up of the prepreg material.
In a preferred embodiment of the invention, the width of the strip or sheet across which the speed in the travel direction differs is substantially perpendicular to or at right angles to the travel direction. In this regard, the strip or sheet of prepreg material is typically elongate and defines a major surface that is substantially flat and planar with a leading edge, opposite lateral sides and a trailing edge. The width of the strip or sheet is typically the distance between the lateral sides. A thickness of the strip or sheet is generally small; that is the prepreg material is thin and may comprise only a single layer or perhaps just a few layers of fibres. The fibres of the prepreg may be unidirectional, or they may be multi-directional.
In a preferred embodiment, the strip or sheet is drawn or conveyed in the travel direction at a speed that varies across the width of the strip or sheet from a first higher speed at a first lateral side to a second lower speed at a second lateral side of said strip or sheet. In particular, the speed preferably varies substantially continuously across the width of the strip or sheet from the first speed at the first lateral side to the second speed at the second lateral side, and preferably in a linear relationship with distance across the width of the strip or sheet. By virtue of the fact that the speed of the strip or sheet in the travel direction varies across its width substantially continuously, it is thus possible to achieve substantially uniform modification in orientation of the fibres in the prepreg material.
By pre-selecting a maximum speed difference across the width of the strip or sheet between the first speed at the first lateral side and the second speed at the second lateral side, it is possible to predetermine the degree of modification to the orientation of the fibres in the prepreg material and, in turn, the extent of modification to the geometry of the strip or sheet; e.g. the amount of curvature imparted to the strip or sheet. For a higher degree of curvature, for example, the maximum speed difference across the width of the strip or sheet is preferably in a ratio of greater than or equal to about 2:1, e.g. 3:1. For a lower degree of curvature, on the other hand, the maximum speed difference across the width of the strip or sheet is preferably in a ratio of less than about 2:1, e.g. in the range of 1.1:1 to 1.9:1.
In a particularly preferred embodiment, the step of drawing or conveying includes: feeding and/or rolling the strip or sheet of prepreg material in the travel direction between a pair of conical rollers that are driven at substantially the same rotational speed, i.e. in counter rotation. In this regard, the strip or sheet of prepreg material is preferably drawn or conveyed in the nip of the pair of conical rollers, whereby one of said pair of rollers contacts an upper surface of the strip or sheet of prepreg material across said width thereof and the other of said rollers contacts a lower surface of the strip or sheet of prepreg material across said width thereof. The travel direction is determined by a tangential velocity of the rollers at the contact with the strip or sheet of prepreg material in the nip. Both of the rollers of the pair preferably have substantially the same geometry, including a circular cross-section which tapers axially across the width of the strip or sheet at a substantially constant angle from a larger diameter at one axial end on the first lateral side to a smaller diameter at an opposite axial end on the second lateral side.
By selecting a regular frustro-conical geometry for each of the pair of rollers, the desired continuity in the variation of the drawn or conveyed speed of the strip or sheet across the width thereof is provided. Furthermore, by pre-selecting the respective larger and smaller diameters of the respective ends of each of the rollers, a particular speed difference across the width of the strip or sheet of prepreg material is able to be predetermined.
In a preferred embodiment, the method may include the step of feeding and/or rolling the strip or sheet of prepreg material in the travel direction between the pair of conical rollers a number of times or, in the alternative, between a series of multiple pairs of conical rollers. In this way, the strip or sheet may undergo a repeated treatment or processing by the rollers to increase or enhance spreading or reorientation of the reinforcing fibres in the prepreg, thereby increasing the curvature of the strip or sheet.
In a preferred embodiment, the method further comprises the step of heating the strip or sheet of prepreg material before and/or during the drawing or conveying step. In this regard, the prepreg material typically includes a polymer resin, the viscosity of which is influenced by temperature. Accordingly, by heating the strip or sheet of prepreg material, the strip or sheet will generally become softer and less stiff, which in turn enhances its ease of processing in the above method.
By processing strips or sheets of prepreg material with the method described above, the invention is able to form curved prepreg strips or sheets in a highly reproducible manner. The curvature of a strip or sheet can be tailored to a particular geometry required such that the problems of wrinkles, fibre distortions and/or gaps in the production of a composite are avoided without time-consuming prior art cutting techniques. Furthermore, it is possible to form not only uni-directional prepregs, but also to customize the fibre orientation of the prepreg material, such as ±45°.
According to another aspect, the present invention provides an apparatus for forming a curved prepreg strip or sheet, especially for use in fabricating a composite component, the apparatus comprising: a mechanism for drawing or conveying a strip or sheet of prepreg material in a travel direction, wherein the mechanism is configured to draw or convey the strip or sheet of prepreg material in the travel direction at a speed which differs across a width of the strip or sheet transverse to the travel direction.
In a preferred embodiment of the invention, the mechanism is configured to draw or convey the strip or sheet of prepreg material in the travel direction at a speed that varies over or across the width of the strip or sheet from a first speed at a first lateral side to a second speed at a second lateral side of that strip or sheet. Preferably, the speed varies substantially continuously across the width of the strip or sheet from the first speed at the first lateral side to the second speed at the second lateral side. The variation of the speed in the travel direction across the width of the strip or sheet may, for example, vary linearly from the first speed at the first lateral side to the second speed at the second lateral side.
As noted above, in a preferred embodiment the mechanism may include a pair of conical rollers configured to be driven at substantially the same rotational speed. The strip or sheet of prepreg material is thus drawn or conveyed in the nip of the pair of conical rollers, whereby one of the said pair of rollers contacts an upper surface of the strip or sheet of prepreg material across the width thereof and the other of said rollers contacts a lower surface of the strip or sheet of prepreg material across the width thereof. Particularly preferably, both of the rollers have substantially the same geometry, including a circular cross-section that tapers in an axial direction at a substantially constant angle from a larger diameter at one axial end to a smaller diameter at an opposite axial end.
In a preferred embodiment, the mechanism comprises multiple pairs of the conical rollers arranged serially in the travel path of the strip or sheet of prepreg material.
In a preferred embodiment, the apparatus further comprises at least one heating device for heating the strip or sheet of prepreg material as it is drawn or conveyed along the travel direction. Particularly preferably, the apparatus may include a plurality of heating devices arranged for heating the strip or sheet of prepreg material over its travel path through the apparatus as it is drawn or conveyed in the travel direction.
According to a further aspect, the present invention provides a curved prepreg strip or sheet formed by a method and/or by an apparatus of the invention as described according to any one of the embodiments above. Thus, the invention may provide a strip or sheet of prepreg material comprising a plurality of reinforcing fibres in a matrix of a non-hardened polymer resin, wherein the fibres have been spread or re-oriented, e.g. by rolling, to provide the strip or sheet with a curved geometry. In this regard, the curved geometry is preferably substantially within a plane of the strip or sheet itself. In yet another aspect, the invention provides a fibre-reinforced composite component that incorporates such a strip or sheet of prepreg material.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention and the advantages thereof, exemplary embodiments of the invention are explained in more detail in the following description with reference to the accompanying drawings, in which like reference characters designate like parts and in which:
FIG. 1 is a schematic perspective view of an apparatus for forming a curved prepreg strip or sheet according to an embodiment of the invention;
FIG. 2 is a schematic illustration of the fibre spreading in a prepreg strip or sheet formed according to the invention;
FIG. 3 is a schematic illustration of variation possible in forming a prepreg strip or sheet in accordance with the invention;
FIG. 4 is a side view of an apparatus for forming a curved prepreg strip/sheet according to another embodiment of the invention;
FIG. 5 is a perspective view of the apparatus in FIG. 4 ;
FIG. 6 is a plan view of an apparatus for forming a curved prepreg strip or sheet according to a further embodiment of the invention; and
FIG. 7 is a perspective view of the apparatus in FIG. 6 .
The accompanying drawings are included to provide a further understanding of the present invention and are incorporated in and constitute a part of this specification. The drawings illustrate particular embodiments of the invention and together with the description serve to explain the principles of the invention. Other embodiments of the invention and many of the attendant advantages of the invention will be readily appreciated as they become better understood with reference to the following detailed description.
It will be appreciated that common and well understood elements that may be useful or necessary in a commercially feasible embodiment are not necessarily depicted in order to facilitate a more abstracted view of the embodiments. The elements of the drawings are not necessarily illustrated to scale relative to each other. It will further be appreciated that certain actions and/or steps in an embodiment of a method may be described or depicted in a particular order of occurrences while those skilled in the art will understand that such specificity with respect to sequence is not necessarily required. It will also be understood that the terms and expressions used in the present specification have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study, except where specific meanings have otherwise been set forth herein.
DETAILED DESCRIPTION
With reference to FIG. 1 of the drawings, an apparatus 1 for forming a curved prepreg strip or sheet is illustrated in a simplified abstract embodiment. This apparatus 1 comprises a mechanism 2 for drawing and conveying a strip or sheet S of prepreg material in a travel direction T. In this embodiment, the strip or sheet S may be considered to be a substantially flat strip or slat of little thickness. The slat S of prepreg material comprises reinforcing fibres F (e.g. glass fibres or carbon fibres) which are arranged or arrayed in a matrix of a non-hardened polymer resin. The fibres F may, for example, be arranged uni-directionally and parallel with one another in the slat S transverse or perpendicular to a length direction of the slat (as shown in FIG. 2 ) or may be arranged multi-directionally in the slat, including in the length direction.
In this particular embodiment, the mechanism 2 comprises a pair of frustro-conical rollers 3 , 4 arranged adjacent or next to one another for counter rotation and defining a small gap or nip 5 there-between that is configured to receive and to convey the strip or sheet S of prepreg material between the driven rollers 3 , 4 . Each of the upper and lower rollers 3 , 4 has substantially the same geometrical configuration, being symmetrical about its central rotational axis X and having a circular cross-section which tapers in an axial direction at a substantially constant angle from a larger diameter d1 at a first axial end 6 to a smaller diameter d2 at an opposite, second axial end 7 .
