description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
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FIELD OF THE INVENTION
[0001] The present invention relates to an electrospinning process, the resulting electrospun fiber and polymers used in the electrospinning process.
BACKGROUND OF THE INVENTION
[0002] The process of electrospinning uses an electrical charge to form fine fibers. The process consists of a spinneret with a dispensing needle, a syringe pump, a power supply and a grounded collection device. Polymers in solution or as melts are located in the syringe and driven to the needle tip by the syringe pump where they form a droplet. When voltage is applied to the needle, a droplet is stretched to an electrified liquid jet. The jet is elongated continuously until it is deposited on the collector as a mat of fine fibers usually of nanometer-sized dimensions. The resultant fibers are useful in a wide variety of applications such as protective clothing, wound dressing and as supports or carriers for catalyst. To form a fiber, the polymeric melt or solution must have a sufficient viscosity otherwise a drop rather than a liquid jet will form. Typically, thickeners are included in the polymer solution or melt to provide the necessary viscosity. However, thickeners can adversely affect the properties of the resultant fibers and for this reason, their use should be minimized.
SUMMARY OF THE INVENTION
[0003] The present invention provides for a process of electrospinning a fiber from an electrically conductive solution of a polymer in the presence of an electric field between a spinneret and a ground source. The polymer undergoes a crosslinking reaction prior to and during the electrospinning process resulting in a viscosity buildup of the polymer solution enabling fiber formation and minimizing the use of thickeners.
[0004] The invention also provides for the resultant electrospun fiber that contains silane, preferably carboxyl and hydroxyl groups and optionally a nitrogen-containing group such as amine or amide groups. The silane groups provide for crosslinking and viscosity build-up. The carboxyl, hydroxyl, amine and amide groups provide for a hydrogen bonding and viscosity build-up. The carboxyl group, in the form of carboxylic acid, and the nitrogen-containing groups are good electrical charge carrying groups.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 depicts a basic electrospinning system.
[0006] FIG. 2 simulates a scanning electron microscopic (SCM) image of a non-woven mat.
DETAILED DESCRIPTION OF THE INVENTION
[0007] For purposes of the following detailed description, it is to be understood that the invention may assume various alternative variations and step sequences, except where expressly specified to the contrary. Moreover, other than in any operating examples, or where otherwise indicated, all numbers expressing, for example, quantities of ingredients used in the specification and claims are to be understood as being modified in all instances by the term “about”. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties to be obtained by the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard variation found in their respective testing measurements.
[0008] Also, it should be understood that any numerical range recited herein is intended to include all sub-ranges subsumed therein. For example, a range of “1 to 10” is intended to include all sub-ranges between (and including) the recited minimum value of 1 and the recited maximum value of 10, that is, having a minimum value equal to or greater than 1 and a maximum value of equal to or less than 10.
[0009] In this application, the use of the singular includes the plural and plural encompasses singular, unless specifically stated otherwise. In addition, in this application, the use of “or” means “and/or” unless specifically stated otherwise, even though “and/or” may be explicitly used in certain instances.
[0010] The term “polymer” is also meant to include copolymer and oligiomer. The term “acrylic” is meant to include methacrylic and is depicted by (meth)acrylic.
[0011] With reference to FIG. 1 , the electrospinning system consists of three major components, a power supply 1 , a spinneret 3 and an electrically grounded collector 4 . Direct current or alternating current may be used in the electrospinning process. The polymer solution 5 is contained in a syringe 7 . A syringe pump 9 forces the solution through the spinneret 3 at a controlled rate. A drop of the solution forms at the tip of the needle 11 . Upon application of a voltage, typically from 5 to 30 kilovolts (kV), the drop becomes electrically charged. Consequently, the drop experiences electrostatic repulsion between the surface charges and the forces exerted by the external electric field. These electrical forces will distort the drop and will eventually overcome the surface tension of the polymer solution resulting in the ejection of a liquid jet 13 from the tip of the needle 11 . Because of its charge, the jet is drawn downward to the grounded collector 4 . During its travel towards the collector 4 , the jet 13 undergoes a stretching action leading to the formation of a thin fiber. The charged fiber is deposited on the collector 4 as a random oriented non-woven mat as generally shown in FIG. 2 .
[0012] The polymers of the present invention can be acrylic polymers. As used herein, the term “acrylic” polymer refers to those polymers that are well known to those skilled in the art which results in the polymerization of one or more ethylenically unsaturated polymerizable materials. (Meth)acrylic polymers suitable for use in the present invention can be made by any of a wide variety of methods as will be understood by those skilled in the art. The (meth)acrylic polymers can be made by addition polymerization of unsaturated polymerizable materials that contain silane groups, carboxyl groups, hydroxyl groups and optionally a nitrogen-containing group. Examples of silane groups include, without limitation, groups that have the structure Si—X n (wherein n is an integer having a value ranging from 1 to 3 and X is selected from chlorine, alkoxy esters, and/or acyloxy esters). Such groups hydrolyze in the presence of water including moisture in the air to form silanol groups that condense to form —Si—O—Si— groups.
[0013] Examples of silane-containing ethylenically unsaturated polymerizable materials, suitable for use in preparing such (meth)acrylic polymers include, without limitation, ethylenically unsaturated alkoxy silanes and ethylenically unsaturated acyloxy silanes, more specific examples of which include vinyl silanes such as vinyl trimethoxysilane, acrylatoalkoxysilanes, such as gamma-acryloxypropyl trimethoxysilane and gamma-acryloxypropyl triethoxysilane, and methacrylatoalkoxysilanes, such as gamma-methacryloxypropyl trimethoxysilane, gamma-methacryloxypropyl triethoxysilane and gamma-methacryloxypropyl tris-(2-methoxyethoxy) silane; acyloxysilanes, including, for example, acrylato acetoxysilanes, methacrylato acetoxysilanes and ethylenically unsaturated acetoxysilanes, such as acrylatopropyl triacetoxysilane and methacrylatopropyl triacetoxysilane. In certain embodiments, it may be desirable to utilize monomers that, upon addition polymerization, will result in a (meth)acrylic polymer in which the Si atoms of the resulting hydrolyzable silyl groups are separated by at least two atoms from the backbone of the polymer. Preferred monomers are (meth)acryloxyalkylpolyalkoxy silane, particularly (meth)acryloxyalkyltrialkoxy silane in which the alkyl group contains from 2 to 3 carbon atoms and the alkoxy groups contain from 1 to 2 carbon atoms.
[0014] In certain embodiments, the amount of the silane-containing ethylenically unsaturated polymerizable material used in the total monomer mixture is chosen so as to result in the production of a (meth)acrylic polymer comprising silane groups that contain from 0.2 to 20, preferably 5 to 10 percent by weight, silicon, based on the weight of the total monomer combination used in preparing the (meth)acrylic polymer.
[0015] The (meth)acrylic polymer suitable for use in the present invention can be the reaction product of one or more of the aforementioned silane-containing ethylenically unsaturated polymerizable materials and preferably an ethylenically unsaturated polymerizable material that comprises carboxyl such as carboxylic acid groups or an anhydride thereof. Examples of suitable ethylenically unsaturated acids and/or anhydrides thereof include, without limitation, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, maleic anhydride, citraconic anhydride, itaconic anhydride, ethylenically unsaturated sulfonic acids and/or anhydrides such as sulfoethyl methacrylate, and half esters of maleic and fumaric acids, such as butyl hydrogen maleate and ethyl hydrogen fumarate in which one carboxyl group is esterified with an alcohol.
[0016] Examples of other polymerizable ethylenically unsaturated monomers to introduce carboxyl functionality are alkyl including cycloalkyl and aryl(meth)acrylates containing from 1 to 12 carbon atoms in the alkyl group and from 6 to 12 carbon atoms in the aryl group. Specific examples of such monomers include methyl methacrylate, n-butyl methacrylate, n-butyl acrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate and phenyl methacrylate.
[0017] The amount of the polymerizable carboxyl-containing ethylenically unsaturated monomers is preferably sufficient to provide a carboxyl content of up to 55, preferably 15.0 to 45.0 percent by weight based on the weight of the total monomer combination used to prepare the (meth)acrylic polymer. Preferably, at least a portion of the carboxyl groups are derived from a carboxylic acid such that the acid value of the polymer is within the range of 20 to 80, preferably 30 to 70, on a 100% resin solids basis.
[0018] The (meth)acrylic polymer used in the invention also preferably contains hydroxyl functionality typically achieved by using a hydroxyl functional ethylenically unsaturated polymerizable monomer. Examples of such materials include hydroxyalkyl esters of (meth)acrylic acids having from 2 to 4 carbon atoms in the hydroxyalkyl group. Specific examples include hydroxyethyl(meth)acrylate, hydroxypropyl(meth)acrylate and 4-hydroxybutyl (meth)acrylate. The amount of the hydroxy functional ethylenically unsaturated monomer is sufficient to provide a hydroxyl content of up to 6.5 such as 0.5 to 6.5, preferably 1 to 4 percent by weight based on the weight of the total monomer combination used to prepare the (meth)acrylic polymer.
[0019] The (meth)acrylic polymer optionally contains nitrogen functionality introduced from a nitrogen-containing ethylenically unsaturated monomer. Examples of nitrogen functionality are amines, amides, ureas, imidazoles and pyrrolidones. Examples of suitable N-containing ethylenically unsaturated monomers are: amino-functional ethylenically unsaturated polymerizable materials that include, without limitation, p-dimethylamino ethyl styrene, t-butylaminoethyl(meth)acrylate, dimethylaminoethyl(meth)acrylate, diethylaminoethyl(meth)acrylate, dimethylaminopropyl(meth)acrylate and dimethylaminopropyl(meth)acrylamide; amido-functional ethylenically unsaturated materials that include acrylamide, methacrylamide, n-methyl acrylamide and n-ethyl(meth)acrylamide; urea functional ethylenically unsaturated monomers that include methacrylamidoethylethylene urea.
[0020] If used, the amount of the nitrogen-containing ethylenically unsaturated monomer is sufficient to provide nitrogen content of up to 5 such as from 0.2 to 5.0, preferably from 0.4 to 2.5 percent by weight based on weight of a total monomer combination used in preparing the (meth)acrylic polymer.
[0021] Besides the polymerizable monomers mentioned above, other polymerizable ethylenically unsaturated monomers that may be used to prepare the (meth)acrylic polymer. Examples of such monomers include poly(meth)acrylates such as ethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetraacrylate; aromatic vinyl monomers such as styrene, vinyl toluene and alpha-methylstyrene; monoolefinic and diolefinic hydrocarbons, unsaturated esters of organic and inorganic acids and esters of unsaturated acids and nitrites. Examples of such monomers include 1,3-butadiene, acrylonitrile, vinyl butyrate, vinyl acetate, allyl chloride, divinyl benzene, diallyl itaconate, triallyl cyanurate as well as mixtures thereof. The polyfunctional monomers, such as the polyacrylates, if present, are typically used in amounts up to 20 percent by weight. The monfunctional monomers, if present, are used in amount up to 70 percent by weight; the percentage being based on weight of the total monomer combination used to prepare the (meth)acrylic polymer.
[0022] The (meth)acrylic polymer is typically formed by solution polymerization of the ethylenically unsaturated polymerizable monomers in the presence of a polymerization initiator such as azo compounds, such as alpha, alpha′-azobis(isobutyronitrile), 2,2′-azobis(methylbutyronitrile) and 2,2′-azobis(2,4-dimethylvaleronitrile); peroxides, such as benzoyl peroxide, cumene hydroperoxide and t-amylperoxy-2-ethylhexanoate; tertiary butyl peracetate; tertiary butyl perbenzoate; isopropyl percarbonate; butyl isopropyl peroxy carbonate; and similar compounds. The quantity of initiator employed can be varied considerably; however, in most instances, it is desirable to utilize from 0.1 to 10 percent by weight of initiator based on the total weight of copolymerizable monomers employed. A chain modifying agent or chain transfer agent may be added to the polymerization mixture. The mercaptans, such as dodecyl mercaptan, tertiary dodecyl mercaptan, octyl mercaptan, hexyl mercaptan and the mercaptoalkyl trialkoxysilanes such as 3-mercaptopropyl trimethoxysilane may be used for this purpose as well as other chain transfer agents such as cyclopentadiene, allyl acetate, allyl carbamate, and mercaptoethanol.
[0023] The polymerization reaction for the mixture of monomers to prepare the acrylic polymer can be carried out in an organic solvent medium utilizing conventional solution polymerization procedures which are well known in the addition polymer art as illustrated with particularity in, for example, U.S. Pat. Nos. 2,978,437; 3,079,434 and 3,307,963. Organic solvents that may be utilized in the polymerization of the monomers include virtually any of the organic solvents often employed in preparing acrylic or vinyl polymers such as, for example, alcohols, ketones, aromatic hydrocarbons or mixtures thereof. Illustrative of organic solvents of the above type which may be employed are alcohols such as lower alkanols containing 2 to 4 carbon atoms including ethanol, propanol, isopropanol, and butanol; ether alcohols such as ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, and dipropylene glycol monoethyl ether; ketones such as methyl ethyl ketone, methyl N-butyl ketone, and methyl isobutyl ketone; esters such as butyl acetate; and aromatic hydrocarbons such as xylene, toluene, and naphtha.
[0024] In certain embodiments, the polymerization of the ethylenically unsaturated components is conducted at from 0° C. to 150° C., such as from 50° C. to 150° C., or, in some cases, from 80° C. to 120° C.
[0025] The polymer prepared as described above is usually dissolved in solvent and typically has a resin solids content of about 15 to 80, preferably 20 to 60 percent by weight based on total solution weight. The molecular weight of the polymer typically ranges between 3,000 to 1,000,000, preferably 5,000 to 100,000 as determined by gel permeation chromatography using a polystyrene standard.
[0026] For the electrospinning application, the polymer solution such as described above can be mixed with water to initiate the crosslinking reaction and to build viscosity necessary for fiber formation. Typically about 5 to 20, preferably 10 to 15 percent by weight water is added to the polymer solution with the percentage by weight being based on total weight of the polymer solution and the water. Preferably a base such as a water-soluble organic amine is added to the water-polymer solution to catalyze the crosslinking reaction. Optionally a thickener such as polyvinyl pyrrolidone, polyvinyl alcohol, polyvinyl acetate, polyamides and/or a cellulosic thickener can be added to the electrospinning formulation to better control its viscoelastic behavior. If used, the thickener is present in amounts no greater than 20 percent by weight, typically from 1 to 6 percent by weight based on weight of the polymer solution.
[0027] The electrospinning formulation prepared as described above is then stored to permit the viscosity to build to the crosslinking reaction. When the viscosity is sufficiently high but short of gelation, the formulation is subjected to the electrospinning process as described above.
[0028] Typically, the viscosity is at least 5 and less than 2,000, usually less than 1,000, such as preferably within the range of 50 to 250 centistokes for the electrospinning process. A Bubble Viscometer according to ASTM D-1544 determines the viscosity. The time for storing the electrospinning formulation will depend on a number of factors such as temperature, crosslinking functionality and catalyst. Typically, the electrospinning formulation will be stored for as low as one minute up to two hours.
[0029] When subject to the electrospinning process, the formulations described above typically produce fibers having a diameter of up to 5,000, such as from 5 to 5,000 nanometers, more typically within the range of 50 to 1,200 nanometers, such as 50 to 700 nanometers. The fibers also can have a ribbon configuration and in this case diameter is intended to mean the largest dimension of the fiber. Typically the width of the ribbon shaped fibers is up to 5000 such as 500 to 5000 nanometers and the thickness up to 200 such as 5 to 200 nanometers.
[0030] The following examples are presented to demonstrate the general principles of the invention. However, the invention should not be considered as limited to the specific examples presented. All parts are by weight unless otherwise indicated.
EXAMPLES A, B and C
Synthesis of Acrylic Silane Polymers
[0031] For each of Examples A to C in Table 1 below, a reaction flask was equipped with a stirrer, thermocouple, nitrogen inlet and a condenser. Charge A was then added and stirred with heat to reflux temperature (75° C.-80° C.) under nitrogen atmosphere. To the refluxing ethanol, charge B and charge C were simultaneously added over three hours. The reaction mixture was held at reflux condition for two hours. Charge D was then added over a period of 30 minutes. The reaction mixture was held at reflux condition for two hours and subsequently cooled to 30° C.
[0000]
TABLE 1
Example A
Example B
Example C
Charge A (weight in grams)
Ethanol SDA 40B 1
360.1
752.8
1440.2
Charge B (weight in grams)
Methyl Methacrylate
12.8
41.8
137.9
Acrylic acid
8.7
18.1
34.6
Silquest A-174 2
101.4
211.9
405.4
2-hydroxylethylmethacrylate
14.5
0.3
0.64
n-Butyl acrylate
0.2
0.3
0.64
Acrylamide
7.2
—
—
Sartomer SR 355 3
—
30.3
—
Ethanol SDA 40B
155.7
325.5
622.6
Charge C (weight in grams)
Vazo 67 4
6.1
12.8
24.5
Ethanol SDA 40B
76.7
160.4
306.8
Charge D (weight in grams)
Vazo 67
1.5
2.1
6.1
Ethanol SDA 40B
9.1
18.9
36.2
% Solids
17.9
19.5
19.1
Acid value
51.96
45.64
45.03
(100% resin solids)
Mn
—
3021 5
5810
1 Denatured ethyl alcohol, 200 proof, available from Archer Daniel Midland Co.
2 gamma-methacryloxypropyltrimethoxysilane, available from GE silicones.
3 Di-trimethylolpropane tetraacrylate, available from Sartomer Company Inc.
4 2,2′-azo bis(2-methyl butyronitrile), available from E.I. duPont de Nemours & Co., Inc.
5 Mn of soluble portion; the polymer is not completely soluble in tetrahydrofuran.
EXAMPLES 1, 2 AND 3
Acrylic-Silane Nanofibers
Example 1
[0032] The acrylic-silane resin solution from Example C (8.5 grams) was blended with polyvinylpyrrolidone (0.2 grams) and water (1.5 grams). The formulation was stored at room temperature for 215 minutes. A portion of the resulting formulation was loaded into a 10 ml syringe and delivered via a syringe pump at a rate of 1.6 milliliters per hour to a spinneret (stainless steel tube 1/16-inch outer diameter and 0.010-inch internal diameter). This tube was connected to a grounding aluminum collector via a high voltage source to which about 21 kV potential was applied. The delivery tube and collector were encased in a box that allowed nitrogen purging to maintain a relative humidity of less than 25%. Ribbon shaped nanofibers having a thickness of about 100-200 nanometers and a width of 500-700 nanometers were collected on the grounded aluminum panels and were characterized by optical microscopy and scanning electron microscopy.
Example 2
[0033] The acrylic-silane resin solution from Example B (8.5 grams) was blended with polyvinylpyrrolidone (0.1 grams) and water (1.5 grams). The formulation was stored at room temperature for 210 minutes. A portion of the resulting solution was loaded into a 10 ml syringe and delivered via a syringe pump at a rate of 0.2 milliliters per hour to the spinneret of Example 1. The conditions for electrospinning were as described in Example 1. Ribbon shaped nanofibers having a thickness of 100-200 nanometers and a width of 900-1200 nanometers were collected on grounded aluminum foil and were characterized by optical microscopy and scanning electron microscopy.
Example 3
[0034] The acrylic-silane resin from Example A (8.5 grams) was blended with polyvinylpyrrolidone (0.1 grams) and water (1.5 grams). The formulation was stored at room temperature for 225 minutes. A portion of the resulting solution was loaded into a 10 ml syringe and delivered via a syringe pump at a rate of 1.6 milliliters per hour to the spinneret as described in Example 1. The conditions for electrospinning were as described in Example 1. Ribbon shaped nanofibers having a thickness of 100-200 nanometers and a width of 1200-5000 nanometers were collected on grounded aluminum foil and were characterized by optical microscopy and scanning electron microscopy. A sample of the nanofibers was dried in an oven at 110° C. for two hours. No measurable weight loss was observed. This indicates the nanofibers were completely crosslinked.
[0035] Whereas particular embodiments of this invention have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details of the present invention may be made without departing from the invention as defined in the appended claims. | A method for electrospinning polymer fibers and the resultant electrospun fibers are disclosed. In the electrospinning method, the polymer undergoes a crosslinking reaction prior to and during the electrospinning process. | 8 |
[0001] FIELD OF THE INVENTION
[0002] This invention relates to a system for determining the condition of a patient's heart.
BACKGROUND OF THE INVENTION
[0003] The use of electrocardiographic (ECG) information to detect ischaemic heart disease (IHD) is not new. The standard twelve lead ECG has been used by clinicians for decades for early detection of ischaemic events. The procedure involves the use of 10 appropriately placed electrodes and suitable instrumentation amplifiers to acquire 12 separate ECG signals. These signals are then interpreted either visually or by automated software to identify ischaemic signs. Unfortunately, the area of the torso covered by these 10 electrodes is insufficient to detect ischaemic events from all areas of the heart. This means that the standard twelve lead ECG in many instances fails to provide unequivocal diagnosis.
[0004] An improved method is the use of unipolar body surface mapping (BSM) which uses a multitude of electrodes (typically between 32 and 200 electrodes) distributed across both the anterior and posterior surface of the torso. With such a system the amount of information being presented to the user is impractical. Furthermore, with large numbers of electrodes, the system requires a significant amount of time to be applied to the patient. One approach of particular interest is by Lux et al. “Redundancy reduction for improved display and analysis of Body Surface Potential Maps I spatial compression”, Circulation Res, Vol. 49, 186-196; where a Karhunen-Loeve method is described which allows a minimal lead set to be recorded and then later expanded mathematically to a more detailed lead set.
[0005] Investigations concerning the analysis of such BSM's both directly recorded and expanded mathematically has resulted in various different analysis techniques. All of these however are essentially enhancements to the analysis techniques used to interpret the standard 12 Lead ECG. BSM information is unique in that it provides an overall body surface electrical pattern. This pattern is distinctive and must be analyzed in a way which takes advantage of the information contained within it.
[0006] The use of vectors in ECG interpretation is known, the most famous being Vectorcardiographic systems which are no longer common. All of these vector analysis techniques however concentrate upon the discrete amplitude of the vector drawn between a maximum and a minimum point of electrical potential. One such system is disclosed in European Patent Specification EP-A-0512 719 B1 where a system is described for detecting coronary artery disease by use of a discriminant function. Here one such parameter which could be analyzed is the overall QRST vector. This would be a vector drawn between the maximum and the minimum point of a QRST isointegral BSM.
[0007] The use of discriminant functions as described above has been for many years arguably the best method for analyzing the parameters and features extracted from BSM's. One notorious problem with a discriminant function approach is the lack of determinism associated with such a technique. Given any particular case or set of parameters it is very difficult to see what output a given function will provide and given an output it is very difficult to determine how the function arrived at that decision.
[0008] The use of a more conventional decision tree approach has not been considered appropriate since the problem possesses so many dimensions. Having obtained a decision node (using binary comparison of a given parameter to a preset threshold), which will reliably and accurately detect one given patient condition, it is later found that the same decision fails when complicated by other real life conditions. For example, having devised a decision tree which can be useful in detecting acute myocardial infarction occurring in all areas of the myocardium, this same algorithm then fails when there are two areas of the myocardium infarcting at the same time, when the heart is abnormally shaped due for instance to hypertrophy or when the infarct is complicated by a disorder of the conduction system.
SUMMARY OF THE INVENTION
[0009] It is an object of the present invention to provide a means for analyzing cardiac information which can provide an improved diagnostic capability with a clearly traceable path to the resulting decision.
[0010] Accordingly, the invention provides a system for determining the condition of a patient's heart, comprising:
[0011] (a) a plurality of electrodes each capable of detecting the electrical activity associated with a heartbeat of the patient and producing a corresponding cardiac signal,
[0012] (b) means for converting the cardiac signals into digital form, and
[0013] (c) data processing means programmed to:
[0014] (1) process the digital cardiac signals to determine a plurality of parameters of the patient's heartbeat,
[0015] (2) determine the condition of the patient's heart using a binary decision tree algorithm, such algorithm having a plurality of decision nodes each of which makes a decision based upon the value(s) of a respective subset of the parameters, the decision criterion of at least one of the said decision nodes being modified according to the value of at least one parameter not of the respective subset, and
[0016] (3) provide an output indicative of the condition of the patient's heart so determined.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which:
[0018] [0018]FIG. 1 is a schematic view of a system according to one embodiment;
[0019] [0019]FIG. 2 is a block diagram of the storage, processing and display unit of FIG. 1;
[0020] [0020]FIG. 3 is a flowchart of the program stored in the unit of FIG. 2; and
[0021] [0021]FIG. 4 is an example of spatial resultant vectors (static vectors) measured on the body surface with reference to the Wilson Central Terminal (WCT).
DETAILED DESCRIPTION OF THE INVENTION
[0022] Referring to FIGS. 1 - 4 , in one embodiment a system according to the invention includes a two-dimensional array 10 of a plurality of ECG electrodes removably attachable to a human patient's torso 15 . As shown in FIG. 1 the electrodes are attached to the anterior surface of the torso but they can extend substantially fully around the torso. The number of electrodes in the array can typically vary from 20 to 100; in the present case it is assumed there are 96 electrodes. The array 10 also includes right arm (RA), left arm (LA), right leg (RL), and left leg (LL) electrodes and may be constructed as described in International Application Number PCT/1B95/01043 (WO96/14015).
[0023] Each electrode is capable of detecting the electrical activity associated with the patient's heartbeat and producing a corresponding cardiac signal, and it will be appreciated that each electrode in the array 10 , although detecting the same activation of the heartbeat at any given instant, receives the signal with a different voltage having regard to its different spatial position relative to the heart. Since the electrode signal typically has a strength in millivolts it requires amplification prior to further processing. This is achieved in an interface unit 11 which performs front end amplification and analogue-to-digital (A/D) data conversion. The unit 11 may be constructed as described with reference to FIG. 4 of International Application Number PCT/1B97/01631 (W098/26712).
[0024] Briefly, however, the total set of 96 signals from the array 10 is divided into six channels of 16 signals per channel. Each channel contains 16 banks of amplification, filtering and sample/hold devices, and a respective 16-to-1 analogue signal multiplexer in each channel is used to sequentially switch through each of the 16 signals during each sample/hold period to enable a single channel digital conversion to be used. A microcontroller controls the process of freezing the 16 analogue signals in each channel and during each sample/hold period the analogue multiplexer is selected 16 times with each step sequentially switching one of the 16 signals through to an A/D converter. The sampling frequency is at least 500 Hz and preferably at least 1 khz.
[0025] The interface unit 11 , therefore, produces successive sets of 96 sampled and analogue to digital converted signal values, each set having been derived during a respective sample/hold period and therefore constituting a “snapshot” of the electrode voltages at the respective sampling instant. With a sampling frequency of 1 KHz, 1000 sets of 96 signals will be produced per second.
[0026] The digitized cardiac signals are passed via a direct digital link 13 to a storage, processing and display unit 12 , FIG. 2, comprising a microprocessor 22 , a storage device 23 , an electronic display device, such as a CRT monitor 24 , a printer 25 and a user interface, such as a keyboard 26 . The microprocessor 22 polls each of the channels to transfer sampled data into the storage device 23 . In particular, once patient hook-up is satisfactorily completed, the microprocessor 22 stores a pre-selected time frame (typically 5 seconds) of all the channels into the storage device 22 . The microprocessor 22 is programmed to process the stored digital data according to the flowchart shown in FIG. 3.
[0027] First (Step 100 ,) the program extracts certain parameters from the digital signals. In the present embodiment these are QRS Integral, ST-T Integral, STO ms Isopotential, ST60 ms Isopotential, ST100 ms Isopotential and V Symmetry . Apart from V Symmetry , these parameters are well known in the art and methods for their extraction are also well known.
[0028] The parameter V Symmetry is given by:
V
Symmetry
=V
Max
−V
Min
[0029] where V Max is the maximum ST60 ms isopotential static vector and V Min is the minimum ST60 ms isopotential static vector, ST60 ms isopotential being defined as the isopotential map constructed from all electrode locations at the time instant 60 milliseconds after the ‘J’ point in the ECG cycle. These vectors are described in International Application Number PCT/EP98/01446 (WO 98/4 0010).
[0030] Referring to FIG. 4, it can be seen that the V Max vector is the vector drawn from the WCT to the overall maximum location on the body surface and V Min is the vector drawn from the WCT to the overall minimum location. The length shown in FIG. 4 is for demonstration only and in reality does not reflect the distance between the WCT and the body surface, but rather the magnitude of the electrical signal detected on the body surface. The vectors are referred to as “static” to denote that the vectors are either snapshots or averages of dynamically changing information.
[0031] Having extracted these parameters, the program implements a binary decision tree algorithm comprising, in one embodiment, six binary decision nodes 102 to 112 which test as follows:
Node 102 Ischaemic/Normal? Node 104 Normal/Abnormal Conduction? Node 106 AMI (Acute Myocardial Infarction) with Conduction Disorder? Node 108 Classic AMI? Node 110 AMI with LVH (Left Ventricular Hypertrophy)? Node 112 AMI with ST Depression?
[0032] As indicated by the dashed line on the RHS of FIG. 3, at each node 102 - 112 the respective test is made on the basis of the value(s) of one or more of the parameters QRS Integral, ST-T Integral, STO ms Isopotential, ST60ms Isopotential and ST100ms Isopotential, the relevant parameter(s) being compared with respective threshold(s) associated with the node to determine the binary outcome, yes (Y) or no (N), of the node. For example, node 108 tests to see if both STOms Isopotential and ST6Oms Isopotential are above certain respective thresholds, node 110 tests to see if both ST6Oms Isopotential and ST-T Integral are below certain respective thresholds, while node 112 tests to see if both STOms Isopotential and ST60ms Isopotential are below certain respective thresholds. The nature of the tests made at the nodes 102 - 112 will be known to those skilled in the art.
[0033] By following through the logic of the flowchart, it will be seen that, depending upon the decisions at the nodes, the program will output “Normal” (Step 120 ) indicating that the heart is normal, “AMI” (Step 122 ) indicating Acute Myocardial Infarction or “Other” (Step 124 ) indicating some other abnormality. The output is displayed in human-readable form on the CRT monitor 24 , FIG. 2, or may be printed out or otherwise displayed.
[0034] In order to improve the accuracy of the diagnosis, the static vector symmetry, which changes depending upon the condition of the heart, is used to adaptively control the thresholds used by the decision algorithm. Thus, in the present embodiment and as indicated by the dashed line on the LHS of FIG. 3, the parameter thresholds associated with each of the nodes 108 , 110 and 112 are varied according to the magnitude of V Symmetry . This may be achieved by storing, e.g. in a look-up-table, a number of different thresholds for each parameter ST-T Integral, STOms Isopotential and/or ST60ms Isopotential tested by the node and selecting a particular one of the thresholds according to the magnitude of V Symmetry .
[0035] In a simple case there will be two thresholds stored for each parameter tested by a node, and one or other will be selected according to whether V Symmetry is itself above or below a certain threshold (i.e. above or below a certain symmetry level). However, since V Symmetry is a continuously variable parameter, the nodes could use a function f(V Symmetry ) to select the parameter threshold.
[0036] It should be noted that unlike a discriminant function or an artificial neural network (ANN) which are probalistic, the adaptive algorithm described above is deterministic in that for any given case it is easy to determine how the algorithm will perform and also that given an output it is very easy to determine how the algorithm arrived at its decision.
[0037] The above is given only as an example of the invention, and modifications are possible. For example, the binary decision tree algorithm may be more or less complex than that shown, and may use more or less, and/or different, parameters in its operation. Thus, the V Max and V Min vectors used to derive V Symmetry are only given by way of example since similar vectors usable in the invention can be constructed from QRS isointegral maps, STT isointegral maps, as well as STOms isopotential and ST100ms isopotential maps. Also, although only one parameter, V Symmetry has been used to adaptively control certain of the decision nodes, in general, and depending on the complexity of the binary decision tree algorithm, more than one parameter can be used to adaptively control the nodes. This may include using more than one parameter to adaptively control an individual node or using different parameters to adaptively control different nodes.
[0038] In addition, one or more parameters may be used to determine which of the other parameters are used at a decision node. For example, in FIG. 3, node 110 may use the parameters ST-T Integral and ST60ms Isopotential if V Symmetry is below a certain value and use the parameters ST-T Integral and STOms Isopotential if V Symmetry is above that value.
[0039] Furthermore, the decision thresholds for the chosen parameters may themselves be varied according to the value of another parameter. For example, in the case above, the value of V Symmetry is used to select which two out of three parameters to use at, decision node 110 . The value of the QRS integral may then be used to determine the decision thresholds to apply to those selected parameters.
[0040] Having thus described at least one illustrative embodiment of the invention, various alterations, modifications and improvements will readily occur to those skilled in the art. Such alterations, modifications and improvements are intended to be within the scope and spirit of the invention. Accordingly, the foregoing description is by way of example only and is not intended as limiting. The invention's limit is defined only in the following claims and the equivalents thereto. | A system for determining the condition of a patient's heart comprises a plurality of electrodes for producing cardiac signals and means for converting the cardiac signals into digital form. Data processing means is programmed to process the digital cardiac signals to detemine a plurality of parameters of the patient's heartbeat and determine the condition of the patient's heart using a binary decision tree algorithm. The algorithm has a plurality of decision nodes each of which makes a decision based upon the value(s) of a subset of the parameters, the decision criterion of at least one of the said decision nodes being modified according to the value of at least one parameter not of the subset. In addition, at at least one node, the respective subset of parameters may be determined according to the value of at least one parameter not of the subset. | 0 |
RELATED U.S. PATENT APPLICATION
[0001] This Continuation Application claims the benefit and priority of the co-pending, commonly-owned US Patent Application with Attorney Docket No. PALM-3641.5G.CON, application Ser. No. 10/951,537, filed on Sep. 27, 2004, by Wong et al., and titled “OPTICAL SENSOR BASED USER INTERFACE FOR A PORTABLE ELECTRONIC DEVICE,” which is a Continuation Application that claims the benefit of the commonly-owned U.S. patent application Ser. No. 09/871,375 filed on May 30, 2001, now issued as a U.S. Pat. No. 6,816,154, by Wong et al., and titled “Optical Sensor Based User Interface For a Portable Electronic Device,” which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to the field of portable electronic devices such as personal digital assistants or pentop computer systems. Specifically, the present invention relates to an apparatus and method for utilizing an optical sensor based user interlace for registering user input.
[0004] 2. Related Art
[0005] Portable computer systems, such as “palmtop” computer systems, or personal digital assistants (PDA) have become commonplace and extraordinarily useful electronic devices. A palmtop computer system includes a hand-held device and a cradle device to which it ports and which connects and synchronizes it to other computers. Owing to their portability, capability, and versatility, hand-held computer devices are designed to be used in a wide variety of environments, for many applications.
[0006] Portable computers are usually robustly packaged devices, designed for simplicity of operation and durability. Few penetrations expose their interiors, wherein their operational components reside. However, function/field selection buttons, on/off, interconnection, and other switching components expose the interior to some degree to allow accessibility for switching and other operations. Mechanical switching components, such as switches, buttons, and, especially, thumbwheels and associated potentiometers, variable capacitors, and the like, while ostensibly durable, have definite physical vulnerabilities and finite operational lifespans. Further, although designed for operational simplicity, using a portable computer system by manipulating these switching components requires some degree of tactile skill.
[0007] Portable computer systems may be used in harsh environments, unlike other computers designed with less of a degree of mobility, such as desktop computer systems. For example, desktop computer systems most often find application in offices, classrooms, and similar milieus, with environments subject to some relatively satisfactory degree of control. Portable computer systems, on the other hand, while indeed they may also be used in such environments, are designed for use almost anywhere, contributing to their versatility and usefulness, e.g., a vehicle, outside, etc.
[0008] Portable computer systems are frequently and reliably deployed in-transit, in private and public modes of transportation of almost every kind. Portable computer systems find operational deployment in the field in, for example, industrial, urban, marine, construction, and even military application. Under these circumstances, their operational environment may vary widely and change rapidly, often subject to little or no control. These environments may also be quite rugged, extreme, wet, dirty, contaminated, and dusty.