Each axis X of the rollers 3 , 4 extends at approximately 90° to the travel direction T and the strip or sheet S of prepreg material is drawn or conveyed in the nip 5 of the pair of conical rollers 3 , 4 such that the upper roller 3 contacts an upper surface of the slat S across a width w thereof, while the lower roller 4 contacts a lower surface of the slat S of prepreg material across that width. When the pair of conical rollers 3 , 4 are driven in counter-rotation at essentially the same rotational speed n about their respective rotational axes X, the slat S is drawn or conveyed by the rollers 3 , 4 in the travel direction T at a speed which differs across the width w of the slat S transverse to the travel direction T. In particular, because the diameter of each conical roller 3 , 4 changes linearly from the maximum diameter d1 at the first end 6 of the roller proximate a first lateral side s1 of the slat S to the minimum diameter d2 at the second end 7 of the roller proximate a second lateral side s2 of the slat S, the speed imparted to the slat S between the two rollers 3 , 4 varies continuously (with roller diameter) across the width w of the slat. As a result, the first lateral side s1 proximate the first axial end 6 of rollers 3 , 4 is drawn or conveyed at a substantially higher speed in the travel direction than the second lateral side s2 of the strip or sheet S.
Consequently, as is particularly clearly visible from FIG. 2 , the ends of the fibres F of the prepreg material that extend transversely across the slat S (i.e. in the width direction) are drawn further apart from one another at the first lateral side s1 compared to the ends of those fibres F at the second lateral side s2. That is, FIG. 2 of the drawings shows the transversely extending fibres F of the slat S both before (on left-hand side) and after (on right-hand side) the slat S has passed through the rollers 3 , 4 . The arcuate or curved form of the slat S generated by the frustro-conical rollers 3 , 4 is clearly evident both in FIG. 1 and in FIG. 2 .
With reference now to FIG. 3 of the drawings, the influence or impact of the respective diameters of the first and second ends 6 , 7 of the conical rollers 3 , 4 are illustrated by two examples. In the first example (on left-hand side) of FIG. 3 , the diameter d1 of the first end 6 is only somewhat larger than the diameter d2 of the second end 7 of each roller 3 , 4 in the pair (e.g. d1 in the range of about 1.1 to 1.5 times the size of d2; i.e. d1>d2). This configuration produces an only moderately curved prepreg strip or slat. In the second example (on the right-hand side) of FIG. 3 , by contrast, d1 is substantially greater than d2 (e.g. d1 is about three times the size of d2; i.e. d1>>d2). This configuration creates a significantly more highly curved prepreg strip or slat S.
Referring now to FIGS. 4 and 5 of the drawings, another less abstract embodiment of an apparatus 1 according to this invention is illustrated. The apparatus 1 of this embodiment again includes a mechanism 2 having a pair of frustro-conical rollers 3 , 4 arranged adjacent to one another and mounted for counter-rotation about the respective axes X. In this regard, each of the rollers 3 , 4 is supported on a frame structure 8 and is rotationally mounted on a respective shaft 9 . Also supported on the frame structure 8 is a supply roll 10 of the strip or sheet S of prepreg material for feeding between the two rollers 3 , 4 . A travel path P of the strip S through the apparatus 1 is particularly apparent from FIG. 4 and extends from the supply roll 10 , around the lower roller 4 , into the nip 5 and between the two rollers 3 , 4 , and then back over the upper roller 4 . Arrow heads along the travel path P also indicate the travel direction T. As was the case with the embodiment of FIG. 1 , the pair of rollers 3 , 4 are driven in counter rotation and impart a speed to the strip or slat S in between the two rollers 3 , 4 which varies across the width w of that strip or slat. As the ratio of the diameters d1, d2 of the first and second ends 6 , 7 of each conical roller 3 , 4 is relatively small in this case (e.g. d1:d2=about 1.2:1), the amount or degree of curvature imparted to the strip or slat S is correspondingly low.
Another embodiment of an apparatus 1 according to the present invention is illustrated in FIGS. 6 and 7 of the drawings. In this embodiment, the frame structure 8 of the apparatus 1 is considerably larger than the previous embodiment and supports a plurality of pairs of the conical rollers 3 , 4 spaced apart from one another in series along the travel path P of the strip or sheet S of prepreg material. The serially arranged pairs of rollers therefore progressively impart an increasing degree of curvature to the prepreg strip S as it progresses through the apparatus 1 on the travel path P. Also supported on the frame structure 8 and arranged distributed along the travel path P between the respective pairs of rollers 3 , 4 are three heating devices 11 (e.g. radiant heaters) for heating the strip S as it travels through the apparatus 1 . In this regard, the heating devices 11 soften the polymer matrix of the prepreg material rendering the strip or slat S less stiff and more easily workable between the conical rollers 3 , 4 . As an alternative to using one or more individual heating devices 11 for discrete application of localised heat to the strip S, it will be appreciated that the apparatus 1 of the invention could be installed in a chamber or room having one or more heating unit for a controlled ambient temperature.
Although specific embodiments of the invention have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations exist. It should be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing summary and detailed description will provide those skilled in the art with a convenient road map for implementing at least one exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their legal equivalents. Generally, this application is intended to cover any adaptations or variations of the specific embodiments discussed herein.
In this document, the terms “comprise”, “comprising”, “include”, “including”, “contain”, “containing”, “have”, “having”, and any variations thereof, are intended to be understood in an inclusive (i.e. non-exclusive) sense, such that the process, method, device, apparatus or system described herein is not limited to those features or parts or elements or steps recited but may include other elements, features, parts or steps not expressly listed or inherent to such process, method, article, or apparatus. Furthermore, the terms “a” and “an” used herein are intended to be understood as meaning one or more unless explicitly stated otherwise. Moreover, the terms “first”, “second”, “third”, etc. are used merely as labels, and are not intended to impose numerical requirements on or to establish a certain ranking of importance of their objects.
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The present invention relates to a method of forming a curved prepreg strip or sheet, especially for use in fabricating a composite component. The method includes providing a strip or sheet of prepreg material having reinforcing fibers and drawing or conveying the prepreg material in a travel direction, wherein the material is drawn or conveyed in the travel direction at a speed which differs across a width of the strip or sheet transverse to the travel direction. Similarly, the invention relates to an apparatus for forming a curved prepreg strip or sheet, having: a mechanism for drawing or conveying a strip or sheet of prepreg material in a travel direction, wherein the mechanism is configured to draw or convey the strip or sheet of prepreg material in the travel direction at a speed which differs across a width of the strip or sheet transverse to the travel direction.
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CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of application Ser. No. 522,293, filed 8/11/83, now U.S. Pat. No. 4,685,878.
BACKGROUND OF THE INVENTION
The present invention relates to process for producing dough pieces, and more particularly, high volume apparatus for producing dough pieces cut from extruded dough.
In the baking industry there are continuous technological efforts to increase the rate of product flow through the dough forming, baking, and packaging operations of the manufacturing process.
The dough pieces for certain baked products are formed by the wire cut method. In this operation, dough is extruded from a horizontally oriented die and sections of the dough are sliced off by a thin moving wire.
The speed of the baking and packaging operations have advanced to the point where the commercially available wire cut machines cannot supply dough pieces at a rate sufficient to match those operations. While the extrusion rate can be increased considerably without difficulty, there is a practical limit to the speed at which the cutting wire will efficiently form dough pieces.
A wire cut machine deposits pieces onto a conveyor belt in a series of parallel rows or columns. The normal speed of operation of these machines is between 150 and 180 pieces per minute for each line deposited on the conveyor.
At these speeds, the wire cuts cleanly through the extruding dough without transferring a significant amount of energy to the piece cut off. The pieces fall vertically onto the conveyor in a consistent uniform pattern. When these machines run at speeds greater than 180 pieces per minute, the pattern is disrupted in two ways. At these high speeds the machine begins to vibrate and this effects the placement of the dough pieces. Also, the wire, because of its speed, transfers sufficient energy into the pieces to throw the pieces horizontally in an unpredictable manner. In addition, when the dough contains particles such as chocolate chips, the energy transferred to the pieces varies according to the number and location of the particles which are struck by the wire as it passes through the extrusion.
As a result of this unpredictable horizontal displacement of the dough pieces, the dough pieces are deposited on the conveyor in an irregular pattern which effects the baking and packaging operations. Modern efficient automated packaging machinery requires that the baked articles be arranged in well defined rows. Also, wire cut dough pieces generally spread during baking. Therefore, dough pieces which are too close together fuse into one large irregular baked piece and must be discarded. Modern packaging methods also require that the dough pieces be uniform in size so as to produce baked products of uniform size and weight which can be processed by automatic machinery.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide apparatus for producing dough pieces in high volume.
Another object is to provide such apparatus for producing wire cut dough pieces arranged in well defined rows.
Another object is to provide extrusion apparatus containing simple and effective means for balancing the flow of dough from a plurality of nozzles fed by a common source.
The foregoing objects are accomplished by providing a conveyor and a dough piece former having plural outlets spaced along the direction of travel of the conveyor, the speed of the conveyor being related to the operating speed of the dough piece former so as to form a line of evenly spaced dough pieces; and by providing throttling apparatus for balancing the flow of dough from a common source to individual nozzles.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred embodiment of the invention have been chosen for purpose of illustration and description and is shown in the accompanying drawings, forming apart of the specification, wherein:
FIG. 1 is a side elevational view of a wire cut, dough piece forming apparatus according to the present invention,
FIG. 2 is a plan view taken generally along line 2--2 on FIG. 1,
FIG. 3 is an enlarged view of a portion of FIG. 2 showing flow adjusting mechanisms,
FIG. 4 is a sectional view taken along line 4--4 on FIG. 3,
FIG. 5 is an end view of the arrangement shown on FIG. 3,
FIG. 6 is a side view of a flow adjusting rod,
FIG. 7 is a front view of an auger positioning spacer, and
FIG. 8 is a plan view of a portion of the conveyor illustrating the drop sequence of dough pieces in forming a row of dough pieces.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawing in detail, there is shown apparatus according to the present invention which includes a conveyor 10 having a belt 11, are a wire cut dough machine 12 positioned over the conveyor. The machine 11 incorporates a series of dual extruders 14 spaced across the conveyor 10, each having two extrusion nozzles 15, 16. The extruders 14 are fed from a common hopper 17 by two feed rolls 18, 19. The hopper 17 and the rolls 18, 19 extend transversly of the conveyor across the extruders. A wire cut mechanism 20 simultaneously slices through the dough extruding from the nozzles 15, 16 to form dough pieces which fall upon the conveyor belt.
Referring now to FIG. 4, dough is forced by the rolls 18, 19 between a pair of scrapers 21 into the inlets 22 of the extruders. Each of the extruders 14 comprise a dual auger 24 fitted into a bore 25 in an auger housing 26. The nozzles 15, 16 are fastened to the bottom of the housing 26 inline with discharge openings 27, 28 at opposite ends of the dual auger.