[0009] When their operational environment is rugged, extreme, wet, dirty, dusty, or contaminated, operation of the portable computer system may contribute to or cause internal contamination or physical damage. Environmental contaminants such as moisture, dirt, dust, chemicals, and the like, may penetrate even the small openings for exposure of switching components to user manipulation, especially thumbwheels and their associated potentiometers. Once inside the portable computer, or a connector or button, they may cause fouling, damage, or destruction of its internal microelectronic and other components. And while switching components may be designed for durability, they all display some degree of physical vulnerability and aging degradation characteristics.
[0010] Although designed for operational simplicity, portable computer systems require same dexterity to operate properly. To operate the portable computer system to accomplish these tasks, controls and switching components must be manipulated. Manipulation enables, for example, choosing a screen, scrolling through various screens, selecting an on-screen icon, field, menu, listing, or data entry, or “writing to” or “typing on” an on-board touch-sensitive writing pad-like surface with a stylus, or other touch-enabling probe.
[0011] However, also owing to their versatility and portability, portable computer systems may be operated by a user who is purposefully multi-tasking, or otherwise engaged in other activities besides operating the portable computer. Portable computer systems are routinely utilized to, for example, access telephone numbers from an on-board telephone list, reminders from an on-board list of memoranda, gaming, portable internet browsing or email access, and a host of other computer-enabled and/or enhanced activities, all while the user is fully engaged in some other task.
[0012] When the circumstances under which portable computer systems are used become complex and distracting, operation of the portable computer system may become difficult. This may detract from the computing experience of the user, it may cause errors or loss of data, and/or require operational stops to be repeated. This is inconvenient and costly.
[0013] Conventionally, an approach to solving the problem of internal exposure of portable computers to environmental contaminants has been to attempt to minimize the interior exposure. This has been accomplished in one attempted solution by reducing the number and size of penetrations through their cases, and to seal the penetrations. Reducing the number of penetrations requires a concomitant reduction in the number of switching components. This requires switching components to have multiple, selectable functions. However, this has the undesirable effect of increasing operational complexity. Sealing the penetrations increases packaging complexity and increases unit costs, and interferes with switching component operations.
[0014] Conventionally, an approach to solving the problem of making portable computer device operation less complicated for engaged users, especially those simultaneously engaged in activities besides computing, has been to simplify the computer-user interface. This has been attempted, in one approach, by adding switching components. However, this has the undesirable effect of increasing package penetration with resulting increased internal exposure of the computer device to environmental contaminants.
[0015] Another conventional method of attempting to solve this problem has been-to change the characteristics of the switching components. For instance, in one approach, a “jog wheel,” “thumb wheel,” or similar of rotary dial-type mechanism. However, this particular approach is especially vulnerable to environmental contamination problems.
[0016] Rotary dial-type mechanisms rotate about a shaft, which penetrates the package of the portable computer system to actuate the rotationally variable electrical components contained within. This shaft penetration is potentially a route for incursion of environmental contamination to the sensitive interior of the portable computer device. Exacerbating this problem is the size of the rotary dial, itself. Normally, such dials are larger than other switches penetrating the portable computer device package. Further, the dial has a lower surface facing the portable computer device package, yet not quite abutting it.
[0017] The space beneath the dial, between the dial and the portable computer device package is especially susceptible to the accumulation of moisture, detritus, dirt, dust, debris, oil, and chemicals. This is particularly problematic for three reasons. First, because the potential environmental contaminants remain there, proximate to a potential incursion route to the portable computer system interior even after the portable computer system is removed from the contaminating environment. Second, it increases the time of exposure to the potential environmental contaminants, thus increasing the probability of incursion. Third, the space between the dial and the portable computer device package is very hard to clean, and attempts to clean it may actually force contaminants into the shaft incursion route and into the interior of the portable computer.
[0018] The conventional art is problematic therefore for two related reasons. First, because attempts to promote ease of use of portable computer devices threaten increased risk of internal exposure thereof to environmental contamination. Second, because attempts to reduce risk of internal exposure of portable computer devices to environmental contamination complicate their use and increase their cost.
[0019] What is needed is a method and/or apparatus that promotes a positive computing experience for users of portable computer systems and/or increases overall durability an War Longevity thereof. What is also needed is a method and/or apparatus that promotes the operational simplicity of portable computer systems. Further, what is needed is a method and/or apparatus that enables efficient portable computer function, field, and data selection, gaming, input, interconnection, and other switching-related functions without exposing the portable computer interior to any degree to incursion of environmental contamination. Further still, what is needed is a method and/or apparatus that achieves the foregoing accomplishments while allowing the full range of both portability and environmental exposure, and range and ease of use characteristic of portable computer devices, yet without complete redesign.
SUMMARY OF THE INVENTION
[0020] An apparatus and method are described herein, which simultaneously promote a positive computing experience for users of portable computer systems and increases overall durability and longevity thereof. An apparatus and method are described herein, which also promote the operational simplicity of portable computer systems. Further, an apparatus and method are described herein, which enable efficient portable computer function, field, and data selection, gaming, input, interconnection, and other switching-related functions without exposing the portable computer interior to any degree to incursion of environmental contamination. Further still, an apparatus and method are described herein, which achieve the foregoing accomplishments while allowing the full range of bath portability and environmental exposure, and range and ease of use characteristic of portable computer devices, yet without completely redesigning portable computer system packaging and operation.
[0021] In one embodiment, the present invention is directed to an apparatus and method, which promote a positive computing experience for users of portable computer systems. Simultaneously, the present embodiment promotes overall portable computer device durability and longevity. In the present embodiment, an optical apparatus and a method for using it enhance the experience of a user attempting to compute. Further, the optical apparatus is much more durable and long-lasting than mechanical switch and dial type devices it may replace.
[0022] In one embodiment, the present invention is directed to an apparatus and method, which also promote the operational simplicity of portable computer systems. In the present embodiment, an optical apparatus and method of using it simplify operations such as function, field, and data selection, gaming, input, interconnection, browsing, scrolling, and other switching-related functions. This promotes use of the device while engaged in activities beside computing, enhancing versatility.
[0023] In one embodiment, the present invention is directed to an apparatus and method, which enable efficient portable computer device function, field, and data selection, gaming, input, interconnection, and other switching-related functions without exposing the portable computer interior to any degree to incursion of environmental contamination. In the present embodiment, an optical apparatus obviates openings in portable computer which were conventionally required, in the prior art, for mechanically manipulated switches. Advantageously, this deters encroachment of environmental contaminants into the interior of the portable computer device.
[0024] In one embodiment, the present invention is directed to an apparatus and method, which achieve the foregoing advantages while allowing the full range of both portability and environmental exposure, and range and ease of use characteristic of portable computer devices, yet without completely redesigning portable computer system packaging and operation. The same basic portable computer device package is still applicable. In the present embodiment, an optical apparatus obviating mechanically manipulated switch openings deters incursion of contaminants into portable computer device interiors. With no package redesign, portable computer devices may continue to be deployed in all environments, now with greatly reduced risk of damage and/or contamination.
[0025] These and other objects and advantages of the present invention will become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiments, which are illustrated in the various drawing figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The accompanying drawings which are incorporated in and form a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention,
[0027] FIG. 1 is a system illustration of a portable computing system connected to other computer systems and the Internet via a cradle device.
[0028] FIG. 2A is a perspective illustration of the top face of an exemplary portable computer system.
[0029] FIG. 2B is a perspective illustration of one embodiment of a bottom side of the portable computer system of FIG. 2A .
[0030] FIG. 3 is a block diagram of exemplary circuitry of a portable computing system in accordance with one embodiment of the present invention.
[0031] FIG. 4 is a perspective view of the cradle device for connecting the portable computing system to other systems via a communication interface.
[0032] FIG. 5A is a perspective view of the top face of an exemplary portable computer device incorporating an optical user interface, in accordance with one embodiment of the present invention.
[0033] FIG. 5B is a perspective view of the side edge of an exemplary portable computer device incorporating an optical user interface, in accordance with one embodiment of the present invention.
[0034] FIG. 5C is a perspective view of the side edge of an exemplary portable computer device, depicting an array of visually formatted information, including text and highlighted text, on a display screen, and incorporating an optical user interface, in accordance with one embodiment of the present invention.
[0035] FIG. 6A is a concentric top view of an exemplary optical user interface, in accordance with one embodiment of the present invention.
[0036] FIG. 6B is a block diagram of electrical elements of an exemplary optical user interface, in accordance with one embodiment of the present invention.
[0037] FIG. 6C is a block diagram of electrical elements of an exemplary combination optical-electromechanical user interface, in accordance with one embodiment of the present invention.
[0038] FIG. 7A is a schematic diagram of an exemplary combination optical-electromechanical user interface, in accordance with one embodiment of the present invention.
[0039] FIG. 7B is a schematic diagram of en exemplary combination optical-electromechanical user interface, incorporating an exemplary flexible digitizer element, in accordance with one embodiment of the present invention.
[0040] FIG. 8 is a flow chart of steps in an exemplary process for implementing an optical user interface for an electronic device, in accordance with one embodiment of the present invention.
[0041] FIG. 9A is a flow chart of steps in an exemplary process for implementing a variable optical scan rate, in accordance with one embodiment of the present invention.
[0042] FIG. 9B is a flow chart of steps in an exemplary process for implementing a scan rate power usage protocol, in accordance with one embodiment of the present invention.
[0043] FIG. 10 is a flow chart of steps in an exemplary process for changing visually formatted information, in accordance with one embodiment of the present invention.
[0044] The drawings referred to in this description should not be understood as being drawn to scale except if specifically noted.
DETAILED DESCRIPTION OF THE INVENTION
[0045] In the following detailed description of the present invention, an optical sensor based user interface for a handheld device, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be recognized by one skilled in the art that the present invention may be practiced without these specific details or with equivalents thereof. In other instances, well-known methods, procedures, components, and circuits have not been described in detail as not to unnecessarily obscure aspects of the present invention.
Notation and Nomenclature
[0046] Some portions of the detailed descriptions, which follow, are presented in terms of procedures, steps, logic blocks, processing, and other symbolic representations of operations on data bits that can be performed on computer memory. These descriptions and representations are the means used by those skilled in the electronic, computer, and data processing arts to most effectively convey the substance of their work to others skilled in the art. A procedure, computer executed step, logic block, process, etc., is here, and generally, conceived to be a self-consistent sequence of steps or instructions leading to a desired result. The steps are those requiring physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated in a computer system. It has proven convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, or the like.
[0047] It should be borne in mind, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated otherwise as apparent from the following discussions, it is appreciated that throughout the present invention, discussions utilizing terms such as “generating” or “coupling” or “changing” or “scanning” or “sending” or “sensing” or “processing” or “repeating” or “adjusting” or “modifying” or “displaying” or “highlighting” or “scrolling” or “formatting” or “selecting” or “moving” or the like, refer to the action and processes of a computer system or similar electronic computing device, that manipulates and transforms data represented as physical (electronic) quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices.
[0048] The present invention is discussed in one example in the context of a portable computer system, such as a portable computer device, palmtop computer, or personal digital assistant. However, it is appreciated that the present invention can be used with other types of devices that require user interfacing with a computer, e.g., cell phones, remote control devices, portable web browsers, pagers, etc.
[0049] Reference will now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to limit the invention to these embodiments. On the contrary, the invention is intended to cover alternatives, modifications and equivalents, which may be included within the spirit and scope of the invention as defined by the appended claims. Furthermore, in the following detailed description of the present invention, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be obvious to one of ordinary skill in the art that the present invention may be practiced without these specific details.
[0050] Although the optical sensor based user interface of the present invention may be implemented in a variety of different electronic systems such as a pager, a mobile phone, a calculator, a personal digital assistant (PDA), etc., one exemplary embodiment includes the optical sensor based user interface with a portable computing system. It should be understood that the descriptions corresponding to FIGS. 1-4 provide some general information about an exemplary portable computing system.
Exemplary Portable Computer System
[0051] FIG. 1 illustrates a system 50 that may be used in conjunction with an exemplary portable computing device 100 . Specifically, system 50 comprises a host computer system 56 which can either be a desktop unit as shown, or, alternatively, can be a laptop system 58 . Optionally, one or more host computer systems can be used within system 50 . Host computer systems 56 and 58 are shown connected to a communication bus 54 , which in one embodiment can be a serial communication bus, but could be of any of a number of well known communication standards and protocols, e.g., a parallel bus, Ethernet, Local Area Network (LAN), and the like. Optionally, bus 54 can provide communication with the Internet 52 using a number of well known protocols.
[0052] Bus 54 is also coupled to a cradle 60 for receiving and initiating communication with portable computing device 100 . Cradle 60 provides an electrical and mechanical communication interface between bus 54 (and anything coupled to bus 54 ) and the portable computer system 100 for two way communications. Computer system 100 also contains a wireless infrared communication mechanism 64 for sending and receiving information from other devices.
[0053] FIG. 2A is a perspective illustration of the top face 100 a of an exemplary portable computer system 100 . The top face 100 a contains a display screen 105 surrounded by a top cover 110 . A removable stylus 80 is also shown. The display screen 105 is a touch screen able to register contact between the screen and the tip of the stylus 80 . Additionally, the stylus 80 can be fabricated of any material to make contact with the screen 105 . The top face 100 a also contains one or more dedicated and/or programmable buttons 75 for selecting information and causing the computer system 100 to implement functions. The on/off button 95 is also shown.
[0054] FIG. 2A also illustrates a handwriting recognition pad or “digitizer” containing two regions 106 a and 106 b . For example, region 106 a is for the drawing of alpha characters therein for automatic recognition while region 106 b is for the drawing of numeric characters therein for automatic recognition. The stylus 80 is used for stroking a character within one of the regions 106 a and 106 b . The stroke information is then fed to an internal processor for automatic character recognition. Once characters are—recognized, they are typically displayed on the screen 105 for verification and/or modification.
[0055] FIG. 2B is a perspective illustration of one embodiment of a bottom side 100 b of portable computer system 100 . An optional extendible antenna 85 is shown and also a battery storage compartment door 90 is shown. A communication interface 108 is also shown. In one embodiment of the present invention, the communication interface 108 is a serial communication port but could also alternatively be of any of a number of well known communication standards and protocols, e.g., parallel, small computer system interface (SCSI), Ethernet, FireWire (IEEE 1394), Universal Serial Bus (USB), etc.
[0056] FIG. 3 is a block diagram of exemplary circuitry of portable computing system 100 in accordance with one embodiment of the present invention. The computer system 100 includes an address/data bus 99 for communicating information, a central processor 101 coupled with the bus 99 for processing information and instructions. It is appreciated that central processor unit 101 may be a microprocessor or any other type of processor. The computer system 100 also includes data storage features such as a volatile memory 102 (e.g., random access memory, static RAM, dynamic RAM, etc.) coupled with the bus 99 for storing information and instructions for the central processor 101 and a non-volatile memory 103 (e.g., read only memory, programmable ROM, flash memory, EPROM, EEPROM, etc.) coupled with the bus 99 for storing static information and instructions for the processor 101 . Computer system 100 may also include an optional data storage device 104 (e.g., thin profile removable memory) coupled with the bus 99 for storing information and instructions. It should be understood that device 104 may be removable. Furthermore, device 104 may also be a secure digital (SD) card-reader or equivalent removable memory reader.
[0057] Also included in computer system 100 of FIG. 3 is an alphanumeric input device 106 which in one implementation is a handwriting recognition pad (“digitizer”) and may include integrated push buttons in one embodiment Device 106 can communicate information (spatial data and pressure data) and command selections to the central processor 101 . The digitizer 106 records both the (x, y) coordinate value of the current location of the stylus 80 and also simultaneously records the pressure that the stylus 80 exerts on the face of the digitizer pad 106 . The coordinate values (spatial information) and pressure data are then output on separate channels for sampling by the processor 101 . In one implementation, there are roughly 256 different discrete levels of pressure that can be detected by the digitizer 106 . Since the digitizer's channels are sampled serially by the processor 101 , the stroke spatial data are sampled “pseudo” simultaneously with the associated pressure data. The sampled data is then stored in a memory by the processor 101 for later analysis.
[0058] System 100 of FIG. 3 also includes an optional cursor control or directing device 107 coupled to the bus 99 for communicating user input information and command selections to the central processor 101 . In one implementation, device 107 is a touch screen device (also a digitizer) incorporated with screen 105 . Device 107 is capable of registering a position on the screen 105 where the stylus 80 makes contact and the pressure of the contact. The digitizer of 106 or 107 may be implemented using well known devices, for instance, using the ADS-7846 device by Buff-Brown that provides separate channels for spatial stroke information and pressure information.
[0059] Computer system 100 also contains a flat panel display device 105 coupled to the bus 99 for displaying information to the computer user. The display device 105 utilized with the computer system 100 may be a liquid crystal device (LCD), cathode ray tube (CRT), field emission device (FED, also called flat panel CRT), plasma or other display technology suitable for creating graphic images and alphanumeric characters recognizable to the user. In one embodiment, the display 105 is a flat panel multi-mode display capable of both monochrome and color display modes.
[0060] Also included in computer system 100 of FIG. 3 is a signal communication device 108 coupled to bus 99 that may be a serial port (or USB port) for enabling system 100 to communicate with the cradle 60 . As mentioned above, in one embodiment, the communication interface 108 is a serial communication port, but could also alternatively be of any of a number of well known communication standards and protocols, e.g., parallel, SCSI, Ethernet, FireWire (IEEE 1394), USB, etc. In addition to device 108 , wireless communication links can be established between the device 100 and a host computer system (or another portable computer system) using a Bluetooth wireless device 112 , an infrared (IR) device 64 , or a Global System for Messaging (GSM) radio device 114 . System 100 may also include a wireless modem device 114 and/or a wireless radio, e.g., a GSM wireless radio with supporting chip set. The wireless modem device 114 is coupled to communicate with the central processor 101 but may not be directly coupled to port 108 .
[0061] In one implementation, the Mobitex wireless communication system may be used to provide two way communication between computer system 100 and other networked computers and/or the Internet (e.g., via a proxy server). In other embodiments, transmission control protocol (TCP) can be used or Short Message Service (SMS) can be used. System 100 of FIG. 3 may also contain batteries for providing electrical power.
[0062] In one embodiment, Optical User Interface 75 is coupled to Processor 101 by bus 99 . In one embodiment, processor 101 sends an optical signal generation demand signal 770 to optical user interface 75 . In the present embodiment, optical user interface 75 generates an optical signal 555 accordingly. Signal 770 , in one embodiment, controls the optical scan rate of optical user interface 75 . After a user interaction, optical signal 555 is redetected by optical user interface 75 , which generates a corresponding interface signal 771 , which is sent to processor 101 , in one embodiment, with a scan rate power usage signal 772 . In one implementation, optical user interface 75 interacts with display device 105 for control of the exhibition of visually formatted information. In one embodiment, optical user interface 75 interacts with on-screen cursor control 107 and display device 105 for control and positioning of an on-screen cursor. In one embodiment, optical user interface 75 interacts with digitizer 106 . In one embodiment, digitizer 106 is a mechanically flexible and optically transparent pad, enabling both optical and mechanical user interaction via optical user interface 75 , in an optical-electromechanical user interaction enabling implementation. In one embodiment, the optical user interaction is controlled by a program implemented by computer readable and executable instructions distributed to varying degrees in various implementations between processor 101 , RAM 102 , ROM 103 , and storage device 104 .
[0063] FIG. 4 is a perspective illustration of one embodiment of the cradle 60 for receiving the portable computer system 100 . The cradle 60 contains a mechanical and electrical interface 260 for interfacing with communication interlace 108 ( FIG. 2B ) of computer system 100 when system 100 is slid into the cradle 60 in an upright position. Once inserted, button 270 can be pressed to initiate two way communication between portable computer system 100 and other computer systems coupled to communication bus 54 .
Exemplary User Interfaces
Exemplary Optical User Interfaces
[0064] FIG. 5A is a perspective illustration of the top face 100 a of one embodiment of a palmtop computer system 100 , that can be used with the present invention. Optical user interface 75 is depicted as mounted, in one embodiment, in the center of the lower portion of top face 100 a , below screen 105 and digitizer 106 . In one embodiment, optical user interface 75 interacts with digitizer 106 , and may be mounted beneath it. In the present embodiment, digitizer 106 is a mechanically flexible and optically transparent pad, enabling both optical and mechanical user interaction via optical user interface 75 , in an optical-electromechanical user interaction enabling implementation.
[0065] It is appreciated that the position depicted for optical user interface 75 herein is not intended to be limiting. For example, optical user interface 75 may be mounted in any user accessible position on system 100 . Such positions are illustrated, for example only, and not limited to, possible other positions 75 p.
[0066] In FIG. 5B , a perspective illustration of the side edge of exemplary system 100 is depicted. Optical User interface 75 is depicted, for example only, and not limited, in a position low on the upper face 100 a . Lower face 100 b is depicted opposite to upper face 100 a , for perspective.
[0067] In FIG. 5C , a perspective of the top face 100 a of one embodiment of a palmtop computer system 100 , that can be used with the present invention. Optical user interface 75 is depicted as mounted, in one embodiment, in the center of the lower portion of top face 100 a , below screen 105 and digitizer 106 . In one embodiment, optical user interface 75 interacts with digitizer 106 , and may be mounted beneath it.
[0068] Screen 105 displays an exemplary array of visually formatted information 105 d . In the present example, the array of visually formatted information 105 d includes text. It is appreciated that array of visually formatted information 105 d is not limited to text, but may include graphics, combinations of text and graphics, and any other visually formatted information. In the present example, the text constituting array of visually formatted information 105 d is a portion of an imaginary telephone list including names and corresponding telephone numbers, a common and useful portable computer system feature. It is appreciated that the text constituting array of visually formatted information 105 d may include any textual information not to be construed as delimited by the present example. In the present example, the text constituting array of visually formatted information 105 d includes a highlighted portion 105 h . Highlighted portions of text or other forms of visually formatted information may be used to focus a user's attention, to target data for selection, and other purposes. In one embodiment, highlighting can be moved through scrolling. In one embodiment, highlighting and scrolling may be performed by a user interacting with system 100 through manipulation of optical user interface 75 .
[0069] Referring to FIG. 6A , a detailed concentric top view of an exemplary optical user interface 75 , in accordance with one embodiment of the present invention, is described. A transparent covering 75 . 1 covers optical user interface 75 .
[0070] In one embodiment, transparent covering 75 . 1 is flexible and mounted beneath digitizer 106 , which, in the present embodiment, is flexible and transparent, likewise. In one embodiment, transparent covering 75 . 1 forms a part of flexible and transparent digitizer 106 . In one embodiment, flexible and transparent digitizer 106 constitutes transparent covering 75 . 1 . In one embodiment, flexible and transparent digitizer 106 is embedded within transparent cover 75 . 1 (e.g., as depicted in FIG. 7B ). In any of the present embodiments, digitizer 106 is a mechanically flexible and optically transparent pad, enabling both optical and mechanical user interaction via optical user interface 75 , in an optical-electromechanical user interaction enabling implementation.
[0071] Importantly, transparent covering 75 . 1 covers optical user interface 75 , yet allows optical interaction with a user. Further, transparent covering 75 . 1 seals optical user interface 75 , and system 100 about optical user interface 75 . Advantageously, this prevents the incursion of environmental contaminants to seals optical user interface 75 , and system 100 . Optical user interlace enclosure 75 . 2 forms a package about optical user interface 75 optical and electrical components to be described next.
[0072] Optical user interface package foundation 752 mounts an optical source 75 . 4 and an optical sensor 75 . 5 . Further, optical user interlace package foundation 75 . 3 forms an optical portal 75 . 6 , such as an optically transmissive channel with precisely reflective and focusing contours capable of coupling optical source 75 . 4 and an optical sensor 75 . 5 .
[0073] In one embodiment, optical sensor 75 . 5 is a solid state photosensitive electro-optical device which generates an electrical output corresponding to an optical input. In one embodiment, optical sensor 75 . 5 is a quantum photodetector. In one embodiment, optical sensor 75 . 5 is a radiometer. In one embodiment, optical sensor 75 . 5 is a pyroelectric detector. In one embodiment, optical sensor 75 . 5 works photoconductively. In one embodiment, optical sensor 75 . 5 works photovoltaically.
[0074] In one embodiment, optical source 75 . 4 is a light emitting diode (LED). In one embodiment, optical source 75 . 4 is a laser diode (LD). In one embodiment, optical source 75 . 4 is a quantum dot. For simplicity, optical source 75 . 4 will herein be referred to as an exemplary LED 75 . 4 . LED 75 . 4 and optical detector 75 . 5 operate at frequencies which enable their interoperation and coupling. In one embodiment, optical user interface operation is at visible wavelengths. In one embodiment, optical user interface 75 operation is in the infrared. In one implementation, operation of the optical user interlace 75 is in the near infrared.
[0075] Optical portal 75 . 6 couples LED 75 . 4 and optical sensor 75 . 5 in such a way that a user interaction, such as touching transparent covering 75 . 1 , optically modifies the optical coupling between LED 75 . 4 and optical sensor 75 . 5 . Optically coupled scanning between LED 75 . 4 and optical sensor 75 . 5 occurs at a rate controlled by processor 101 ( FIG. 3 ). Optically coupled scanning between LED 75 . 4 and optical sensor 75 . 5 enables detection of commencement, progression, development and modification, and termination of interactions with users.
[0076] In one embodiment, the user touches transparent covering 75 . 1 . The touch may be implemented by the user's thumb or fingertips, for example. In one embodiment, the changes in optical coupling between LED 75 . 4 and optical detector 75 . 5 corresponding to the touch and detected by scanning result in the generation of an interaction signal (interaction signal 771 ; FIG. 6B ). In one embodiment, the optical coupling between LED 75 . 4 and optical detector 75 . 5 corresponding to the touch and detected by scanning can be further, stochastically, and/or continually changed by the user varying the touch to transparent cover 75 . 1 , for example, by movement of the thumb or fingertips touching transparent cover 75 . 1 This correspondingly results in the optical scanning tracking the user transaction and further generating an interaction signal 771 accordingly transmitting the scan-tracking information to processor 101 . Processor 101 may process the information to generate programmatic response. Scan rates may be variable, in one embodiment. In the present embodiment, variable scan rates may implement a scan rate power usage protocol, transmitted by scan rate power usage signals 772 . It is appreciated that the optical user interface 75 may also, in one embodiment, enable further and/or other user interaction by, for example, an electromechanical modality.
[0077] In FIG. 63 , the optical and electrical interrelationship 75 E between elements constituting optical user interface 75 , system bus 99 , and processor 101 are depicted. Optical user interface package foundation 75 . 3 mounts and electrically interconnects LED 75 . 4 and optical sensor 75 . 5 .
[0078] Optical user interface package foundation 75 . 3 mounts LED 75 . 4 and optical sensor 75 . 5 in such a configuration as to delineate optical portal 75 . 6 , optically coupling LED 75 . 4 and optical sensor 75 . 5 . LED 75 . 4 and optical sensor 75 . 5 are optically coupled through optical portal 75 . 6 such that optical signal 655 , emitted by LED 75 . 4 , may be detected by optical sensor 75 . 5 .
[0079] Optical user interface sub-bus 75 . 9 electrically interconnects LED 75 . 4 and optical sensor 75 . 5 , through optical user interface packaging foundation 75 . 3 , to bus 99 , which is electrically interconnected with processor 101 . Signals interflow between these elements as follows.
[0080] Optical signal generation demand signal 770 , generated by processor 101 , flows over busses 99 and 75 . 9 , through optical user interface packaging foundation 75 . 3 interconnection, to LED 75 . 4 , stimulating LED 75 . 4 to emit optical signal 555 accordingly. Processor 101 thus controls signal 555 and corresponding optical scanning via optical portal 75 . 6 . Interface signal 771 , generated by optical. sensor 75 . 5 responsive to detection and conversion of optical signal 555 , flows through optical user interface packaging foundation 75 . 3 interconnection, over busses 75 . 9 and 99 , sequentially, to processor 101 . Processor 101 processes interface signal 771 programmatically.
[0081] Further, in one embodiment, processor 101 controls the optical scan rate employed by optical user interface 75 ( FIG. 6A ) by and according to scan rate power usage signal 772 . Scan rate power usage signal 772 transmits information corresponding to the scan rate power usage from optical user interface 75 to processor 101 , and transmits responsive scan rate control from processor 101 to optical user interface 75 .
[0082] In one embodiment, optical user interface 75 functions as an optical sensor operable to sense movement of an object over a surface thereof, and a processor is responsive to said optical sensor for altering said selected item according to said movement, In one embodiment, optical user interface 75 functions as an optical sensor operable to sense tactile contact of said object with said surface. In one embodiment˜optical user interface 75 functions as an optical sensor operable to sense the speed of said movement of said object. In one embodiment, optical user interface 75 functions as an optical sensor operable to sense the direction of said movement of said object. In the present embodiment, control circuitry coupled to optical user interface 75 is operable to vary a rate at which optical sensor 75 . 5 is scanned in response to detected user activity.
[0083] Processor 101 , in the present embodiment, is responsive to optical sensor 75 . 5 sensing user interactive movement at a first speed to perform a first display update of the array of visually formatted information (e.g., text 105 . d ; FIG. 50 ) Further, processor 101 is responsive to optical sensor 75 . 5 sensing user interactive movement at a second speed to perform a second update of said Information. In the present embodiment, this enables coarse scroll operation, in the first processor response, and a fine scroll operation in the second. The user's finger may establish the optical contact with optical user interface 75 to implement these interactions.
Exemplary Optical-Electromechanical User Interfaces
[0084] With reference to FIG. 6C , the optical and electrical interrelationship 7SEM between elements of an exemplary combination optical-electromechanical user interface 75 m is depicted, in accordance with one embodiment of the present invention. Optical user interface package foundation 75 . 3 mounts LED 75 . 4 and optical sensor 75 . 5 in such a configuration as to delineate optical portal 75 . 6 , optically coupling LED 75 . 4 and optical sensor 75 . 5 . LED 75 . 4 and optical sensor 75 . 5 are optically coupled through optical portal 75 . 6 such that optical signal 555 , emitted by LED 75 . 4 , may be detected by optical sensor 75 . 5 . Optical user interface sub-bus 75 . 9 electrically interconnects LED 75 . 4 and optical sensor 75 . 5 , through optical user interface packaging foundation 75 . 3 , to user interface mid-bus 859 , which is electrically interconnected through bus 99 with processor 101 .
[0085] User interface opto-electromechanical package foundation 803 mounts optical user interface module 75 , and contains an electromechanical user interface enabling device such as a switch or dial (e.g., switch 804 , FIGS. 7A and 7B ). User interface electromechanical package foundation 803 electrically interconnects the electromechanical user interface (e.g., switch 804 , FIGS. 7A and 7B ) contained within it via electromechanical interface sub-bus 809 b to user interface mid-bus 859 , which is electrically interconnected through bus 99 with processor 101 , and transmits electromechanical interface signal 866 thereon.
[0086] With reference to FIG. 7A , an exemplary combination optical-electromechanical user interface enables several modalities of user interaction, in accordance with one embodiment of the present invention. An electronic device, in the present illustration, exemplary portable computer system 100 , has a top face 100 a and a bottom face 100 b . Embedded within and sealing top face 100 a is transparent cover 75 . 1 .
[0087] Transparent cover 75 . 1 covers optical user interface enclosure 75 . 2 which contains optical user interface package foundation 75 . 3 mount in 9 LED 75 . 4 and optical sensor 75 . 5 ( FIG. 6 ). Further, optical user interface package foundation 75 . 3 forms an optical portal 75 . 6 ( FIG. 6C ), such as an optically transmissive channel with precisely reflective and focusing contours capable of coupling optical source 75 . 4 ( FIG. 6C ) and an optical sensor 75 . 5 ( FIG. 6C ). Optical user interface enclosure 75 . 2 forms a package about optical user interface 75 optical and electrical components ( FIG. 6C ). Optical user interface 75 ( FIGS. 6B and 6C ) generates an optical interface signal 711 ( FIG. 6B ).
[0088] Mounting optical user interface (e.g., optical user interface 75 ; FIG. 6C ) components 75 . 1 , 75 . 2 , and 75 . 3 , opto-electromechanical package foundation 803 also houses electromechanical user interface enabling components including, in the present embodiment, a switch assembly 804 .
[0089] Switch assembly 804 contains a lower, foundational and non-moving base 802 b , fixedly mounted on the upper (e.g., inner) surface of base 110 b (e.g., internal to exemplary computer 100 ). Base 802 b mounts a set of fixed electrical contacts 801 b . An upper plug 802 a mounts movable electrical contacts 801 a , is spring supported and guided by spring assembly 823 . Upper plug 802 a and contacts 801 a move up and down in switch assembly 804 in such a way as to respond to the interaction of a user, for example, pressing down on transparent cover 75 . 1 , and make and break contact between movable contacts 801 a and fixed contacts 801 b accordingly.
[0090] Upon contact by a sufficiently forcible user interaction, movable contacts 801 a will make and wipe sufficiently on and over fixed contacts 801 b to ensure a correspondingly sufficient electrical contact. The making and breaking of movable contacts 801 a and fixed contacts 801 b in response to a mechanical user interaction generate an electromechanical user interface signal 866 ( FIG. 6C ).
[0091] Optical user interface signal 771 flows on optical user interface sub-bus 75 . 9 ( FIG. 6B ). Electromechanical user interface signal 866 ( FIG. 6C ) flows on electromechanical sub-bus 809 b . Sub-busses 75 . 9 and 809 b are electrically interconnected with user interface mid-bus 859 . User interface mid-bus 859 is electrically interconnected with bus 99 ( FIGS. 3 , 6 C), enabling optical and electromechanical interface signals 771 and 866 , respectively, to be sent to processor 101 ( FIGS. 3 and 6C ), and control signals to flow from processor 101 back to the user interfaces 76 and 75 m ( FIG. 6C ).
[0092] Referring now to FIG. 7B , one embodiment of the present invention is depicted, wherein digitizer 106 is also flexible and transparent. In all other respects, the elements depicted in FIG. 7B are identical in form and function with those depicted in FIG. 7A . In the present embodiment, digitizer 106 is integrated with transparent cover 75 . 1 . In the present embodiment, the transparency of digitizer 106 , and its proximity to optical user interface package foundation 75 . 3 , enables an interaction with a user for exemplary system 100 via the optical user interface (e.g., optical user interface 75 ; FIG. 6C ). Further, the flexibility of digitizer 106 , and its proximity to and mechanical integration with opto-electromechanical package foundation 803 , enables an interaction with a user for exemplary system 100 via the electromechanical user interface (e.g., electromechanical user interface 75 m ; FIG. 6C ).
[0093] In the present embodiment, flexible and transparent digitizer 106 is embedded within transparent cover 75 . 1 (e.g., as depicted in FIG. 7B ). In one embodiment, transparent covering 75 . 1 is flexible and mounted beneath digitizer 106 , which, in the present embodiment, is flexible and transparent, likewise. In one embodiment, transparent covering 75 . 1 forms a part of flexible and transparent digitizer 106 . In one embodiment, flexible and transparent digitizer 106 constitutes transparent covering 75 . 1 . In any of these embodiments, digitizer 106 is a mechanically flexible and optically transparent pad, enabling both optical and mechanical user interaction via optical user interface 75 ( FIG. 6C ) and electromechanical user interface 75 m ( FIG. 6C ), in an optical-electromechanical user interaction enabling implementation. Digitizer sub-bus 106 . 1 is electrically interconnected with bus 99 , interconnecting digitizer 106 with processor 101 ( FIG. 3 ).
Exemplary Processes
[0094] FIGS. 8 , 9 A, 9 B, and 10 are flowcharts of the steps performed in processes 800 , 900 A, 900 B, and 1000 , respectively, each individually in accordance with single, separate individual embodiments of the present invention, as discussed separately below. Flowcharted processes 800 , 900 A, 900 B, and 1000 each include a single, separate, individual process of the present invention which, in each embodiment, are carried out by processors and electrical components under the control of computer readable and computer executable instructions. The computer readable and computer executable instructions reside, for example, in data storage features such as within processor 101 , computer usable volatile memory 102 , computer usable non-volatile memory 103 , and/or data storage device 104 , all of FIG. 3 . However, the computer readable and computer executable instructions may reside In any type of computer readable medium. Although specific steps are disclosed in each of flowcharts 800 , 900 A, 900 B, and 1000 , such steps are exemplary. That is, the present invention is well suited to performing various other steps or variations of the steps recited in FIGS. 8 , 9 A, 9 B, and 10 . Within these present embodiments, it should be appreciated that the steps of flowcharts 800 , 900 A, 900 B, and 1000 may be performed by software or hardware or any combination of software and hardware.
Exemplary Process for User Interaction
[0095] Referring to FIG. 8 , the steps in a process 800 enable the interaction of a user with a system (e.g., exemplary system 100 ; FIGS. 1 , 3 , 5 A, 5 B, 7 A, and 7 B)-using an optical user interface (e.g., 75 ; FIGS. 2A , 3 , 5 A, 5 B, 6 A, 6 B, 6 C), in accordance with one embodiment of the present invention. Beginning with step 801 , an optical signal (e.g., optical signal 555 ; FIGS. 6B and 6C ) is demanded by a processor (e.g., processor 101 ; FIGS. 3 , 6 B, and 6 C). The demand may be by a demand signal (e.g., 770 ; FIG. 6B ).
[0096] In step 802 , an optical signal (e.g., optical signal 555 ; FIGS. 6B and 6C ) is generated responsive to the demand (step 801 ). The optical signal is generated by an optical source (e.g., optical source 75 . 4 ; FIGS. 6A , 6 B, and 6 C), which in one embodiment, is an LED.
[0097] In step 803 , the optical signal is coupled from the optical source into an optical portal (e.g., optical portal 75 . 6 ; FIGS. 6A , 6 B, and 6 C).
[0098] The optical portal is scanned; step 804 . Scanning 1 in one embodiment, may be performed by an optical sensor (e.g., optical detector 75 . 5 ; FIGS. 6A , 6 B, and 6 C).
[0099] Scanning the optical portal (step 804 ) enables the detection of a user interaction; step 805 . If no user interaction is detected, process 800 loops back to demanding an optical signal (step 801 ), and the process repeats itself.
[0100] If, however, a user interaction is detected in step 805 , the optical coupling characteristics of the optical portal are changed by the interaction of the user. This results in a corresponding change in the optical coupling characteristics of the optical portal coupling the source and detector; step 807 .
[0101] Any change in optical coupling results in the generation of an interface signal in step 808 .
[0102] Interface signals are sent to a processor (e.g., processor 101 ; FIGS. 3 , 6 B, and 6 C); step 809 . The interface signals may be sent via an interconnecting bus (e.g., bus 99 ; FIGS. 3 , 6 B, and 6 C).
[0103] In step 810 , the processor processes the interface signal as information, and process 800 loops back to the step of demanding an optical signal (step 801 ).
Exemplary Scan Rate Adjustment Process
[0104] Referring to FIG. 9A , the steps in a process 900 A are depicted wherein the scanning rate of an optical user interface is automatically adjusted, in accordance with one embodiment of the present invention. Beginning with step 901 , the optical user interface (OUI) (e.g., OUI 75 ; FIGS. 3 , 6 A, 6 B, and 6 C) under the control of a processor (e.g., processor 101 ; FIGS. 3 , 6 B, and 6 C), scans at a first, relatively slow rate.
[0105] If no interaction with a user is detected in step 902 , process 900 A continues the scanning at the first rate.
[0106] If however, an interaction with a user is detected in step 902 , the activation of a user interaction is sensed; step 903 .
[0107] Upon detecting activation of a user interaction (step 903 ), the scan rate is increased accordingly to an initial, relatively higher rate; step 904 .
[0108] In step 905 , the speed with which the user interaction is occurring and/or varying (for example, the relative speed and any speed variation with which the user's thumb passes, rubs, or flicks over the transparent cover of the optical portal, e.g., cover 75 . 1 and portal 75 . 6 , respectively; FIGS. 6A , 6 B, and 6 C) is detected. If no variation in the speed with which the user interaction is occurring is detected, process 900 A loops back to step 904 , and continues to scan at the initial second rate.
[0109] If, however, a variation in the speed with which the user interaction is occurring is detected in step 905 , the scan rate is adjusted accordingly; step 906 . Further, the speed with which the user interaction is occurring and/or varying is continually monitored, process 900 A looping back to step 905 .
[0110] This continues as long as no interruption in the user interaction is detected in step 907 . If an interruption in the user interaction is detected in step 907 , process 900 A loops back to step 901 , with scanning resumed at the relatively slow first scan rate. In one embodiment, process 900 A enables implementation of a scan rate power usage protocol.
Exemplary Scan Rate Power Usage Information Process
[0111] In one embodiment, a process 900 B enables a processor (e.g., processor 101 ; FIGS. 3 , 6 B, and 6 C) to receive information regarding power usage by optical scanning processes (e.g., process 900 A; FIG. 9A ).
[0112] Process 900 B begins with step 910 , wherein a fixed power usage signal is generated corresponding to a first scan rate (e.g., a relatively low initial scan rate, such as that scan rate generated instep 901 ; FIG. 9A ).
[0113] Power usage signals generated in step 910 is sent to a processor; step 940 .
[0114] In step 920 , the scan rate is monitored, if scanning continues at the first scan rate (e.g., no user interaction is detected, as for example in step 902 ; FIG. 9A ), the corresponding power usage signal continues to be generated, process 900 B looping back to step 910 .
[0115] If scanning at a second rate is detected in step 920 , a variable power usage signal corresponding to the second scan rate and its changes is generated; step 930 .
[0116] Power usage signals generated in step 920 is sent to a processor; step 940 .
[0117] Power usage signals and corresponding control signals (e.g., signals 772 ; FIG. 6B ) enable implementation of a scan rate power usage protocol.
Exemplary Process for Display Control
[0118] With reference to FIG. 10 , a process 1000 enables the control of visually formatted information displayed on a screen (e.g., display screen 105 ; FIGS. 2A , 3 , and 5 A). Beginning with step 1010 , a user manipulates an optical user interface (e.g., OUI 75 ; FIGS. 3 , 5 A, 53 , 6 A, 6 B, and 6 C) according to the user's intent to vary visibly formatted information on the display screen.
[0119] The optical characteristics of the optical user interface are changed accordingly; step 1020 .
[0120] Resultantly, a display change signal is generated; step 1030 . Generating a display change signal may be a combination and interaction between integrated activities conducted by different system elements.
[0121] Upon changing optical characteristics in the optical user interface (step 1020 ), a corresponding interface signal (e.g., signal 771 ; FIG. 6B ) is generated and sent to the processor (e.g., processor 101 ; FIGS. 3 , 6 B, and 6 C). The processor programmatically responds to the interface signal by generating a responsive display control signal, which is transmitted to the display device to change the array of visibly formatted information thereon accordingly; step 1040 . The programmatic response may be controlled by the processor under the direction of software or data stored, to varying degrees, in the processor itself, in memory, an and/or in a data storage device (e.g., RAM 102 , ROM 103 , and/or storage 104 , respectively; FIG. 3 ). If a cursor and/or scrolling, for example (discussed below in steps 1060 through 1075 ), is included in the array of visually formatted information displayed on the screen, an cursor controller (e.g., cursor control 107 ; FIG. 3 ) may also be involved.
[0122] In step 1050 , it is determined if the user intends to change the highlighting of any portion of the array of visually formatted information, by which portions of the array may be designated or selected for change of selection of displayed information, or a scrolling function. If so, the portion to be highlighted is selected by optical user interfacing; step 1051 .
[0123] The highlighting (e.g., the highlighted region of the array of visually formatted information on the display), or the highlighting itself, is moved; step 1052 . At this point, process 1000 may be complete.
[0124] If no highlighting was determined for selection (step 1050 ), it is determined if the user intends to change the positioning of a cursor appearing within the array of visually formatted information, by which the attention and action of the user may be directed and/or focused; step 1060 . If so, the position for placement of the cursor is selected by optical user interfacing instep 1061 .
[0125] The cursor is thus moved to the designated location within the array of visually formatted information; step 1062 . At this point, process 1000 may be complete.
[0126] If no cursor positioning was selected (step 1060 ), it is determined in step 1070 if the visually formatted information array is to be scrolled. If not, process 1000 may be complete.
[0127] If scrolling is designated (step 1060 ), scrolling is initiated and controlled by optical user interfacing; step 1075 . At this point, process 1000 is complete.
[0128] An embodiment of the present invention, an optical sensor based user interface for a handheld device is thus described. While the present invention has been described in particular embodiments, it should be appreciated that the present invention should not be construed as limited by such embodiments, but rather construed according to the below claims. | An apparatus and method are described herein, which simultaneously promotes a positive computing experience for users of portable computer systems and increases overall durability and longevity thereof. In one embodiment, an optical apparatus enhances the user computing experience, in one embodiment by simplifying operation, and is much more durable and long-lasting than mechanical switch and dial type devices it may replace. In one embodiment, the present invention is directed to an apparatus, which enables efficient portable computer device function, field, and data selection, gaming, input, interconnection, and other switching-related functions, simplifying operation and enhancing versatility thereof, yet without exposing the portable computer interior to any degree to incursion of environmental contamination. In one embodiment, an optical apparatus obviates openings in a portable computer package which would otherwise be required. In one embodiment, the apparatus, capable of sensing manipulation and directed by software, has a light source and corresponding light sensor. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a processing apparatus for an image pickup element.
[0003] 2. Related Background Art
[0004] A conventional method for driving an area type solid image pickup element is achieved in the manner illustrated in FIG. 6. An area image pickup element 101 is supplied with horizontal transfer pulses from a timing generator 909 and vertical transfer pulses via a vertical driver 105 . An image picked-up signal is read out from the area image pickup element 101 and then supplied to an analog front end 103 . The analog front end 103 sequentially performs correlated double sampling, gain adjustment and A/D conversion and supplies the processed result to a digital signal processor (DSP) 905 . The digital signal processor 905 generates an image signal constituted of a luminance signal and color difference signals, from the supplied digital signals, and outputs the generated signal to an external via a terminal 107 . The digital signal processor 905 operates in response to a clock generated by the timing generator 909 , and generates HD/VD pulses of NTSC or PAL to return them to the timing generator 909 . The timing generator 909 establishes frame synchronization by generating various read pulses for the area image pickup element 101 in accordance with the HD/VD pulses.
[0005] A conventional timing generator is designed only for each area image pickup element 101 and therefore is not compatible with other types of area image pickup elements. The timing generator is also required to be designed so as to handle not only a moving image taking mode but also a still image taking mode and a monitoring mode, in case that the image pickup element has the latter two modes in addition to the moving image taking mode. If there is any change in combination of image taking modes, it is necessary to redesign a timing generator, resulting in a high cost.
SUMMARY OF THE INVENTION
[0006] An object of the invention is to provide a processing apparatus capable of flexibly changing the driving timings for an image pickup element.
[0007] In order to attain this object, according to an embodiment of the present invention, a processing apparatus comprises a drive pulse generator circuit for generating a drive pulse to be supplied to an image pickup element and a wave form data supply circuit for supplying wave form setting data for generating the drive pulse to the drive pulse generator circuit at each horizontal line, wherein the wave form setting data includes a wave form setting data to be set at each horizontal line and wave form setting data sharing a setting area.
[0008] Other objects and features of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] [0009]FIG. 1 is a diagram illustrating an example of a driving method and system to which the present invention is applied.
[0010] [0010]FIG. 2 is a diagram showing the details of a timing generator unit 111 .
[0011] [0011]FIG. 3 is a diagram illustrating how a wave form generator circuit 225 generates a wave form.
[0012] [0012]FIG. 4 is a diagram illustrating CMD data.
[0013] [0013]FIG. 5 is a diagram showing the structure of circuits for generating a wave form, the circuits being built in a DSP 109 .
[0014] [0014]FIG. 6 is a diagram illustrating the structure of a conventional processing apparatus;
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] [0015]FIG. 1 is a diagram which best shows the features of this invention. In FIG. 1, reference numeral 100 denotes an optical lens. An area image pickup element 101 is supplied, as will be later detailed, with horizontal transfer pulses H 1 and H 2 and a reset gate pulse RG from a timing generator unit 111 and with vertical transfer pulses V 1 , V 2 , V 3 and V 4 from the timing generator unit 111 via a vertical driver 105 . A signal picked up by the area image pickup element 101 are supplied to an analog front end 103 to be subjected to correlated double sampling (CDS), gain adjustment (AGC) and A/D conversion, in a manner similar to conventional techniques. This digitalized image signal is supplied to a digital signal processor (DSP) 109 . Similar to a conventional manner, DSP 109 generates an image signal constituted of a luminance signal and color difference signals and outputs it to an external via a terminal 107 . The DSP 109 shares a roll of generating various wave forms together with the timing generator unit 111 .
[0016] The details of the timing generator unit 111 are shown in FIG. 2. Reference numeral 201 denotes an input terminal at which a command (hereinafter abbreviated to CMD) supplied from the DSP 109 is received. Reference numeral 203 denotes an input terminal at which a horizontal timing signal (hereinafter abbreviated to HD) supplied from the DSP 109 is received. Reference numerals 205 and 226 denote a wave form generation block. Reference numeral 207 denotes a horizontal counter, reference numeral 209 denotes a decoder for decoding an output of the horizontal counter 207 , reference numeral 221 denotes a decoder for decoding the highest level area of a CMD input, and reference numeral 222 denotes AND circuits. The wave form generation block 205 is constituted of registers 211 and 213 and a wave form generation circuit 215 . Similarly, the wave form generation block 226 is constituted of registers 223 and 224 and a wave form generation circuit 225 . The wave form generation block 205 generates the wave form of a vertical transfer pulse VX 1 . Similar blocks having the same internal structure as that of the block 226 are also provided for generating the wave forms of remaining four-phase vertical transfer pulses VX 2 , VX 3 and VX 4 , sensor gate pulses SG 1 and SG 3 to be applied to the vertical transfer pulse, a PBLK pulse designating a pre-blanking portion (a mask-timing portion for blocking the horizontal transfer pulse near in the area where the vertical transfer pulse is generated), an OB pulse designating an optical black portion and a DM pulse designating a dummy pixel. These signal wave forms differ greatly depending upon an operation mode such as blanking and normal transferring. The wave form setting data is required as CMD at each horizontal period.
[0017] The wave form generation block 226 generates the wave form of the horizontal transfer pulse H 1 . Similar blocks having the same internal structure as that of the wave form generation block 226 are also provided for generating the wave forms of a remaining two-phase horizontal transfer pulse H 2 , correlated double sampling pulses SHP and SHD, a reset gate pulse RG for supplying a reference voltage of the image pickup element 101 , and an ADCLK to be used for A/D conversion at the analog front end AFE 103 . Since the internal structure of each of these blocks is the same as that of the wave form generation block 226 , the description thereof is omitted. These signal wave forms are maintained constant irrespective of the operation mode such as blanking and normal transferring.
[0018] [0018]FIG. 4 is a diagram showing CMD data which is output starting at the trailing edge of the HD signal. Wave form setting data 401 to 409 are sequentially supplied in the order shown in FIG. 4. Reference numeral 401 denotes an area where flags 411 to 416 to be described later are selectively output at each horizontal synchronization. Reference numerals 402 to 410 denote data fields where signals XV 1 , XV 2 , XV 3 , XV 4 , SG 1 , SG 3 , PBLK, OB and DM are set respectively. The decoder 209 decodes the data in the data fields 401 to 409 . Reference numerals 411 to 416 denote the flags “0” to “5” which are set to the upper (left) area and indicate the types of wave forms to be set. The flags “0” to “5” are used for H 1 , H 2 , SHP, SHD, RG and ADCLK, respectively. The decoder 221 decodes this upper area.
[0019] Referring to FIG. 4, the horizontal counter 207 is reset at the trailing edge of the HD signal input to the terminal 203 , and counts up in response to each clock DCLK. The value of the horizontal counter are supplied to the decoder 209 , wave form generation block 205 and AND circuits 222 .
[0020] As to the area 401 , the decoder 209 outputs DECO having a value “1” to the AND circuits 222 to release the masking of DECA to DECB. For example, when the flag 411 is set to the area 401 , the decoder 221 outputs DECA so that the CMD data (H 1 _set) is written in the register 223 via the AND circuit 222 . In response to the next HD trailing edge, the value in the register 223 is written in the register 224 to make the wave form generation circuit 225 generate the H 1 waveform.
[0021] The operation of generating each wave form is illustrated in FIG. 3. Reference numeral 302 denotes a trailing edge of the horizontal blanking signal. In response to this trailing edge, the wave form generation circuit 225 outputs an initial value. In the present embodiment, “1” is set to the initial value. Reference numeral 305 denotes a change point 1 upon which the contents of CMD[A] are reflected, and the wave form is inverted at this point 1 . Similarly, reference numeral 306 denotes a change point 2 upon which the contents of CMD[A] are reflected, and the wave form is inverted again at this point 2 . By repeating such an operation a plurality of times, a necessary wave form can be generated. If the number of change points is set to 0 or a greater value, a wave form not changing during the horizontal period can obviously be generated. Two change points per one horizontal period are sufficient for the mask pulse of the sensor gate pulse or horizontal transfer pulse.
[0022] The wave form generation circuit 225 is supplied with the count value from the horizontal counter 207 and with the initial value of a waveform to be described later and several change points (in this case, the change point 1 and change point 2 ) from the register 224 . When the count value of the horizontal counter 207 takes “0”, the wave form generation circuit 225 outputs the initial value. When the values of the change point 1 and horizontal counter become equal, the wave form generation circuit 225 inverts its output value. Similarly, when the values of the change point 2 and horizontal counter become equal, the wave form generation circuit 225 inverts its output value again. In this case, since the output is assumed to be a binary value, the same value is output when the level is inverted by even times.
[0023] For the vertical pulse VX 1 , i.e., for the area 402 , the decoder 209 outputs DEC 1 having a value “1” to the wave form generation block 205 . Similar to the wave form generation block 226 , the wave form generation block 205 writes the CMD data in the register 211 and writes it in the register 213 in response to the trailing edge of HD to make the wave form generation circuit 215 generate the waveform of VX 1 . The change points are prepared as many as necessary because the wave forms of vertical pulses (VX 1 , VX 2 , VX 3 and VX 4 ) and the like are complicated.
[0024] [0024]FIG. 5 shows the structure of wave form generating circuits built in DSP 109 . Reference numeral 501 denotes an input terminal to which the clock DCLK is input, reference numeral 503 denotes a vertical counter, reference numeral 505 denotes a horizontal counter, reference numeral 509 denotes a switch, reference numeral 511 denotes a command output terminal, reference numeral 513 denotes an HD output terminal, reference numeral 515 denotes an address generation unit, reference numeral 517 denotes a microcomputer bus, reference numerals 519 , 521 and 531 denote memories, reference numeral 532 denotes a switch and reference numeral 533 denotes a CPU. The vertical counter 503 and horizontal counter 505 are used for generating timings at which a two-dimensional image is read out from the area image pickup element 101 . The count values of these two counters are supplied to the address generation unit 515 . In accordance with the count values of the vertical and horizontal counters, the address generation unit 515 generates addresses and supplies them to the memories 519 , 521 and 531 . An output of the vertical counter 503 is inverted at each frame and applied to the switch 509 to alternately switch among the memories 519 and 521 . The switch 509 is connected to one input terminal of the switch 532 , and the other input terminal of the switch 532 is connected to an output terminal of the memory 531 . In accordance with the count value of the horizontal counter 505 , an output of the memory 531 is selected for the area 401 (FIG. 4) and the output of the switch 509 is selected for the other areas. In this manner, the CMD data is output to the CMD output terminal 511 .
[0025] The horizontal counter 405 also generates the HD signal and outputs it to the terminal 513 .
[0026] As shown in FIG. 3, at the terminals 511 and 513 , CMD is output at the trailing edge of the horizontal blanking signal, and this output operation is terminated after the necessary number of CMDs is output. By terminating CMD near in the horizontal blanking period, it is possible to suppress minimally CMD data from leaking into an output of the area image pickup element to become noise sources.
[0027] With this arrangement described above, data of wave form data to be generated in the next frame is written in advance in one of the memories 519 and 521 presently not selected by the switch 509 . At the next frame, the switch 509 is turned to the side of the thus-written wave form data. Data may be written in the memory 531 during the initial sequence such as a power-on or in each image pickup mode.
[0028] In the manner described above, the initial value for each of all wave forms to be generated during the horizontal period and the wave form data for predetermined number of change points for each waveform are read out and supplied to the wave form generation block 205 via the output terminal 511 and input terminal 201 .
[0029] As described so far, the wave form data to be generated is loaded in the register 211 during the previous horizontal period. The memories of large scale is provided on the side of DSP 109 which is driven at a low voltage in a later process of the operation sequence, and only the horizontal counter is provided on the side of the timing generator unit 111 for generating drive pulses of the area image pickup element. It is therefore possible to flexibly deal with change of the area image pickup element, resulting in a reduction in development cost of a DSP and a timing generator unit.
[0030] Data for the next frame is written in the memories 519 , 521 and 531 , and during the next horizontal period, the next wave form data is written in advance in the timing generator unit 111 via DSP 109 . With this arrangement, a versatile timing generator can be configured irrespective of the type of an area image pickup element. Even if a moving image pickup mode, a still image pickup mode and a monitor mode are all used, any one of these modes can be realized easily only by sequentially changing data to be written in the memories 519 , 521 and 531 .
[0031] For a versatile timing generator, a large amount of setting data is required in order to flexibly deal with a change in mode or timing, and it may happen in the worst case that the data may not be written within the horizontal blanking but may require the effective image area to be written, so that the image quality is degraded. According to the invention, however, wave form setting data which changes in the unit of line and data which does not change in the unit of line are used separately. The latter data shares the area of wave form setting values, so that it is possible to reduce the number of wave form setting data to be transferred in the unit of horizontal synchronization (line), thereby achieving to send necessary wave form setting values within a short horizontal blanking period. The invention is particularly effective for a versatile timing generator which requires to send a large number of wave form setting values.
[0032] Many widely different embodiments of the present invention may be constructed without departing from the spirit and scope of the present invention. It should be understood that the present invention is not limited to the specific embodiments described in the specification, except as defined in the appended claims. | A processing apparatus having a drive pulse generator circuit for generating a drive pulse to be supplied to an image pickup element, and a wave form data supply circuit for supplying wave form setting data for generating the drive pulse to the drive pulse generator circuit at each horizontal line, wherein the wave form setting data includes a wave form setting data to be set at each horizontal line and wave form setting data sharing a setting area. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation-in-part application of U.S. application Ser. No. 08/535,220 filed Nov. 16, 1995 (now abandoned) from PCT application No. PCT/SE94/00398 (published as WO 94/26562) filed on May 3, 1994, claiming priority from SE 9301730-9 filed May 19, 1993; and PCT application No. PCT/SE94/00916 (published as WO 96/10496) filed Sep. 30, 1994.
FIELD OF THE INVENTION
The present invention relates to an apparatus for inflating an empty flexible container, such as an airbag, incorporated in the passenger compartment of an automobile. The container is inflated with gas immediately, or substantially so, upon application of significant retardation or deceleration forces to the automobile. The container prevents or significantly reduces injury, otherwise suffered by a person seated in the vehicle in the event of a collision.
BACKGROUND OF THE INVENTION
Cars are typically equipped with airbags as an alternative or supplement to safety belts. In the event of a collision, the airbags are inflated extremely quickly in front of the driver or passengers, to protect the driver or passengers from injury that they might otherwise suffer if thrown forwards against the steering wheel or the instrument panel of the vehicle.
At present, automotive vehicles are not fitted with airbags for backseat passengers. One reason for this is that very large bags would be needed for protection of those in the rear vehicle seat. There are numerous problems associated with inflating such large airbags, such as achieving sufficient inflation within the requisite time period.
In the event of a head-on collision, or any type of collision in which the vehicle is brought to an abrupt halt, it must be possible to inflate the bag with gas before the driver or passengers, who continue to move at the original speed of the vehicle, strike the back of the front seat or are thrown against the steering wheel and/or the instrument panel.
In order to obtain effective protection, it is estimated that the airbag or like cushion must be inflated within one-hundredth of a second. Assuming that a car is traveling at a speed of 110 km/hour when a collision occurs, a person seated in the car will travel through a distance of about 0.3 meter in relation to the ground within this period of time. Since the actual body of the vehicle will not stop immediately, by virtue of the front of the vehicle buckling inwards through a distance of one or more decimeters, the driver of the vehicle or passengers carried therein will move forwards through a distance of from about one to two decimeters relative to the vehicle body in the space of 0.01 seconds. Accordingly, the cushion or bag must inflate within this time period and therewith prevent the driver of passengers being thrown onto the driving wheel, the instrument panel, or the backrest of the front seat.
When a gas expands in the absence of an exchange of energy (isoenthalpic expansion), as during inflation of the bags described herein, the temperature will normally fall in accordance with the effect. In the case of air or nitrogen, which is permitted to expand from 400 to 2 bars, the temperature of the gas will decrease by about 70° to 100° C. As will be appreciated, the significantly reduced temperature of the gas severely decreases the volume of the bag or cushion upon inflation. When the gas is stored in high pressure containers, as in the case with airbags, it is necessary to either supply corresponding heat to the gas to obtain the volume that would be obtained at room temperature, or the pressure container must be filled with about 30% more gas to compensate for this effect.
In addition to temperature reduction, it must be remembered that air, nitrogen and other gases have a compressibility factor of about 1.2 at 400 bars, which must also be taken into account when dimensioning the bag or flexible container. Such a compressibility factor requires that the pressure or the volume must be increased to a corresponding degree in comparison with what would have been the case for an ideal gas.
Another problem encountered with the use of heavy gases for airbag inflation is that the outflow velocity of the gas is relatively low, since the velocity is a function of both molecular weight and temperature.
DE-A-4 231 356 discloses an apparatus comprising two gas receptacles and a combustion chamber provided upstream of an inflatable flexible container. The apparatus includes an ignition means for initiating the combustion of the gases from the receptacles in the combustion chamber. The combustion chamber is generally separated from the flexible container by means of an end wall in the form of a burst disk. The disk bursts when the pressure in the combustion chamber reaches a predetermined level. In another embodiment, the burst disk is replaced by a flow control orifice that controls the gas flow rate to the inflatable container and the pressure in the combustion chamber. Thus, no free flow of gas from the receptacles to the inflatable container is possible.
DE-A-2 501 602 discloses another type of apparatus for filling a vehicle mounted empty flexible container with gas when the container is subjected to powerful retardation forces. The apparatus includes a pressure receptacle which is filled with pressurized gas to be expanded for filling the flexible container upon retardation, and an ignition chamber comprising a medium to be ignited for raising the temperature of the expanding gas during filling of the flexible container.
Although satisfactory in some respects, known airbag inflation systems exhibit many of the previously noted disadvantages. Thus, there is a need for an inflation system that overcomes many if not all of these drawbacks, and that can be readily and economically incorporated into a vehicle.
SUMMARY OF THE INVENTION
The present invention provides an apparatus for filling a vehicle mounted flexible container with gas essentially instantaneously when the container is subjected to powerful retardation forces. The gas-filled container functions as a force absorbing cushion which protects occupants in the vehicle against injuries. The apparatus includes a first pressure receptacle which is filled with oxygen and an inert gas under high pressure, and a second pressure receptacle which is filled with hydrogen and an inert gas under high pressure. The inert gas in the first pressure receptacle is helium, argon and/or nitrogen. The inert gas in the second pressure receptacle is the same or a different mixture of helium, argon, and/or nitrogen. The apparatus includes a closure device in association with each of the first and second receptacles and respective connection conduits that join the receptacles to the flexible container. The apparatus may further include a container-holding device or mixing chamber, a retardation meter, and an ignition device.
Moreover, the present invention provides a method of filling an empty flexible container with gas essentially instantaneously when subjected to powerful retardation forces, wherein the gas-filled container serves as a force absorbing cushion for protection against injury. The method comprises the use of an apparatus which includes two pressure receptacles which are sealed with the aid of a closure means and which contain gas under high pressure. The apparatus further includes a first conduit which extends from one pressure receptacle to the flexible container or to a chamber providing access thereto, a second conduit which extends from the other pressure receptacle to the container or chamber, and an ignition device. One pressure receptacle contains oxygen and an inert gas and the other pressure receptacle contains hydrogen and an inert gas. The inert gas in one of the pressure receptacles is helium, argon and/or nitrogen. The inert gas in the other pressure receptacle is the same or a different mixture of helium, argon, and/or nitrogen. The method further comprises passing the gases from the receptacles into the flexible container, and igniting the resulting gas mixture.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 schematically illustrates a preferred embodiment inflation system comprising two gas containers that are connected to a conduit in connection with an empty gas bag;
FIG. 2 schematically illustrates another preferred embodiment inflation system comprising two gas containers connected to a conduit which in turn is connected to a partially filled gas cushion;
FIG. 3 schematically illustrates another preferred embodiment inflation system in which each of the two gas containers is connected to the gas cushion by a separate conduit;
FIG. 4 is a cross-section of a wall of a preferred embodiment gas bag;
FIG. 5 schematically illustrates yet another preferred embodiment inflation system comprising two gas containers connected to a gas cushion via a sliding duct assembly; and
FIG. 6 illustrates the system of FIG. 5 upon activation and inflation of the gas cushion.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates a preferred embodiment inflation apparatus 15 comprising a main conduit 5 extending from an empty gas bag 10. The end of the main conduit 5 which is opposite the gas bag 10 branches into two connection conduits 3 and 4, via a branch 6. Each of the connection conduits 3 and 4 is connected to a respective compressed-gas container 1 and 2. The gas containers 1 and 2 are closed by means of burster plates 7 and 8 which open simultaneously when the vehicle is subjected to significant retardation or deceleration forces, such as experienced during a collision. A retardation meter 9 senses vehicle deceleration or retardation and actuates the burster plates 7 and 8 to thereby enable the flow of gas from the containers 1 and 2 to the gas bag 10. Other types of closure devices may be utilized instead of the burster plates 7 and 8, such as conventional flow controllers. The containers 1 and 2, contain collectively, the requisite volume of gas to sufficiently inflate the gas bag 10. Although the terms "flexible container", "airbag", "air cushion", "gas bag", "gas cushion", or "cushion" are used herein, it is to be understood that such terms are used interchangeably and are not intended to limit the bag, cushion, or flexible container to only be filled with "air" or a single "gas".
Referring to FIG. 1, the gas container 1 contains oxygen and is preferably filled with helium and at most 50% by volume of another inert gas, for instance argon and/or nitrogen. The amount of oxygen present is preferably between 2.5 and 20% by volume of the total volume of gas in the containers 1 and 2. The other gas container 2 contains hydrogen and is preferably also filled with helium and at most 50% by volume of another inert gas, for instance argon and/or nitrogen. The preferred amount of hydrogen ranges from 3 to 15% by volume of the total gas volume in the containers 1 and 2. The containers 1 and 2 preferably contain the same inert gas or inert gas mixture. The most preferred inert gas is helium, constituting almost all of the inert gas present in the containers 1 and 2.
The retardation meter 9, included in the apparatus 15, senses deceleration of the vehicle in which the meter 9 is installed. The retardation meter 9 preferably comprises one or more output provisions that generate one or more signals, such as electrical control signals, indicating that sufficient deceleration or retardation forces have been sensed by the meter 9. Such forces are representative of an abrupt halt or collision involving the vehicle. The retardation meter 9 may also comprise an adjustment provision for varying the amount of deceleration force that must be sensed by the meter 9, e.g. a threshold level, in order to generate one or more output signals.
In the event the retardation meter 9 senses a sufficient retardation or deceleration force and so indicating vehicle collision, the burster plates 7 and 8 on both containers 1 and 2 are activated, i.e. ruptured or burst. The plates 7 and 8 are preferably activated by the signal output provisions of the retardation meter 9. As a result, the gas contained in the two containers 1 and 2 flows into the main conduit 5. The burster plates 7 and 8 can be of known construction and may include an explosive charge to effect their rupture. The explosion generated to burst the burster plates 7 and 8 ignites the oxygen-hydrogen mixture resulting in a chemical reaction that forms water. As a result of this reaction, the temperature of the gases is raised considerably, thereby adequately compensating for the cooling effect caused by the free expansion of the inert gas, such as helium, nitrogen and/or argon. This effectively reduces the volume of gas otherwise required to adequately inflate the gas bag 10.
Because it is not recommended to store an oxygen-hydrogen mixture in one and the same container for safety reasons, these gases are held in separate containers. The containers are opened simultaneously upon sufficient deceleration of the vehicle, and the gases, i.e. oxygen and hydrogen, combine before they reach the gas bag 10.
It is extremely important that the pressurized containers such as the containers 1 and 2, used for filling collision-activated airbags such as the gas bag 10, do not leak and will remain under the necessary pressure for many years after being filled. Since highly sensitive helium leakage detectors are available, it is convenient to use helium as a constituent of the gas for inflating the gas bag 10.
FIG. 2 illustrates another preferred embodiment inflation apparatus 35 comprising a main conduit 25 which extends from a gas cushion 28, which is shown partially filled. The gas cushion 28 is mounted in a holder device 27. The end of the main conduit 25 distal from the gas cushion 28 branches at a branch 26 into two connection conduits 23 and 24, each of which is connected to a respective compressed gas container 21 and 22. The outlets of the gas containers 21 and 22 are provided with rupture provisions, for instance in the form of a burster plate or disc, which may be ruptured or otherwise opened to provide instantaneous free passage of the gas from containers 21 and 22. This free passage of gas occurs simultaneously, or nearly so, in the event retardation or collision forces powerful enough to burst the plate or disc, are applied to the apparatus 35. The containers 21 and 22, together, contain the volume of gas needed to fill the gas cushion 28. The inflation apparatus 35 may further comprise a retardation meter in communication with the closure devices as described in conjunction with the inflation apparatus 15 illustrated in FIG. 1. Other types of closure devices or rupture provisions may be utilized.
The gas cushion 28 is secured in the holder 27. An ignition device, which may be a spark generating device, is mounted in the main conduit 25 adjacent an outlet orifice proximate the gas cushion 28, or in the vicinity of the outlet orifice of the holder 27, or near the gas containers 21 and 22 adjacent the opening of the conduit 25. The ignition device may function as an opening device that activates the rupture provisions or other closure device to enable gas to flow from the containers 21 and 22 to the cushion 28. In such a configuration, it is preferred to use burster plates that are ruptured by an explosive charge. Activation of the charge can be effected by the ignition device.
The first container 21 contains oxygen and is preferably filled with an inert gas, for instance argon, helium, nitrogen or a mixture of two or more of these gases. The amount of oxygen in the container 21 is preferably between 2.5 and 20% by volume of the total volume of gas in the two containers 21 and 22. The other container 22 contains hydrogen and is also preferably filled with inert gas. The amount of hydrogen present in the container 22 is preferably 3 to 15% by volume of the total volume of gas in the two containers 21 and 22. The containers 21 and 22 preferably contain the same inert gas or gas mixture. Helium is the most preferred inert gas.
When the vehicle is subjected to powerful retardation or deceleration forces, the weakening at the outlet of the gas containers, i.e. the rupture provisions, which in the preferred embodiment inflation apparatus 35 are bursting plates, will rupture and therewith create an opening through which gas is able to flow to the main conduit 25 from both containers 21 and 22. When a given predetermined amount of gas has flowed into the flexible cushion 28, the ignition device will generate a spark which causes the oxygen-hydrogen mixture to explode and therewith react to form water. The temperature is raised considerably by this reaction, which more than compensates for the cooling effect resulting from the free expansion of the inert gas such as helium, nitrogen, and/or argon. This enables the amount of gas required to fill the cushion 28 to be significantly reduced.
As previously noted, since it is not safe to store an oxygen-hydrogen mixture in one and the same container, these gases are stored separately in containers 21 and 22. The containers are opened simultaneously so that the gases will mix, or at least partially mix, prior to reaching the cushion 28.
As was also previously noted, it is extremely important to ensure that the pressurized containers 21 and 22 used to fill the gas cushion 28 in the event of a collision, do not leak and that they will remain pressurized at the requisite pressure for many years after being filled. Because highly sensitive helium-leakage testing devices are commercially available, it is appropriate to include helium as a constituent of the gas used in this regard.