The dual auger 24 comprises a right hand thread section 29 and a left hand thread section 30 which meet at the center beneath the inlet opening 22.
At the discharge ends of the augers, the minor diameter (the diameter of the central body) is increased to develop a greater dough pressure at the nozzles.
The shafts 32 on which the augers are formed are journalled at one end in a bearing block 34 and extend in the opposite direction through a block 35 which supports the drive motor 36 and gear train 37 which power the augers. The gear train includes a drive gear 39 mounted on the end of each shaft 32 and intermeshed with the adjacent gears 39. Since the gear train drives adjacent shafts in opposite directions, the augers formed on adjacent shafts are pitched oppositely. The shafts 32 are locked against axial movement with respect to the block 35 by suitable thrust bearings.
The support block 35 is mounted on a pair of shafts 40 which extend through the block 35 and into a bore 41 in the auger housing 26, as shown in FIG. 2. A rod 42, threaded at both ends, extends through the auger housing and is screwed into the end of the shaft 40 in the bore 41. A nut 44 is provided on the free end of the rod 42 to position the support block 35, and thereby the augers 24, relative to the auger housing 26. The position of the augers 24 with respect to the inlets 22 effects the relative rate of dough flow to the left hand and right hand portions of the auger.
The free end of each shaft 40 rests, for support, on the edge of a vertical plate 45, as shown in FIG. 1. A tube 46, provided with a slot in the bottom to admit the plate 45, surrounds the free end of each shaft 40. Each tube 46 is provided with a cap 47 on its free end and a flange 49 on the end adjacent the block 35. A bolt 50 extending through the cap 47 is threaded into the end of the shaft 40 to urge the sleeve to the right (as seen in FIG. 1) and position the flange 49 against the block 35.
Referring to FIG. 2, a space 51 is positioned between the block 35 and the auger housing 26. The spacers, shown in plan view in FIG. 7, are provided with counter-sunk bolt holes 52 and are bolted to the housing 26. The thickness of the spacer needed is determined by trial and error using thin shims where the spacer is. The machine 11 is placed in operation and the spacing between the block 35 and the housing 26 is adjusted by the adding and removing of shims until the flow rate from the nozzles 15 and the nozzles 16 are equal. Spacers of the required thickness are then substituted for the shims.
In a conventional bakery setup, the wire cut dough machine could contain 18 or more augers spaced across the conveyor belt. The augers and bores are formed by machining, and, even with strict tolerances some variations from part to part are unavoidable. Also, the flow rate from the hopper to the inlet openings tend to decrease at the ends of the hopper where friction with the end walls of the hopper produces a degree of laminar flow. The effects of these factors would result in variations in the size of the dough pieces in some rows with respect to that in others. Therefore, individually adjustable throttling mechanisms are provided at each inlet 22 to balance the output of the extruders 14.
As shown in FIGS. 3 and 4, a choke rod 54 extends through the auger housing 26 to intersect the edge of each opening 22. The rods 54 are cut out to provide a curved surface 55 which matches the contour of the edge of the inlet 22. When the surface 55 is vertically oriented, the inlet is unrestricted allowing full flow into the dual extruder. As the rod 54 is rotated through 90 degrees, the restriction provided by the rod increases to a maximum. Each rod 54 is rotationally positioned by means of an adjustment plate 56. A square formation 57 is provided on the free end of the rod. The plate 56 has a matching square hole (not shown). The plate is mounted on the formation 57 and held by a bolt 58.
Referring also to FIG. 5, the shape of the adjustment plate 56 approximates a circular quadrant. A curved slot 59 is formed in the plate along a 90 degree circular arc having its center at the axis of the rod 54. Each adjustment plate 56 is locked in position by a bolt 60 which extends through the curved slot, into the edge of a block 61 mounted on the auger housing 26.
The wire cut mechanism 20 includes a guide rod 62 mounted on each end of the machine 12 by a bracket 64. Sliding blocks 65 and 66 are mounted on each of the rods 62 on either side of the support bracket 64. Wire holding fingers 67, 68 are mounted on pivoted rods (not shown) which extend between the blocks 65, 66. Wires are stretched across the conveyor belt 11 between the free ends of the fingers 67 and between the free ends of the fingers 68. The sliding blocks 65 and 66 on each side of the machine are interconnected by bars 69 for snychronous motion. The sliding blocks are reciprocated upon the guide rods by a crank mechanism 70 driven by a motor 71. The reciprocating motion of the blocks 65, 66 more the cutting wires past the nozzles. Another crank mechanism (not shown) also driven by the motor 71 pivots the wire holding fingers 67, 68 upwardly toward the nozzles at the beginning of the cut stroke so that the wires move across the faces of the nozzles as the extrusion is sliced. On the retract stoke, the wire holding fingers are pivoted downwardly so that the wires pass below the end of the extruding dough streams.
The conveyor 10 is driven by a motor 72 provided with a speed control unit 74. The speed of the conveyor is adjusted with relation to the speed of operation of the cut-off mechanism 20, so that, between dough piece drops, the conveyor belt 11 moves a distance equal to two thirds of the spacing of the nozzles 15 and 16. Referring to FIG. 8, there is shown the drop pattern for one set of nozzles 15, 16. The nozzles are positioned above the circles marked "Drop Point" and are separated by a distance X as indicated. The circles on the conveyor belt 11 represent the dough pieces formed on four consecutive drops. The position of these dough pieces is that which they occupy at the time the fourth drop is made. The dough pieces marked "1" were dropped on the first drop and have moved through a distance of three times 2/3X. The dough pieces marked "2" were dropped on the second drop and have moved through a distance of two times 2/3X. The dough pieces marked "3" were dropped on third drop and have moved the distance 2/3X.
Of these pieces, the "A" pieces were dropped from a nozzle 15 and the "B" pieces were dropped from a nozzle 16. The "A" pieces are separated from each other by a distance of 2/3X. The "B" pieces are likewise separated from each other by a distance of 2/3X, and each "B" piece falls halfway between two consecutive "A" pieces. Thus a line of dough pieces are formed in which the consecutive pieces are separated by one third the distance between the nozzles.
It will be seen from the foregoing that the present invention provides apparatus for producing dough pieces in high volume which are arranged in well defined rows and are of uniform size and weight.
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Dough pieces are produced in high volume by a plurality of dual extruders spaced across a conveyor and each having a pair of extrusion nozzles aligned in the direction of conveyor travel. A cut-off mechanism severs the dough extrusions to deposit dough pieces on the conveyor. The speed of the conveyor is related to the speed of the cut-off mechanism so that the dough pieces produced by each extruder form a single uniformly spaced line. The extruders are fed from a common supply through individual inlets and means are provided to balance the flow through the nozzles.
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The subject matter of the present invention relates to perforating operations. More specifically, the present invention relates to a conveyed wellbore intervention tool for perforations.
BACKGROUND OF THE INVENTION
After drilling a wellbore into a hydrocarbon-bearing formation, the well is completed in preparation for production. To complete a well, a casing (liner), generally steel, is inserted into the wellbore. Once the casing is inserted into the wellbore, it is then cemented in place, by pumping cement into the gap between the casing and the borehole (annulus). The reasons for doing this are many, but essentially, the casing helps ensure the integrity of the wellbore, i.e., so that it does not collapse. Another reason for the wellbore casing is to isolate different geologic zones, e.g., an oil-bearing zone from an undesirable water-bearing zone. By placing casing in the wellbore and cementing the casing to the wellbore, then selectively placing holes in the casing, one can effectively isolate certain portions of the subsurface, for instance to avoid the co-production of water along with oil.
The process of selectively placing holes in the casing and cement so that oil and gas can flow from the formation into the wellbore and eventually to the surface is generally known as “perforating.” One common way to do this is to lower a perforating gun into the wellbore using a wireline or slickline cable to the desired depth, then detonate a shaped charge mounted on the main body of the gun. The shaped charge creates a hole in the adjacent wellbore casing and the formation behind the casing. This hole is known as a “perforation”. U.S. Pat. No. 5,816,343, assigned to Schlumberger Technology Corporation, incorporated by reference in its entirety, discusses prior art perforating systems.
In order to optimize the performance of perforated completions, it is necessary to know the details of the completion behaviour. For example, it is beneficial to know which perforations are flowing and which are not due to conditions such as formation debris blockage or tunnel collapse. Additionally, it is beneficial to know what fluids are flowing from the individual perforations and which tunnels are producing sand as well as hydrocarbons. If the behavioural details of the individual perforations are known, then treatments for detrimental conditions can be appropriately applied.
Related oilfield technology exists in a number of areas. For example, for open hole sections of the well, images are frequently acquired using tools such as the Ultrasonic Borehole Imager (i.e., acoustic pulses), the Formation Microscanner (i.e., electrical resistivity) or the GeoVision resistivity tool. However, these devices are not applicable to cased hole environments.
In cased holes, Kinley calipers or similar tools are used to form maps of damage or holes in casing by using mechanical feelers as the sensing elements. Downhole video cameras can also be used to view perforations in cased holes, but the well must be shut-in (or very nearly shut-in) and filled with filtered fluid for the cameras to be effective. Temperature logs and production logging tools can be used in cased holes but have no azimuthal sensitivity and insufficient depth resolution to detect problems with individual perforations.
A technology has been proposed the international Patent application PCT/GB2005/004416 filed on 16 Nov. 2005 to use a wireline tool with pads containing arrays of flow, sand and fluid type sensors, to map the inflow in a perforated completion. In principle the apparatus and methods described in the application enable the detection of individual non-flowing, sand-producing or watered-out perforation holes. The location of these non-performing perforations can thus be established with some precision, at least relative to the tool body.
In case perforated completions suffer from limited productivity or other faults, various methods have been proposed and are used in remedial operations. These remedial methods include bullheading acid, re-perforation, pressure jetting and ultrasound excitation. All these remedial methods, for sand, water and poor productivity, are not selective and address an entire completed interval at least.
There exists, therefore, a need to optimize remedial operations on existing but non-performing perforations in perforated sections of a wellbore.
SUMMARY OF THE INVENTION
According to an aspect of the invention, there is provide a apparatus which is adapted to be conveyed into a wellbore by a wireline, drill string, coiled tubing or other suitable conveyance methods, which apparatus being capable of
detecting a perforation; establishing whether or not the perforation is performing according to a preset condition or parameter; and launching an intervention tool adapted to perform a local remedial operation on a non-performing perforation only or at the most on the non-performing perforation and its closest neighbors.