FIG. 3 illustrates another preferred embodiment inflation apparatus 55 comprising two gas containers 41 and 42 and separate conduits 43 and 44 extending from the respective containers 41 and 42. The gas containers 41 and 42 preferably contain the oxygen and hydrogen and inert gas mixtures previously described in conjunction with the inflation apparatuses 15 and 35. The conduits 43 and 44 are connected to a gas cushion 48 through a mixer 49, which may also function as a holding device similar to the previously described holder device 27. The inflation apparatus 55 may further comprise an ignition device, a retardation meter, and rupture provisions or closure devices as utilized in the previously described apparatus 35. The mixer 49 includes a mixing chamber having a plurality of openings that connect or provide communication with the gas cushion 48. The mixer 49 is configured to present minimal resistance to the flow of gas to the gas cushion 48. In this embodiment, the ignition device is preferably mounted in the mixing chamber of the mixer 49.
In this preferred embodiment shown in FIG. 3, the gas mixture is ignited when a certain proportion of the total gas volume of the two gas containers 41 and 42 has passed into the gas cushion 48. This ignition may be caused to occur after a predetermined time period has lapsed after opening the two gas containers 41 and 42. The rate at which the gas cushion 48 is filled will decrease with time, because the pressure drop in the gas containers 41 and 42 will not permit all of the available gas volume to fill the gas cushion 48.
Ignition of the gas mixture results in a marked and rapid increase in the temperature of the entire volume of gas in the gas cushion 48, which, in turn, results in a significant increase in the volume of gas in the gas cushion 48. The mixture is ignited when at least 10% of the total volume of gas in the containers 41 and 42 has passed through the mixer 49, the volumetric capacity of which is normally small in relation to the volumetric capacity of the gas cushion 48. Preferably, the gas mixture is ignited when at least 30% of the total gas volume has reached the gas cushion 48. It is most preferred that at least 75% of the total volume of gas in the containers 41 and 42 will have passed into the flexible gas cushion 48 before the gas mixture is ignited. According to one particularly most preferred embodiment, the gas cushion 48 will contain from 80 to 90% of the total gas volume when the gas mixture is ignited.
FIG. 5 illustrates yet another preferred embodiment inflation apparatus 105 comprising two gas containers 81 and 82, a flexible and inflatable gas cushion 88, a conduit assembly described in greater detail below, and a sliding duct assembly 95. The gas containers 81 and 82 preferably contain the oxygen, hydrogen, and inert gas mixtures previously described in conjunction with the inflation apparatuses 15, 35, and 55. The gas container 81 is connected to the sliding duct assembly 95 by a flow port 83. Similarly, the gas container 82 is connected to the sliding duct assembly 95 by a flow port 84. The conduit assembly generally comprises a first conduit member 85 extending from the opening of the gas cushion 88 to a branch 86. The conduit assembly further comprises a first conduit leg 90 and a second conduit leg 91 as shown in FIG. 5. Each of the legs 90 and 91 are connected to the sliding duct assembly 95 and the branch 86.
The sliding duct assembly 95 is in many respects similar to the previously described closure devices or rupture provisions. The sliding duct assembly 95 provides apertures through its walls for connection to the noted conduit legs 90 and 91, and flow ports 83 and 84. The sliding duct assembly 95 comprises a receiving chamber that houses a first slidable member 96 disposed between the first conduit leg 90 and the flow port 83. The sliding duct assembly 95 further comprises a second slidable member 100 disposed between the second conduit leg 91 and the flow port 84. The second member 100 is also enclosed within the receiving chamber of the sliding duct assembly 95. Each slidable member 96 and 100 is slidable between one of two positions. In a first closed position shown in FIG. 5, the slidable member 96 or 100 blocks flow of gas from a gas container, such as container 81 or 82, to a respective conduit leg 90 or 91. In a second state shown in FIG. 6, each slidable member 96 or 100 is slid within the sliding duct assembly 95 to an open position such that an aperture defined within the slidable member is aligned with the flow port 83 or 84 of the gas container and the conduit leg 90 or 91. Specifically, the slidable member 96 defines an aperture 97 extending through the thickness of the member 96 as shown in FIGS. 5 and 6. When the member 96 is moved to its open position as depicted in FIG. 6, the aperture 97 is aligned with the conduit leg 90 and the flow port 83, thereby enabling gas from the container 81 to flow therethrough. Similarly, the slidable member 100 also defines an aperture 101 through which gas contained in the gas container 82 can flow through the flow port 84 and into the conduit leg 91 when the slidable member 100 is moved to its open position.
Most preferably, the apertures 97 and 101 provided in the slidable members 96 and 100 are defined at a location along the length of each member a particular distance such that when each member is slid to its open position, the apertures 97 and 101 are aligned with the openings, i.e. conduits and flow ports, on either side of the member. Referring to FIG. 5, when the slidable member 96 is slid to its open position, i.e. the member 96 is positioned to the left until the left end of the member 96 contacts or otherwise abuts the left end wall of the duct 95, the aperture 97 is generally aligned between the flow port 83 and the opening for the conduit leg 90. This alignment is shown in FIG. 6. Likewise, the slidable member 100, when moved to its open position as shown in FIG. 6, is placed in contact with, or generally abutted against the right end wall of the duct 95.
It is preferred to utilize a thin, rupturable sealing member disposed within or at the distal end of the flow ports. Such sealing members minimize leakage of the contents of a gas container, and also guard against the entry of contaminants or other unwanted agents into a gas container. Most preferably, the sealing member is a thin metallic foil that when exposed to the pressure of the interior of a gas container, ruptures to allow the gas or gases within the container to escape. The sealing member is preferably disposed adjacent a slidable member so that the membrane only ruptures when the slidable member moves into its open position. An example of a preferred rupturable sealing member is member 83a shown in FIG. 5. Upon activation of the apparatus 105, as shown in FIG. 6, the member 83a is ruptured to allow gas to flow from the container 81 through the flow port 83 and into the aperture 97 of the slidable member 96. Although only one sealing member is shown in FIG. 5, i.e. member 83a, it is to be understood that the present invention includes the use of one or more rupturable sealing members disposed within, or at the distal end of, a flow port.
The sliding duct assembly 95 further comprises a priming wire 92 extending between the gas cushion 88 and the medial region of the duct 95. An explosive charge 94 is preferably positioned within the central medial of the duct 95 as shown in FIG. 5. One end of the priming wire 92 is positioned proximate the medial region of the duct 95, and preferably in electrical association with the explosive charge 94, such that when the charge 94 is ignited, the wire 92 will also be ignited. The other end of the priming wire 92 is positioned near the opening of the gas cushion 88, and most preferably at the outlet of the conduit 85 such as at location 93.
Upon sensing sufficient retardation or deceleration forces, as described in conjunction with the apparatuses 15, 35, and 55, the explosive charge 94 is ignited. A deceleration meter, as previously described, may be utilized to ignite the explosive charge 94. This ignition also ignites the priming wire 92. The explosive forces resulting from activation of the charge 94 cause the slidable members 96 and 100 to each move toward its respective open position. In this open configuration, each aperture 97 and 101 is aligned with the respective openings of the gas containers 81 and 82 via the flow ports 83 and 84. Accordingly, the gas containers 81 and 82 are opened at exactly the same time. Hydrogen contained in a gas mixture, such as within the gas container 81, will flow through the port 83, through the aperture 97 in the slidable member 96, through the conduit branch 90 and the branch 86, into the conduit 85 and into the gas cushion 88. Similarly, oxygen in the other gas mixture, such as in the gas container 82, will flow through the port 84, through the aperture 101 in the slidable member 100, through the second conduit leg 91, through the branch 86, into the conduit 85, and into the gas cushion 88. The gases will mix when they flow through the branch 86, the conduit 85, and the gas cushion 88.
The burning of the priming wire 92 ignites the hydrogen and oxygen gas mixture within the gas cushion 88. As will be appreciated, there exists some finite time period within which a certain amount of gas enters the gas cushion 88 after explosion of the charge 94. This time period depends upon the explosion time, rate of travel of the members 96 and 100, the initial pressure of the gas mixtures in the containers 81 and 82, as well as the dimensions of the openings utilized in the flow ports 83, 84, the apertures 97, 101, and the conduits 90, 91, 86, and 85. Once having determined or estimated this time period, the length of the priming wire 92 is determined based upon its burn rate so that the time period associated with the burning of the wire 92 is matched to the time period allowing for entry of the desired amount of gas into the gas cushion 88.
In all of the previously described embodiments, it is particularly preferred that the gas containers 1, 2, 21, 22, 41, 42, 81, and 82 have certain features as follows. The openings or outlet ports of the containers are of a size or diameter such that a proper rate of pressure increase and inflation duration of the bag or cushion is obtained. The rate of pressure increase in a bag undergoing inflation should be sufficient to provide a force absorbing cushion for vehicle occupants, but not be too great such that the bag ruptures. Similarly, the inflation duration should be such that the bag is sufficiently inflated during the time period within which the occupants may strike the passenger compartment. The size or diameter of the gas container opening is also dependent upon the volumetric capacity of the bag or cushion to be inflated. It is to be understood that the various aspects of each of the previously described embodiments may, where appropriate, be combined in one or more inflation systems.
Furthermore, it is preferred that all of the previously described gas bag 10 or gas cushions 28, 48, and 88 comprise an inner layer or liner of heat reflecting material. It is most preferred that the bag 10 or cushions 28, 48, and 88 also comprise a layer of a material having a relatively low thermal conductivity and a relatively low thermal capacity. FIG. 4 illustrates a cross-section of a wall of any of the bag 10 or cushions 28, 48, and 88. This wall, designated as 75, preferably comprises an inner layer 62 of heat reflecting material. The layer 62 provides an inwardly facing and heat reflecting surface 60. Adjacent the layer 62, is a medial layer 64 of a material having a relatively low thermal conductivity and low thermal capacity. The outer layer 66 of the wall 75 is preferably a force absorbing material adapted for use in airbags. The outer layer 66 provides an outer surface 68. The layer 62 of heat reflecting material can be formed from a wide array of materials such as, but limited to, aluminum or other metal foils. The layer 64 of low thermal conductivity and capacity material can be formed from an assortment of materials including, but not limited to, polyester materials such as MYLAR, and polystyrene. The outer layer 66 can be formed from known materials typically employed in airbag construction.
In all of the foregoing embodiments, ignition of the gas contained in, or entering, the bag or cushion can be performed directly in the bag or cushion. As a result, expansion of the ignited gas acts directly upon the bag or cushion. No energy losses occur from transferring ignited gas from a separate combustion chamber through one or more conduits, to the bag or cushion. Moreover, the energy released as a result of the combustion reaction heats the gas mixture and compensates for the previously described cooling effect associated with gas expansion.
All of the noted inflation systems provide a significant advance in the art of inflatable safety restraint systems and force absorbing airbags or gas cushions. The inflation systems described herein can be used for relatively rapid bag or cushion inflation. Accordingly, the systems can be utilized for inflating relatively large bags, such as for rear seat application. The inflation systems enable virtually unrestricted free flow of gases into the bag or cushion during inflation. Moreover, the configuration of the system, choice of gas mixtures, and combustion of the gases overcomes the prior art problems of deficient inflation.
While the foregoing details are what is felt to be the preferred embodiments of the present invention, no material limitations to the scope of the claimed invention are intended. Further, features and design alternatives that would be obvious to one of ordinary skill in the art are considered to be incorporated herein. The scope of the invention is set forth and particularly described in the claims herein below. | The present invention relates to a system for filling an empty flexible container such as an airbag with gas essentially instantaneously when the system or vehicle utilizing such system is subjected to sufficient deceleration forces, such as experienced during a collision. The gas-filled container functions as a force absorbing cushion which protects occupants in the vehicle against injuries. The system includes pressure vessels filled with gas under high pressure, one or more conduits connecting the pressure vessels with the flexible container, provisions for opening the connection between the pressure vessels and the flexible container upon sensing retardation or deceleration forces that exceed some threshold value, a container holding or mixing device, and a retardation meter. The pressure vessels are each sealed by a closure device and each has a respective connection conduit which joins the pressure vessels to the flexible container. One pressure vessel contains oxygen and an inert gas. The other pressure vessel contains inert gas and hydrogen. The inert gas is helium, argon and/or nitrogen. | 1 |
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
[0001] This invention was made with government support under Grant No. 8P01EB002014-09 and 8R01EB000215-16 awarded by the National Institute of Health. The United States Government has certain rights in this invention.
BACKGROUND OF THE INVENTION
[0002] The field of the invention is nuclear magnetic resonance imaging methods and systems. More particularly, the invention relates to the production of MRI perfusion images.
[0003] Any nucleus which possesses a magnetic moment attempts to align itself with the direction of the magnetic field in which it is located. In doing so, however, the nucleus processes around this direction at a characteristic angular frequency (Larmor frequency) which is dependent on the strength of the magnetic field and on the properties of the specific nuclear species (the magnetogyric constant gamma y of the nucleus). Nuclei which exhibit this phenomena are referred to herein as “spins”.
[0004] When a substance such as human tissue is subjected to a uniform magnetic field (polarizing field B 0 ), the individual magnetic moments of the spins in the tissue attempt to align with this polarizing field, but precess about it in random order at their characteristic Larmor frequency. A net longitudinal magnetization M 0 is produced in the direction of the polarizing field, but the randomly oriented magnetic components in the perpendicular, or transverse, plane (x-y plane) cancel one another. If, however, the substance, or tissue, is subjected to a magnetic field (excitation field B 1 ) which is in the x-y plane and which is near the Larmor frequency, the net longitudinal magnetization, M 0 , may be rotated, or “tipped” into the x-y plane to produce a net transverse magnetic moment M t , which is rotating, or spinning, in the x-y plane at the Larmor frequency. The practical value of this phenomenon resides in the signal which is emitted by the excited spins after the excitation signal B 1 is terminated. There are a wide variety of measurement sequences in which this nuclear magnetic resonance (“NMR”) phenomena is exploited.
[0005] When utilizing NMR to produce images, a technique is employed to obtain NMR signals from specific locations in the subject. Typically, the region which is to be imaged (region of interest) is scanned by a sequence of NMR measurement cycles which vary according to the particular localization method being used. The resulting set of received NMR signals are digitized and processed to reconstruct the image using one of many well known reconstruction techniques. To perform such a scan, it is, of course, necessary to elicit NMR signals from specific locations in the subject. This is accomplished by employing magnetic fields (G x , G y , and G z ) which have the same direction as the polarizing field B 0 , but which have a gradient along the respective x, y and z axes. By controlling the strength of these gradients during each NMR cycle, the spatial distribution of spin excitation can be controlled and the location of the resulting NMR signals can be identified.
[0006] Perfusion as related to tissue refers to the exchange of oxygen, water and nutrients between blood and tissue. The measurement of tissue perfusion is important for the functional assessment of organ health. Images which show by their brightness the degree to which tissues are perfused can be used, for example, to assess the scope of brain tissues which have been damaged by a stroke, or to assess the scope of myocardial tissue damage resulting from a heart attack.
[0007] A number of methods have been used to produce perfusion images using magnetic resonance imaging techniques. One technique, as exemplified by U.S. Pat. No. 6,295,465, is to determine the wash-in or wash-out kinetics of contrast agents such as chelated gadolinium. In addition to the need for injection of a contrast agent, these methods require the acquisition and subtraction of baseline images.
[0008] Another class of MR perfusion imaging techniques attempts to measure blood flow by “tagging” or “labeling” spins flowing into a region of interest by applying RF excitation in an adjacent region and then acquiring image data from the region of interest. By subtracting a baseline image acquired without RF tagging, perfusion information is acquired and imaged. Repeated acquisitions and averaging of the results is used to improve perfusion image signal-to-noise ratio (SNR). Examples of these techniques are disclosed in U.S. Pat. Nos. 5,402,785; 6,285,900; 5,846,197; and 6,271,665 and the publications “Quantification Of Relative Cerebral Blood Flow Change By Flow-Sensitive Alternating Inversion Recovery Technique; Application to Functional Mapping” by S. G. Kim Magn. Reson. Med. 34(3):297-301, 1995; “MR Perfusion Studies With T 1 -Weighted Echo Planar Imaging”, by K. K. Wong et al Magn. Reson. Med. 34:878-887 (1995); and “QUIPSS II With Thin-Slice TI, Periodic Saturation” A Method For Improving Accuracy Of Quantitative Perfusion Imaging Using Pulsed Arterial Spin Labeling” by Luh et al Magn. Reson. Med. 41:1246-1254 (1999).
[0009] In all of these methods the amplitude or amplitude change of the NMR signal at each image voxel is the measure of perfusion at that location in the subject tissue. The basic structure of these NMR perfusion sequences includes one tagging slice and one imaging slice as shown in FIG. 3, separated by a distance (e.g., 5 mm) and excited at two different moments (e.g., 500 ms apart). If the tagging pulse inverts the magnetization by 180° in a tagging slice and there is flow of one cm/sec in the direction of the imaging slice, then the total magnetization M 0 in this slice will be reduced when transverse magnetization is produce by an imaging pulse sequence. The detected NMR signal in a given voxel into which tagged spins flow will, therefore, be lower than without tagging. A similar effect can be obtained by pure saturation, i.e., by applying a tagging pulse flip angle equal to 90°. In this case, the signal reduction will be smaller. The levels of longitudinal spin magnetization M 0 of inflowing tagged blood are shown in FIG. 4. Point Inv marks the longitudinal magnetization value for a 180° pulse, point Sat for a 90° pulse, and point Norm for a 0° tagging pulse. The general principle of flow detection is to subtract two images, one with no tagging and one which has been tagged. In the experiment illustrated in FIG. 3, only one flow velocity can be detected—exactly one cm/sec. Slower flowing blood will not arrive at the time of image acquisition; faster flowing blood will overshoot the slice. The sensitivity of this method is poor for several reasons: the T 1 relaxation of blood is less than one second at a polarizing field of 3T, and the total volume of the microvascular structure is only a small part of the imaging voxel. To improve sensitivity, usually a plurality of imaging pairs is acquired and the differential signals are averaged. The repetition time (TR) has to be long enough for longitudinal magnetization to relax fully.
SUMMARY OF THE INVENTION
[0010] The present invention is a method for producing a perfusion image by repeatedly RF tagging spins flowing into an image slice and modulating the RF tagging in accordance with a tagging pattern over a modulation time period, acquiring a set of time course MR images from the image slice over a time period that includes the modulation time period; detecting voxels in the MR images which vary in accordance with the tagging pattern; and indicating perfusion into the detection voxels.
[0011] Both the RF tagging and image acquisition can be done in a single pulse sequence which is repeated to both play out the tagging pattern and acquire the time course MR images. A variety of different tagging patterns can be used and different techniques may be used to detect the tagging pattern in time course image voxels. Perfusion can be indicated in an image which indicates by the brightness of its pixels the perfusion detected in corresponding time course image voxels. Brightness may indicate flow velocity or flow volume.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] [0012]FIG. 1 is a pictorial view with parts cut away of an MRI system which employs the present invention;
[0013] [0013]FIG. 2 is a graphic representation of a preferred pulse sequence used to operate the MRI system of FIG. 1;
[0014] [0014]FIG. 3 is a schematic representation of an image slice and tagging slice used to produce MRI perfusion images;
[0015] [0015]FIG. 4 is a graphic representation of the recovery of longitudinal spin magnetization after the application of a tagging RF pulse;
[0016] [0016]FIG. 5 is a flow chart of a preferred method of practicing the present invention;
[0017] [0017]FIG. 6 is a pictorial representation of image data sets acquired over a time course study according to the present invention;
[0018] [0018]FIGS. 7 a - 7 d are pictorial representations of k-space image reconstruction method used in the preferred embodiment of the invention;
[0019] [0019]FIG. 8 is a graphic illustration of the modulation of the RF tagging that is performed in accordance with a preferred embodiment of the invention;
[0020] [0020]FIG. 9 is a pictorial view showing RF tagging of flowing spins on both sides of an imaging slice for bidirectional flow encoding;
[0021] [0021]FIG. 10 is a pictorial view showing RF tagging of flowing spins in two directions into a plurality of imaging slices;
[0022] [0022]FIG. 11 is a pictorial representation of a tagging slab having a plurality of separate tagging slices;
[0023] [0023]FIG. 12 is a graphic illustration of a phase encoding method of differentiating spins from the tagging slices of FIG. 11; and
[0024] [0024]FIG. 13 is a graphic illustration of a frequency encoding method of differentiating spins from the tagging slices of FIG. 11.
GENERAL DESCRIPTION OF THE INVENTION
[0025] Referring to FIG. 3, in its most basic form the present invention requires the production of an RF tagging pulse to reduce longitudinal magnetization M 0 in a tagging slice, followed by the acquisition of an MR image from an adjacent imaging slice. This pulse sequence is repeated and the flip angle φ of the RF tagging pulse is modulated in value from 0° to 180° to modulate the longitudinal magnetization M 0 within the tagging slice over a modulation period. Referring to FIG. 8, for example, the pulse sequence may be repeated sixteen times and the RF tagging pulse flip angle increased 22.5° each repetition. Over the modulation period, therefore, the longitudinal magnetization M 0 will be sinusoidally modulated in amplitude.
[0026] This same sinusoidal modulation of longitudinal magnetization M 0 will be seen a short time later in voxels of the image slice which contain spins that have perfused from the tagging slice. This modulation of the longitudinal magnetization M 0 will be reduced in magnitude due to T 1 relaxation as illustrated in FIG. 4, but the frequency of the sinusoidal modulation will be the same as that in the, tagging slice. Because the longitudinal magnetization M 0 in the image slice is modulated over the time course study, the magnitude of the transverse magnetization produced by an imaging pulse sequence will also be modulated, and the magnitude of the acquired NMR signals from voxels with flowing spins will be modulated at the sinusoidal frequency.
[0027] A perfusion image is produced by repeating the tagged pulse sequence over the modulation period and then reconstructing each acquired image in the time course study. For example, if the modulation period spans 16 repetitions as shown in FIG. 8, 512 images might be acquired during the time course study. The magnitude of each corresponding pixel in the 512 images (referred to herein as a voxel vector) is then examined to determine which pixels are modulated in intensity at the sinusoidal frequency. This examination can be done in a number of ways, but a preferred method is to cross correlate the voxel vector with a reference waveform 20 shown in FIG. 8. The reference waveform 20 is a sinusoidal waveform which corresponds to the modulation of the longitudinal magnetization caused by the tagging RF pulses during a modulation period. Those pixels which depict flowing spins that pass through the tagging slice will correlate highly with the reference waveform 20 and their corresponding pixels will be set brighter in the perfusion image. The brightness of the pixels in the perfusion image are thus determined by the pattern of NMR signal magnitude modulation during the time course study rather than a signal magnitude or a difference in signal magnitude.
[0028] This new perfusion imaging technique may be performed in either of two basic ways, which I refer to as the “dynamic flow” techniques or “static flow” techniques. The “dynamic flow” techniques employ a short TR which enables many pulse sequences to be played out before the longitudinal magnetization M 0 relaxes and the amount of M 0 modulation of spins flowing into the imaging slice is lost. This enables spins flowing over a wide range of velocities to be “captured” in any one of the series of short TR image slice acquisitions that are performed following RF tagging.
[0029] In the static flow methods of perfusion imaging described below, the pulse sequence repetition rate (TR) is longer (e.g., 2 seconds) and longitudinal magnetization of all tagged spins has relaxed before the next pulse sequence is performed. This means that tagged spins will only be captured in the image slice during the same TR as the RF tagging pulse.
[0030] An exemplary fast perfusion imaging technique will now be described in which the pulse sequence TR is short (e.g., 100 msec.) and the tagged spins can be “seen” in the imaging slice over a plurality of pulse sequence TRs. Referring again to FIG. 8, during the first pulse sequence repetition (TR 1 ), spins in the tagging slice are exposed to RF excitation, but spins flowing into the imaging slice have not yet been modulated. During the second pulse sequence (TR 2 ), the tagging slice is again irradiated with an RF tagging pulse, but now faster flowing spins have a chance to reach the image slice from the tagging slice and start affecting the acquired image. As the modulation period progresses, the longitudinal magnetization M 0 of these faster moving spins in the image slice will have a modulated magnitude waveform such as that at 22 . This waveform 22 is substantially the same as the reference waveform 20 (i.e., high correlation) but it is delayed, or phase shifted by 22.5°. If the distance between the tagging slice and the imaging slice is 10 mm and the TR of the pulse sequence is 100 ms, the velocity of fast flowing spins producing the waveform 22 is 10 cm/sec. Spins that are flowing faster than this velocity will not be detected because they will pass beyond the image slice before the next pulse sequence can be performed.
[0031] Slower moving spins can, however, be detected and their velocity indicated. Referring again to FIG. 8, spins flowing at half the speed of the fastest detected spins will reach the imaging slice in two TR periods and begin to modulate the longitudinal magnetization M 0 therein. As indicated by waveform 24 , as the modulation period is played out, spins flowing at this lower velocity (5 cm/sec. in the above example) modulate the NMR signals in the time course images. The waveform 24 is substantially the same as the reference waveform 20 , but it is delayed, or phase shifted by 45°. A similar waveform 26 is produced by very slow moving spins, but it is phase delayed even further. In other words, the phase of the modulated and correlated NMR signals contains spin flow velocity information which can be used to produce an image.
[0032] The phase of the modulated and correlated NMR signals for a pixel can be measured by cross correlating it with two reference waveforms. The first waveform 20 is a sinusoidal waveform of one phase which corresponds to the phase of maximum detectable velocity spins, and a second reference waveform 28 is phase shifted 90° therefrom. The NMR signal waveform for each image pixel is cross correlated with the first reference waveform 20 to produce a first correlation value 1 and it is cross correlated with the second reference waveform 28 to produce a second correlation value Q. The velocity of the flowing spins at each pixel is proportional to arctan (Q/I). In addition, the volume of flow is proportional to:
V∝{square root}{square root over (I 2 +Q 2 .)}
[0033] The “static flow” technique of implementing the present invention employs a pulse sequence in which spins are tagged in the tagging slice (FIG. 3) and NMR signals from the same tagged spins are captured during image acquisition in the same TR as they flow through the imaging slice. After image acquisition the longitudinal magnetization is allowed to recover before repeating the pulse sequence. This means that only NMR signals produced by those spins having a specific range of velocities will be “seen” with a modulated amplitude because only spins flowing at a speed which places them in the imaging slice at the moment the imaging pulse sequence is performed will produce modulated transverse magnetization. As with the dynamic flow techniques, a series of tagged pulse sequences are applied where the RF tagging pulse flip angle is modulated over a preselected modulation period. For each voxel the NMR signal magnitudes in the resulting time course images are cross correlated with a reference waveform and the resulting correlation value is used to control the corresponding pixel brightness in a perfusion image.
[0034] These techniques can be easily extended to measure flow from a plurality of tagging slices into a single imaging slice. Such an arrangement is shown in FIG. 9 where flow from left to right is measured into an imaging slice by tagging moving spins in a first tagging slice. Flow from right to left into the imaging slice is also measured at the same time by tagging moving spins in a second tagging slice located on the opposite side of the imaging slice. The trick is to modulate longitudinal magnetization in tagging slice 1 at a different frequency than the modulation in tagging slice 2 . For example, the modulation period for tagging slice 1 may be sixteen TR as described above, but the modulation period for tagging slice 2 may be nineteen TR. In this case the NMR signal modulation waveform for each image pixel is cross correlated with reference waveforms at both frequencies to measure perfusion from each of the two tagging slices. This concept can be expanded to include more than one imaging slice and more than two tagging slices as shown in FIG. 10.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0035] Referring to FIG. 1, an MRI magnet assembly 10 has a cylindrical bore tube 12 extending along a z-axis for receiving a supine patient 14 supported on a table 16 . The table 16 may move in and out of the bore tube 12 so as to position the patient 14 along the z-axis within the volume of the bore tube 12 .
[0036] Coaxially surrounding the bore tube 12 is a whole-body RF coil 18 for exciting the spins of the patient 14 into resonance, as has been described. Whole-body gradient coils 20 surround both the bore tube 12 and the RF coil 18 and are also coaxial with the z-axis, to provide x, y and z gradient fields G x , G y and G z as required for MRI imaging. The gradient coils 20 are driven by gradient amplifiers (not shown). The polarizing magnetic field B 0 , aligned with the z-axis is generated by a superconducting magnet coil 28 coaxial with but outside the bore tube 12 , the RF coil 18 and the gradient coils 20 . The superconducting magnet coil 28 has no external power supply but operates on an initial current which continues unabated in the zero resistivity windings of the superconducting magnet coil 28 .
[0037] Interposed between the superconducting magnet coil 28 and the gradient coil 20 is a set of shim coils 30 which are used to correct the homogeneity of the polarizing field B 0 as is understood in the art. A set of mechanical linkages and insulators (not shown) rigidly connect each of these coils 18 , 20 , 28 and 30 together to the bore tube 12 so as to resist relative motions generated by the interaction of their various electromagnetic fields.
[0038] When a local coil assembly 8 is used in a general purpose system such as that described above, the whole-body gradient coils 20 and whole-body RF coil 18 are disconnected. The local coil assembly 8 is connected to the x, y and z gradient amplifiers (not shown) on the NMR system and it is connected to the system's transceiver through a transmit/receive switch. The preferred embodiment employs a 3 Tesla MRI system manufactured by Bruker Analytische MeBtechnik GmbH and sold under the trademark BIOSPEC 30/60.
[0039] Because the gradient fields are switched at a very high speed when an EPI sequence is used to practice the preferred embodiment of the invention, local gradient coils are employed in place of the whole-body gradient coils 20 . These local gradient coils are designed for the head and are in close proximity thereto. This enables the inductance of the local gradient coils to be reduced and the gradient switching rates increased as required for the EPI pulse sequence. The local gradient coil assembly 8 also includes a local brain RF coil. In the preferred embodiment, it is a 16 element bandpass endcapped birdcage coil. This brain RF coil is designed to couple very efficiently to the brain of the subject and less efficiently to the lower part of the head. This results in improved brain image quality compared with larger general purpose head coils that couple uniformly to the entire head as well as the neck. An RF shield surrounds the local brain coil and interior to the local gradient coil. This shield isolates RF radiation from the local gradient coil. The shield is designed to avoid perturbation of time varying gradient fields. For a description of these local gradient coils and the RF coil which is incorporated herein by reference, reference is made to U.S. Pat. No. 5,372,137 filed on Jan. 19, 1993 and entitled “NMR Local Coil For Brain Imaging”.
[0040] To practice the present invention a series of images are acquired from an imaging slice over a period of time. Each image acquisition is preceded by tagging one or more tagging slices with an rf tagging pulse. During this time course image acquisition the rf tagging pulse is modulated in a prescribed manner.
[0041] Referring particularly to FIG. 2, the preferred pulse sequence used to practice the invention is an EPI pulse sequence preceded by a tagging RF pulse 240 . The tagging RF pulse 240 is produced in the presence of a slice select gradient pulse 242 to generate transverse magnetization in a tagging slice thus reducing the longitudinal magnetization M 0 . This is followed by a crusher gradient pulse 244 directed along the slice select axis G z to dephase the transverse magnetization. At a predetermined interval (IR) thereafter, the EPI pulse sequence is performed to acquire data from the adjacent image slice.
[0042] The EPI pulse sequence begins with a 90° RF excitation pulse 250 which is applied in the presence of a G z slice select gradient pulse 251 to produce transverse magnetization in a slice typically ranging from 1 to 10 mm thick. The excited spins are rephased by a negative lobe 252 on the slice select gradient G z and then a short time interval elapses before the readout sequence begins. For a 256×256 matrix a total of 128 separate NMR echo signals (or “views”), indicated generally at 253 , are acquired during the EPI pulse sequence along with 8 overscan views indicated generally at 254 . Each NMR echo signal 253 is a different view which is separately phase encoded to sample a line in k-space.
[0043] The NMR echo signals 253 are gradient recalled echo's produced by the application of an oscillating G x readout gradient field 255 . The readout sequence is started with a negative readout gradient lobe 256 and the echo signals 253 are produced as the readout gradient oscillates between positive and negative values. A total of 256 samples are acquired of each NMR echo signal 253 during each readout gradient pulse 255 . The successive NMR echo signals 253 are separately phase encoded by a series of G y phase encoding gradient pulses (or “blips”) 258 . The first phase encoding gradient pulse is a negative lobe 259 that occurs before the echo signals are acquired to encode the first overscan view at k y =−8. Its area is such that after the overscan views are acquired the center of k y space is reached and a first central view 260 is acquired. One phase encoding pulse is deleted at 261 such that a second central view 262 is acquired with an opposite polarity readout gradient 255 . Subsequent phase encoding pulses 258 occur as the readout gradient pulses 255 switch polarity, and they step the phase encoding monotonically upward through k y space (k y =1−136). These 128 views that sample one-half of k-space are thus acquired in a centric view order, that is, a view order in which k-space is sampled beginning at the center of k-space and extending toward the periphery of k-space.
[0044] The two central views 260 and 262 are used for group delay, phase and frequency-offset correction. One advantage of the preferred pulse sequence is that these two views are acquired at minimal delay after the 90° pulse 250 and exhibit high SNR. As described below, the overscan views 254 are needed to produce the phase map that is necessary to center the central echo on the central pixel, which is required to fill the empty views of k-space (k y =−8 to +8).
[0045] This tagged EPI pulse sequence is repeated from 32 to 256 times to acquire a corresponding number of images over a time course of 60 seconds to 4.5 minutes depending on the specific TR prescribed. The tagging RF pulse 240 is modulated during this study by varying its flip angle to velocity encode moving spins. In all the embodiments described below, the pulse sequence TE is set to 15 ms and a 256×256 voxel image is acquired over a 24 cm field of view. The receiver bandwidth is set to 250 kHz and a slice thickness of 1.5 mm is acquired. For the dynamic flow embodiments described below pulse sequence TR is set to 133 ms and a 1.5 mm thick tagging slice is irradiated with a tagging rf pulse 240 applied 50 ms prior to the start of the EPI pulse sequence (IR=50 ms) with resolution less than 128×128. In the dynamic flow methods a total of 450 time course images are acquired in 60 seconds with tagging slices separated from the imaging slice by 5, 10 or 15 mm. In the static flow frequency and phase encoding embodiments described below the pulse sequence TR is set to 2 seconds and the 10 to 70 mm thick tagging slice is separated from 2 to 10 mm from the imaging slice. The RF tagging pulse 240 is applied one second before image acquisition (IR=1 s) and a total of 135 time course images are acquired in 4.5 minutes.
[0046] Referring particularly to FIG. 5, the time course images are acquired as described above and indicated at process block 300 . At the completion of the scan a series of partial k-space data sets are stored and an image is reconstructed from each of these partial k-space data sets as indicated at process block 302 . Each partial k-space data set is completed using a method similar to that described by D. E. Purdy, “A Fourier Transform Method Of Obtaining High Resolution Phase Maps For Half-Fourier Imaging,” Proc. SMRM, 7 th Annual Meeting, San Francisco 1998, pg. 968.
[0047] [0047]FIG. 7 a is a diagram of k-space in which the views actually acquired are indicated by the shaded area. In addition to acquisition of half k-space views 129 - 256 , N overscan lines are acquired adjacent to line 128 . In the preferred embodiment N is set to 8 , although the software enables other values to be set. Acquisition therefore begins with line 128 and proceeds to line 256 .
[0048] According to the symmetries of the Fourier transform, if the raw k-space data have a symmetrical real part (I) and an asymmetrical imaginary part (Q), then the image is purely real. The first step, therefore, in reconstruction is to center the data on line 129 of k-space such that I and Q have the requisite symmetries. The reduced I and Q matrices are formed from the lines of k-space shown in FIG. 7 b, inserting zeroes in spaces B and C. These data are Fourier-transformed to produce 256×256 real and imaginary images. From these images, a pixel-by-pixel phase map (arc tan(Q M /I M )), where I M and Q M refer to the image real and imaginary intensities, is constructed and saved. This phase map has dimensions of 256×256, but is smoothed in the y direction as would be expected for 2N resolution.
[0049] The original data set (FIG. 7 a ) is transformed to image space by performing a 2-D Fourier transformation and the phase map is used to correct the values such that all information resides in I M and no intensity is left in Q M except for small discrepancies between the actual y axis image resolution and the y axis smoothed phase map. The phase-corrected image is then brought back to k-space by inverse FT (FIG. 7 c ). The data are now centered on line 129 . With the data centered and phase corrected, the top part of k-space is filled by the Hermitian conjugate of the lower part as shown in FIG. 7 d:
raw(− kx, −ky )=raw*( kx, ky )
[0050] It is also necessary to zero-fill one-half of a vertical column, as indicated in FIG. 7 d. Finally, the data of FIG. 7 d are transformed to image space by performing a two-dimensional Fourier transformation thereof. The final image is produced by forming a magnitude image [I M 2 +Q M 2 ] 1/2 .
[0051] As shown in FIG. 6, these images are organized as set of 256×256 element 2-D arrays 304 in which each element stores the complex value of the NMR signal from one voxel in the scanned slice. Each image array 304 can be used to directly produce an anatomical image of the slice. While each array 304 is a “snap shot” of the slice at a particular time during the time course study, the entire NMR image data set may also be viewed as a single 256×256×n 3-D data array 306 in which the third dimension is time.
[0052] he time course NMR image data for one voxel in the array 306 is referred to herein as a time course voxel vector. One such vector is illustrated in FIG. 6 by the dashed line 308 . Each time course voxel vector 308 indicates the magnitude of the NMR signal at a voxel in the image slice over the time course study. The resulting time domain voxel vector 308 reveals very clearly any variations in value due to variations in the magnetization of spins flowing into the slice from the tagging slice.
[0053] Referring again to FIG. 5, the next step as indicated at process block 312 is to correlate the variations in each voxel vector 308 with a reference vector. The reference vector will be different depending on the particular technique used, but the general concept is to measure the degree of similarity between the variations in voxel vector values and the variations in the rf tagging pulse flip angle over the same time course. The correlation values may then be used to produce an image indicative of perfusion as indicated at process block 314 . This correlation operation may be performed by Fourier transform, locking mixer or phase-sensitive detection. The objective is to measure the degree to which each voxel vector resembles, or matches, the pattern of the reference waveform. In the preferred embodiment a cross correlation method such as that described in U.S. Pat. No. 5,603,322 is used in which the dot product of the voxel vector and the reference waveform is calculated.
[0054] The first embodiment of a dynamic flow method for perfusion imaging is basically the same as described above, in which two reference waveforms are used to measure the phase of the modulated signal at each voxel. The longitudinal magnetization is not allowed to fully relax before the next tagging pulse is applied by keeping the repetition time (TR) of this sequence below 200 ms. The sequence is operated under the assumption that moving blood will leave a tagging slice before the next tagging pulse is applied. If not, the subsequent tagging pulse with a different flip angle will flip magnetization again, and the final shape of a time-course signal cannot be predicted. A thinner tagging slice is therefore required. The advantage of this technique is that it discriminates between velocities in discreet steps by time of arrival to the readout slice. The fast blood tagged in the first shot will arrive at the readout slice in the second acquisition. Blood moving twice as slow will arrive in the third acquisition, three times slower blood will arrive in the fourth acquisition, and so on. Once equilibrium in tagging and readout is established, the different flow velocities will appear at the same frequency of signal modulation but at a different phase. For every pixel, two data points are created: I, by correlating the voxel vector with a cosine reference waveform, and Q, by correlating with a sine reference waveform. Arctan (Q/I) gives the phase of the NMR signal modulation, which is inversely proportional to the flow velocity.
[0055] An apparent drawback of this method is that a set of discrete velocities is measured. Lower velocities are sampled more densely than higher velocities. The other drawback lies in decay of tagging magnetization due to the relaxation time T 1 . The slower blood arrives later to the imaging slice, and the amplitude of longitudinal magnetization oscillations is reduced due to T 1 relaxation. This is not the case for the slow methods described below in which detected flowing spins always arrive in the imaging slice during the same TR. The advantage of this fast imaging technique lies in its speed: the S/N ratio increases proportionally to the ratio of the total image acquisition time to the total experiment time. The dynamic flow techniques are in general superior, although the idle time in slower imaging techniques discussed below can be used to acquire more slices.
[0056] Another embodiment of the invention employs the static flow technique, and it overcomes the spin velocity limitation of this technique discussed above by using a more complex tagging method. Referring particularly to FIG. 11, with this embodiment a thick slab is employed for tagging and this thick slab is divided into a plurality of separate slices 320 - 323 which are located at different distances from the imaging slice 324 . The time between tagging the whole slab and the acquisition of the image is 0.5 seconds, and thus the tagged spins reaching the image slice from the furthest tagging slice must travel further during this time interval and will have a higher velocity than tagged spins from the closest tagging slice. Thus, modulated NMR signals produced by spins flowing into the imaging slice over a range of different velocities can be “seen” by the imaging pulse sequence and used to produce the perfusion image.
[0057] To distinguish the different velocities of these spins, the flip angle modulation waveforms are different for each tagging slice. In this embodiment all the modulation waveforms are sinusoidal and have the same frequency and period. As shown in FIG. 12, however, the phase of each modulation waveform is different. With four tagging slices 320 - 323 , four separate spin flow velocities are encoded by using four sinusoidal modulation waveforms 325 - 328 that are shifted in phase 90° from each other. The acquired time course images may be processed as described above for the fast technique method and two orthogonal sinusoidal reference waveforms of the same frequency may be correlated with the resulting voxel vectors to produce I and Q values from which the phase can be detected. A perfusion image can then be produced in which pixels are color coded with the detected phase/spin velocity.
[0058] Only four spin flow velocities are detected using this four-slice tagging slab of FIGS. 11 and 12, corresponding to four phase-shifted modulation waveforms. Additional slices can be added to improve velocity resolution, but the generation of the resulting RF tagging pulses can become difficult. The RF tagging pulses for each tagging slice 320 - 323 are separately generated and commercially available MRI systems have a limit on the number of RF pulses that can be prescribed in a pulse sequence. It is contemplated, however, that tailored RF tagging pulses can be created in which the frequency spectrum of the pulse is modulated to produce many phase-shifted tagging slices with uniformly changing profiles. The pulse shape is derived as an inverse Fourier transform of the desired spectrum and is multiplied by a Hamming window to reduce truncation artifacts. Such tagging will produce a uniform distribution of the initial phase across a slab, allowing for uniform velocity detection.
[0059] This method can be used also for bi-directional multi-slice flow detection by exciting different slabs with different frequencies as shown in FIG. 9. In this embodiment tagging slab 1 is divided into four tagging slices which employ four phase-displaced tagging modulation sinusoidal waveforms at frequency f 1 and slab 2 is divided into four tagging slices which employ four phase-displaced tagging modulation waveforms at a second frequency f 2 . In this case each voxel vector is correlated with four reference waveforms: two at frequency f 1 , and two at frequency f 2 .
[0060] Another slow technique which is very similar to that just described uses tagging pattern frequency rather than tagging pattern phase to differentiate between spin flow velocities. Referring particularly to FIG. 11, the four tagging slices 320 - 323 in this embodiment modulate their tagging flip angle during a time course study at a different frequency. This is illustrated by the four flip angle modulation waveforms 330 - 333 in FIG. 13. In this case the modulation period of each waveform 330 - 333 is different and it is necessary to obtain time course images over a time period at least as long as the longest modulation period.
[0061] This frequency encoding technique will produce oscillations in the acquired NMR signal over the time course study at four corresponding frequencies. Faster flow will show itself at a higher frequency in a time-course. In this particular embodiment, the tagging frequency is distributed linearly across the slab and will not result in the acquired linear encoding of flow. To achieve linear encoding, one has to code a frequency inversely proportional to the spacing between the imaging slice 324 and the center of the tagging slice 320 - 323 . This can be achieved by modifying slab profiles accordingly, and creating tailored tagging pulses as described above. Then a simple Fourier transform of a time-course voxel vector will produce a frequency spectrum indicative of the frequency components therein. Flowing spins are revealed by a peak in this spectrum at a tagging modulation frequency. The position of the highest peak in the resulting spectrum indicates spin velocity. An advantage of this frequency encoding method is the possibility of distinguishing several velocities within a voxel by detecting a set of peaks in the spectrum. Linearity of flow versus frequency, while possible, is not a most desired feature. It is possible to shape tagging profiles differently to achieve a logarithmic scale of flow. This will give uniform relative steps in the velocity encoding direction.
[0062] The preferred embodiments described above all employ a sinusoidal tagging modulation waveform. It is also possible to use other, non-sinusoidal waveforms. Sinusoidal tagging uses a limited amount of the available spectrum, defined as one-half of the number of tags per cycle. Even multi-slice tagging with bi-directional flow detection will not span the available spectrum. When the spectral tagging width is increased, care has to be taken to avoid overlap with the spectrum of a subsequent tagging slab. Both spectra can be interleaved, but should not share a common harmonic to avoid cross-talk inflow detection by the correlation method. The information in the broadened spectrum is coherent, and adds, but noise is not coherent and will average. This will lead to an improved S/N ratio of detection. Special care has to be taken in development of a tagging modulation waveform shape because simple broadening of a spectrum with flat amplitude will increase the peak amplitude somewhere in the time course. The tagging amplitude cannot exceed the range of plus or minus the maximum longitudinal magnetization—the equivalent of 0° to 180° of flip angle. The velocity of flow will be detected in two steps. In the first step, a set of known shape functions with different time shifts will be used to derive a set of correlation coefficients for each imaging pixel. If the highest correlation coefficient in this set passes a threshold value (usually 0.5, but it depends on noise), it will indicate the velocity of flow. In the second step, the correlation value will be computed for this delay to derive an amplitude of oscillations that can be used to derive a volume of flow. | A perfusion image is produced by acquiring a series of time course MR images from an imaging slice. During the acquisition spins flowing into the slice are repeatedly tagged with an RF tagging pulse having a flip angle that is modulated according to a tagging pattern. Voxels in the series of reconstructed MR images having signals which vary according to the tagging pattern indicate perfusion. Perfusion images indicating either flow or velocity are produced. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to reinforced silicone elastomers. More particularly, it relates to finely divided silica fillers, useful in reinforcing fluorosilicone elastomeric compositions which have been treated with pre-hydrolyzed fluoroalkyl-functional diorganodihalogensilanes. Fluorosilicone elastomers containing silica fillers so treated show substantially improved compression set and tear strength, as well as improved handling properties.
Silicone elastomers have been widely valued for their resistance to moisture and their high and low temperature stability. Improved silicone elastomers have also been developed which exhibit better handling characteristics, as in U.S. Pat. No. 2,938,009 (Lucas), mechanical properties, as in U.S. Pat. Nos. 3,635,743 (Smith) and 3,847,848 (Beers), and solvent resistance, as in U.S. Pat. No. 4,029,629 (Jeram). All of the above patents are incorporated herein by reference. These improvements are accomplished through the use of treated fillers, usually treated finely divided silica, or by modifying the curable siloxane polymers, as with the perfluoroalkylene-substituted polysiloxanes of the aforementioned Jeram patent.
Treating silica fillers with fluorosilicone treating agents has been proposed, see e.g., copending U.S. Applications Ser. No. 252,659 filed Apr. 9, 1981, now U.S. Pat. No. 4,355,121 and Ser. No. 195,579 filed Nov. 8, 1980, now abandoned in favor of Ser. No. 368,931 filed April 16, 1982, but implementation of the concept has been resisted because of the toxicity of the treating agents (i.e., fluoroalkyl functional cyclic polysiloxanes) and the substantial modifications of existing equipment their use would entail.
It has now been discovered that finely divided silica reinforcing fillers can be treated with fluoroalkyl-functional silicone polymers without modifying conventional production apparatus and without adding costly toxicity controls. Furthermore, fluorosilicone elastomers reinforced with these fillers show improved ease of handling in mixing, milling and extrusion and also have improved mechanical properties, especially in terms of tear strength and compression set.
SUMMARY OF THE INVENTION
Accordingly, it is the object of the present invention to provide a treated silica filler for reinforcing vulcanizable elastomers which will improve the handling properties and mechanical properties of silicone elastomers made with said fillers.
It is a further object of the present invention to provide a means of improving the performance of silicone rubbers without entailing significant product process changes or toxicity precautions.
It is a further object of the present invention to provide a process for treating finely divided silica reinforcing fillers with fluoroalkyl-functional diorganopolysiloxane treating agents.
These and other objects are accomplished herein by a process for treating finely divided silica fillers comprising contacting the filler, at a temperature of from 240°-310° C. for 4-16 hours while purging volatiles and water and maintaining a pressure of from 0 to about 15 psig, with a fluoroalkyl-functional diorganopolysiloxane treating agent, such as a hydrolyzate containing fluoroalkyl-functional cyclic polysiloxanes and low molecular weight diorganopolysiloxanes.
Preferred features will include preheating of the filler before contact with the treating agent.
The treated filler and curable fluorosilicone elastmeric compositions containing the fillers are also contemplated herein.
DETAILED DESCRIPTION OF THE INVENTION
The fillers treated by the process of the present invention are finely divided reinforcing fillers which may have free hydroxyl groups in the form of either Si-bonded functional groups or adsorbed moisture, depending on their method of preparation. The Si-bonded hydroxyl groups may also have been converted to other functional groups, such as alkoxy, in their manufacture.
These silica fillers are reinforcing fillers in contrast to other fillers of non-reinforcing, non-structure-forming type, such as titanium dioxide or calcium carbonate. Examples of such silica fillers may be found described in U.S. Pat. Nos. 2,541,137; 2,610,167 and 2,657,149, as well as French Pat Nos. 1,025,837 (issued 1953) and 1,090,566 (issued 1955). Such structure-causing fillers may be slightly acidic or alkaline (i.e., have pH's slightly below or above 7) depending upon the method of manufacture, and may be obtained through the aerosol-aerogel process, by fuming processes such as by the vapor phase burning of silicon tetrachloride or ethyl silicate, by precipitation means, etc. Commercially available fumed silicas include CAB-O-SIL® (Cabot Corp.) and AEROSIL® (Degussa, Inc.). Fumed silica is preferred.
The treating agents used in the practice of this invention are fluoroalkyl-functional polysiloxane fluids having a viscosity of from about 50-250 centipoise which may be formed from diorganodihalogensilanes that have been hydrolyzed to form a mixture of cyclics and short diorganopolysiloxane chains. The treating agent will be obtained from diorganodihalogensilanes of the formula R 1 RSiX 2 and R 2 SiX 2 , wherein R, R 1 and R 2 are representative of monovalent hydrocarbon radicals and halogenated monovalent hydrocarbon radicals that are well known as attachments to silicon atoms. At least the R 1 substituent contains three or more carbon atoms. R is the same as R 1 or is methyl, ethyl, vinyl or phenyl. R 1 is alkyl, such a propyl, butyl, hexyl, and the like, of from 3 to 8 carbon atoms; halogenated alkyl, such as 3-chloropropyl, 4-chlorobutyl, 3-fluorophenyl, 3,3-difluoropropyl, 3,3,3-trifluoropropyl, and the like of from 3 to 8 carbon atoms, or cycloalkyl of from 4 to 8 carbon atoms, such as cyclopentyl, cylcohexyl, cycloheptyl, and the like. Preferably, R 1 is a substituted alkyl group such as, --CH 2 CH 2 R 3 , wherein R 3 is perfluoroalkyl of from 1 to 6 carbon atoms, such as perfluoromethyl, perfluoroethyl, perfluorohexyl, and the like. Most preferably, R 1 is 3,3,3-trifluoropropyl, R is methyl or ethyl, and R 2 is methyl or ethyl, the latter two most preferably being methyl. X in the above formulae is halogen, such as chlorine or bromine, and preferably, chlorine. Such diorganodichlorosilanes, at a purity of at least 99% by weight, are added to water at room temperature, e.g., 29°-25° C. to provide from 2 to 10 moles of water per mole of the diorganodihalogensilane. In the most preferred case, after the diorganodihalogensilanes have been added to water, the mixture will contain about 20% by weight HCl. The hydrolysis may optionally be carried out in the presence of a water-immiscible solvent such as, for example, toluene, xylene, benzene, and the like. The use of a solvent facilitates the separation of the hydrolyzate from the aqueous acid solution. Where a water-immiscible organic solvent is used, it is preferably added to the water prior to the addition of the diorganodihalogensilanes. The diorganodihalogensilanes, preferably at 99+% purity, are added to the water during 1/2 hour to 2 hours with agitation. The hydrolyzate may be neutralized with a mild base, such as sodium bicarbonate. The hydrolyzate product contains mostly cyclic polysiloxanes of from 3 silicon atoms to 10 silicon atoms and low molecular weight linear silanol end-stopped diorganopolysiloxanes. The cyclic polysiloxane entities will have from 3-10 siloxy units, some of the larger ring structures arising from reformation of cyclic monomer starting materials; the linear entities will have varying block lengths, with the average degree of polymerization being about 5. They are typically fluid polymers having a low molecular weight, usually under 1000. See, for example, U.S. Pat. Nos. 2,737,506 (Hurd et al.), 3,937,684 (Razzano) and 4,341,888 (Razzano), all incorporated by reference. The fluoroalkyl-functional diorganopolysiloxanes thus formed are low viscosity fluids which are easier and safer to work with than the cyclic monomers.
To obtain the treated silica fillers of the invention, the filler is heated in the presence of the fluoroalkyl-functional polysiloxane treating agent at a temperature of from 240°-310° C. for 4-16 hours, at 0-15 psig pressure, while removing liberated volatiles (e.g., water, cyclics). Preferably, the silica filler will be contacted with the fluoroalkyl-diorganopolysiloxane treating agent over a temperature range of about 240° to about 260° C. for 4-8 hours at around one atmosphere (˜14.7 psig) pressure while removing volatiles, for example, by nitrogen purge. The resultant treated fillers will have a broad particle size distribution (˜73 wt. % <500μ; ˜60 wt. % >420μ) and surface area over the range of 150-160 m 2 /gm. When these fillers are used to reinforce fluorosilicone polymer gums at levels, for example, of about 25-35 parts per 100 of the total composition, curable fluorosilicone elastomers result which (when cured) have improved mechanical properties (especially tear strength and compression set). Preparation and handling of the filled compositions is also easier: Mixing of filler with polymer is fast and a good dispersion is obtained; the composition also releases cleanly from metal mixing equipment.
Most preferably, the raw (untreated) silica filler will be preheated in a sealed system for 4-30 hours (more preferably 4-20 hours) at a temperature of 240°-310° C. (preferably about 270° C.), then contacted with the fluoroalkyl-functional diorganopolysiloxane treating agent hydrolyzate while maintaining a sealed, fluidized system, and heated 4-16 hours longer (more preferably 8-10 hours) at 270°-310° C. while maintaining one atmosphere gauge pressure. This results in treated filler with a somewhat narrower particle size distribution (˜85 wt. % <500μ; ˜70 Wt. % >420μ).
Preheating the silica filler in a closed system is believed to promote a reversible surface condensation which reduces the number of free hydroxyl groups on the surface of the silica particles. The condensation also increases particle size, leading to a loss of surface area (˜149-160 m 2 /gm. as compared to 200-300 m 2 /gm. in untreated silica). The decreased surface area is believed to provide higher flourine content after treatment.
Prolonged preheating of the filler (e.g., >30 hours) results in particles which are too large, with insufficient hydroxyl functionality available for reaction with the treating agent. Treatment at pressures beyond about 15 psig or in a hydrous environment decreases the layering of fluoroalkyl-functional diorganopolysiloxane treating agent on the particle surface, which is a desirable characteristic of the treatment of the present invention. This decrease is believed to be due to some form of chain stopping.
The treated silica fillers prepared according to the present invention may be used in any heat- or room temperature-curable silicone rubber system or in any manner that finely divided silica fillers are commonly used in the art; but because the treated fillers disclosed herein have shown a compatability with fluorosilicone gums, leading to the unexpected processing improvements already discussed, use in fluorosilicone elastomer compositions, such as disclosed in U.S. Pat. No. 3,179,619 (Brown), U.S. Pat. No. 4,029,629 (Jeram) and U.S. Application Ser. No. 253,282, filed Apr. 9, 1981, now abandoned in favor of Ser. No. 443,545, filed Nov. 22, 1982 (all incorporated by reference), is especially contemplated.
The amount of treated silica filler used in combination with curable (vulcanizable) organopolysiloxane elastomer compositions may be varied within wide limits, for instance, from 10 to 100 weight percent of the filler based on the weight of the curable organopolysiloxane elastomer. The exact amount of filler used will depend on such factors as, for example, the intended application of the cured elastomer composition, the density of the silica filler employed, the type or organopolysiloxane elastomer employed, etc. By way of illustration, when curable fluorosilicone polymer gums are used, reinforcing with about 19-25 weight percent of the treated filler disclosed herein has resulted in marked improvement in tear strength and compression set. Judicious selection of materials and simple experimentation is contemplated to achieve optimal performance for a given situation.
Other fillers may of course be used in conjunction with the treated silica herein. These include, for example, untreated silica filler, titanium dioxide, lithopone, zinc oxide, zirconium silicate, iron oxide, diatomacious earth, finely divided sand, calcium carbonate, etc.
All patents and applications mentioned above are hereby incorporated by reference.
In order that persons skilled in the art may better understand how to practice the present invention, the following examples are offered by way of illustration and not by way of limitation.
EXAMPLES 1-5
Four treated silica filler compounds were prepared as follows:
______________________________________ 1 2 3 4______________________________________ COMPOSITIONsilica filler* 900 900 900 1000(lbs.)hydrolyzate** 220 220 220 250(lbs.)weight per- 19.6 19.6 19.6 20cent chargepreheating at 20 4 -- --270° C. (hrs.)treating >270° C./ >270° C./ >270° C./ 240° C./conditions 8 hrs. 8 hrs. 8 hrs. 8 hrs.pressure 15 psig 15 psig 15 psig 0 psig PRODUCTbulk density 0.089 0.095 0.118 0.25(gm/cc)weight per- 17.32 16.84 15.89 --cent treatingagent______________________________________ *CAB-O-SIL ® MS-7; Cabot Corporation **hydrolyzed 3,3,3trifluoropropylmethyldichlorosilane, containing cyclic polysiloxanes and low molecular weight linear silanol endstopped polysiloxanes
A fluorosilicone elastomer composition was prepared from 100 parts by weight fluorosilicone polymer, 3.0 parts by weight of a PDMS diol process aid: HO--(--Si(Me) 2 O--) 5 --H, 1.0 parts by weight of a PDMS process aid, 0.25 parts of (Me 2 ViSi) 2 NH, 0.65 parts by weight cerium hydroxide, and 0.8 parts by weight of 2,5-dimethyl-2,5-di-t-butylperoxyhexane. Treated filler compounds 1-4 were combined with the fluorosilicone elastomer compositions to make six test compositions. The six samples (designated A-F) were press cured fifteen minutes at 350° F. and post baked four hours at 400° F. to yield fluorosilicone rubbers with the following properties:
______________________________________ A B C D E F______________________________________ TEST COMPOSITIONSfiller used 1 1 2 3 4 4filler loading (parts 34 33 34 34 26 33per 100 of polymer) RUBBER PROPERTIESShore A 43 39 41 43 36 46Tensile Strength (psi) 1420 1205 1525 1505 1696 1130Elongation (%) 610 650 620 600 640 520Tear Strength, Die B 210 200 180 210 190 170(ppi)Bashore 21 20 19 18 -- 21Compression Set, 13.4 19.0 16.5 28.4 18.9 40.922 hours at 350° F.Specif. Gravity 1.424 1.417 1.422 1.426 -- 1.415______________________________________
Obviously, many variations will suggest themselves to those skilled in this art in light of the above, detailed description. All such modifications are within the intended scope of the appended claims. | A treatment for finely divided silica reinforcing fillers is provided which comprises heating the silica filler in the presence of a fluoroalkyl-functional diorganopolysiloxane treating agent. The treated fillers are especially compatible with fluorosilicone gums, and fluorosilicone rubbers made using said fillers exhibit improved mechanical properties, especially tear strength and compression set. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention concerns a method for regulating the indoor climate in
[0003] at least one room in a building, comprising:
[0004] at least one first unit configured to supply energy from an energy source to the room;
[0005] at least one second unit connected to the first unit and controlling the energy supply from the first unit based on at least one measured temperature, where control of the energy supply from the first unit is performed on the basis of on one or more sets of parameters;
[0006] at least one third central unit configured to communicate with the second unit, wherein the method includes the following steps
[0007] the third unit generates the set of parameters based on one or more sets of data describing the external, ambient conditions that influence the indoor climate, for example meteorological data for a geographical area in which the first unit is located.
[0008] 2. Description of Related Art
[0009] The present invention also concerns a window, including:
[0010] at least one window pane including one or more glass panes made of a transparent material;
[0011] at least one window frame in which the window pane is disposed;
[0012] at least one temperature sensor arranged at the periphery of the window pane;
[0013] an electric circuit connected to the temperature sensor and which is configured to generate a control signal when the measured temperature from the temperature sensor is equal to or greater than at least one reference temperature, and wherein the electric circuit is configured such that it can be connected to means that are configured to regulate the indoor climate in a room in which the window is located.
[0014] Presently there is an increased focus on energy consumption in houses in connection with new construction and with renovation of existing houses. Today there are greater demands on the insulating ability in new houses and on energy optimisation of existing houses, in particular thermal loss through walls and doors/windows, as well as control of the total energy consumption in the houses.
[0015] Different systems (also called building management systems) for controlling and monitoring the energy consumption in the building, including temperature control, are described in the literature.
[0016] JP 10184236 A discloses a system for controlling the indoor temperature in houses which by means of a skylight including an LCD layer and an outdoor temperature sensor regulates the amount of incident light through the window. The temperature sensor is connected to a controller which based on the measured temperature regulates the voltage applied on the electrodes connected to the LCD layer, whereby the light transmittance of the window is regulated and the temperature rise in the room is reduced.
[0017] The system has the disadvantage that the temperature is measured outside and not inside the room whereby the temperature sensor is heated more quickly than the room. The control of the LCD layer is thereby dependent on the incident angle and direction of the light for performing correct control of the temperature in the room. Thus there is a risk that the LCD layer is activated too early or too late in relation to the desired temperature in the room.
[0018] JP 2161091 A discloses a similar system which uses a temperature sensor disposed in the room and a temperature regulator for regulating light transmittance in a skylight. The controller compares the measured temperature with a reference temperature and activates a voltage regulator connected to the LCD layer in the window when the temperature exceeds the reference temperature.
[0019] The system has the disadvantage that the temperature sensor measures a point in the room, typically close to the floor or at a wall, implying that the temperature may vary at other points in the room if the case is a relatively large or long room. If the temperature sensor is not disposed at an optimal location in the room the system will furthermore not perform a correct regulation of the temperature in the room.
[0020] US 2005/0166495 A1 discloses a window with a temperature sensor disposed at the internal side of the window where the sensor is connected to a controller integrated in the window frame. The controller activates a heating wire arranged along the periphery of the interspace between the glass panes if the measured temperature exceeds a pre-set reference temperature. U.S. Pat. No. 6,369,935 B1 discloses a window with an electrochromic layer arranged between two glass layers. The electrodes from the electrochromic layer is connected to a separate controller disposed close to the window and controlling the light transmission through the electrochromic layer by means of a temperature sensor integrated in the spacer or in the glue joint close to one of the glass panes.
[0021] By using a sensor disposed at a single point on the window pane there is not provided a true indication of the temperature changes in the window or the incident light through the wind as the measured value will depend on the direction and angle of the sunlight. Also, the system will be slow to react to changes in temperature as the reaction time will depend on the position of the sensor in relation to the light incidence.
[0022] Various solutions for control and programming of the energy supply to a room in a building are described in the literature in addition to the above mentioned solutions. An electronic room thermostat from the company Danfoss A/S is an example of such a solution where the room thermostat wirelessly controls the energy supply from a radiator based on a room temperature measured by a temperature sensor in the room thermostat. The room thermostat can control the temperature in the room based on various programmable settings. Another example of such a solution from the same company is a touch screen or control unit in a building management system which is wirelessly connected to one or more radiator thermostats located in different rooms, where the setting of each thermostat can be programmed/controlled by means of the control unit.
[0023] GB 2153554 A discloses a control method for regulating the temperature inside a building having a central heating system controlled by a central controller. The controller controls the activation of the central heating system based on the meteorological forecast data. EP 1715254 A1 discloses a similar control method where the controller controls a heating system integrated in the floor of the room based on the meteorological forecast data.
[0024] All of the above solutions describe solutions in which the control of energy supply is performed based on a number of manually entered parameters, such as reference temperatures and time intervals. This manual programming of the radiator thermostats is both tedious and time-consuming. None of the above mentioned solutions indicate a solution wherein control of the energy supply is adapted to external conditions from outside that influence the energy supply, such as the weather in the geographical area in question or the compass direction in which the thermostat and the associated window are facing.
SUMMARY OF THE INVENTION
[0025] The object of the present invention is to provide a window that intends to solve the problems of the prior art in a more simple and thereby less costly way.
[0026] The object of the present invention is to provide a window which can be implemented as an integrated solution without using external apparatuses.
[0027] The object of the present invention is to provide a window which registers temperature at the spot where the temperature fluctuations are the greatest in a window.
[0028] The object of the present invention is to provide a window which has a short reaction time to measured changes in temperature.
[0029] The object of the present invention is to provide a control of an intelligent window wherein the control is adapted to the position of the window.
[0030] The present invention provides for solving the problems of the prior art by providing a method for regulating the indoor climate in at least one room in a building, characterised in that
[0031] the geographical position of the first unit is determined and transmitted to the third unit, based on which position the third unit determines the sets of parameters.
[0032] Control and programming of the energy supplying unit can hereby be adapted to outdoor conditions influencing the indoor climate, e.g. the geographical area in which the unit is located. Previously, control has only been performed in relation to indoor parameters in the indoor climate, such as the type of room and the room temperature. The central unit may advantageously be a central server which can communicate with an external server or database including one or more sets of historical meteorological data for one or more geographical areas. The meteorological data can include information about temperature conditions, wind conditions, precipitation, air pressure, hours of sunshine or other climatic data and/or observation data for the geographical areas. By using meteorological data, the programmable parameters according to which the energy supplying unit is controlled are adjusted to the weather in the area in question. Several parameters can hereby be adjusted automatically whereby the need for manual programming and adjustment of the parameters is reduced. The method can advantageously be used for controlling and programming an intelligent window including means for regulating the incidence of light from energy sources such as the sun and/or lighting units, wherein the means are controlled on the basis of the generated parameters. The method can furthermore be used for programming and controlling other energy sources such as heating units, ventilation units, cooling units and/or circulation units intended for supplying energy to the air or to circulate/change the air in the room or building, wherein the units are controlled by a thermostat, e.g. an electric thermostat or an intelligent window with built-in thermostat function.
[0033] The geographical position of the window can hereby be determined and transmitted to the central server which then can retrieve the meteorological data for the area in question. The geographical position of the window can be determined by means of a position module in the window in the form of a GPS module or a module configured to triangulate the radio signals from two or three antennas/sending masts. The geographical position can be determined by means of the functions in a mobile communication unit in the form of a mobile phone, a PDA, a tablet or other mobile communication unit, e.g. by means of a GPS module or other position-based service. The mobile communication unit can communicate with the central server via a mobile data network and/or with the window via a local data network.
[0034] In an embodiment of the invention, the compass direction of the first unit is determined and transmitted to the third unit, based on which compass direction the third unit determines the sets of parameters.
[0035] The compass direction of the window is determined and transmitted to the central server which then can adjust the parameters according to whether the window is facing south, north, west, east or other compass direction. The compass direction can be determined by means of a directional module in the window including a digital compass with two or three magnetic field sensors or a GPS receiver with two or three antennas. The compass direction can be determined by means of the functions in the mobile communication unit, e.g. by means of the GPS module, an electronic compass in the phone or a compass service. The position and the compass direction of the window can be combined with the meteorological data in a processor in the server where the server generates one or more sets of parameters by which the functions in the window are controlled during normal operation. The control of the window can hereby be optimised to its position and the weather in the geographical area, implying that more free energy can be conducted/supplied into the room from outside (from the sun) and the amount of energy from energy sources in the room can be reduced.
[0036] Geometrical data in the form of a plan drawing of the building and/or the external geometrical shape of the building can be stored in central server. The geometrical data can be used for determining the sets of parameters by which the window is controlled. Hereby, the surrounding building components, such as eaves, other windows, projections on the building or other relevant conditions, can be taken into account. Other data such as air quality (degassing level, CO 2 concentration, smog, ozone etc.), room type (office, canteen, classroom etc.), light conditions (path of sun relative to the room/window) and/or choice of material (U/G/L/Psi-values for the window and the wall around the window) can be stored in the server and used for determining the parameters. All the data can be used for determining the parameters stored on the server so that only the sets of parameters are transferred to the window. The parameters can be determined from any type of data or a combination thereof. The loss of energy in the building/room and external conditions such as smog and the like can hereby be taken into account, thus achieving a better and more optimal control of the energy supply.
[0037] In an embodiment according to the invention, the second unit communicates with a mobile communication unit or local control unit which in turn communicates with the third unit.
[0038] The window can hereby communicate with the central server via a mobile data network or via a wireless internet connection in the mobile communication unit. This can take place either instead of or as a supplement to the directly wired or wireless connection between the window and the central server. The mobile communication unit may again communicate with the window via a local data network generated by either the communication module in the window or a communication module in the unit. The communication module in the window can be designed as a WIFI module, a WLAN module, a Bluetooth module, an IR module, an NFC module, or another wireless communication module. The position module and the direction module in the window can be omitted so that the number of components in the window and the production costs are reduced. The window may instead communicate with a local control unit in the form of an operating panel including at least one display, or in the form of an external controller in a building management system via the local data network. The controller/operating panel may in turn communicate with the central server via a wired or wireless internet connection. The functions in the window can hereby be controlled by means of an operating panel provided on e.g. a wall, or communicate with a building management system which can transmit and receive data from the window and possibly control the window.
[0039] In an embodiment according to the invention, the energy supply from the first unit is controlled by means of an application configured to run on the mobile communication unit.
[0040] The functions in the window can hereby be controlled by means of an application in the mobile phone where the application can be downloaded on the mobile phone via a homepage, e.g. stored on the central server. The application may communicate with the window by means of the wireless communication in the window. The application can be designed to control the functions in the window by means of one or more graphic user interfaces that may be arranged in the application or managed by the server. One or more of the graphic user interfaces can be designed to visually indicate one or more of the measurements performed in the window via text or graphics. The shown measurements can be the temperature T m and/or T r , the air pressure, light index or another measurement. The user can perform adjustment of one or more parameters by which the window is controlled. The operating panel in the window can hereby be omitted so that the number of components in the window and the production costs are further reduced.
[0041] In an embodiment according to the invention, the first unit is a window where one or more means regulating the amount of incoming light through the window is/are arranged in or close to the window and that the second unit is an electric circuit measuring at least one temperature and controlling the means based on the set of parameters.
[0042] The described method can hereby be used for controlling an intelligent window based on the meteorological data characterising the weather in the geographical area in which the window is located. Moreover, control of light incidence through the window pane can be adapted to the position of the window on the building. The supply of free and green energy from the ambient surroundings (sun) can hereby be controlled and optimised such that the window remains transparent/translucent for a longer time whereby the amount of energy from the energy sources in the room can be reduced.
[0043] In an embodiment according to the invention, the first unit is a heating unit provided in the room, and that the second unit is a window comprising a control unit controlling the amount of energy supplied from the heating unit based on the set of parameters.
[0044] The present invention intends to solve the problems of the prior art by providing a window which is characterised in
[0045] that the temperature sensor is designed as a line sensor detecting the temperature along a line along at least part of the periphery of the window pane, and that means are configured to regulate the indoor climate as described above.
[0046] Hereby is provided a window that measures the temperature at the point on the window where the heat flow and thereby the temperature fluctuations in the window are the greatest. Thereby a more accurate detection of the temperature in the window can be performed whereby a better regulation of the light incidence, the temperature and thereby the energy supply to the room can be performed. Moreover, there is provided a window which functions as an independent unit which does not need to be connected to other external units, such as thermostats, temperature sensors or controllers, in order to measure and regulate the temperature in the room. In its simplest form, the window can function as a window with integrated thermostatic function. The window can include two, three, four or more panes arranged in a window frame wherein the panes are separated by a number of intermediate frame members. The temperature sensor can be arranged along one or more of the panes.