The detection and performance check on perforation are preferably performed using a visual or optical inspection or a perforation specific flow detection tool such as described for example in the aforementioned international Patent application PCT/GB2005/004416 fully incorporated herein by reference.
The intervention tool is preferably based on apparatus and methods described for the purpose of drilling perforations into cased wellbores in the U.S. Pat. No. 5,692,565 fully incorporated herein by reference. It was found that the apparatus described therein can be adapted to provide a tool for individually engaging a non-performing perforation.
Among the preferred remedial operations are ultrasonic or jet cleaning, injection of chemicals such as swelling polymers, gels, or acids, filter placements using for example wire, polymer or carbon filters, sealing operations based either on chemical injection as above or the installation of mechanical seals or valves or packers.
A preferred tool in accordance with the invention includes a depth control to position the intervention tool at the depth of a previously identified non-performing perforation.
A preferred tool in accordance with the invention includes an azimuthal control to position the intervention tool at the approximate or exact azimuthal angle of a previously identified non-performing perforation.
An even more preferred tool in accordance with the present invention includes a depth and azimuthal control to position the intervention tool in juxtaposition to the opening of a previously identified non-performing perforation
These and other aspects of the invention will be apparent from the following detailed description of non-limitative examples and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A illustrates an embodiment of the present invention;
FIG. 1B illustrates a detail of FIG. 1A ; and
FIG. 2 illustrates a further variant of the present invention.
DETAILED DESCRIPTION
A first embodiment of the present invention is illustrated in FIG. 1A . In this embodiment, one or more sensors 16 are placed on an equivalent number (only two shown) of arms 18 that extend in operation from the main body 11 of the tool. The main body 11 is moved in the wellbore on a conveyance tool 111 , which can be a wireline, coiled tubing, a drillstring or any other suitable conveyance apparatus. In this configuration, the extending arms 18 enable the sensors 16 to fold up easily to facilitate passage through the casing 12 and to be brought into close proximity to the opening 13 of perforations. The sensors 16 are shown oriented such that their sensitive face is oriented towards the flow from the perforations and less exposed to the main flow. Arrows indicate the respective flow directions.
In a variant not shown for the sake of clarity, the sensors 16 are placed in a protective cage such that the arms 18 can be extended in operation against the inner wall of the casing 12 without causing damage to the sensors.
In a lower part of the tool body there are shown two perforation intervention tools 151 , 152 representative of a group of intervention tools which may include ultrasonic or jet cleaning tools, chemical injection tools, or carriers or placements tool for filters, mechanical seals, valves or small packers to close or constrict the perforations.
The tools 151 , 152 are mounted on telescopic arms 153 which extend from the tool body 11 to the opening 13 of a perforation and, if required, into the perforation.
There are also shown pads 17 which can in operation been extended against the casing to provide a counterforce and/or anchor the tool body in the wellbore.
The extendable devices arms 153 , 17 , 18 are hydraulically operated or use electric actuators for extending, positioning and retraction into the tool body.
The tool includes electronic devices 19 to control the downhole operation of the tool and to communicate measurements to the surface and to receive instructions from a surface operator.
A more detailed view of a perforation intervention tool for sand control purposes is shown in FIG. 1B retaining the numerals used in FIG. 1A for identical or similar elements. The intervention tool inserts a tube 151 (shown cutaway) into the perforation tunnel 13 , and a coaxial piston 154 then pushes a sand control plug 155 into the tunnel as the tube withdraws. The plug is made of an elastic mesh that springs open as it is released from the tube, together with an elastic fishbone structure that provides some support to the mesh and also locks it within the tunnel.
In FIG. 2 , the tool of FIG. 1 is shown, again retaining the numerals used in FIG. 1A for identical or similar elements, enhanced by an azimuthal orientation tool 14 comprising an gyroscopic instrumentation and control section 141 , an anchor 142 shown as a bow spring to anchor the top of the tool to the casing and a motor 143 to rotate the intervention tool into a desired azimuthal orientation. Such an orientation section is described for general downhole applications for example in the U.S. Pat. No. 6,173,773, fully incorporated herein by reference.
In operation, the tool is first lowered into a wellbore and then pulled slowly back to the surface with its arms 18 extended and sensors 16 placed close to or touching casing wall.
Once a problem perforation has been located, mechanical tools below the detection pads can be deployed to fix it. Using the known depth difference between detector pads 16 and the intervention tool 151 , 152 , the tool is stopped in the appropriate position, and be anchored there; the anchoring does not need to be powerful, and the anticipated treatments would not take much time per hole. Possible mechanical fixes then applied include:
For a perforation hole that is not flowing, or flowing much less than its neighbors—anchor the tool and insert a stimulation device through the perforation hole into the tunnel or whatever is obstructing it. This device could be an ultrasonic source, a mechanical drill or agitator, a pellet of propellant with an ignitor, a high-pressure jet of wellbore fluid, or some other source of mechanical energy. The aim is to disrupt fines accumulations around the perforation tunnel, or shake free whatever is blocking the hole. For a tunnel that is flowing too much water—anchor the tool and either a) insert a tube into the hole and tunnel which deposits a swelling gel pellet to fill the tunnel and prevent flow, or b) block the casing hole itself with a metal-to-metal sealing plug of the type used in the CHDT. A perfect seal is not needed. For a tunnel that is flowing sand—anchor the tool and either a) block the hole as for water shutoff, or b) insert a tube into the tunnel and deposit a mesh filter plug in the tunnel, which allows fluid to flow but blocks sand particle movement, or c) insert a tube and deposit a miniature gravel pack within the perforation, using resin-coated gravel which is then cured by an UV source or the subsequent injection of a chemical activator.
There are other intervention possibilities.
In the case of sand control the insertion of a filter plug would be a permanent solution, until reservoir or drawdown conditions change so that other perforations start to fail, or until the filter plug is damaged or dissolved by the production flow. As such it could potentially be a method for primary sand control, during the initial completion of the well. It leaves the wellbore entirely free of obstruction, and is repairable as required using a similar tool.
While the invention has been described in conjunction with the exemplary embodiments described above, many equivalent modifications and variations will be apparent to those skilled in the art when given this disclosure. Accordingly, the exemplary embodiments of the invention set forth above are considered to be illustrative and not limiting. Various changes to the described embodiments may be made without departing from the spirit and scope of the invention.
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The present invention provides a conveyance tool and a tool string having one or more sensors or cameras for detecting the performance of pre-existing perforations in a cased wellbore, and one or more perforation intervention tools mounted on the tool string and capable of performing remedial actions directed at most one perforation and its nearest neighbors or at a single perforation.
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BACKGROUND OF THE INVENTION
The invention relates to an electronic sewing machine which is controlled with electric signals to produce stitches, and is provided with a device for electrically diagnosing malfunctions of the electric components and the parts related thereto.
Because of the wide distribution of electronic sewing machines, integrated circuits have been used in the household sewing machine. However, the maintenance of the sewing machine has often required a skilled electric knowledge and a particular separate trouble diagnosing device. Therefore the sewing machine makers have not been able to supply good service to the sewing machine users after the makers have sold the sewing machine.
SUMMARY OF THE INVENTION
The invention has been provided to eliminate the defects and disadvantages of the prior art. It is therefore a primary object of the present invention to supply the electric control part of the sewing machine with the functions of both stitch control and trouble diagnosing control, which may be selectively effectuated by operation of a changeover switch.
It is another object of the present invention to utilize the pattern selecting switches and the indicating illumination lamps for designation of stitch patterns and indication thereof and for designation of malfunction diagnosing processes and indication of diagnosed results.
According to the present invention, the sewing machine is incorporated with a microcomputer which has a stitch control operation program and a malfunction diagnosing operation program. These two programs may be selectively effectuated by a changeover switch. With the operation of the changeover switch, the pattern selecting switches and the related indicating illumination lamps are used for actual pattern selection as the specific function thereof in accordance with the stitch control operation program or for designating the malfunction diagnosing processes and indicating the results in accordance with the malfunction diagnosing operation program.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of a sewing machine of the present invention;
FIG. 2 is a view of the operating panel of the sewing machine shown in FIG. 1;
FIG. 3 is a bottom view of the sewing machine of FIG. 1;
FIG. 4 is a view showing a trouble diagnosing attachment form to be placed on the operating panel of the sewing machine shown in FIG. 1;
FIG. 5 is a control circuit block diagram showing an embodiment of the present invention;
FIGS. 6A to 6E are flow charts of control for the sewing machine shown in FIG. 1; and
FIG. 7 is a table showing the diagnosis instructions for the sewing machine shown in FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows the outer appearance of the sewing machine. On a panel 2 at a front part of the sewing machine 1, there are disposed, as shown in FIG. 2, a switch operating part 3, an indicating part 4, a stitching width adjusting dial 5 and a feed adjusting dial 6. On a bottom side 7 of the sewing machine 1, there are, as shown in FIG. 3, a switch (SWc), pilot lamps (PL 1 ), (PL 2 ), (PL 3 ) and (PL 4 ) which are normally untouchable in the ordinary use of the sewing machine. The switch (SWc) switches the control circuit of the sewing machine between an ordinary sewing function and a malfunction diagnosing function. The pilot lamp PL 1 is an indicator for the driving power source of the stitch control motors. The pilot lamp (PL 2 ) is an indicator for the power source of the control circuit. The pilot lamp (PL 3 ) is an indicator for the drive control signal of the machine motor. The pilot lamp (PL 4 ) is an indicator for the control signal of the machine motor braking.
The switch operating part 3 comprises a set of pattern selection switches (S 1 ) to (S 8 ), a switch (S 9 ) for finish-up stitching, a low speed designating switch (S 10 ), a stitching width control dial 5 and a feed control dial 6.
The indicating part 4 comprises illumination lamps (L 1 ) to (L 28 ). The lamps disposed in a row, for example, (L 1 ), (L 2 ), (L 3 ), switchingly light in succession for each operation of the switch (S 1 ) when a pattern corresponding to the lighting lamps is selected. The patterns corresponding to the lamps (L 1 ) to (L 24 ) are selected in response to the operation of the switches (S 1 ) to (S 8 ). The switch (S 9 ) of the finish-up stitching and the switch (S 10 ) of the low speed, correspond to the lamps (L 25 ) and (L 26 ), respectively.
Each time the dials 5 and 6 are pushed they become effectuated to adjust the lateral swinging movement of the needle and the fabric feed respectively by rotating the same dials, and each becomes effectuated to set the sewing machine to an automatic stitching mode irrespective of the rotation of the dials. When the dials are switched to the manual rotation adjustment, the lamps (L 27 ) (L 28 ) light, and then the adjustment value is designated by the rotation of the dials.
FIG. 4 shows the malfunction diagnosing attachment form 8 attached on the operating panel 2. It is made of a thick paper which is formed with holes in correspondence to the position of the switches (S 1 ) (S 2 ), the lamps (L 1 ) (L 3 ) etc. Although not shown, the thick paper is printed with letters or marks for indicating the switches and lamps, and for instructing the diagnosing processes.
FIG. 5 is a control circuit diagram in which a print board (A) is attached to the inner side of the operating panel 2 of FIG. 1. A key board (KEY) including a key matrix (not shown) is scanned by a signal from a print board (B) when the switches (S 1 -S 10 ) and the dials 5, 6 are operated, and the resultant designated information is given to the print board (B). The light indicating board (LED) selectively lights the lamps (L 1 ) to (L 28 ) of the indicating part 4 in accordance with the signals from the print board (B). A stitching width adjusting device (AJ B ) and a feed adjusting device (AJ F ) give the print board (B) switch operating information when the dials 5 and 6 are pushed and adjusting position information when they are rotated. The print board (B) substantially constitutes a microcomputer (MC), and is attached to the inner side of the bottom 7 of the machine body 1. The parts of the print board (A) are each connected to the microcomputer by a connector (CN 1 ).
The microcomputer (MC) prepares a stitch control operation program which is an inherent function of the electronic sewing machine, and also prepares a malfunction diagnosing control operation program which diagnoses malfunctions in the electric components of the sewing machine and mechanical components related to the electric components. The two different programs are selectively effectuated by the operation switch (SWc). A needle swing control motor driving circuit (DV B ) is provided on the print board (B) and receives a control signal from the microcomputer (MC) and controllably drives a needle swing control motor (SWM B ) (a pulse motor, in the present embodiment). A position signal from a position sensor (S B ) (for setting an initial position of the pulse motor, in the present embodiment), which is mechanically connected to the motor, is furnished to the microcomputer (MC). A feed control motor driving circuit (DV F ) is attached to the print board (B) and receives control signals from the microcomputer (MC) and controllably drives the feed control motor (pulse motor) (SVM F ), and in the same way, the position signal of the position sensor (SF) (For setting the initial position of the pulse motor) is funished to the microcomputer (MC). Control motor units (U B ) (U F ) each comprise a couple, formed from the control motor and the position sensor, and are connected to the corresponding drive circuits of the print board (B) through a connector (CN 2 ).
Print board (C) substantially constitutes a machine motor driving circuit (DV SE ) which receives, via a connector (NC 3 ), a machine motor speed control signal and a braking control signal for stopping the needle at a determined position, and furnishes a driving control signal to the machine motor (SEM) through a connector (CN 4 ). An upper shaft sensor (SEN) is mounted on an upper shaft (not shown) to be driven by the machine motor (SEM), and furnishes, via a connector (CN 5 ) to the microcomputer (MC), a needle swing control phase signal, a feed control phase signal and a rotation speed signal of the upper shaft. An external wire connector (CN 0 ) receives a commercial power source (V 0 ). The connector (CN 0 ) has a power source switch (SW 0 ) and furnishes the power source (V 0 ) to the machine motor driving circuit (DV SE ) via a connector (CN 6 ) and a power source fuse (F 0 ). The external wire connector (CN 0 ) is connected to pedal controller (CONT) for controlling the speed of the machine motor and furnishes an electric signal effectuated by the operation of the controller to the microcomputer (MC) of the print board (B).
A primary side of a power source transformer (Tr) is connected to the print board (C) via a connector (CN 8 ) and receives the power source (V 0 ) via the fuse (F 0 ). A secondary side thereof is connected to the print board (B) via the connector (CN 9 ) and supplies the power source to a control motor driving power source circuit (Vsv) via a fuse (F 1 ) and also supplies the electric current to a control power source (Vcc) of a control circuit device. Output (X) of the control motor driving power source circuit (Vsv) is supplied to the needle swing control motor driving circuit (DV B ) and to the feed control motor driving circuit (DE F ). Output (Y) of the power source circuit (Vcc) is supplied to each of the circuits of the print boards (A) (C). The print board (B) is provided with the pilot lamps (PL 1 ) (PL 2 ) of the outputs (X) (Y) and pilot lamps (PL 2 ) (PL 3 ) of the machine motor speed control signal and the brake control signal to be supplied to the machine motor driving circuit (DV.sub. SE).
Explanation as to the stitch control operation of the control circuit in FIG. 5 is dispensed with because the operation is described in the copending Japanese patent application 53-145280 by the same applicant. A further explanation will be made to the malfunction diagnosing operation of the invention with reference to the flow charts. If the power switch (SW 0 ) is turned on when the switch (SWc) is positioned at the normal sewing function designating side, then the stitch control operation program is started by the microcomputer (MC). If the switch (SWc) is positioned at the malfunction diagnosis function designating side, then the malfunction diagnosis control operation is started. The process No. 1 is to light and check the indicating part 4. The lamps (L 1 ) to (L 28 ) are divided into groups comprising three lamps per line. The lamps (a first group is L 1 , L 2 , L 3 ) in each of the groups are lighted (ON) and the groups are either switched ON sequentially or the lamps are switched ON one by one at a predetermined time interval by a timer. The process No. 1 is repeated if all of the lamps do not light ON. If all of the lamps are not lit, the diagnosing operator checks and takes the required action in accordance to the instructions of the table shown in FIG. 7 which may be printed on the attachment form 8. If none of the lamps (L 1 ) to (L 28 ) are lit, the pilot lamps (PL 1 ) (PL 2 ) on the bottom side 7 of the sewing machine 1 are checked. If the two pilot lamps are not lit (OFF), the fuse (F 0 ) is checked and if necessary replaced, the transformer (Tr) is replaced and the print boards (B) (A) are replaced in accordance with the predetermined order, from the numbers 1 to 4 of the instructions of the table shown in FIG. 7, while the condition of the lamps (L 1 ) to (L 28 ) is observed each time the instructions 1 to 4 are fulfilled.
If the pilot lamp (PL 1 ) is ON and the pilot lamp (PL 2 ) is OFF, then it is required to check and if necessary replace the fuse (F 2 ) and the print boards (B) (A) in the order of the numbers 1, 2, 3. If the pilot lamp (PL 2 ) is ON, the print board (B) and (A) are replaced in the order of the numbers 1, 2 irrespective of the ON or OFF of the pilot lamp (PL 1 ). If some of the lamps (L 1 ) to (L 28 ) are not ON, then the print boards (A) and (B) are replaced in accordance with the order of the numbers 1, 2. When all of the lamps (L 1 ) to (L 28 ) are lit (ON), the program advances to the process No. 2, on the assumption that there is no malfunction in the process No. 1. This is to check the switching function by the switch operating part 3, and a checking switch is set first. Firstly, the switch (S 1 ) is set and the lamp (L 1 ) is set and is alternately turned ON and OFF to indicate the checking designation of the switch (S 1 ). When the switch (S 1 ) is pushed, the ON-and-OFF operation of lamp (L 1 ) is changed to continuous lighting, and then the diagnosing operator knows that the switch (S 1 ) is functioning. When the switch (S 1 ) is released, the checking switch (S 2 ) is set, and the lamp (L 4 ) is alternately turned ON and OFF to indicate the checking designation of the switch (S 2 ). In the same way, the subsequent switches (S 3 -S 10 ) and the switching functions of the dials 5, 6 are checked and confirmed. Thus, the process No. 2 is completed and the program advances to the sequence No. 3. In the process No. 2, if the operation of any switch does not change the ON-and-OFF of the lamps to the ON condition, then something is malfuncting with the switch and the print board (A) is replaced. If then the switch is still malfunctioning, then the print board (B) is replaced.
The process No. 3 confirms the electric functions of the sewing machine under the condition that the process No. 1 and No. 2 show that the switching functions and the lamp indication functions are functioning properly. In this case lamp (L 1 ) is first alternately turned ON and OFF to inform the operator that this is the diagnosis of the process No. 3. The operator attaches the attachment form 8 shown in FIG. 4 to the operating panel 2 of the sewing machine 1. The attachment form 8 is a guide for advancing the program, in a dialogue system, through operations of the switches (S 1 ) (S 2 ) and the lamps (L 1 ) (L 3 ) on the operating panel 2, and although not shown, guide words are printed at positions corresponding to the lamps and the switches. For example, the word "prepared" is printed in correspondence to the lamp (L 1 ), and "YES" is printed for the switch (S 1 ) for confirming the preparation or the normal operation.
When the switch (S 1 ) is operated, the program advances to the next function confirmation. That is, to junction (1) in FIGS. 6A and 6B. Then the needle swing control motor (pulse motor) (SVM 8 ) is driven, and the position sensor (S B ) reverts to the predetermined initial position where the sensor receives a detecting signal to indicate that the motor has been set to the initial position. Furthermore, the motor (SVM B ) is operated and the needle is brought to the leftmost position of the maximum amplitude, and the lamp (L 4 ) is alternately turned ON and OFF. At this position, the words "Needle left" are printed and the operator knows that the needle is at the left position. When the needle is positioned at the left and the switch (S 1 ) is operated to confirm that the electric control is functioning properly, the motor (SVM B ) is operated and brings the needle to the center of the maximum needle amplitude, and then the lamp (L 5 ) is alternately turned ON and OFF. When the switch (S 1 ) is operated, the needle is brought to the rightmost of the maximum amplitude, and then the lamp (L 6 ) is alternately turned ON and OFF, and the program advances to junction (2) of the flow chart in FIGS. 6B and 6C by the operation of the switch (S 1 ). If the indications of the lamps (L 4 ) (L 5 ) (L 6 ) are not in the normal relation with the corresponding positions of the needle, then the operator operates the switch (S 2 ) on which the word "NO" is printed. Then, it is indicated that the needle swing mechanism in connection with the needle swing control motor (SVM B ) is not correctly adjusted, and the program advances to junction (2).