[0047] The temperature can hereby be measured along the entire periphery of the pane or a predetermined part thereof such that the temperature sensor also can detect when the sunlight only falls on part of the window. This provides that the window can detect the heat flow through the window irrespective of where the sunlight falls on the window; the window can hereby also detect even small heat flows. This implies that the window can regulate the light incidence or the temperature in the room as early when the sunlight starts to fall on the window and not just when the sunlight falls on the sensor. The window frame can advantageously be made of a material with high thermal conductivity so that the temperature sensor measures across a large temperature range and more easily can detect the temperature fluctuations. By measuring the temperature with a single sensor extending along the periphery/circumference of the window pane, an expression (mean value) for the temperature as perceived over the entire window can be determined.
[0048] In a specific embodiment according to the invention, at least one first temperature sensor is arranged along a first part of the periphery of the window pane, and one second temperature sensor is arranged along a second part of the periphery of the window pane, wherein both temperature sensors are connected to the electric circuit.
[0049] The window can hereby be divided into a number of sections where the temperature in each section is determined by means of a sensor extending along a specific section of the window. The temperature in the window can then be determined from the temperature in the different sections. Four sensors extending along the periphery of the top member, bottom member and side members, respectively, can be arranged in the window, where an expression of the temperature in the window can be determined as the average of the four measured values. Alternatively, one or two sensors can be arranged along one of the sections and extend a length in over another of the sections.
[0050] In an embodiment according to the invention, the temperature sensor is disposed in a first sealing in the window pane or in a joint arranged between the window pane and the window frame. In a particular embodiment, at least one second temperature sensor is disposed in at least one second sealing.
[0051] The control unit can hereby determine which way the heat flows through the window whereby the heat loss and the heat supply, respectively, can be determined. A more optimal regulation and control of the energy sources and the actuators in the room, such as the radiators, the floor heating and the ventilation in the room, can be performed. The heat loss and the heat supply can also be used for determining and optimising the energy consumption in the building. Moreover, it is possible to use the outermost or the innermost temperature sensor as a reference sensor, eliminating the need for another separate reference temperature sensor.
[0052] In an embodiment of the invention, the electric circuit includes a control unit configured to control an operation unit via the control signal, and wherein the operation unit is configured to regulate the indoor climate in a room in which the window is located.
[0053] The window can hereby be connected to an operation unit that regulates the indoor climate in the room based on measurements performed at the point where the temperature fluctuations are the greatest. Furthermore, the control unit can perform a stepwise/gradual regulation of the light incidence/energy supply as the temperature rises in the room; it is possible hereby to prevent too large variations in the temperature in the room. This allows seeing out of the window for a longer time simultaneously with the light incidence is attenuated. The operation units may advantageously be controlled on the basis of one or more sets of programmable parameters which are possibly adapted to the geographical location of the window and thereby the weather in the area in question, orientation of the window, the geometrical shape of the building and/or other data like air quality and type of room. The window can be used as a thermostat connected to an energy source provided in the room, e.g. a heating unit in the form of a radiator or heat exchanger, where the control unit in the window controls the amount of energy supplied from the energy source based on the generated parameters. The operation unit can be designed as a ventilation unit and/or cooling unit, e.g. disposed in the window frame where the opening/closing of the damper or activation of a valve is controlled by the control unit based on the temperature measurement and/or a CO 2 measurement. The air in the room can hereby be replaced by fresh air from outside. The control unit can be connected to a circulation unit and/or lighting unit wherein the circulation of the air in the room or control of the light is performed based on the generated parameters.
[0054] In a particular embodiment of the invention, the operation unit is mounted at or in the window frame and is connected to either a light transmitting layer arranged in the window pane or a sunshade connected to the window.
[0055] Hereby, the installation of the window can be simplified as it is not necessary to connect the window to an external control unit for controlling the light incidence or the temperature in the room. Moreover, the control unit and possibly the operation unit can be hidden inside the frame, e.g. via a removable cover, such that they do not interfere with the aesthetical appearance in the room. Also, the window can operate independently of other units as all electronics are mounted on or in the window frame. The window can thereby independently regulate the temperature or the light incidence based on input from own sensors arranged in or at the window.
[0056] In an embodiment of the invention, the controller is connected with an operating panel and/or a wireless communication module which is configured to communicate with an external apparatus or at least a second window.
[0057] The user can hereby perform a manual adjustment or control of the functions in the window, such as setting the reference temperature or choosing different program options. The operating panel can advantageously show the measured temperature or other parameters/options which the user then can select/adjust via one or more buttons/switches. Also, it is possible to control the window by means of the wireless connection, either via a remote control or a building management system. Together with a control signal, the measured temperature can advantageously be transmitted to the building system which determines how much natural/free energy is supplied to the room from outside, and possibly subsequently adjust the amount of energy transferred from the energy sources to the energy sources in the room. It is hereby possible to reduce the total energy consumption in the room and thereby in the building.
[0058] A first communication module can be configured to communicate with a central server via a wireless or wired internet connection. A second communication module can be configured to communicate with a building management system and/or at least a second intelligent window. The window can hereby operate as a master unit controlling at least a second intelligent window which can function as a slave unit. The window can include a position module in the form of a GPS module connected to the electric circuit. The window can include a direction module in the form of a digital compass that may include two or three magnetic field sensors or a GPS receiver with two or three antennas. The direction module can alternatively be integrated or built into the position module. The position and the compass direction of the intelligent window can advantageously be used for determining the parameters by which the intelligent window is controlled.
[0059] In an embodiment of the invention, a temperature regulating element is arranged at the periphery of the window and in direct or indirect thermal contact with a joint arranged between the window and the window frame. In a particular embodiment of the invention, the temperature sensor and the temperature regulating element are designed as one and the same element.
[0060] The temperature regulating element can hereby be used for preventing condensation formation at the inner side of the window by heating the window frame and thereby the periphery of the window as well, e.g. to 20° C. or to a temperature over the dewpoint temperature. Activation of the temperature regulating element may advantageously be combined with measurements from other sensors, e.g. an external or internal temperature sensor, air humidity sensors or similar.
[0061] In an embodiment of the invention, at least one other type of sensor, such as a light sensor, an air pressure gauge and/or a vibration meter, is arranged in or at the periphery of the window pane and connected to the electric circuit.
[0062] The electric circuit may advantageously be connected to at least one second type of sensor disposed at the outer or inner side of the pane/window. A light sensor in the form of a LUX-sensor or a PIR sensor can be connected to the electric circuit, and the window can hereby remain transparent, even on an overcast day with high temperatures or as long as daylight persists. An air pressure gauge in the form of a barometer can be connected to the electric circuit so that the window can remain transparent even on days with thunder where high temperatures are experienced simultaneously with an overcast sky, or by the encounter between a low pressure and a high pressure. At least one vibration sensor in the form of a strain gauge, a piezoelement, a shock sensor or an accelerometer can be connected to the electric circuit. Input from this sensor can hereby be used in connection with burglar alarm or in connection with a condition monitoring of the window. If the window pane is smashed/destroyed it can, for example, be detected as a sudden and distinctive change in the measured parameters. This condition monitoring can be used for performing a service life estimation, e.g. based on expansions and contraction based on the measured values as the latter can provide an indication as to when it is necessary to replace the assembly. A CO 2 meter can be arranged in the window frame for ventilating the air in the room by means of a ventilation unit.
[0063] The invention is described in the following with reference to the drawing, wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
[0064] FIG. 1 shows a simplified layout of the window according to an embodiment of the invention;
[0065] FIG. 2 shows a cross-section of a first embodiment of the invention shown on FIG. 1 ;
[0066] FIG. 3 shows a cross-section of a second embodiment of the invention shown on FIG. 1 ;
[0067] FIG. 4 shows a simplified layout of the electric circuit according to an embodiment of the invention; and
[0068] FIG. 5 shows an example embodiment of the control and programming of the window according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0069] In the explanation of the Figures, identical or corresponding elements will be provided with the same designations in different Figures. Therefore, no explanation of all details will be given in connection with each single Figure/embodiment.
[0070] By the term “energy source” is meant any kind of energy source or unit configured to the active or passive transfer of positive energy for heating or negative energy for cooling the room or building. The term “energy source” also includes a unit configured to circulate the air internally of the room or to mix the air with air from another room or from outside wherein the energy from the warm air is transferred to the cold air. By the term “energy” is meant any kind of energy occurring in a room or a building, e.g. thermal energy in the form of heat, light energy in the form of artificial light and sunlight, radiation energy in the form of heat radiation, and other forms of energy.
[0071] FIG. 1 shows a simple layout of the window according to the invention including at least one window pane 1 mounted in at least one window frame 2 . The window pane can include one, two, three or more layers 8 , 9 in the form of glass panes made of a transparent and approximately rigid material such as glass, plexiglass or other suited material.
[0072] The window frame 2 in the shown embodiment is designed as a four-sided window including a top member 3 and a bottom member 4 connected with two side members 5 , 6 . The window frame 2 can be made of aluminium, wood, PVC, composite or other suited material and can be designed as a hollow or solid window frame. The window pane 1 can be divided into one or more sections (not shown) where the glass panes 8 , 9 in the individual sections may be divided by an intermediate frame member connection to at least one of the members 3 , 4 , 5 , 6 .
[0073] FIG. 2 shows a cross-section of a first embodiment according to the invention wherein the window pane 1 is connected to an end face 2 a on the window frame 2 via a joint 7 . The joint 7 can be a glue joint, a rubber joint or other suitable joint configured to retain the window pane 1 in the window frame 2 . In this embodiment, the window frame 2 is designed as a narrow window frame. The window pane 1 can include two, three or more glass panes 8 , 9 separated by a number of spacers 10 such that the glass panes 8 , 9 and the spacers 10 together form a cavity 11 . The cavity 11 along the edge of the glass panes 8 , 9 can be sealed by means of silicone, elastic joint filler or other suitable sealing material 12 . The cavity 11 can be filled with a gas such as krypton, argon, air or other suitable gas.
[0074] A layer of light-transmitting material 13 such as electrochrome, fluid crystals (called LCD), thermochrome, window film, sunfilm, UV-film, or other suitable material can be provided at the inner side 8 a of the glass pane 8 . Alternatively, the light transmitting material 13 can be provided at the outer side 9 b of the glass pane 9 . The light transmitting layer 13 can be designed as one whole section or several sections that all can be connected to an operation unit 14 . The light transmitting layer 13 can be configured such that its light transmittance (called LT) and/or other energy transmittance (called G-value) is changed at a given temperature, voltage or other type of energy supplied via the operation unit 14 . Alternatively, at the outer side of the window pane 1 there may be arranged a sunshade (not shown) in the form of a Venetian blind, lamellae, panels, a curtain, an awning or other suitable arrangement. The sunshade can be connected to the operation unit 14 which can activate the sunshade and/or operate the functions in it.
[0075] The operation unit 14 can be configured to activate the light transmitting layer 13 and/or the sunshade, e.g. by changing the polarity of the material or by supplying energy in the form of heat or a voltage. The operation unit 14 can be mounted on or in the window frame 2 , preferably in one side member 5 , 6 . The window frame 2 can include a cutout 15 or a closed housing (not shown) in one side face 16 in which the electric circuit 17 is arranged. The operation unit 14 can be connected to the electric circuit 17 and controlled by means of the electric circuit 17 . The operation unit 14 can be arranged in the cutout 15 together with the electric circuit 17 .
[0076] The electric circuit 17 includes a control unit 18 which may include a microprocessor which in turn is connected to at least one temperature sensor 19 arranged along the periphery of the window 1 . The control unit 18 can be configured to compare the measured temperature T m from the temperature sensor 19 with at least one reference temperature T r . If the measured temperature T m is equal to or greater, the control unit 18 generates a control signal that activates the operation unit 14 . The reference temperature T r can be measured by means of at least one secondary temperature sensor (not shown) which may be disposed inside the room, outside close to the window and/or in the cutout 15 together with the electric circuit 17 .
[0077] In a particular embodiment, the control unit 18 can compare the measured temperature T m with a number of reference temperatures T r on the basis of which the operation unit 14 can perform a stepwise/gradual operation of the light transmitting layer 13 and/or the sunshade. The stepwise/gradual operation is defined as being a percentage graduation of the maximum energy supply or light/energy transmittance, e.g. 0%, 50%, 100% or any other graduation there between.
[0078] In a particular embodiment there are two, three or more temperature sensors 19 , 20 arranged at the periphery of the window pane 1 . The temperature sensors 19 , 20 are disposed in each their sealing 12 between the individual glass panes 8 , 9 . Alternatively, one temperature sensor 19 can be provided in the joint 7 , 22 between the window pane 1 and the window frame 2 while the other temperature sensors 20 can be distributed in the sealing 12 between the individual glass panes 8 , 9 .
[0079] FIG. 3 is a cross-section of a second embodiment according to the invention which differs from the cross-section in FIG. 2 in that the pane 1 is disposed in cutout 21 in the form of rabbet on the window frame 2 . In this embodiment, the window frame 2 is designed as a wide window frame in which the rabbet can be formed along the inner side face 16 and the end face 2 a of the window frame 2 .
[0080] In this embodiment, the window pane 1 can be provided on a number of spacer blocks (not shown) in the bottom member 4 , wherein along the periphery of the inner side 9 a of the window pane 1 there may be provided a second joint 22 in the form of a rubber band, an elastic joint filler or other suitable joint. The window pane 1 can be retained in the rabbet 21 by means of an edge profile 23 which can be disposed at the outer side 8 b of the window pane 1 and can include a joint (not shown) facing the joint 22 .
[0081] FIG. 4 shows a simplified layout of the electric circuit 16 according to an embodiment of the invention.
[0082] A power source 24 in the form of a solar cell arrangement can drive the electric circuit 17 . An accumulator (not shown) in the form of a rechargeable battery can be connected to the power source. The solar cell arrangement can be disposed at the outer side of the top member 3 or the bottom member 4 and be connected to the electric circuit 17 via a set of wires concealed in the window frame 2 . Alternatively, the power source 24 can be designed as a power supply circuit which can be connected to the electricity network (not shown).
[0083] One or more temperature sensors 19 , 20 can be arranged in or at the periphery of the window pane 1 , preferably in the joint 7 , 22 and/or in the sealing 12 . By the term “periphery” is meant the outermost edge on the window pane 1 between the side faces 8 a , 8 b or the side faces 9 a , 9 b and up to 5 cm in on the side face 8 a , 8 b , 9 a , 9 b . By the term “at the periphery” is meant either in direct contact with the periphery or up to 17 mm therefrom. In a particular embodiment, the temperature sensor 19 , 20 is provided in direct contact with the internal side face 8 a , 9 a and/or the external side face 8 b , 9 b on at least one of the glass panes 8 , 9 .
[0084] In a simple embodiment, the temperature sensor 19 , 20 is designed as a line sensor configured to measure the temperature as seen along the whole line. By the term “line sensor” is meant a number of sensors that measure the temperature in a series of points along the entire length of the line, or a sensor which has an elongated measurement area corresponding to the length of the line, and wherein is measured a temperature dependent parameter, e.g. the resistance/capacity/inductance in a conductor or similar.
[0085] The control unit 18 can be connected to an operating panel 25 that includes a display/gauge and a number of buttons/switches disposed at the side face 2 b in the window frame 2 . The operating panel 25 can alternatively be hidden behind a removable cover on the window frame 2 .
[0086] At least one wireless communication module 26 can be connected to the control unit 18 whereby the control unit 18 can communicate wirelessly or wired with other intelligent windows and/or an external apparatus 27 . The external apparatus 27 can be a system configured to control and monitor the indoor climate in the building and/or monitor the energy consumption in the building, such as a building management system (BMS). The control system 18 can transmit the measured temperature T m and other status information to the external apparatus 27 , either periodically or upon request from the external apparatus 27 . The external apparatus 27 can transmit one or more control signals/requests to the control unit 18 based on which the control unit 18 can perform one or more actions and/or return one or more responses.
[0087] In a particular embodiment, the window can be configured as a master unit that communicates with a number of other windows (not shown) which can be configured as slave units. The slave units can have the same design as the master unit or include the components needed for performing the desired function or functions.
[0088] At least one temperature regulating element 28 can be arranged in or at the same joint 7 , 22 as the temperature sensor 19 , 20 . The temperature regulating element 28 can be configured to give off heat when the element 28 is powered by the power source 24 or an external power source (not shown). In a particular embodiment, the temperature sensor 19 , 20 and the temperature regulating element 28 are designed as one and the same element. This element can be connected to a multiplexer or an electrically controlled switch that may be controlled by the control unit 18 . The element can hereby be connected to the control unit 18 and to the power source 24 , or to an external power source possibly via a connector (not shown). Alternatively, at the inner side 9 a of the innermost glass pane 9 there may be provided a temperature regulating layer (not shown) controlled by the control unit 18 .
[0089] The temperature regulating element 28 and/or the temperature sensor 19 , 20 can be designed as a conductor in the form of an electric conducting wire which may be a twisted wire or a straight wire, insulated or uninsulated.
[0090] One or more types of sensors 29 , such as a vibration sensor, a humidity sensor or similar types of sensors, can be arranged at one or more points along the periphery of the window pane 1 . A light sensor, an air pressure gauge, or other type of sensor can be arranged on or in the window frame 2 , either at the inner side or the outer side. The control unit 18 can be connected to the sensors 29 via a set of wires or a bus which also can be connected to the temperature sensors 19 , 20 .
[0091] At least one position module (not shown) can be connected to the electric circuit and the control unit 18 . The position module can be configured to determine the position of the intelligent window based on GPS coordinates or by triangulation of radio signals. At least one direction module (not shown) can be connected to the electric circuit and the control unit 18 . The directional module can be configured to the compass direction of the intelligent window and can be provided as a digital compass with two or three magnetic field sensors, a GPS receiver with two or three antennas, or similar.
[0092] FIG. 5 shows an example embodiment of the control and programming of an intelligent window. The system can include at least one intelligent window 30 as described above which can communicate directly with at least one central server 31 by means of the communication module 26 via a wireless or wired data network. The server 31 can comprise a communication module configured to communicate with the window 30 via the data network. Alternatively, the window 30 can communicate with the server 31 via at least one mobile communication unit 32 in the form of a mobile phone, a PDA, a table or another mobile communication unit. The server 31 can communicate with the communication unit 32 via a mobile data network, e.g. from a phone operator or a wired connection. The communication unit 32 can in turn communicate with the communication module 26 in the window 30 via a second wireless data network, or a wired connection. The communication module 26 can be designed as a WIFI module, a WLAN module, a Bluetooth module, an IR module, an NFC module, or another dedicated communication module which can communicate with a corresponding module in the communication unit 32 .
[0093] The central server 31 can be configured to communicate with at least one other server or database 33 via a wired or wireless connection. The server/database 33 can include one or more sets or meteorological data for one or more geographical areas. The meteorological data can include information about temperature conditions, wind conditions, precipitation, air pressure, hours of sunshine or other climatic data and/or observation data. The central server 31 can be configured to receive one or more parameters from the window 30 via the communication module 26 and/or the communication unit 32 . The server 31 can be configured to combine these parameters with the received meteorological data and generate a set of parameters by which the window 30 is controlled during normal operation. The set of parameters can be transmitted directly to the window 30 via the wireless connection with the window 30 or via the mobile communication unit 32 .
[0094] At setup and installation of the window 30 , the compass direction of the window 30 can be determined by means of the direction module in the window 30 , and the position of the window 30 can be determined by means of the position module. The operating panel 25 can be used for activating and interacting with the two modules. Alternatively, the compass direction can be determined by means of an external unit and entered via the operating panel 25 . The compass direction and the position of the window 30 are then transmitted to the central server 31 where the received data are stored in a memory in the server 31 . The server 31 then transmits a request comprising an indication of the position of the window 30 to the server/database 33 which returns the meteorological data for the geographical area in which the window 30 is located. The server 31 then generates one or more sets of parameters which are used for controlling the functions in the window 30 during normal operation, based on the compass direction and the position of the window 30 and the meteorological data. The generated parameters are then transmitted to the window 30 and stored in a memory in the window 30 . The parameters can alternatively be generated on the basis of a set of predetermined parameters stored in the memory on the server 31 and which are adapted to the position and compass direction of the window 30 and the meteorological data.
[0095] In a second embodiment, the compass direction and the position of the window 30 can be determined by means of the functions in the communication unit 32 . The communication unit 32 is disposed on or close to the window 30 after which the position and the compass direction are determined by means of the communication unit 32 . The data are then transmitted to the server 31 which generates a set of parameters based on which the window 30 is controlled during normal operation. The generated parameters are then transmitted back to the communication unit 32 and on to the window 30 via a wireless communication module in the communication unit 32 . The position module and the direction module in the window 30 can be omitted hereby, and the communication module 26 can be adapted to communicate with the communication unit 32 by means of a local wireless data network.
[0096] In a third embodiment, control of the window 30 can be performed by means of an application configured to run on the communication unit 32 . The application can be configured to communicate with the server 31 via a wireless communication module in the communication unit 32 . The application can be configured to communicate with the window 30 by means of the wireless communication module 26 in the window 30 . The application can be designed to control the functions in the window 30 by means of one or more graphic user interfaces. One or more of the graphic user interfaces can be designed to visually indicate (via text or graphics) one or more of the measurements performed in the window 30 , e.g. the temperatures T m , T r , air pressure, light index or other measurement. The user can control the functions in the window 30 by means of the application and possibly perform a change in one or more of the parameters by which the window 30 is controlled. The operating panel 25 can hereby be omitted. | The invention concerns a window including a window pane with one or more glass panes, a window frame in which the window pane is provided, at least one temperature sensor arranged in or at the periphery of the window pane, and an electric circuit connected to the temperature sensor mounted on or in the window frame. The electric circuit is configured to be connected to an operation unit which is configured to regulate the incident light through the window pane. The invention furthermore concerns a method for controlling a window wherein the electric circuit controls the means configured to regulate the incident light through the window pane based on a set of parameters. The parameters are determined on the basis of the orientation and geographical position of the window whereby the supply of free energy is optimised and the amount of energy supplied from energy sources in the room is reduced. In an embodiment the window can be controlled by means of an application configured to run on a mobile communication unit. | 4 |
CROSS REFERENCE TO RELATED APPLICATION
This is a continuation of U.S. application Ser. No. 08/603,162, U.S. Pat. No. 5,991,260 filed Feb. 20, 1996, the subject matter of which is incorporated by reference herein. The present invention relates to a disk cartridge, a disk cassette, a disk caddy, a disk half or a disk case for housing a disk-shaped recording medium such as an optical disk, and a disk device using the same.
BACKGROUND OF THE INVENTION
A compact disk (hereinafter, referred to as "CD") system, which has been standardized in the so-called "red book", the so-called "yellow book" or the like and in which information is recorded in a disk having a diameter of 120 mm, and which is used mainly for music information has been widely adopted. This system has an almost sufficient capacity for handling music information, but when recording video information as in a CD-ROM, its capacity becomes insufficient for an increased amount of information, thus resulting in insufficient recording time or degraded image quality. Attempts to deal with this problem includes, for example, a digital video disk (hereinafter referred to as "DVD") system and the like.
In the aforementioned CD system, the disk is mainly used on only one side or face for exclusive reproduction. Also, the disk is often handled in a bare state, and a tray loading system, in which the disk is mounted on a drawer-shaped tray coming out from a disk device, is mainly used because of its good operability. On the other hand, however, a disk cartridge, which is called a CD caddy, as described in Japanese Laid-Open Patent Application No. 63-153376 and in Japanese Laid-Open Patent Application No. 63-47472, capable of taking a disk out and in, is used, and a front loading system for inserting this disk cartridge into the device is also utilized.
In addition, in the aforementioned DVD system, the disk is used on both sides or faces for recording and/or reproduction. The disk tends to be housed in an exclusive cartridge primarily for protection from the standpoint of securing the reliability resulting from higher density recording.
Further, in contrast to the CD system, which is mainly used for exclusive reproduction, there has also been announced a PD (Phase-change Disk) system capable of rewriting, as described in Optical Disk System for Multimedia National Technical Report, Vol. 4, No. 6, December 1994, pgs. 129-136. In this PD system, the disk is used on one side for recording and/or reproduction. Also, the disk is housed in an exclusive cartridge from the standpoint of securing the reliability resulting from rewriting.
Disks for use with each system of the aforementioned CD, DVD and PD all have a diameter of 120 mm, and cartridges for each system described above are of nearly the same shape, having the same dimensions.
The problem to be solved by the present invention is to increase the capacity of the CD system or a disk system having nearly the same dimensions as the CD system, and the concept and technical problems for the disk cartridge and disk device using the same to deal with the problem are described below.
1) In order to take measures against scratching, dust and dirt resulting from higher density recording, a state in which a disk has been placed in a cartridge is supposed to be a standard. Even in the CD system, there is present a case called a "CD caddy" which is about 135 mm long, about 125 mm wide and about 8 mm thick, but this CD caddy is not used currently. Rather, the so-called tray loading system is mainly used.
2) Allowing both faces of the disk to be recorded. The CD is for one side recording and the capacity can be doubled by simple calculation.
3) Making a disk which is CD compatible and reproducible In a disk device using a new disk cartridge, its sales point is to make the existing CD compatible and reproducible. Accordingly, it is an indispensable condition to enable taking a disk in and out and having a disk for CD system within. However, the CD caddy is for one-side recording, and a clamper of the disk is attached on the side of the caddy case. The clamper is constructed to be on the side of the disk device because the new disk cartridge is of a both-face recording system. Thus, if the CD caddy is mounted to a disk device for the new disk cartridge, two clampers will interfere with each other. Therefore, it is necessary to prevent the CD caddy from being mounted to the disk device of the new disk cartridge.
4) Supply of the disk and disk cartridge at a low price. In order to reduce the price for general family usage, the disk cartridge including the disk device is required to be constructed at low cost.
Further, when increasing the capacity as described above, the mixed existence of three similar disk cartridges poses the following problems.
5) Discrimination of disk cartridges for each system
6) Prevention of erroneous insertion
7) The system of mounting the cartridge to the device is made applicable to both the front loading system and the tray loading system.
SUMMARY OF THE INVENTION
It is an object of the present invention to solve the above-described problems, and to provide a disk cartridge with increased capacity and capable of discrimination from similar and different disk cartridges, and a disk device using the same.
In order to solve the aforementioned problems, a disk cartridge and a disk device using the same according to the present invention including the following features.
1) A shutter for the disk cartridge is utilizable for both faces of the disk and is slidable in opposite directions with the structure of the disk cartridge being arranged so that the disk can be taken in and out. Also, the case of the disk cartridge is provided with a structure to prevent a cartridge of a different kind such as the CD caddy from being erroneously inserted.
2) A biasing arrangement for the shutter is provided at a position of the cartridge where the window of the case is closed.
3) When the disk is taken in and out, the structure of the disk cartridge is arranged to open at least a part thereof which is in a plane parallel to a plane of the disk.
4) When the disk is taken in and out, the structure of the disk cartridge is arranged to open a portion of the case at a position other than within a shutter moving range.
5) A disk conforming to the compact disk standards is enabled to be incorporated within the disk cartridge.
6) For biasing the shutter, one each of a torsion spring whose both arm portions directly engage with the case and the shutter is arranged in the corner areas on both sides of the disk cartridge across the shutter in a state in which the window of the case is closed.
7) A disk plane discrimination arrangement is provided which is capable of discriminating whether the plane of the disk on which recording and/or reproduction is performable on one side or both sides of the disk.
8) A disk plane specifying arrangement is provided which is capable of specifying which is the plane of the disk on which recording and/or reproduction is performable.
9) A discrimination arrangement for discriminating different kinds of disk cartridges is provided.
10) For discrimination or improper insertion prevention, a first cutout portion formed by cutting out at least a part of an outer plane of the disk cartridge which extends parallel to the disk plane of the disk for the disk cartridge of a different type, and a second cutout portion formed by cutting out at least a part of the outer plane of the disk cartridge which extends in a direction orthogonal to the disk plane for the disk cartridge of a different type.
11) The first cutout portion is arranged laterally symmetrically with respect to the inserting direction into a disk device.
Each of the aforementioned items 1) to 11) acts in the following manner as described in 1) to 11), respectively.
1) Even when the disk cartridge, which is applicable to both faces of the disk, is turned over for insertion to apply it to both faces or sides of the disk, it is made applicable by using one shutter open-and-close mechanism, thus making the disk within the cartridge replaceable.
2) Even if the shutter is intentionally opened, releasing the opening force automatically closes the shutter.
3) During opening, the disk plane can be easily seen, and the handle ability for taking the disk in and out is improved.
4) Any interference between the shutter and the opening structure is avoided.
5) A disk conforming to the compact disk standards is mountable to a disk device for new disk cartridges.
6) Manufacture of a shutter having a long stroke capable of opening in opposite directions by using a thin cartridge constructed with a small number of parts is enabled.
7) Easy recognition of whether the recording plane of the disk is on one side or both sides is enabled.
8) Easy recognition of which side is the recording plane of the disk is enabled.
9) Discrimination from any cartridge of a different type having nearly the same diameter is enabled.
10) For mounting a cartridge to the disk device, application to the front loading system and/or the tray loading system is enabled.
11) Even if the cartridge is inserted upside down into the device to apply it to both-face or side recording, it is possible to discriminate by one discrimination arrangement provided on the side of the device.
These and other objects, features and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1(a)-1(d) show a plan view and side views of a disk cartridge according to the present invention.
FIG. 2 is a plan view showing a state in which the insertion of a disk cartridge according to the present invention into a disk device has been started.
FIGS. 3(a) and 3(b) show a plan view and a side view of a state in which the insertion of a disk cartridge according to the present invention into the disk device has been completed.
FIGS. 4(a)-4(c) show views of construction of different forms of a discrimination hole provided for the shutter in a disk cartridge according to the present invention.
FIGS. 5(a) and 5(b) show a is a plan view and a side view of the construction of a discrimination hole or cutout provided in the case for a disk cartridge according to the present invention.
FIGS. 6(a)-6(d) show alternative constructions of a discrimination hole or cutout provided in the case for a disk cartridge according to the present invention.
FIG. 7 is a perspective view showing a disk cartridge according to another embodiment the present invention for a tray loading system.
FIG. 8 is a perspective view showing a conventional CD caddy.
FIG. 9 is a perspective view showing a disk cartridge of a PD system in accordance with the present invention.
FIG. 10 is a perspective view showing a disk cartridge and a disk device according to the present invention.
FIGS. 11(a) and 11(b) show a plan view and a side view of a disk cartridge and a disk device according to the present invention.
FIGS. 12(a) and 12(b) show a plan view and a side view of a disk cartridge of the PD system and a disk device according to the present invention.
FIGS. 13(a) and 13(b) show a plan view and a side view of a disk cartridge of the PD system and a disk device according to the present invention where the disk cartridge is improperly inserted.
FIGS. 14(a) and 14(b) show a plan view and a side view of the CD caddy and a disk device according to the present invention where the CD caddy is attempted to be inserted.
FIGS. 15(a) and 15(b) show a plan view and a side view of the outside dimensions of a disk cartridge according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings wherein like reference numerals are utilized to designate like parts, a first embodiment according to the present invention is described in conjunction with FIGS. 1 to 6, which embodiment corresponds to the so-called front loading system. FIGS. 1(a)-1(d) show a disk cartridge according to the present invention, with FIG. 1(a) being a partially exploded plan view, and FIGS. 1(b), 1(c) and 1(d) being side cross-sectional views as viewed from below, from the right side and from above, respectively.
A disk cartridge 100 according to the present invention is basically constituted by a disk 1 for recording information, a case formed by case portions 2 and 3 for housing the disk, a shutter 4 for opening and closing windows 2a and 3a in the case two springs 40 and 41 for biasing the shutter 4 and a door 5 for opening a part of the case. The disk 1 is capable of recording and reproducing a signal on both faces or sides thereof.
The case is formed divided into two sheets represented as case portions 2 and 3 sheets which are bonded together. Each of the case portions is formed with a window 2a or 3a which exposes a part of the disk plane so as to record and reproduce information. Dust-proof barrier plates 2p and 3p are formed between the disk 1 and the springs 40 and 41.
The shutter 4 is integrally formed as a U-shaped character with shutter planes 4a and 4b corresponding to the both faces of the disk respectively, and a side portion 4c, which integrally connects both shutter planes. Projections 4p and 4q engage with a guide groove 2g linearly formed in the case so that the shutter is linearly slidable in the right and left directions in the figure.
The two springs 40 and 41 may be torsion springs which are in a stretched state or helical tension springs, and exert a biasing force so that the shutter planes 4a and 4b of the shutter 4 maintain the windows 2a and 3a at their closing positions respectively. These two springs have the same shape so as not to increase the number of the parts and enabling a cost reduction. Each of these springs shown as torsion springs is mounted at two corner regions 50 and 51, respectively, which regions are provided between the two case 2 and 3, and which laterally sandwich the shutter 4 therebetween. The leading end of the arm of each of the respective springs is bent at a right angle to the axial direction of the coil portion, and each end 40a or 41a engages with a groove portion 2d or 3d at the case corner. Also, each of the other ends 40b or 41b engages with a stopper 3p or 3q having a V-shaped cross-section (see FIG. 3(a)) formed in the case portion 3 so that the springs are positioned with high precision in the up-and-down and the right-and-left directions in the figure because they are in the stretched state as described above. In this respect, according to the present invention, the torsion spring is constructed so that both ends thereof directly engage with the case without using other parts therebetween, thus not increasing the number of parts. Hooks 4d and 4e are integrally formed with the shutter 4 in coincidence with the above-described up-and-down and right-and-left positions of the torsion springs and with a deviation in height of the disk in the direction of thickness thereof, and innermost recesses in the grooves of the hooks 4d and 4e are positioned respectively. Thereby, the shutter 4 is retained at the central position shown in the right-and-left direction, i.e., the sliding direction in the figure.
In this respect, the sides of the case portions 2 and 3 as viewed from the direction of FIG. 1(b) are constructed to be opened, through which it is possible to insert these two springs once in one direction in a bent state for use in the cartridge and representing a very excellent assembly property.
A door 5 pivotally engages with the case 2 at pivot points 5a, 5b to open so that the disk can be taken in and out as shown by dotted lines of 5c and 1a in FIG. 1(c). Since the door 5 has a portion extending in a plane in parallel to the disk plane and this portion is opened, the disk has good visibility and good taking-in-and-out property when the door is opened. In this respect, the door 5 may be constructed to open at the side of the case in a manner similar to the cartridge for an 8 cm CD-ROM which is currently on the market. Also, when a disk such as, for example, a rental disk should not be taken out of the disk cartridge, the door 5 may be eliminated for preventing removal of the disk by a renter.
The operation when the shutter opens and closes the window is described with reference to FIG. 2 and FIGS. 3(a) and 3(b). In FIG. 2, when the disk cartridge 100 is inserted into a disk device 200 (a downward direction in the figure), a shutter opening lever 201 of the disk device 200 is supported by a pivot shaft 202 fixed on the device side, is biased clockwise in the figure by the spring 203, and stands by in contact with a stopper 204 so that the leading end 201a of the shutter opening lever 201 abuts an end 4r of the side portion of the shutter 4. When the disk cartridge is further inserted into the interior of the device 200 from this state, the shutter opening lever 201 rotates counterclockwise in the figure so as to cause the shutter 4 to slide toward the left side in the figure. When the sliding is started, the right-hand end 40b of the left-hand spring 40 is urged against the groove in the left-hand hook 4d in the shutter, as shown in FIG. 3(a), to engage therewith and to retract from the projection 3p of the case. On the other hand, while it is remaining urged against and engaged with the projection 3q of the case, the left-hand end 41b of the right-hand spring 41 in the figure retracts from the right-hand hook 4e in the shutter with the right-hand spring 41 retained as it is. With the sliding of the shutter 4, the right-hand end 40b of the left-hand spring 40 linearly moves to be deformed within the corner region 50, as shown in FIG. 3(a). On the side portion 4c of the shutter 4, there is provided a discrimination hole 4s (as shown more clearly in FIG. 3(b)), and at the position where the disk cartridge 100 has been inserted to the innermost position, a projection 210 is provided on the side of the disk device 200 correspondingly to the discrimination hole 4s such that the insertion of the disk cartridge 100 can be completed only when the projection 210 fits in the discrimination hole 4s. Then, a sensor (not shown) detects that the disk cartridge could be inserted to the completion position, and thereafter the entire disk cartridge 100 is moved toward the revolving shaft for the disk to complete the mounting of the disk so as to enable recording and/or reproduction by the disk device.
In the case of a CD caddy which does not have the discrimination hole 4s, the corresponding side portion 4c of a shutter 4 and the leading end of the projection 210 of the disk device collide with each other before the completion of insertion, thus preventing completion of the insertion. Thereby, the mounting of a CD caddy to the disk device is prevented.
In this respect, according to the present invention, the disk cartridge 100 is constructed laterally symmetrically in the state of FIG. 1. FIGS. 4(a)-4(c) and FIGS. 6(a)-6(d) are side views showing the external shape of the case portions 2 and 3 and the shutter 4. In FIG. 4(a), the discrimination hole 4s is formed at the center of the side portion 4c of the shutter 4 to show a point symmetry therein. When the disk cartridge 100 is turned over for insertion, the design is such that quite the same operation, as shown in FIG. 2 or FIGS. 3(a) and 3(b), can be performed when recording and reproducing on the rear or opposite plane thereof, and the mechanism on the side of the disk device 200, as shown in FIG. 2 or FIGS. 3(a) and 3(b), is capable of coping with the both faces of the disk only by one mechanism, thus achieving the simplified structure of the device and the reduced cost. Although the discrimination hole 4s is rectangular in the present embodiment, as shown in FIG. 4(a), it may be circular or the like, as shown in FIG. 4(b). Also, if a point symmetry is shown at the side portion 4c of the shutter 4 as described above, there may be a plurality of holes, as shown in FIG. 4(c). Also, on the orthogonal plane on the front edge side of the case portions 2 and 3 in the inserting direction, there may be provided cutout portions 20a and 20b so as to show a point symmetry on the orthogonal plane on the front edge side, as shown in FIGS. 5(a) and 5(b), so that a projection 210a is fitted correspondingly thereto. In addition, the cutout portion 20 is sufficient to show a point symmetry, and such layouts, as shown in FIGS. 6(a)-6(d), may be used.
Of the case external dimensions, the width, which is a frontage dimension for insertion into the device, and/or the thickness may be smaller than those of the CD caddy as the cartridge which should be prevented from being inserted.
For the disk utilized for one-side recording, only one of the cutout portions 20a and 20b which corresponds to the recording surface is formed, whereby it becomes possible to discriminate from both-face recording, and to further specify which face is the recording plane.
As regards a combination of the cutout portion of a particular shape and a corresponding projection, all detection arrangements including, for example, the following items can be substituted if a layout thereof is arranged to show a point symmetry on the orthogonal plane on the front edge side.
1) A combination of a light emission diode using an optical arrangement and a light receiving element.
2) A combination of a MR sensor using a magnetic arrangement and a magnet.
3) A combination of a ultrasonic wave oscillator using an acoustic arrangement and its receiver.
4) A combination of a contact switch using an electric arrangement and conductive material.
In this respect, when the disk cartridge 100 is taken out from the disk device 200, the operation is performed conversely to the foregoing, and in FIG. 1 to FIGS. 3(a) and 3(b), the right-hand end 40b of the left-hand spring 40 returns to a state where it is urged by the projection 3p of the case portion 3.
The construction using a torsion spring as the biasing arrangement for the shutter in the present embodiment may be such that one helical tension spring is arranged in a region in which no disk is arranged within the case in a manner to the CD caddy which is currently on the market, and which is occupied by the shutter located in a position where the window is closed.
FIG. 7 shows a second embodiment according to the present invention, wherein this embodiment corresponds to a disk device of the tray loading system in addition to the front loading system in the previously described embodiment. FIG. 7 shows a schematic external shape of the disk cartridge, and its interior and shutter structure are the same as those for the previously described first embodiment, but the disk taking-in-and-out structure is not adopted. As the discrimination arrangement and the erroneous insertion prevention arrangement in the front loading system, the cutout portions or grooves 20a and 20b structured in a manner similar to that shown in FIG. 6(a) are formed. In addition thereto, for discrimination and erroneous insertion prevention in the tray loading system, a plane parallel to the disk plane of the disk cartridge 100 is opened on both sides, and the cutout portions 302a and 302b, which pass through in its direction of thickness, are laterally symmetrically provided on the both sides correspondingly to the aforementioned cutout portions 20a and 20b respectively.
FIG. 8 is a perspective view of a conventional CD caddy. As shown, the conventional CD caddy 400 has no cutout portions open in a plane parallel to the disk plane. On the other hand, in FIG. 9, which is a perspective view of a disk cartridge 500 for the PD system, there are additionally provided, in accordance with the present invention, cutout portions 502a and 502b where one side of a plane parallel to the disk plane of the disk cartridge 500 has been opened correspondingly to the side of the recording plane of the one-side recording disk. In FIG. 10, reference numeral 200 designates a disk device; 251, a tray thereof; and 250, a draw-in command button for giving a command to start the tray draw-in operation. In the tray 251, two projections 252a and 252b are provided at positions and shapes corresponding to the cutout portions 302a and 302b.
FIGS. 11(a) and 11(b) show a construction in which a disk cartridge according to the present invention is mounted to the disk device with FIG. 11(a) being a plan view and FIG. 11(b) a side cross-sectional view. In FIG. 11(a), the two projections 252a and 252b provided in the tray 251 coincide with the cutout portions 302a and 302b provided in the disk cartridge 100 in both position and shape respectively for fitting in, and the tray 251 lowers to the lowest position thereof as shown in FIG. 11(b) to complete the mounting. In this state, the front of the draw-in command button 250 is accessible to permit the button to be pressed. In this respect, the disk according to the present invention can be used on both faces thereof. As described above, the projections 252a and 252b provided in the tray 251 and the cutout portions 302a and 302b provided in the disk cartridge 100 are laterally symmetrically provided respectively, and the cutout portions 302a and 302b are constructed so that the plane parallel to the disk plane of the disk cartridge 100 is opened on both sides to pass through in its direction of thickness, whereby the mounting can be completed in quite the same manner, even when the disk cartridge 100 is turned over to use its reverse side.
The construction in which the disk cartridge for the PD system, as shown in FIG. 9, is mounted is described with reference to FIGS. 12(a) and 12(b) and FIGS. 13(a) and 13(b). The disk for the PD system is used only on one side. FIGS. 12(a) and 12(b) show the construction when the disk cartridge is properly mounted with respect to the plane for use in the disk device with FIG. 12(a) being a plan view and FIG. 12(b) being a side cross-sectional view. In FIG. 12(a), the two projections 252a and 252b provided in the tray 251 coincide with the cutout portions 502a and 502b provided in the disk cartridge 500 in position, shape and height (depth) respectively for fitting in, and the tray 251 lowers to the lowest position thereof as shown in FIG. 12(b) to complete the mounting. In this state, the front of the draw-in command button 250 is accessible to permit the button to be pressed.
On the other hand, FIGS. 13(a) and 13(b) show a construction when the disk cartridge of FIG. 9 has been erroneously mounted to the disk device with its plane for use reversed with FIG. 13(a) being a plan view and FIG. 13(b) being a side cross-sectional view. In FIG. 13(a), the two projections 252a and 252b provided in the tray 251 cannot fit into the cutout portions 502a and 502b provided in the disk cartridge 500 so that the upper portion thereof cannot reach the lowest position of the tray 251 in FIG. 13(b). Accordingly, the mounting cannot be completed. In this state, the draw-in command button 250 is arranged so that the front thereof is rendered inaccessible by the disk cartridge 500 to prevent the button from being pressed.
In this manner,
1) The disk cartridge 500 cannot be accurately mounted.
2) Since the disk cartridge 500 is constructed to be inclined at this time, it is easy to recognize an abnormality.
3) The draw-in command button cannot be pressed.
By the foregoing arrangements, the operator is securely notified of the erroneous insertion. Also, the discrimination is provided ahead of the disk cartridge 500 in the inserting direction into the disk device 200, it is:
1) easy to recognize that the disk cartridge 500 cannot enter because the side of the disk cartridge near the inlet of the device is raised to deviate from the inlet; and
2) easy to use it also as a gripper for holding the disk cartridge 500 which is often provided in the same position.
Such effects as described above can be also obtained if in the two corner regions 50 and 51 of the disk cartridge as shown in FIG. 1(a), which are covered by the movement of the shutter 4, there are provided the discrimination arrangement, so that the discrimination arrangement is utilized for both the front loading system and the tray loading system. The remaining two corner regions of the disk cartridge can be left opened, and this leads to the effect that they can be utilized effectively and provided with a margin having, for example, a reference hole, a disk taking-in-and-out mechanism, or the like. Since the discrimination arrangement is provided at only one side with respect to of the position of the disk center, the discrimination arrangement for the front loading needn't increase the width of the disk cartridge, and this leads to the effect that the disk cartridge can be smaller in size.
FIGS. 14(a) and 14(b) show a construction when the CD caddy 400 which must not be mounted in the tray loading system has been erroneously mounted to the disk device with FIG. 14(a) being a plan view and FIG. 14(b) being a side cross-sectional view. Even if mounted with either side of the plane turned upward, the two projections 252a and 252b provided on the tray 251 in FIG. 14(a) cannot fit in the CD caddy 400, and the mounting cannot be completed in a manner similar to that of FIG. 13(b), thus preventing the draw-in command button 250 from being pressed. Such erroneous insertion can be securely avoided.
In this respect, for all the aforementioned three types of disks, it goes without saying that the structure is arranged to prevent the erroneous insertion even when an attempt to mount the disk cartridge is made in a state where it has been rotated by 90° or 180°.
FIGS. 15(a) and 15(b) show approximate outside dimensions of the disk cartridge according to the present invention with FIG. 15(a) being a plan view and FIG. 15(b) being a side view. In FIG. 15(a), reference numerals 150 and 151 denote the reference holes of the disk cartridge. The letter designations A-L in FIGS. 15(a) and 15(b) have the following dimensions:
A=125 mm
B=137 mm
C=115 mm
D=4 mm
E=0.7 mm
F=2 mm
G=102.5 mm
H=12 mm
I=10 mm
J=5 mm
K=8 mm
L=3 mm
According to the present invention, it is possible to provide a mass storage disk cartridge at low cost in the CD system or the disk system having the substantially same dimensions as it, and there is also provided the effect that it is possible to securely discriminate any disk cartridge of a different type having substantially the same shape.
While we have shown and described several embodiments in accordance with the present invention, it is understood that the same is not limited thereto but is susceptible of numerous changes and modifications as known to those skilled in the art, and we therefore do not wish to be limited to the details shown and described herein but intend to cover all such changes and modifications as are encompassed by the scope of the appended claims. | A disk cartridge system having different types of disk cartridges for use in a disk cartridge drive apparatus. A first disk cartridge includes a first case having a substantially rectangular shape with first, second, third and fourth edges, the first edge of the case being delimited by a first corner portion connecting the first edge and second edge and a second corner portion connecting the first edge and the third edge, the first case having a first cutout portion at both of the second and third edges and extending in a direction and passing through a thickness of the first case, and a first disk being housed in the first case. A second disk cartridge includes a second case with a substantially rectangular shape with fifth, sixth, seventh and eighth edges, the fifth edge of the second case being delimited by a fifth corner portion connecting the fifth edge and sixth edge and a sixth corner portion connecting the fifth edge and the seventh edge, the second case having a second cutout portion at both of the sixth and seventh edge and extending in a direction of a thickness of the second case without passing through the thickness of the second case, and a second disk being housed in the second case. A length, width and thickness of the first case are substantially equal to a length, width and thickness of the second case and a diameter and thickness of the first disk are substantially equal to a diameter and width of the second disk. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates in general to data transmission in mobile communications systems and more particularly card application toolkit support for Internet Protocol (IP) multimedia systems.
[0003] 2. Description of the Related Art
[0004] In known wireless telecommunications systems, transmission equipment in a base station or access device transmits signals throughout a geographical region known as a cell. As technology has evolved, more advanced equipment has been introduced that can provide services that were not possible previously. This advanced equipment might include, for example, an E-UTRAN (evolved universal terrestrial radio access network) node B (eNB), a base station or other systems and devices. Such advanced or next generation equipment is often referred to as long-term evolution (LTE) equipment, and a packet-based network that uses such equipment is often referred to as an evolved packet system (EPS). An access device is any component, such as a traditional base station or an LTE eNB (Evolved Node B), that can provide a user agent (UA), such as user equipment (UE) or mobile equipment (ME), with access to other components in a telecommunications system.
[0005] In mobile communication systems such as an E-UTRAN, the access device provides radio accesses to one or more UAs. The access device comprises a packet scheduler for allocating uplink (UL) and downlink (DL) data transmission resources among all the UAs communicating to the access device. The functions of the scheduler include, among others, dividing the available air interface capacity between the UAs, deciding the resources (e.g. sub-carrier frequencies and timing) to be used for each UA's packet data transmission, and monitoring packet allocation and system load. The scheduler allocates physical layer resources for physical downlink shared channel (PDSCH) and physical uplink shared channel (PUSCH) data transmissions, and sends scheduling information to the UAs through a control channel. The UAs refer to the scheduling information for the timing, frequency, data block size, modulation and coding of uplink and downlink transmissions.
[0006] In certain mobile communication systems, there is a requirement for a universal integrated circuit card (UICC) application (e.g., a subscriber identity module (SIM), an Internet Protocol (IP) multimedia subsystem (IMS) SIM (ISIM), and a universal terrestrial radio access network (UTRAN) SIM (USIM)) may make use of Internet Protocol (IP) multimedia subsystem (IMS) functionalities controlled by mobile equipment (ME). See e.g., 3GPP TS 22.101. For example, FIG. 1 , labeled Prior Art, shows a block diagram of an operation where a UICC application invites a peer to a session. FIG. 2 , labeled Prior Art, shows an example of a UICC to IMS communication. In this example, an IMS UICC user initiated registration is performed where an IMS Subscriber Identity module (ISIM) is present.
[0007] It is possible that new UICC to ME command may include an open channel for IMS function which extends known Bearer Independent Protocol (BIP) commands for IMS like Close Channel, Send data, Receive data and Get Channel Status to allow the channel to use the IMS as a means to send and receive IMS traffic to and from the UICC.
[0008] In certain known systems (e.g., 3GPP 31.111 v. 9.1) the UICC can use the Open Channel request to activate a PDP Context and to send IP data from the UICC to the network on an access point name (APN) chosen by the UICC. This function is in place under hospices of BIP that would allow for IP based over the air (OTA) updating of the UICC to replace the aging short message service (SMS) push and SMS transport currently in use.
[0009] This function takes the BIP feature further where the UICC is another IMS application and/or IMS communication service on the UE and as with other applications/communication services requires specific registration with the IMS service using an IMS application reference identifier/IMS communication service identifier (IARI/ICSI).
[0010] However, with this function, sending multiple registrations over session initiation protocol (SIP) can be costly for the mobile (e.g., in terms of battery life) and for the network (e.g., in terms of presenting unnecessary load). Additionally, unsolicited SIP messages pushed by the network can also have the same impact.
[0011] More specifically, if the a device is unaware of the IARI(s) hosted on the UICC at the time of the first registration of the device, the device will have to perform subsequent registrations when the UICC informs (at a later time) that the UICC wants the ME to initiate an IMS connection. The extra registrations can result in unnecessary and unwanted signaling. After boot up and after the SIP/IMS registration but before receiving the Open Channel command from the UICC; if the ME receives an incoming push message for an application (identified by an IARI) hosted on the UICC, the ME will simply discard any unsolicited messages from the IMS server.
[0012] Likewise, if the ME is unaware of the communication services (e.g., ICSI(s)) supported by applications contained within the UICC at the time of its first registration the ME will have to perform a subsequent registration later to support particular ICSI(s) contained in the UICC. The SIP REGISTER message contains media feature tags containing ICSI(s) along with IARI(s) values. For example, as shown in FIGS. 4 and 5 it would be desirable to provide enhanced support multiple IARI and ICSI values in the REGISTER and INVITE messages.
SUMMARY OF THE INVENTION
[0013] In accordance with the present invention, to consolidate the SIP messages as much as possible the ME is made aware of all the IMS applications installed in its memory and on the UICC and supported communication services. By obtaining this information at boot-up time, the ME can save resources by registering all local applications and communication services in single IMS registration.
[0014] In various embodiments, there is a plurality of solutions to solve the IARI issue. Also, in various embodiments, the missing ICSI issue is addressed. Also, in certain embodiments, a UICC IMPU solution is set forth. Also, in certain embodiments, the solutions to provide the IMS registration state to the UICC after a successful IMS registration is set forth.
[0015] More specifically, in one embodiment, the invention relates to introducing a new ISIM file to indicate the UICC IARIs to a UE. More specifically, in this embodiment the invention relates to introducing a new ISIM file that contains all the IARIs associated with active applications installed on the UICC. The mobile device (such as a ME) reads this file at boot-up and becomes aware of the presence of the IMS applications present on the UICC. In certain variations of this embodiment, if any associated IARI needs to be added or removed at a later time the file is updated and a notification is sent to the device. Upon receipt of these notifications the ME updates its IMS registration using the SIP REGISTER messages to add or remove the associated IARIs.
[0016] In another embodiment, the invention relates to introducing a new USIM file to indicate the UICC IARIs to the UE. More specifically, in this embodiment, the invention relates to using a USIM if an ISIM application is not present. In this embodiment, a new USIM file is introduced that contains all the IARIs associated with active applications installed on the UICC. The device reads the USIM file at boot-up and becomes aware of IMS applications that are present on the card. In certain variations of this embodiment, if any associated IARI needs to be added or removed at a later time the file is updated and a notification is sent to the device. Upon receipt of these notifications the ME updates its IMS registration using the SIP REGISTER messages to add or remove the associated IARIs.
[0017] In another embodiment, the invention relates to using event download to notify the UICC of incoming data. More specifically, in this embodiment the invention relates to notifying the UICC of any incoming data on any given application identified by the IARI. The UICC registers to an incoming data event on the ME.
[0018] In another embodiment, the invention relates to introducing a file in an ISIM or USIM to indicate an ICSI(s) to the UE. More specifically, in this embodiment the invention relates to introducing an ISIM file that contains all the supported communications services identified by ICSI(s). The device reads this file at boot-up and becomes aware of the presence of the IMS communication services to be supported by applications on the UICC. In this embodiment, if the ISIM application is not present then this method uses USIM. Additionally, in variations of this embodiment, the method introduces a USIM file that contains all the supported communications service identified by ICSI(s). The device reads this file at boot-up and becomes aware of the presence of the IMS communication services supported by applications on the UICC. If any associated ICSIs are added or removed at a later time the file is updated and a notification is sent to the device. Upon receipt of these notifications the UE updates its IMS registration using the SIP REGISTER messages to add or remove the associated ICSI(s).
[0019] In another embodiment, the invention relates to introducing a file in ISIM or USIM to indicate a UICC's IMPUs to an ME. More specifically, in this embodiment, the invention relates to storing a unique ID on an USIM/ISIM, an IMPU or several IMPUs. In this embodiment, the ME routes the incoming IMS data for the UICC IMPU directly to the card. The IMPU is not necessarily part a current IMPU list stored on the ISIM; the current IMPU list may be part of the implicit registration set and received by the ME during IMS registration.
[0020] In another embodiment, the invention relates to indicating to a UICC that the ME has registered with an IMS after an initial 200 OK message. More specifically, in this embodiment, once the ME has successfully registered with the IMS network the ME notifies the UICC when the IMS network is available. In this embodiment, the trigger of the ME to UICC event is the 200 OK that is returned from the network after the SIP REGISTER message.
[0021] In another embodiment, the invention relates to indicating to a UICC that a ME has registered with IMS after each notify associated with a registration event package. More specifically, in this embodiment once the ME has successfully registered with the IMS network, the ME notifies the UICC when the IMS network is available. Subsequent registration state changes during an IMS session also result in notifying to the UICC of these events to prevent the UICC of attempting to send data when there is no IMS registration available. The trigger of the ME to UICC event in this case is a SIP NOTIFY message that comes from the IMS network.
[0022] In certain variations of this embodiment, the ME to UICC communication may contain a list of Registered IMPUs. In other variations of this embodiment, the list can be filtered according the list of IMPUs as discussed above. In other variations of this embodiment, the list may contain a list of Registered IARIs and/or a list of Registered ICSIs. In another variation of this embodiment, the list can also be filtered according to the lists provided in an UICC file.
[0023] The present invention includes a plurality of benefits such as allowing the ME to have knowledge of all UICC identities at bootup time. The knowledge results in an ability to consolidate all IARIs into a first SIP REGISTER message and reduce unwanted SIP signaling. The invention also allows operators to change the IARIs as necessary if such a change becomes necessary.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The present invention may be better understood, and its numerous objects, features and advantages made apparent to those skilled in the art by referencing the accompanying drawings. The use of the same reference number throughout the several figures designates a like or similar element.
[0025] FIG. 1 , labeled Prior Art, shows a block diagram of a UICC invite a peer to session operation.
[0026] FIG. 2 , labeled Prior Art, shows a flow diagram of a UICC to IMS channel establishment operation.
[0027] FIG. 3 , labeled Prior Art, shows a flow diagram of an IMS data transmission.
[0028] FIG. 4 , labeled Prior Art, shows a flow diagram of an example of an extra registration.
[0029] FIG. 5 , labeled Prior Art, shows a flow diagram of an example of an unsolicited SIP invite message.
[0030] FIG. 6 shows a flow diagram of an example of a poke and pull of a bearer independent protocol.
[0031] FIG. 7 shows a flow chart of the operation of a ME determining IARI support in a UICC.
[0032] FIG. 8 shows a flow diagram of a message sequence of an ME determining IARI support in a UICC.
[0033] FIG. 9 shows flow diagram of another portion of a message sequence of an ME determining IARI support in a UICC.
[0034] FIG. 10 shows a flow chart of the operation of determining if any supplementary registration is required.
[0035] FIG. 11 shows a flow diagram of reading an IARI from a USIM.
[0036] FIG. 12 shows a mapping of a plurality of bytes of an elementary file.
[0037] FIG. 13 shows a flow diagram of a UICC removing an IARI from a list to deregister the IARI.
[0038] FIG. 14 shows a flow diagram of establishing an appropriate event download for a push IMS.
[0039] FIG. 15 shows a mapping of a feature in the USAT Terminal Profile
[0040] FIG. 16 shows a flow diagram of a UICC receiving an IMS registration event.
[0041] FIG. 17 shows a diagram of a wireless communications system including a UE operable for some of the various embodiments of the disclosure.
[0042] FIG. 18 shows a block diagram of a UE operable for some of the various embodiments of the disclosure.
[0043] FIG. 19 shows a diagram of a software environment that may be implemented on a UE operable for some of the various embodiments of the disclosure.
[0044] FIG. 20 shows a block diagram of an illustrative general purpose computer system suitable for some of the various embodiments of the disclosure.
DETAILED DESCRIPTION
[0045] Referring to FIG. 7 , a flow chart of the operation for a ME to determine IARI support in a UICC is shown. The system includes a mechanism to determine if an IARI is present on the USIM rather than on the ISIM. In certain embodiments, it is possible to have only a USIM application on the UICC.
[0046] More specifically, the operation begins by determining if an ISIM is present in the UICC at step 710 . If an ISIM is present, then the operation proceeds to read an ISIM service table at step 720 . Next, at step 722 , the operation determines whether an IARI list is enabled. If the list is enabled, then at step 724 , the operation reads the IARI list.
[0047] If the ISIM is not present, then the operation proceeds to determine with a USIM application is present at step 730 . If a USIM application is present, then the USIM service table is read at step 732 . Next, the operation determines whether an IARI list is enabled at step 734 . If the IARI list is enabled, then the IARI list is read at step 736 . If the IARI list is not enabled, then the operation determines that there is not support for the IARI in the UICC at step 738 .
[0048] Referring to FIG. 8 , a flow diagram of a message sequence of an ME determining IARI support in a UICC is shown. More specifically, the ME verifies that an ISIM file is present, Next, the ISIM provides the service table to the ME, which verifies the ISIM service table and look for a particular service (e.g., service XX). Next, the ME reads an IARI file and the ISIM provides an IARI list (IARI3) to the ME. Next, the ME provides the IMS with a session initiation via a SIP REGISTER. An example of an ISIM service table (EF IST ) is set forth in Table 1.
[0049] This elementary File (EF) indicates which optional services are available. If a service is not indicated as available in the ISIM, the ME shall not select the service. In certain embodiments, the presence of this file is mandatory if optional services are provided in the ISIM.
[0000]
TABLE 1
Identifier: ‘6F07’
Structure: transparent
Optional
SFI: ‘07’
File size: X bytes, X >= 1
Update activity: low
Access Conditions:
READ
PIN
UPDATE
ADM
DEACTIVATE
ADM
ACTIVATE
ADM
Bytes
Description
M/O
Length
1
Services n° 1 to n° 8
M
1 byte
2
Services n° 9 to n° 16
O
1 byte
3
Services n° 17 to n° 24
O
1 byte
4
Services n° 25 to n° 32
O
1 byte
etc.
X
Services n° (8X-7) to n° (8X)
O
1 byte
Services
Contents:
Service n° 1:
P-CSCF address
Service n° 2
Generic Bootstrapping Architecture
(GBA)
Service n° 3
HTTP Digest
Service n° 4
GBA-based Local Key Establishment
Mechanism
Service n° 5
Support of P-CSCF discovery for IMS
Local Break Out
Service n° X
IARIs associated to active UICC IMS
applications
[0050] Once the ME determines that the IARI file is available and present (see e.g., step 722 of FIG. 7 ), the ME uses a select command to read the contents of the IARI list. An example of the IARI list (EF IAAUIA ) is set forth in Table 2. If the service X (X representing a placeholder value) is available, the IARI file is present. The EF contains a list of active IARIs that need to be registered on the initial IMS registration of the UE. In this embodiment, the structure of the EF is linear fixed while in other embodiments it is transparent.
[0000]
TABLE 2
Identifier: ‘6FXX’
Structure: linear fixed
Optional
SFI: ‘YY’
Record length: X bytes; X ≧ 3
Update activity: low
Access Conditions:
READ
ALWAYS
UPDATE
ADM
ACTIVATE
ADM
DEACTIVATE
ADM
Bytes
Description
M/O
Length
1 to X
IARI TLV objects
M
X bytes
IARI TLV objects.
The content and coding (Full name for network and Short name for
network) is defined below).
Coding of the Network name TLV objects
Length
Description
Status
1 byte
IARI TLV TAG
M
X byte
Length of IARI
M
Y bytes
IARI value
M
IARI value shall be coded as defined in 3GPP TS 24.229.
Unused bytes shall be set to ‘FF’.
[0051] Referring to FIG. 9 , flow diagram of another portion of a message sequence of an ME determining IARI support in a UICC is shown. More specifically, the ME then includes the IARIs in the SIP REGISTER request pursuant to 3GPP TS 24.229.
[0052] In certain embodiments, the UICC may request a deregistration or a new registration of an IARI by sending a file Refresh proactive command on EF IAAUIA . More specifically, the Refresh command is set forth in Table 3.
[0000]
TABLE 3
REFRESH
Description
Clause
M/O/C
Min
Length
Proactive UICC command Tag
9.2
M
Y
1
Length (A + B + C + D + E + F +
—
M
Y
1 or 2
G + H)
Command details
8.6
M
Y
A
Device identities
8.7
M
Y
B
File List
8.18
C
N
C
AID
8.60
O
N
D
Alpha identifier
8.2
O
N
E
Icon identifier
8.31
O
N
F
Text Attribute
8.72
C
N
G
Frame Identifier
8.80
O
N
H
[0053] For the refresh modes “File Change Notification,” “NAA Initialization and File Change Notification,” and “NAA Session Reset,” the UICC supplies a File List data object, indicating which EFs need to be refreshed. For other modes, inclusion of a File List is optional, and the terminal ignores it. In certain embodiments, the refresh request is defined in ETSI TS 102 223.
[0054] Referring to FIG. 10 , a flow chart of the operation of determining if any supplementary registration is required is shown. In certain embodiments, the ME includes IARI management that will detect if any IARIs have been removed and if any have been added. The ME will then re-issue a new registration to IMS to reflect this change.
[0055] More specifically, at step 1010 , the ME receives a refresh command from the UICC. Next, at step 1020 , the ME reads the new IARI list present in the UICC and at step 1022 , compares the new list with the IARI list that is stored within the ME memory. If the list is changed, then the ME updates the list in the ME memory at step 1030 and transmits a new SIPREGISTER command to the IMS network at step 1032 . If the list is unchanged, then the ME does nothing (step 1040 ).
[0056] Referring to FIG. 11 , a flow diagram of an operation of reading an IARI from a USIM is shown. More specifically, if the ME determines that there is no ISIM present (see e.g., step 710 of FIG. 7 ) or that the ISIM doesn't support the IARI list feature (see e.g., step 722 of FIG. 7 ), then the ME reads the information from the USIM.
[0057] More specifically, first the device determines whether the USIM file is present (see e.g., step 730 of FIG. 7 ). The ME then verifies the USIM service table and look for service XX (XX representing a placeholder value).
[0058] If the service XX is available, the USIM file is present. The EF indicates which services are available. More specifically, the USIM file is set forth as EF UST (USIM Service Table) at Table 4.
[0000]
TABLE 4
Identifier: ‘6F38’
Structure: transparent
Mandatory
SFI: ‘04’
File size: X bytes, (X ≧ 1)
Update activity: low
Access Conditions:
READ
PIN
UPDATE
ADM
DEACTIVATE
ADM
ACTIVATE
ADM
Bytes
Description
M/O
Length
1
Services n° 1 to n° 8
M
1 byte
2
Services n° 9 to n° 16
O
1 byte
3
Services n° 17 to n° 24
O
1 byte
4
Services n° 25 to n° 32
O
1 byte
etc.
X
Services n° (8X-7) to n° (8X)
O
1 byte
Services
Contents:
Service n° 1:
Local Phone Book
Service n° 2:
Fixed Dialling Numbers (FDN)
Service n° 3:
Extension 2
Service n° 4:
Service Dialling Numbers (SDN)
Service n° 5:
Extension3
Service n° 6:
Barred Dialling Numbers (BDN)
Service n° 7:
Extension4
Service n° 8:
Outgoing Call Information (OCI and OCT)
Service n° 9:
Incoming Call Information (ICI and ICT)
Service n° 10:
Short Message Storage (SMS)
Service n° 11:
Short Message Status Reports (SMSR)
Service n° 12:
Short Message Service Parameters (SMSP)
Service n° 13:
Advice of Charge (AoC)
Service n° 14:
Capability Configuration Parameters 2
(CCP2)
Service n° 15:
Cell Broadcast Message Identifier
Service n° 16:
Cell Broadcast Message Identifier Ranges
Service n° 17:
Group Identifier Level 1
Service n° 18:
Group Identifier Level 2
Service n° 19:
Service Provider Name
Service n° 20:
User controlled PLMN selector with Access
Technology
Service n° 21:
MSISDN
Service n° 22:
Image (IMG)
Service n° 23:
Support of Localised Service Areas (SoLSA)
Service n° 24:
Enhanced Multi-Level Precedence and Pre-
emption Service
Service n° 25:
Automatic Answer for eMLPP
Service n° 26:
RFU
Service n° 27:
GSM Access
Service n° 28:
Data download via SMS-PP
Service n° 29:
Data download via SMS-CB
Service n° 30:
Call Control by USIM
Service n° 31:
MO-SMS Control by USIM
Service n° 32:
RUN AT COMMAND command
Service n° 33:
shall be set to ‘1’
Service n° 34:
Enabled Services Table
Service n° 35:
APN Control List (ACL)
Service n° 36:
Depersonalisation Control Keys
Service n° 37:
Co-operative Network List
Service n° 38:
GSM security context
Service n° 39:
CPBCCH Information
Service n° 40:
Investigation Scan
Service n° 41:
MexE
Service n° 42:
Operator controlled PLMN selector with
Access Technology
Service n° 43:
HPLMN selector with Access Technology
Service n° 44:
Extension 5
Service n° 45:
PLMN Network Name
Service n° 46:
Operator PLMN List
Service n° 47:
Mailbox Dialling Numbers
Service n° 48:
Message Waiting Indication Status
Service n° 49:
Call Forwarding Indication Status
Service n° 50:
Reserved and shall be ignored
Service n° 51:
Service Provider Display Information
Service n° 52
Multimedia Messaging Service (MMS)
Service n° 53
Extension 8
Service n° 54
Call control on GPRS by USIM
Service n° 55
MMS User Connectivity Parameters
Service n° 56
Network's indication of alerting in the
MS (NIA)
Service n° 57
VGCS Group Identifier List (EF VGCS and
EF VGCSS )
Service n° 58
VBS Group Identifier List (EF VBS and
EF VBSS )
Service n° 59
Pseudonym
Service n° 60
User Controlled PLMN selector for
I-WLAN access
Service n° 61
Operator Controlled PLMN selector for
I-WLAN access
Service n° 62
User controlled WSID list
Service n° 63
Operator controlled WSID list
Service n° 64
VGCS security
Service n° 65
VBS security
Service n° 66
WLAN Reauthentication Identity
Service n° 67
Multimedia Messages Storage
Service n° 68
Generic Bootstrapping Architecture (GBA)
Service n° 69
MBMS security
Service n° 70
Data download via USSD and USSD
application mode
Service n° 71
Equivalent HPLMN
Service n° 72
Additional TERMINAL PROFILE after
UICC activation
Service n° 73
Equivalent HPLMN Presentation Indication
Service n° 74
Last RPLMN Selection Indication
Service n° 75
OMA BCAST Smart Card Profile
Service n° 76
GBA-based Local Key Establishment
Mechanism
Service n° 77
Terminal Applications
Service n° 78
Service Provider Name Icon
Service n° 79
PLMN Network Name Icon
Service n° 80
Connectivity Parameters for USIM IP
connections
Service n° 81
Home I-WLAN Specific Identifier List
Service n° 82
I-WLAN Equivalent HPLMN Presentation
Indication
Service n° 83
I-WLAN HPLMN Priority Indication
Service n° 84
I-WLAN Last Registered PLMN
Service n° 85
EPS Mobility Management Information
Service n° 86
Allowed CSG Lists and corresponding
indications
Service n° 87
Call control on EPS PDN connection by
USIM
Service n° 88
HPLMN Direct Access
Service n° 89
eCall Data
Service n° 90
Operator CSG Lists and corresponding
indications
Service n° XX
IARIs associated to active UICC IMS
applications
[0059] The EF UST contains at least one byte. Further bytes may be included, but if the EF UST includes an optional byte, then the EF will also contain all bytes before that byte. Other services are possible in the future and may be coded on further bytes in the EF UST . The coding falls under the responsibility of the 3GPP.
[0060] More specifically, FIG. 12 shows a mapping of a plurality of bytes of the EF UST . In this mapping, on bit is used for each service where a 1 indicates a service is available and a 0 indicates a service is not available. When a service is available the USIM has the capability to support the service and the service is available for the user of the USIM unless the service is identified as disabled in the file EF EST . When a service not available the service is not to be used by the USIM user, even if the USIM has the capability to support the service. More specifically, EF EST is set forth in Table 5. The file EF EST is present when a service n 2 , 6 or 35 is available as indicated within a USIM service table. The file EF EST indicates which services are enabled. If a service is not indicated as enabled the file EF EST , the ME does not select the service. In another embodiment, for an ISIM environment, an EF IEST file may be used.
[0000]
TABLE 5
Identifier: ‘6F56’
Structure: transparent
Optional
SFI: ‘05’
File size: X bytes, (X ≧ 1)
Update activity: low
Access Conditions:
READ
PIN
UPDATE
PIN2
DEACTIVATE
ADM
ACTIVATE
ADM
Bytes
Description
M/O
Length
1
Services n° 1 to n° 8
M
1 byte
2
Services n° 9 to n° 16
O
1 byte
etc.
X
Services n° (8X-7) to n° (8X)
O
1 byte
Services
Contents:
Service n° 1:
Fixed Dialling Numbers (FDN)
Service n° 2:
Barred Dialling Numbers (BDN)
Service n° 3:
APN Control List (ACL)
[0061] The EF contains at least one byte. Further bytes may be included, but if the EF includes an optional byte, then the EF also contains all bytes before that byte. Other services are possible. The coding falls under the responsibility of the 3GPP. Mores specifically, with the coding, one bit is used to code each service where a 1 indicates that a service is activated and a 0 indicates that a service is deactivated. All unused bits are set to 0. A service which is listed in the is enabled if it is indicated as available in the USIM service table and indicated as activated in the enabled services table.