If the motor does not finish the initial setting, the program advances to junction 2. The feed control motor (pulse motor) (SVM F ) is operated, and the position sensor (S F ) is brought to the initial position, and the initial setting is indicated. If the needle swing control motor (SVM B ) does not complete the initial setting, it is indicated that the print board (B) is malfunctioning and the needle amplitude control motor (SVM B ) is malfunctioning. Then the feed control motor (SVM F ) is operated and the maximum reverse feed is set, and the lamp (L 7 ) is alternately turned ON and OFF, which is printed with the mark "-2.5 mm" indicating the maximum reverse feed. If the needle swing control motor (SVM B ) completes the initial setting, the feed is set and the lamp is alternately turned on and off without the "malfunction" indications.
The operator manually and slowly drives the sewing machine and checks that the fabric is fed backwardly by 2.5 mm, and operates the switch (S 1 ). With operation of the switch (S 1 ), the feed is set at 0 and the corresponding lamp (L 18 ) is alternately turned on and off. The operator manually drives the sewing machine to check it and then operates the switch (S 1 ). With the operation of the switch (S 1 ), the normal feed of 5 mm is set and the corresponding lamp (L 9 ) is alternately turned on and off, and the operator drives the sewing machine to check this and the program advances to the junction (3). If the feeds corresponding to the lamps (L 7 ) (L 8 ) (L 9 ) are not proper, the information is indicated by the operator's operation of the switch (S 2 ), and the program advances to the junction (3). If the feed control motor does not finish the initial setting and if the initial setting of the needle swing control motor (SVM B ) has been finished, it is then indicated that the print board (B) and the feed control motor are malfunctioning, and the program advances to the junction (3). If the needle swing motor (SVM B ) has not finished the initial setting, it is indicated that the print board (B) is malfunctioning, and the program advances to the junction (3). Then the lamp (L 10 ) is alternately turned on and off, where the words "Press machine controller" are printed, and the operator knows that he should press the controller (CONT).
By operation of the controller (CONT), the controller becomes conductive. It is normal that the sewing machine is non-moving irrespective of the condition of the controller, pressed or not. The lamp (L 11 ) is then turned on where the word "rotation" is printed, and the sewing machine is set at the low speed rotation (120 rpm). When the controller is inconductive or not normal in the speed control or has been made conductive, it is indicated by operating the switch (S 2 ) that the controller is malfunctioning and the lamp (L 11 ) is turned on and the sewing machine is rotated at a low speed. When the sensor (SEN) of an upper shaft is normally operated, to detect the rotation speed (120 rpm), the needle swing control phase (called "upper position") and the feed control phase (called "lower position"), the program then advances to the juncture (4), since the detecting controls of the upper shaft sensor (SEN) are functioning properly.
When the upper shaft sensor (SEN) does not detect any of these, the program advances to the junction (5), and the lamp (L 11 ) is alternately turned on and off, and the operator knows that he should check if the sewing machine is operating. If the sewing machine is not operating, and the switch (S 2 ) is operated, and the lamp (L 11 ) is alternately turned on and off where the words "PL 3 lighting" are printed, then the operator knows that he should check if the pilot lamp (PL 3 ) on the bottom side 7 of the sewing machine 1 is lit. If the lamp is not lit and if then the switch (S 2 ) is operated it is indicated that the print board (B) is malfunctioning, then the program advances to the junction (8). If the pilot lamp (PL 3 ) is not lit, and if then the switch (S 1 ) is operated, it is indicated that the print board (C) is malfunctioning, and then the program advances to the junction (8).
If the detecting controls of the upper shaft sensor (SEN) are partly malfunctioning or if the operator confirms the rotation of the sewing machine after the junction (5) and then operates the switch (S 1 ), and it is indicated that the upper shaft senser (SEN) is malfunctioning via the junction (6), then the program advances to the junction (8). When the lamp (L 11 ) does not light, the upper shaft snsor (SEN) produces a rotation signal of the sewing machine in the discrimination of stopping of the sewing machine. The lamp (L 11 ) is then alternately turned on and off and operator checks the rotation of the sewing machine. If the sewing machine is not operating, the switch (S 2 ) is operated to indicate that the print board (B) is malfunctioning, and the program advances to the junction (8). If the sewing machine is operative and, the switch (S 1 ) is operated, then the program advances to the juncture (7) and the lamp (L 13 ) is alternately turned on and off. The operator checks if the pilot lamp (PL 13 ) is lit. If the lamp is lit and then the switch (S.sub. 1) is operated, this indicates that the print board (B) is malfunctioning. If the lamp is not lit and the switch (S 2 ) is then operated, it is indicated that the print board (C) is malfunctioning and then the program advances to the juncture (8).
If the program advances to the juncture (4), the sewing machine is set at a high speed rotation (1000 rpm).
If the rotation speed is above 800 (rpm), the sewing machine is set at the upper dead point of the needle stopping, and the machine motor (SEM) is then stopped and the lamp (L 12 ) is lit, where the words "Upper stopping" are printed, then the operator knows that the sewing machine is set at the upper dead point of the needle stopping. If the sewing machine is stopped within a determined range, the program advances to the juncture (8). If the sewing machine is stopped outside of this range, the lamp (L 14 ) is alternately turned on and off, where the words "PL 4 lighting" are printed, then the operator knows that he should check if the pilot lamp (PL 4 ) is lit on the bottom side of the sewing machine 1. If the lamp lights and then the switch (S 1 ) is operated, it is indicated that the print board (C) is malfunctioning and the program then advances to the juncture (8). When the lamp does not light, and then the switch (S 2 ) is operated, it is indicated that the print board (B) is malfunctioning and the program advances to the juncture (8) and the lamp (L 16 ) is then alternately turned on and off, where the words "Width dial 0" are printed then the operator knows that he should rotate the stitch width adjusting dial 5 to a scale "0".
When the stitch width adjusting dial is rotated to the scale "O" and then the switch (S 1 ) is operated, it is indicated on the condition that the stitch width adjusting signal is not minimal, that the width adjustment is wrong. If it is minimal, then the lamp (L 17 ) is alternately turned on and off without this indication, where the words "Width dial 7" are printed, then the operator knows that he should rotate the dial 5 to the scale "7". If the dial is rotated to the scale "7" and the switch (S 1 ) is operated, the same indication is made in dependence upon whether or not the stitch width adjusting signal is maximum, or the lamp (L 19 ) is alternately turned on and off without the indicating, where the words "Feed dial 0" are printed, then the operator knows that he should rotate the feed adjusting dial 6 to the scale "0". If the dial 6 is rotated to the scale "0" and the switch (S 1 ) is operated, then it is indicated that the feed control is malfunctioning on the condition that the feed adjusting signal is not minimal. If the feed adjusting signal is minimal, the lamp (L 20 ) is alternately turned on off without this indication, where the words "Feed dial 5" are printed, then the operator knows that he should rotate the dial 6 to the scale "5".
When the dial 6 is rotated to the scale 5 and then the switch (S 1 ) is operated, the indication is made in dependence upon whether or not the feed control signal is maximal, or the program advances to a next one without this indication. If all are indicated that the controller (CONT) is malfunctioning, the stitch width adjustment by the dial 5 is wrong and the feed adjustment by the dial 6 is wrong, it is indicated that the print board (B) is malfunctioning and the program then advances to the junction (9). If none of the above items is indicated, then the program advances to the junction (9) without indication that the print board (B) is malfunctioning. If any one of the stitch width adjustment value and the feed adjustment value is wrong, it is indicated that the print board (A) is malfunctioning, and the program then advances to the junction (9).
All the judgements of the diagnosed items are finished at the juncture (9), and the judged results are indicated. If there are no indications of malfunctioning items the lamp (L 3 ) lights to indicate that all is "Normal" and the program finishes. If the mechanism is malfunctioning, the lamp (L 15 ) is lit where the words "Control of mechanism" are printed. When the print board (A) is malfunctioning, the lamp (L 18 ) is lit where the words "Exchange of A board" are printed. When the print board (B) is malfunctioning, the lamp (L 21 ) is lit where the words "Exchange of B board" are printed. When the upper shaft sensor (SEN) is malfunctioning, the lamp (L 22 ) is lit where the word "SEN" is printed. When the controller (CONT) is malfunctioning, the lamp (L 23 ) is lit where the word "CONT" is printed. When the print board (C) is malfunctioning, the lamp (L 24 ) is lit where the word "C board" is printed. When the needle swing control motor (SVW B ) is malfunctioning, the lamp (L 25 ) is lit where the words "Needle swing control motor" are printed. When feed control motor (SVM F ) is malfunctioning, the lamp (L 26 ) is lit where the words "Feed control motor" are printed. The lamps are lit individually or simultaneously to indicate the malfunctioning parts, and the program is finished.
As having mentioned above, the malfunction diagnosing function is provided in the microcomputer for controlling the various stitching operations of the sewing machine. The diagnosing function is selectively effectuated together with the switches and indicating lamps which are specific to the conventional sewing machine. Therefore the structure for the diagnosing function is extremely simple, and accordingly the sewing machine may be easily diagnosed without professional knowledge and without any special diagnosing instruments.
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A stitch pattern sewing machine utilizes a microcomputer which operates in a stitch control mode and in a malfunction diagnosing mode. Each mode is selectively rendered effective by a changeover switch. The diagnosis of malfunction includes a series of checking steps carried out in a predetermined order. Indication means are selectively illuminated to operate in either one of the two modes in dependence upon the position of the changeover switch.
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BACKGROUND OF THE INVENTION
This invention relates to improvements in large scale underwater risers, and particularly is such as to provide a buoyancy system for large scale underwater risers which may be effective in deep waters, e.g., ocean waters of a depth of 3,000 meters or more.
Deep underwater drilling has become a requirement in order to tap sources of hydrocarbons from sites well below 1,000 meters or more underwater. In such drilling, a long drilling riser conduit extends between the site at the ocean floor to the vessel or floating platform. Such riser normally comprises a string of units (known as joints), the individual units being connected by means of flanges with one another.
One of the problems engendered in deep sea drilling using riser conduits is the problem of locating and maintenance of the riser with respect to the platform or vessel, particularly where the surface vessel or platform may be subjected to considerable movement both horizontally and vertically due to current, wave and wind action. Such problems, of course, may subject the risers to excessive axial and buckling stresses.
Generally speaking, a principal requirement for stability of the riser--i.e., immunity to buckling or other stress failures, etc.,--is that the riser must be maintained effectively in tension over its entire length. More specifically, the effective tension in a riser must be considered to be the pipe wall tension diminished by the effects of pressure differential across the pipe wall, seawater pressure gradient, and so on.
Another problem which is encountered at sea, particularly in deep water conditions, is that occasionally the buoyancy of a riser system may be required to be adjusted, sometimes very rapidly.
Thus, while in the past the riser string has been kept under tension by such means as pulling on the upper end of the riser, either using counterweights or automatic tensioning equipment located on the vessel, the continuing search for hydrocarbons in deeper ocean environments has made these proposals, on their own, incapable of handling greater depths.
Of late, accordingly, it has been proposed to provide buoyancy devices for risers which would be capable of attaining the required buoyancy capabilities at greater depths, so as to properly maintain the risers. One such means has been the use of syntactic foam; and floatation air cans have also been proposed as buoyancy devices for deep sea risers.
A well known detriment of syntactic foam, however, is that it loses its buoyancy capacity due to absorption of water or compaction of the syntactic material, especially at increased depths. Thus, acceptance testing--i.e., testing prior to actual use--is normally a requirement for these foams, primarily to determine the buoyancy loss due to the ingress of water, so that allowances can be made for such losses. Further, any damage to the skin of such foams may materially accelerate the diminishing buoyancy capacity. Visual inspection does not normally enable a determination to be made as to the relative capacity of the foam, and it therefore may require a check of the air weight of the foam in order to determine its relative floatation or buoyancy capacity.
Moreover, while syntactic foam does provide passive buoyancy, such that its buoyancy level remains relatively constant if buoyancy losses are discounted, its ultimate depth capability is limited. Still further, in an emergency situation, (or indeed a planned dis-connect situation) where it is necessary to rapidly reduce buoyancy of a riser in order to maintain stability of such as a pendulating riser string, it is very expensive to provide means to dump the syntactic foam and especially when it is considered that it is probably or practically impossible to recover the syntactic foam once it has been dumped.
There have also been several floatation air can designs proposed to provide riser string buoyancy for deep sea drilling.
According to one prior art proposal, as disclosed in RHODES et al, U.S. Pat. No. 3,017,934 dated Jan. 23, 1962, a riser is buoyantly supported by a plurality of buoyancy chambers or cans, the chambers or cans being of progressively greater buoyancy per unit length in the direction along the longitudinal axis of the member with increasing water depth. In accordance with one embodiment disclosed by RHODES et al, buoyancy cans are provided which are directed with their open bottoms towards the ocean floor, which cans may be filled from a supply of gas leading to the bottom most can, nearest the ocean floor. A gas conduit allows the gas to flow from a full buoyancy can to the can immediately next above it until all the cans or pods are filled by the gas, which is usually compressed air. Of course, no gas is applied to the next can until the preceding one has been filled.
A more recent proposal is advanced in WATKINS U.S. Pat. No. 3,858,401, dated Jan. 7, 1975, and assigned to Regan Offshore International, Inc. According to WATKINS, floatation for underwater well risers is provided by a plurality of open bottom, buoyancy gas-receiving chambers, which are mounted about the riser conduit. A gas conduit is provided by WATKINS for the delivery of a gas, such as compressed air, to each of the chambers. Gas is admitted to each chamber through an associated valve for each chamber, each of the valves having a floating valve member. Gas supply to a chamber is discontinued when the valve member closes the valve orifice on replacement of the water in the chamber, i.e., when the floating valve member is no longer supported by water. Thus when upper chambers are filled by the gas, and on closing of the valve associated with each chamber, the gas can flow into the next chambers below, instead of gas leaking from the bottoms of the upper chambers.
The proposal by WATKINS suggests embracing the riser by concentrically disposed, open ended chambers. While this system maximizes use of the space for air buoyancy, the system produces a significant pressure differential between the gas--usually air--and the surrounding water which must be accounted for in the structural design of each of the chambers. Furthermore, it is common practice to stack the risers prior to use, such as on the deck of the transport vessel or floating platform. Since the chambers concentrically surround each riser section or unit, the walls of the chamber must, therefore, exhibit the required strength. Thus, the chambers tend to be very heavy, thereby offsetting a significant percentage of the buoyancy gained.
Also, in order to allow for handling and storage, as the containers are attached to each riser section during such handling and storage, the chambers of the WATKINS systems are designed to present a smooth circular outer surface concentric to the axis of a riser. Such a smooth hydrodynamic surface is not desireable due to an increase of drag forces imposed by sub-surface currents and in waves, and the riser may be subject to vortex shedding vibration. In addition, the WATKINS system has certain difficulties due to the possible flexing of the riser conduit within the relatively rigid air chamber or container which surrounds it.
It will, of course, be apparent that a multiplicity of valves and the attendant piping can lead to malfunctioning of at least some of the valves, thereby possibly reducing the efficiency of the system.
The WATKINS patent indicates that the system can be used in drilling operations at up to depths of 6,000 feet (1,829 meters) below the water surface.
SUMMARY OF THE INVENTION:
It is an object of the present invention to provide a buoyancy system for risers which is more reliable and effective than the prior art systems.
A further object of the present invention is to provide a buoyancy system which can be used with risers operating at greater depths below the surface than prior art devices have been capable of operating.
A still further object of the present invention is to provide a buoyancy system which effectively overcomes corrosion, thereby obviating corrosion protection measures normally taken in floatation air chambers.
Yet another object of the present invention is to provide a buoyancy system which is more economical than prior art systems.
It is also an object of the present invention to provide an improved lightweight buoyancy chamber that may be readily installed on and removed from a riser section.
Also, in accordance with this invention, an improved method for achieving buoyancy of large scale underwater risers is provided.
Still another object of this invention is to provide a buoyancy system which may have adjustable buoyancy provisions, as the system is assembled to the riser, and which has re-flood capability so as to cancel the system buoyancy in the event of an emergency situation occuring.
To accommodate the above objects, the present invention comprises a canister which has a floodable, hollow structure which a curved vertical rear wall having a contour approximating in curvature the outer diameter of the riser with which the canister is to be employed, and a curved vertical front wall extending arcuately substantially in parallel with the rear wall. Vertical side walls and top-forming and bottom-forming walls are provided. An internal conduit means provides air communication between superimposed canisters. An air inlet in the bottom wall comprises a tube which extends at least partially into the interior of the canister and which is connected to a source of compressed air supplied to the air inlet from below the canister. At least one water outlet is provided in the bottom of the canister, permitting displacement of the water from the interior thereof upon the injection of compressed air thereinto at a pressure sufficient enough to expel the water from the floodable hollow interior thereof. A port is provided in the conduit means, so that when the water level within the floodable hollow interior reaches the level of the port, air communication is provided through the conduit to the canister next above.
Apart from a number of specific features to be discussed in greater detail hereafter, it should be noted that the present invention comprises also the optional provision, for each canister or for specific canisters--usually at least one for each riser section--of a valve in the top portion of the canister and operable by valve opening means such that when the valve is open the interior of the canister has fluid communication to the sea water in which the canister is immersed so as to be re-floodable through the valve. Generally, such valves are operable together with other valves on other canisters, which may be on the same riser section or on other riser sections, so that mutually connected canisters to the same valve operating means are gang-connected so as to be re-floodable simultaneously.
BRIEF DESCRIPTION OF THE DRAWINGS:
The invention is further described with reference to the accompanying drawings, in which:
FIG. 1 is a perspective view showing a typical buoyancy canister in accordance with one embodiment of the present invention;
FIG. 2 is a cross-sectional view showing the interface between two canisters;
FIG. 3 is a diagrammatic representation of the air charging principle of canisters according to the present invention;
FIG. 4 is a schematic drawing showing the manner of operation of a preferred method of re-flooding;
FIG. 5 is a simplified sketch showing a stowage configuration of a riser-section assembly having canisters according to the present invention assembled thereto;
FIG. 6 is a simplified end view showing random stowage of three riser sections assembled according to this invention;
and
FIGS. 7 and 8 are simplified schematics showing two further interference/collision situations between a canister according to the present invention and an unyielding surface.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to FIG. 1, a riser 10 is shown in phantom outline, having choke and kill lines 12 and 14, to which a plurality of canisters 16 are assembled in the manner discussed hereafter. Generally, the riser is comprised of a plurality of sections, each of which is approximately 50 ft. long, joined by suitable flanges or the like, not shown, as is well known in the art.
The canister 16 is a substantially semi-circular segment, having a generally smooth inner curved vertical wall 20 and a curved outer wall 22. A plurality of ribs 24 may be formed in the outer wall 22, and a notch 26, in which a support tube 28 may be accommodated as discussed hereafter. The canister has vertical side walls 30 and 32, a top forming wall 34 and a bottom forming wall 36; so that the interior of the canister is hollow and as will be discussed in detail hereafter, is floodable. The shape of the cannister is such that it is designed to fit to a riser section at the rear wall 20; and as will be shown hereafter, the substantially semi-circular segment is such that it nearly surrounds one half of the riser section except for the choke and kill lines, and another similar canister placed on the opposite side of the riser provides nearly circumferential coverage of the riser section, at least between the choke and kill line on each side thereof.
Within each canister 16, at a skewed angle between the bottom 36 and top 34, there extends a conduit or cross tube 38, by which air communication from the interior of one canister 16 to the canister next above is accomplished. Generally, the cross tubes 38 are threadably fastened into their respective canisters, between a stub 40 in the bottom wall 36 of a respective canister, and a threaded stub 42 as at 43 in the top wall 34 of the same canister. As discussed hereafter, various cross tubes 38 can be installed in canisters so as to adjust the buoyancy rating of the canister, without the necessity of other major structural changes thereto.
In the usual embodiment, the cross tube 38 extends through the threaded stub 42 and through an opening 44--as seen in FIG. 2--into the interior of the next above canister. Further, the cross-section of the interfitting top and bottom wall portions 34 and 36 of superimposed canisters, as indicated in FIG. 2, includes the threaded boss or stub 42 which extends into a depression 46, for ease of assembly.
It should also be noted that the front and rear walls 22 and 20 of the canister are shown to be curved because of the relationship to the usual configuration of risers, but other configurations may also be designed. Further, as noted, the non-smooth front wall, which may have the ribs or vertical corrugations 24 formed therein, acts to preclude vortex shedding.
In general, the canisters 16 are rotationally moulded--or may be formed using other plastics moulding techniques--of a suitable mouldable plastic material. One such material which has been particularly chosen is available commercially from Phillips Petroleum, under the Trade Mark MARLEX CL100, which is a cross-linked polyethylene. That material has a specific gravity of approximately 0.97, so that it has substantially neutral buoyancy in water. Therefore, the air buoyancy obtained from the canister is not in any way offset by the weight of the canister itself, in water.
Each cross tube 38 has at least one port--usually just one--48 formed in it, near the bottom 36 of the canister. The position of the port above the bottom affects the buoyancy rating of the canister, which is particularly important for riser systems which are intended for operation at depth, as discussed hereafter.
The air charging operation of canisters according to the present invention is as follows:
Air is injected into the bottom of the lowest canister, by means of a suitable air supply 13 from a source of compressed air 15 at the surface. The air supply may be connected to a short stub which extends somewhat into the interior of the canister. In any event, the air is at a pressure which is sufficient to expel water from the canister, which water is expelled from openings in the bottom wall of the canister, such as through the opening 44 past the tube extension extending therethrough.
When the water level in the canister has reached a predetermined level which is determined by the position of the port 48 in the cross tube 38 above the bottom wall 36, air enters the cross tube and travels upwardly into the next above canister. (See FIG. 3.) The same sequence is repeated, working from the lowermost canister to the uppermost canister, until all of the canisters have had the water within the expelled to the level of the port 48 in their respective cross tube 38. Buoyancy is, of course, achieved by this process.
As air flows through the port 48, in the manner indicated by arrow 50 in FIG. 3, a slight resistance to air flow through the port occurs, resulting in a slight loss of air pressure. Since, in any canister, the air pressure within the canister equals the external water pressure at the same depth as the water level inside that canister, the difference in air pressure between two adjacent canisters is equivalent to the difference in the waterhead, approximately 1.5 psi or less, as compared with 22 psi on a conventional steel chamber of the sort referred to above with reference to the WATKINS patent. It can be seen that the pressure differential across the port and cross tube is, therefore, constant, irrespective of operating depth at which the canister is located below the water surface.
Obviously, as the air moves upward through the canisters, its volume increases as pressure reduces. It is therefore necessary to increase the area of the orifice or port 48 to accommodated the larger volume flow at a constant velocity. However, this can be very easily accomplished merely by providing that the ports within the cross tubes 38 are sufficiently large so as to allow a large volume of air flow rate at the available pressure differential. Thus, in a canister which is deep in the water, the water level will only be depressed sufficiently to partially uncover the port, and the orifice area through the port is automatically reduced so as to pass the actual air volume flow rate which exists at that particular ambient pressure. Further, if the air volume flow rate were to be increased slightly, there would be a slight increase in air pressure and the water level in the canister would lower slightly, causing an increase in the orifice area and thereby reducing the orifice restriction so at to reestablish air flow/flow rate/pressure equilibrium. It therefore follows that the ports 48 in each of the cross tubes 38 are such as to be self-compensating for operating depth. It should be noted, also, that as the canisters are not closely nested one to another, there is an essentially unrestricted flow path between them for water expelled from the canisters to flow away from the canisters.
Whether the canisters are filled at the time that they are deployed, or the entire riser is deployed and then the canisters are filled, is dependent upon operational conditions, requirement for achieving buoyancy within a short period of time, available compressor horse power input and pressure and flow output, etc.
Clearly, the buoyancy rating of a canister--either as to its position on a riser string or the amount of buoyancy required in a given situation--may be independent of the size of the canister if the cross tube 38 is replaced by another cross tube having the port 48 at a different level therein with respect to the bottom of the canister.
The necessity for re-flooding of canisters, so as to quickly reduce buoyancy, has been discussed above. Such necessity may, for example, occur where an instability in the riser string becomes apparent when the riser string begins to pendulate. In such instances, provision may be made by permitting one or more of the canisters on each riser section to be reflooded by water. So as to achieve such re-flooding as quickly as possible, a ball valve 52 may be provided on each canister to be flooded, and each of the ball valve 52 is attached to a trigger cable 54 which is operated by a pneumatic cylinder 56. Each of the valves is generally a 1/4 turn ball valve, which when open merely exposes the interior of the canister to the seawater within which it is immersed. Upon operation of the pneumatic cylinder 56, upon command from the surface, all of the valves 52 which are connected to the respective control cable 54 are opened; and the re-flooding time for all of the canisters is only the time required to re-flood any one canister. All of the canisters on a riser section may be connected for re-flood operations, or only certain canisters, depending upon the circumstances and the foreseeable emergency situations where such re-flooding would be necessary.
Referring now to FIG. 5, the assembly of a canister to a riser is noted. In this case, it is the bottom most canister for the particular riser section that is illustrated. As seen also from FIG. 1, the canister 16 extends about the periphery of the riser 10 between the choke and kill lines 12 and 14. Each canister 16 is bolted to a support tube 28, and is secured by brackets such as brackets 58 mounted indents 60. The support tubes 28 extend the full length of each riser section, between riser end flanges 62, and are secured thereto. Thus, each canister is mechanically independently mounted with respect to the riser section 10; and the canisters are spaced apart along the support tube 28 so as to permit independent expansion and contraction of each canister, with temperature, and so as to preclude critical interfaces between canisters. In this manner, buoyancy is transferred to the riser. Needless to say, sections of air line may be installed between the uppermost canister on one riser section and the lowermost canister on the next riser section, in line; and two such connections would be required for each riser section, one on each side.
The handling and stowage of risers on board the surface platforms or vessels may be difficult, and each riser section may be subjected to considerable abuse because of its size and weight. However, the canisters of the subject invention are assembled to the riser section, usually on land, so that the necessity for difficult assembly at sea is precluded. Moreover, in order for the canisters to withstand the abuse of handling and storage, they must be such as to resist the hazards of handling and environmental abuse. Accordingly, it will be seen that the support tubes which are diametrically opposed, and the choke and kill tubes which are diametrically opposed but at right angles to the support tubes, comprise a cage around the riser 10 and within which the canisters are substantially located. However, the outer surfaces of the canisters may extend beyond a direct line drawn between any two cage elements (support tubes 28 and choke and kill lines 12 or 14) so that rather than providing structure which resists or precludes collision and stowage loads, the material of the canisters is such as to yield under an impact or stowage load to the extent which is determined and limited by the cage structure within which the canisters are mounted. For purposes of stowage, where the riser sections are stowed horizontally, stowage ribs 64 are provided, which are bolted to the riser end flanges 62, so that when the riser sections are placed for stowage with the riser end flanges substantially in alignment within a tolerance determined by the length of the stowage ribs 64, a situation may develop as indicated in FIG. 6.
In FIG. 6, there are shown three risers having end flanges 62, and the usual support tubes and choke and kill lines. It will be seen that even in random stowage circumstances, the stowage ribs 64 together with the cage elements which are the support tubes or the choke and kill lines, preclude nesting and interference between the canisters except for very minor amounts as shown by shaded areas 66.
Even in handling, the canisters are yieldable to within limits determined by the geometry of the support cage, which in any event is acceptable within the yield limits of the material of which the canister have been formed. Thus, as shown in FIG. 7, a canister 16A is shown to have yielded in a circumstance where a riser is passing through a circular hole 68, to an extent determined by the point of contact 70 and 72, and as shown by the shaded area 74. Likewise, FIG. 8 shows the worst condition, where canister 16B is impacted upon a straight unyielding surface 76, to the extent that the canister has yielded to behind the contact point 78 and 80 to the extent shown by the shaded area 82. Especially when the preferred material, MARLEX CL100 cross-linked polyethylene is used, such yielding is acceptable, and when the impact force or pressure of the canister on the riser section has been relieved, the canister will regain its original configuration.
There follows a brief comparison of the air-weight advantages which are obtained, and the increased efficiency and cost effectiveness of the employment of canisters according to the present invention when compared with steel chambers or when compared with the air-weight of syntactic foam. TABLE 1, expressed in general terms and in terms of estimated weights per 50 ft. length, illustrates that considerably greater water depth limit is possible for any given vessel which may be restricted by its own stability limit.
TABLE 1______________________________________ Foam or Steel Air Chamber Canister______________________________________Riser weight per joint 5T 5TAir weight of buoyancy system 3.5T 1TWeight = riser + buoyancy 8.5T 6TVessel-stability limit for 1000T 1000Triser stowageNo. of riser joints with 117 166buoyancy systemWater depth limit 5800 ft. 8300 ft.______________________________________
Obviously, the lower structural modulus of the material of the canisters permits flexing of the canisters together with the riser, so that no stresses are caused either in the riser or the buoyancy system. Further, when cross-linked polyethylene is employed, such material is substantially impervious to leakage or corrosion, thereby assuring a maintenance or failure-free buoyancy system for large scale underwater risers.
In certain deep water drilling operations, the surface of the riser pipe may reach temperatures of 80° C. or 85° C. In such cases, it may be necessary to provide a water-duct space between the rear walls 20 of the canisters and the riser wall, so as to permit circulation of cooling water or even seawater therethrough.
The angle at which the cross tube extends within the canisters may be approximately 30° with respect to the vertical. The specific angle is not significant, and may be chosen so as to most easily effect assembly of canisters in a string, and insertion of various cross tubes into the canisters to change the buoyancy rating of any respective canister.
The corrugations on the outer surface of the canisters may be formed other than vertical--i.e., parallel to the axis of the riser--so that a helical strake may be effected by the ribs or corrugations formed in the outer surface of the buoyancy system when it is attached to a riser. In general, as noted, the non-smooth profile creates a three dimensional turbulence which is desirable and efficient in the elimination of vortex shedding vibration of the riser system.
Other changes, amendments and configurations to a buoyancy system and canisters therefor may be readily designed and made, without departing from the spirit and scope of the appended claims.
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A buoyancy system for large scale underwater risers is provided, comprising a plurality of canisters. Each of the canisters extends partially around the circumference of a riser--usually, two canisters and the support structure surround a riser--and a plurality of canisters is associated with each riser section. Air is injected into the lowermost canister or canisters, at a pressure sufficient to displace the contained water within the canister; and when the water level within a canister is lowered sufficiently that a port in a cross connected tube is uncovered, the compressed air enters the tube and travels upwardly to the next canister above, where the unwatering sequence is repeated. Because very great depth can be accommodated--3,000 meters or more--provision is made for reflooding the canisters in the event of an emergency. Additionally, because of pneumatic considerations, different configurations of cross tube are provided for installation in the canisters at varying depths. The support structure for the canisters, and the plastics materials of which the canisters are made--cross-linked polyethylene is preferred--preclude permanent deformation and damage to the canisters during storage or upon impact with an unyielding body or surface.
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