[0062] Once the ME has determined that the file is available and present, the ME uses the select command to read the contents of the file EF IAAUIA . The file EF IAAUIA contains a list of active IARIs that need to be registered on an initial IMS registration of a UE. The file EF IAAUIA is set forth in Table 6.
[0000]
TABLE 6
Identifier: ‘6FXX’
Structure: linear fixed
Optional
SFI: ‘YY’
Record length: X bytes; X ≧ 3
Update activity: low
Access Conditions:
READ
ALWAYS
UPDATE
ADM
ACTIVATE
ADM
DEACTIVATE
ADM
Bytes
Description
M/O
Length
1 to X
IARI TLV objects
M
X bytes
Where the content and coding of IARI TLV objects (Full name for
network and Short name for network) is defined as:
Coding of the Network name TLV objects
Length
Description
Status
1 byte
IARI TLV TAG
M
X byte
Length of IARI
M
Y bytes
IARI value
M
[0063] The ME then includes the IARIs in a SIP REGISTER request pursuant to 3GPP TS 24.229. In certain embodiments, if a linear fixed structure is used then the unused bits are set to FF.
[0064] Referring to FIG. 13 , a flow diagram of a UICC removing an IARI from a list to deregister the IARI. In certain embodiments, the UICC may request a deregistration or a new registration of an IARI by sending a file Refresh proactive command on EF IAAUIA . More specifically the Refresh command is set forth in Table 7.
[0000]
TABLE 7
REFRESH
Description
Clause
M/O/C
Min
Length
Proactive UICC command Tag
9.2
M
Y
1
Length (A + B + C + D + E + F +
—
M
Y
1 or 2
G + H)
Command details
8.6
M
Y
A
Device identities
8.7
M
Y
B
File List
8.18
C
N
C
AID
8.60
O
N
D
Alpha identifier
8.2
O
N
E
Icon identifier
8.31
O
N
F
Text Attribute
8.72
C
N
G
Frame Identifier
8.80
O
N
H
[0065] For the refresh modes “File Change Notification,” “NAA Initialization and File Change Notification,” and “NAA Session Reset,” the UICC supplies a File List data object, indicating which EFs need to be refreshed. For other modes, inclusion of a File List is optional, and the terminal ignores it.
[0066] In certain embodiments, the ME includes IARI management that will detect if any IARIs have been removed and if any have been added. The ME will then re-issue a new registration using the SIP REGISTER message to IMS to reflect this change.
[0067] Referring to FIG. 14 , a flow diagram of establishing an appropriate event download for a push IMS is shown. In certain embodiments, the method uses an event download operation to notify the UICC of incoming data. In this embodiment, the UICC verifies the terminal profile for the ME support of the event.
[0068] The UICC registers the Event Download command so as to be notified of any incoming data request for the UICC application associated with the IARI or IARIs. If the feature is supported in any radio technology, the UICC proceeds with registering the Incoming IMS data event via a set up event list USAT command. The mapping of the thirty first byte of the UICC is shown in FIG. 15 .
[0069] More specifically, with the set up event list USAT command, the UICC uses this command to supply a set of events. This set of events becomes the current list of events for which the terminal is to monitor. Any subsequent set up event list command replaces the current list of events supplied in a previous set up event list command. The set up event list command can also be used to remove an entire list of events. The set up event list command can also be used to remove an entire list of events current in the terminal. The list of events provided by the UICC in the last set up event list command will be removed if the terminal is powered off or the UICC is removed or a reset is performed. When the terminal has successfully accepted or removed the list of events, the terminals sends a terminal response command performed successfully to the UICC. When the terminal is not able to successfully accept or remove the list of events, the terminal sends a terminal response of command beyond terminal's capabilities. When one of the events in the current list occurs, then the terminal uses an ENVELOPE (EVENT DOWNLOAD—Incoming IMS data) mechanism to transfer details of the event to the UICC.
[0070] For the event list byte coding, a plurality of values are defined in addition to those defined for 3GPP within TS 31.111. More specifically, the values can further include a byte value of 11 for an I-WLAN access status event, a value of 12 for a network rejection event, a value of 15 for a CSG cell selection event and a placeholder value of 1× for incoming IMS data event where each event would receive a new value.
[0071] If the UICC doesn't have its IMS channel opened with the ME, the ME buffers the incoming data and uses the envelope command to inform the UICC that it has incoming IMS to UICC transmissions. In certain embodiments the envelope can contain one or more IARIs, in other embodiments the envelope provides a reference to the IARI values stored in the USIM or ISIM to reduce the size of the envelope command.
[0072] More specifically, with respect to an incoming IMS data event, if the incoming IMS data event is part of a current event list (as set up by the last set up event list command) then in the case of an incoming IMS message to an active UICC application's associated IARI the terminal informs the UICC that this event has occurred by using an envelope (event download incoming IMS data) command. The direction of the command is ME to UICC and the command header is specified in 3GPP TS 31.111. Additionally, the structure of the envelope (event download incoming IMS data) command is defined as set forth in Table 8.
[0000]
Direction: ME to UICC.
Command parameters/data.
Description
Clause
M/O
Min
Length
Event download tag
9.1
M
Y
1
Length (A + B + (C or D or I) + E +
—
M
Y
1
F + G + H) + J
Event list
8.25
M
Y
A
Device identities
8.7
M
Y
B
IARI List
8.9X
M
Y
G
Event list: the Event list data object shall contain only one event (value part of length 1 byte), and terminal shall set the event to:
Incoming IMS Data event.
Device identities: the terminal shall set the device identities to:
source: Network;
destination: UICC.
IARI: This data object contains the IARI to which the incoming data is the destination in the UICC.
Response parameters/data: None for this type of ENVELOPE command.
[0073] Additionally, the IARI list is set forth in Table 8.
[0000]
TABLE 8
Byte(s)
Description
Length
1
IARI Tag
1
2
Length
X
3
IARI value
X
Contents: The UICC IARI set it in the destination field read by the ME.
Coding: IARI value shall be coded as defined in 24.229.
[0074] Finally, the UICC sets up a channel with the appropriate IARI identifier and the ME begins relaying all IMS traffic using this channel.
[0075] In certain embodiments, a new file is introduced in an ISIM or USIM to indicate the ICSI(s) to the ME. With this embodiment, the operation allows the ME to know about the associated services (ICSI(s)) supported by the applications on the UICC using the ISIM or USIM. The operation is similar to the operations discussed above with certain exceptions.
[0076] For example, in this embodiment the device verifies that the file is present, it will verify the ISIM service table (EF IST ) and look for service YY (where YY is a placeholder value) if ISIM is present and the application on the UICC supports the communications services identified by the ICSI. If ISIM is not present or does not support the ICSI and a USIM is available then the device verifies the USIM service table (EF UST ) and looks for service YY where:
[0077] Service n°YY UICC ICSI
[0078] Once the device has determined that the file is available and present, the device uses the select command to read the contents of the file EF UICCICSI .
[0079] The device then includes the ICSI(s) in a REGISTER request as defined by 3GPP TS 24.229.
[0080] In certain embodiments, a new file is introduced in an ISIM or USIM to indicate an IMPU of a UICC to the ME. With this embodiment, the operation allows ME to know about the subscribed IMPUs through ISIM or USIM. The operation is similar to operation discussed above with certain exceptions.
[0081] For example, in this embodiment, the device verifies that the file is present, it will verify the ISIM service table (EF IST ) and look for service ZZ (where ZZ is a placeholder value) if ISIM is present. If ISIM is not present and a USIM is available then the device verifies the USIM service table (EF UST ) and look for service ZZ where:
[0082] Service n°ZZ UICC IMPUs
[0083] Once the device has determined that the file is available and present the device uses the select command to read the contents of EF UICCIMPU .
[0084] The device then registers (if necessary) one by one the IMPUs that are not registered as part of the implicit registration previously sent to the ME.
[0085] Certain embodiments further include a feature of indicating to the UICC that the ME has registered successfully with IMS after an initial 200 OK message. (A 200 OK message is a standard response for successful SIP requests.) Once the ME has successfully registered with the IMS network, the ME indicates to the UICC that the registration was successful. In certain embodiments, the ME can provide the UICC the list IMS registered IMPUs (or filtered according to the list found in the ISIM (EF_IMPU)). In other embodiments, the ME indicates that the registration was successful.
[0086] More specifically, referring to FIG. 16 , a flow diagram of a UICC receiving an IMS registration event is shown. To begin receiving IMS registration events, the UICC will verify the terminal profile for the ME support of this event. The mapping of the thirty first byte of the UICC is shown in FIG. 15 . The UICC registers the IMS registration event with the ME via a set up event list command.
[0087] More specifically, with the set up event list USAT command, the UICC uses this command to supply a set of events. This set of events becomes the current list of events for which the terminal is to monitor. Any subsequent set up event list command replaces the current list of events supplied in a previous set up event list command. The set up event list command can also be used to remove an entire list of events. The set up event list command can also be used to remove an entire list of events current in the terminal. The list of events provided by the UICC in the last set up event list command will be removed if the terminal is powered off or the UICC is removed or a reset is performed. When the terminal has successfully accepted or removed the list of events, the terminals sends a terminal response okay to the UICC. When the terminal is not able to successfully accept or remove the list of events, the terminal sends a terminal response of command beyond terminal's capabilities. When one of the events in the current list occurs, then the terminal uses an event download mechanism to transfer details of the event to the UICC.
[0088] For the event list byte coding, a plurality of values are defined in addition to those defined for 3GPP within TS 31.111. More specifically, the values can further include a byte value of 11 for an I-WLAN access status event, a value of 12 for a network rejection event, a value of 15 for a closed subscriber group (CSG) cell selection event and a placeholder value of 1y for IMS registration event where each event would receive a new value.
[0089] The ME then includes the IARIs of the supported applications on the UICC in the REGISTER request pursuant to 3GPP TS 24.229. The ME receives a 200 OK that contains the Private header associated uniform resource indicator (P-Associated-URI) list. A P-Associated-URI list allows a registrar to return a set of associated URIs for a register address of record.
[0090] The ME sends the IMS registration notification to the UICC containing the list of IMPUs based on the IMPUs included in the P-Associated-URI.
[0091] If the IMS Registration event is part of the current event list (as set up by the last set up event list command, then, upon receiving a 200 OK after a REGISTER SIP message, the terminal informs the UICC that this event has occurred, by using the ENVELOPE (EVENT DOWNLOAD—IMS Registration) command. The direction of the command is ME to UICC and the command header could be specified in 3GPP TS 31.111. Additionally, the structure of the ENVELOPE (EVENT DOWNLOAD—IMS Registration) command is set forth in Table 9.
[0000]
TABLE 9
Command parameters/data.
Description
Clause
M/O
Min
Length
Event download tag
9.1
M
Y
1
Length (A + B + (C or D or I) + E +
—
M
Y
1
F + G + H) + J
Event list
8.25
M
Y
A
Device identities
8.7
M
Y
B
IMPU lists
8.9X
M
Y
G
Event list: the Event list data object contains only one event (value part of length 1 byte), and terminal sets the event to:
IMS Registration Event.
Device identities: the terminal shall set the device identities to:
source: Network;
destination: UICC.
IMPU: This data object shall contain the list of IMPUs received in the 200 OK message in the P-Associated-URI header.
Response parameters/data: None for this type of ENVELOPE command.
[0092] Additionally, the registered IMPUs are set forth in Table 10.
[0000]
TABLE 10
Byte(s)
Description
Length
1
IMPU List Tag
1
2
Length
X
3
IMPU tag
Y
4
IMPU length
Z
. . .
.
. . .
.
.
. . .
. . .
. . .
Contents:
List of all the IMPUs received in the 200 OK message following the SIP REGISTER message.
Coding:
IMPU values are coded as defined in 3GPP TS 24.229.
[0093] Certain embodiments further include a feature of indicating to the UICC that the ME has registered with IMS after each notify indication. Once the ME has successfully registered with the IMS network, the ME indicates to the UICC that the registration was successful. In certain embodiments, the ME can give the UICC all IMPUs that have been registered. In other embodiment, the ME indicates that the registration was successful.
[0094] The UICC will verify the terminal profile for the ME support of this event. The mapping of one of the bytes of the terminal profile of the UICC is shown in FIG. 15 . With respect to this mapping, each new service is accorded a corresponding bit such as an incoming data bit or an IMS registration bit. In other embodiments, a service may be accorded both an incoming data bit and an IMS registration bit.
[0095] The UICC registers the IMS registration event with the ME via a set up event list command.
[0096] More specifically, with the set up event list USAT command, the UICC uses this command to supply a set of events. This set of events becomes the current list of events for which the terminal is to monitor. Any subsequent set up event list command replaces the current list of events supplied in a previous set up event list command. The set up event list command can also be used to remove an entire list of events. The set up event list command can also be used to remove an entire list of events current in the terminal. The list of events provided by the UICC in the last set up event list command will be removed if the terminal is powered off or the UICC is removed or a reset is performed. When the terminal has successfully accepted or removed the list of events, the terminals sends a terminal response okay to the UICC. When the terminal is not able to successfully accept or remove the list of events, the terminal sends a terminal response of command beyond terminal's capabilities. When one of the events in the current list occurs, then the terminal uses an event download mechanism to transfer details of the event to the UICC.
[0097] For the event list byte coding, a plurality of values are defined in addition to those defined for 3GPP within TS 31.111. More specifically, the values can further include a byte value of 11 for an I-WLAN access status event, a value of 12 for a network rejection event, a value of 15 for a CSG cell selection event and a placeholder value of 1z for IMS Registration event.
[0098] The ME then includes the IARIs of the supported applications on the UICC in the SIP REGISTER request pursuant to 3GPP TS 24.229. The ME receives a 200 OK that contains the P-Associated-URI list. The ME sends a SUBSCRIBE for the Registration event package. The ME receives a 200 OK message.
[0099] The ME then receives the initial SIP NOTIFY associated with the initial IMS registration event. The body of which includes a list of registered IMPUs and the <unknown param> field can contain media feature tags including the registered ICSI and registered IARI values. The ME sends a 200 OK and sends the IMS registration notification to the UICC.
[0100] If the IMS Registration event is part of the current event list (as set up by the last set up event list command, then, upon receiving the initial SIP NOTIFY after a SIP REGISTER message, the terminal informs the UICC that this event has occurred, by using the EVENLOPE (EVENT DOWNLOAD—IMS registration) command. The direction of the command is ME to UICC and the command header is specified in 3GPP TS 31.111. Additionally, the structure of the ENVELOPE (EVENT DOWNLOAD—IMS registration) command is set forth in Table 11.
[0000]
TABLE 11
Command parameters/data.
Description
Clause
M/O
Min
Length
Event download tag
9.1
M
Y
1
Length (A + B + (C or D or I) + E +
—
M
Y
1
F + G + H) + J
Event list
8.25
M
Y
A
Device identities
8.7
M
Y
B
IMPU lists
8.9X
M
Y
G
Event list: the Event list data object contains only one event (value part of length 1 byte), and terminal sets the event to:
IMS Registration Event.
Device identities: the terminal sets the device identities to:
source: Network;
destination: UICC.
IMPU: This data object contains the list of IMPUs received in the 200 OK message in the unknown-param element.
Response parameters/data: None for this type of ENVELOPE command.
[0101] Additionally, the registered IMPUs are set forth in Table 12.
[0000]
TABLE 12
Byte(s)
Description
Length
1
IMPU List Tag
1
2
Length
X
3
IMPU tag
Y
4
IMPU length
Z
. . .
.
. . .
.
.
. . .
. . .
. . .
Contents:
List of all the IMPUs received in the SIP NOTIFY message
Coding:
IMPU values shall be coded as defined in 3GPP TS 24.229.
[0102] FIG. 17 illustrates a wireless communications system including an embodiment of user agent (UA) 1701 . UA 1701 is operable for implementing aspects of the disclosure, but the disclosure should not be limited to these implementations. Though illustrated as a mobile phone, the UA 1701 may take various forms including a wireless handset, a pager, a personal digital assistant (PDA), a portable computer, a tablet computer, a laptop computer. Many suitable devices combine some or all of these functions. In some embodiments of the disclosure, the UA 1701 is not a general purpose computing device like a portable, laptop or tablet computer, but rather is a special-purpose communications device such as a mobile phone, a wireless handset, a pager, a PDA, or a telecommunications device installed in a vehicle. The UA 1701 may also be a device, include a device, or be included in a device that has similar capabilities but that is not transportable, such as a desktop computer, a set-top box, or a network node. The UA 1701 may support specialized activities such as gaming, inventory control, job control, and/or task management functions, and so on.
[0103] The UA 1701 includes a display 1702 . The UA 1701 also includes a touch-sensitive surface, a keyboard or other input keys generally referred as 1704 for input by a user. The keyboard may be a full or reduced alphanumeric keyboard such as QWERTY, Dvorak, AZERTY, and sequential types, or a traditional numeric keypad with alphabet letters associated with a telephone keypad. The input keys may include a trackwheel, an exit or escape key, a trackball, and other navigational or functional keys, which may be inwardly depressed to provide further input function. The UA 1701 may present options for the user to select, controls for the user to actuate, and/or cursors or other indicators for the user to direct.
[0104] The UA 1701 may further accept data entry from the user, including numbers to dial or various parameter values for configuring the operation of the UA 1701 . The UA 1701 may further execute one or more software or firmware applications in response to user commands. These applications may configure the UA 1701 to perform various customized functions in response to user interaction. Additionally, the UA 1701 may be programmed and/or configured over-the-air, for example from a wireless base station, a wireless access point, or a peer UA 1701 .
[0105] Among the various applications executable by the UA 1701 are a web browser, which enables the display 1702 to show a web page. The web page may be obtained via wireless communications with a wireless network access node 1719 , such as a cell tower, a peer UA 1701 , or any other wireless communication network or system 1700 . The network 1700 is coupled to a wired network 1708 , such as the Internet. Via the wireless link and the wired network, the UA 1701 has access to information on various servers, such as a server 1710 . The server 1710 may provide content that may be shown on the display 1702 . Alternately, the UA 1701 may access the network 1700 through a peer UA 1701 acting as an intermediary, in a relay type or hop type of connection.
[0106] FIG. 18 shows a block diagram of the UA 1701 . While a variety of known components of UAs 1701 are depicted, in an embodiment a subset of the listed components and/or additional components not listed may be included in the UA 1701 . The UA 1701 includes a digital signal processor (DSP) 1802 and a memory 1804 . As shown, the UA 1701 may further include an antenna and front end unit 1806 , a radio frequency (RF) transceiver 1808 , an analog baseband processing unit 1810 , a microphone 1812 , an earpiece speaker 1814 , a headset port 1816 , an input/output interface 1818 , a removable memory card 1820 , a universal serial bus (USB) port 1822 , a short range wireless communication sub-system 1824 , an alert 1826 , a keypad 1828 , a liquid crystal display (LCD), which may include a touch sensitive surface 1830 , an LCD controller 1832 , a charge-coupled device (CCD) camera 1834 , a camera controller 1836 , and a global positioning system (GPS) sensor 1838 . In an embodiment, the UA 1701 may include another kind of display that does not provide a touch sensitive screen. In an embodiment, the DSP 1802 may communicate directly with the memory 1804 without passing through the input/output interface 1818 . It will be appreciated that a UA which includes a memory card 1820 is generally referred to as a UE whereas a UA which does not include the memory card 1820 is generally referred to as a ME. In other words, a UE is the combination of an ME as well as a memory card.
[0107] The DSP 1802 or some other form of controller or central processing unit operates to control the various components of the UA 1701 in accordance with embedded software or firmware stored in memory 1804 or stored in memory contained within the DSP 1802 itself. In addition to the embedded software or firmware, the DSP 1802 may execute other applications stored in the memory 1804 or made available via information carrier media such as portable data storage media like the removable memory card 1820 or via wired or wireless network communications. The application software may comprise a compiled set of machine-readable instructions that configure the DSP 1802 to provide the desired functionality, or the application software may be high-level software instructions to be processed by an interpreter or compiler to indirectly configure the DSP 1802 .
[0108] The antenna and front end unit 1806 may be provided to convert between wireless signals and electrical signals, enabling the UA 1701 to send and receive information from a cellular network or some other available wireless communications network or from a peer UA 1701 . In an embodiment, the antenna and front end unit 1806 may include multiple antennas to support beam forming and/or multiple input multiple output (MIMO) operations. As is known to those skilled in the art, MIMO operations may provide spatial diversity which can be used to overcome difficult channel conditions and/or increase channel throughput. The antenna and front end unit 1806 may include antenna tuning and/or impedance matching components, RF power amplifiers, and/or low noise amplifiers.
[0109] The RF transceiver 1808 provides frequency shifting, converting received RF signals to baseband and converting baseband transmit signals to RF. In some descriptions a radio transceiver or RF transceiver may be understood to include other signal processing functionality such as modulation/demodulation, coding/decoding, interleaving/deinterleaving, spreading/despreading, inverse fast Fourier transforming (IFFT)/fast Fourier transforming (FFT), cyclic prefix appending/removal, and other signal processing functions. For the purposes of clarity, the description here separates the description of this signal processing from the RF and/or radio stage and conceptually allocates that signal processing to the analog baseband processing unit 1810 and/or the DSP 1802 or other central processing unit. In some embodiments, the RF Transceiver 1808 , portions of the Antenna and Front End 1806 , and the analog base band processing unit 1810 may be combined in one or more processing units and/or application specific integrated circuits (ASICs).
[0110] The analog baseband processing unit 1810 may provide various analog processing of inputs and outputs, for example analog processing of inputs from the microphone 1812 and the headset 1816 and outputs to the earpiece 1814 and the headset 1816 . To that end, the analog baseband processing unit 1810 may have ports for connecting to the built-in microphone 1812 and the earpiece speaker 1814 that enable the UA 1701 to be used as a cell phone. The analog baseband processing unit 1810 may further include a port for connecting to a headset or other hands-free microphone and speaker configuration. The analog baseband processing unit 1810 may provide digital-to-analog conversion in one signal direction and analog-to-digital conversion in the opposing signal direction. In some embodiments, at least some of the functionality of the analog baseband processing unit 1810 may be provided by digital processing components, for example by the DSP 1802 or by other central processing units.
[0111] The DSP 1802 may perform modulation/demodulation, coding/decoding, interleaving/deinterleaving, spreading/despreading, inverse fast Fourier transforming (IFFT)/fast Fourier transforming (FFT), cyclic prefix appending/removal, and other signal processing functions associated with wireless communications. In an embodiment, for example in a code division multiple access (CDMA) technology application, for a transmitter function the DSP 1802 may perform modulation, coding, interleaving, and spreading, and for a receiver function the DSP 1802 may perform despreading, deinterleaving, decoding, and demodulation. In another embodiment, for example in an orthogonal frequency division multiplex access (OFDMA) technology application, for the transmitter function the DSP 1802 may perform modulation, coding, interleaving, inverse fast Fourier transforming, and cyclic prefix appending, and for a receiver function the DSP 1802 may perform cyclic prefix removal, fast Fourier transforming, deinterleaving, decoding, and demodulation. In other wireless technology applications, yet other signal processing functions and combinations of signal processing functions may be performed by the DSP 1802 .
[0112] The DSP 1802 may communicate with a wireless network via the analog baseband processing unit 1810 . In some embodiments, the communication may provide Internet connectivity, enabling a user to gain access to content on the Internet and to send and receive e-mail or text messages. The input/output interface 1818 interconnects the DSP 1802 and various memories and interfaces. The memory 1804 and the removable memory card 1820 may provide software and data to configure the operation of the DSP 1802 . Among the interfaces may be the USB interface 1822 and the short range wireless communication sub-system 1824 . The USB interface 1822 may be used to charge the UA 1701 and may also enable the UA 1701 to function as a peripheral device to exchange information with a personal computer or other computer system. The short range wireless communication sub-system 1824 may include an infrared port, a Bluetooth interface, an IEEE 202.11 compliant wireless interface, or any other short range wireless communication sub-system, which may enable the UA 1701 to communicate wirelessly with other nearby mobile devices and/or wireless base stations.
[0113] The input/output interface 1818 may further connect the DSP 1802 to the alert 1826 that, when triggered, causes the UA 1701 to provide a notice to the user, for example, by ringing, playing a melody, or vibrating. The alert 1826 may serve as a mechanism for alerting the user to any of various events such as an incoming call, a new text message, and an appointment reminder by silently vibrating, or by playing a specific pre-assigned melody for a particular caller.
[0114] The keypad 1828 couples to the DSP 1802 via the interface 1818 to provide one mechanism for the user to make selections, enter information, and otherwise provide input to the UA 1701 . The keyboard 1828 may be a full or reduced alphanumeric keyboard such as QWERTY, Dvorak, AZERTY and sequential types, or a traditional numeric keypad with alphabet letters associated with a telephone keypad. The input keys may include a trackwheel, an exit or escape key, a trackball, and other navigational or functional keys, which may be inwardly depressed to provide further input function. Another input mechanism may be the LCD 1830 , which may include touch screen capability and also display text and/or graphics to the user. The LCD controller 1832 couples the DSP 1802 to the LCD 1830 .
[0115] The CCD camera 1834 , if equipped, enables the UA 1701 to take digital pictures. The DSP 1802 communicates with the CCD camera 1834 via the camera controller 1836 . In another embodiment, a camera operating according to a technology other than Charge Coupled Device cameras may be employed. The GPS sensor 1838 is coupled to the DSP 1802 to decode global positioning system signals, thereby enabling the UA 1701 to determine its position. Various other peripherals may also be included to provide additional functions, e.g., radio and television reception.
[0116] FIG. 19 illustrates a software environment 1902 that may be implemented by the DSP 1802 . The DSP 1802 executes operating system drivers 1904 that provide a platform from which the rest of the software operates. The operating system drivers 1904 provide drivers for the UA hardware with standardized interfaces that are accessible to application software. The operating system drivers 1904 include application management services (AMS) 1906 that transfer control between applications running on the UA 1701 . Also shown in FIG. 19 are a web browser application 1908 , a media player application 1910 , and Java applets 1912 . The web browser application 1908 configures the UA 1701 to operate as a web browser, allowing a user to enter information into forms and select links to retrieve and view web pages. The media player application 1910 configures the UA 1701 to retrieve and play audio or audiovisual media. The Java applets 1912 configure the UA 1701 to provide games, utilities, and other functionality. A component 1914 might provide functionality described herein.
[0117] The UA 1701 , base station 1720 , and other components described above might include a processing component that is capable of executing instructions related to the actions described above. FIG. 20 illustrates an example of a system 2000 that includes a processing component 2010 suitable for implementing one or more embodiments disclosed herein. In addition to the processor 2010 (which may be referred to as a central processor unit (CPU or DSP), the system 2000 might include network connectivity devices 2020 , random access memory (RAM) 2030 , read only memory (ROM) 2040 , secondary storage 2050 , and input/output (I/O) devices 2060 . In some cases, some of these components may not be present or may be combined in various combinations with one another or with other components not shown. These components might be located in a single physical entity or in more than one physical entity. Any actions described herein as being taken by the processor 2010 might be taken by the processor 2010 alone or by the processor 2010 in conjunction with one or more components shown or not shown in the drawing.
[0118] The processor 2010 executes instructions, codes, computer programs, or scripts that it might access from the network connectivity devices 2020 , RAM 2030 , ROM 2040 , or secondary storage 2050 (which might include various disk-based systems such as hard disk, floppy disk, or optical disk). While only one processor 2010 is shown, multiple processors may be present. Thus, while instructions may be discussed as being executed by a processor, the instructions may be executed simultaneously, serially, or otherwise by one or multiple processors. The processor 2010 may be implemented as one or more CPU chips.
[0119] The network connectivity devices 2020 may take the form of modems, modem banks, Ethernet devices, universal serial bus (USB) interface devices, serial interfaces, token ring devices, fiber distributed data interface (FDDI) devices, wireless local area network (WLAN) devices, radio transceiver devices such as code division multiple access (CDMA) devices, global system for mobile communications (GSM) radio transceiver devices, worldwide interoperability for microwave access (WiMAX) devices, and/or other well-known devices for connecting to networks. These network connectivity devices 2020 may enable the processor 2010 to communicate with the Internet or one or more telecommunications networks or other networks from which the processor 2010 might receive information or to which the processor 2010 might output information.
[0120] The network connectivity devices 2020 might also include one or more transceiver components 2025 capable of transmitting and/or receiving data wirelessly in the form of electromagnetic waves, such as radio frequency signals or microwave frequency signals. Alternatively, the data may propagate in or on the surface of electrical conductors, in coaxial cables, in waveguides, in optical media such as optical fiber, or in other media. The transceiver component 2025 might include separate receiving and transmitting units or a single transceiver. Information transmitted or received by the transceiver 2025 may include data that has been processed by the processor 2010 or instructions that are to be executed by processor 2010 . Such information may be received from and outputted to a network in the form, for example, of a computer data baseband signal or signal embodied in a carrier wave. The data may be ordered according to different sequences as may be desirable for either processing or generating the data or transmitting or receiving the data. The baseband signal, the signal embedded in the carrier wave, or other types of signals currently used or hereafter developed may be referred to as the transmission medium and may be generated according to several methods well known to one skilled in the art.
[0121] The RAM 2030 might be used to store volatile data and perhaps to store instructions that are executed by the processor 2010 . The ROM 2040 is a non-volatile memory device that typically has a smaller memory capacity than the memory capacity of the secondary storage 2050 . ROM 2040 might be used to store instructions and perhaps data that are read during execution of the instructions. Access to both RAM 2030 and ROM 2040 is typically faster than to secondary storage 2050 . The secondary storage 2050 is typically comprised of one or more disk drives or tape drives and might be used for non-volatile storage of data or as an over-flow data storage device if RAM 2030 is not large enough to hold all working data. Secondary storage 2050 may be used to store programs that are loaded into RAM 2030 when such programs are selected for execution.
[0122] The I/O devices 2060 may include liquid crystal displays (LCDs), touch screen displays, keyboards, keypads, switches, dials, mice, track balls, voice recognizers, card readers, paper tape readers, printers, video monitors, or other well-known input/output devices. Also, the transceiver 2025 might be considered to be a component of the I/O devices 2060 instead of or in addition to being a component of the network connectivity devices 2020 . Some or all of the I/O devices 2060 may be substantially similar to various components depicted in the previously described drawing of the UA 1701 , such as the display 1702 and the input 1704 .
[0123] While several embodiments have been provided in the present disclosure, it should be understood that the disclosed systems and methods may be embodied in many other specific forms without departing from the spirit or scope of the present disclosure. The present examples are to be considered as illustrative and not restrictive, and the intention is not to be limited to the details given herein. For example, the various elements or components may be combined or integrated in another system or certain features may be omitted, or not implemented.
[0124] As used herein, the terms “component,” “system” and the like are intended to refer to a computer-related entity, either hardware, a combination of hardware and software, software, or software in execution. For example, a component may be, but is not limited to being, a process running on a processor, a processor, an object, an executable, a thread of execution, a program, and/or a computer. By way of illustration, both an application running on a computer and the computer can be a component. One or more components may reside within a process and/or thread of execution and a component may be localized on one computer and/or distributed between two or more computers.
[0125] As used herein, the terms “user equipment” and “UE” can refer to wireless devices such as mobile telephones, personal digital assistants (PDAs), handheld or laptop computers, and similar devices or other user agents (“UAs”) that have telecommunications capabilities. In some embodiments, a UE may refer to a mobile, wireless device. The term “UE” may also refer to devices that have similar capabilities but that are not generally transportable, such as desktop computers, set-top boxes, or network nodes.
[0126] Furthermore, the disclosed subject matter may be implemented as a system, method, apparatus, or article of manufacture using standard programming and/or engineering techniques to produce software, firmware, hardware, or any combination thereof to control a computer or processor based device to implement aspects detailed herein. The term “article of manufacture” (or alternatively, “computer program product”) as used herein is intended to encompass a computer program accessible from any computer-readable device, carrier, or media. For example, computer readable media can include but are not limited to magnetic storage devices (e.g., hard disk, floppy disk, magnetic strips . . . ), optical disks (e.g., compact disk (CD), digital versatile disk (DVD). . . ), smart cards, and flash memory devices (e.g., card, stick). Additionally it should be appreciated that a carrier wave can be employed to carry computer-readable electronic data such as those used in transmitting and receiving electronic mail or in accessing a network such as the Internet or a local area network (LAN). Of course, those skilled in the art will recognize many modifications may be made to this configuration without departing from the scope or spirit of the claimed subject matter.
[0127] Also, techniques, systems, subsystems and methods described and illustrated in the various embodiments as discrete or separate may be combined or integrated with other systems, modules, techniques, or methods without departing from the scope of the present disclosure. Other items shown or discussed as coupled or directly coupled or communicating with each other may be indirectly coupled or communicating through some interface, device, or intermediate component, whether electrically, mechanically, or otherwise. Other examples of changes, substitutions, and alterations are ascertainable by one skilled in the art and may be made without departing from the spirit and scope disclosed herein. Although the present invention has been described in detail, it should be understood that various changes, substitutions and alterations can be made hereto without departing from the spirit and scope of the invention as defined by the appended claims. | To consolidate session initiation protocol (SIP) messages a user equipment (UE) is made aware of all Internet Protocol (IP) multimedia subsystem (IMS) applications installed in its memory and on a universal integrated circuit card (UICC) and supported communication services. By obtaining this information before the initial IMS Registration, the UE can save resources by registering all local applications and communication services in single IMS registration. | 7 |
PRIOR APPLICATION
This application is a U.S. national phase application that is based on and claims priority from International Application No. PCT/SE2010/050915, filed 25 Aug. 2010.
TECHNICAL FIELD
The present invention concerns impregnation of chips during the manufacture of chemical pulp.
BACKGROUND AND SUMMARY OF THE INVENTION
In conventional continuous cooking has a pre-treatment arrangement with a chip bin been used, in which a first heating of the chips by low pressure steam to a temperature of 70-100° C. is carried out. A steam-treatment in a steam vessel follows the pre-treatment in which the chips are intensely heated with flash steam and/or live low pressure steam to 110-120° C. The thoroughly steamed chips are then slurried in a chip chute before being fed to the cooking process. This process requires large quantities of steam as well a number of expensive treatment vessels adding cost and complexity into the cooking system.
The extensive steam treatment and its implementation in several treatment vessels has been considered to be totally necessary in order to be able ensure that air and water bound to the chips are expelled, such that the impregnation fluid can fully penetrate the chips and such that air is not drawn into the digestion process with the chips.
Attempts have been made to integrate the chip bin with the impregnation vessel such that a simple system is in this way obtained.
Metso Fiber Karlstad AB's U.S. Pat. No. 3,532,594 shows a combined vessel in which steam treatment and the formation of a slurry take place in a single pressure vessel that is maintained at an excess pressure of 1-2 atmospheres. The system was used in a pulp plant in Sweden as early as the 1970s. In this case, an impregnation fluid is recirculated during the addition of black liquor that maintains the suggested temperature of 105° C. in a circulation that consists of withdrawal strainer ( 35 )—pump ( 23 )—heat exchanger ( 25 )—outlet/central pipe ( 27 ). Steam flashed off from black liquor in a flash tank was also added in an additional central pipe together with an optional addition of fresh steam. The idea in this case was that all water vapour would be expelled through the superior bed of chips by steam, and that this water vapour could be withdrawn (ventilated) through the outlet 12 . A powerful heat exchanger ( 25 ) was required in this system. There is a serious risk of malodorous non-condensable gases (NCGs) leaking out, via the inlet 13 . It is also specified in this patent that it would be possible to remove totally the addition of steam and have only a reinforced indirect heating of the chips with the aid of a heating flow during the addition of black liquor. It is difficult to implement this heating technology since it requires very large recirculation flows and a large heating power in the heat exchanger in order to be able to heat the cold chips.
U.S. Pat. No. 5,635,025 shows a system in which chips are fed without a preceding steam treatment into a vessel in the form of a combined chip bin, impregnation vessel and chip chute. Steam treatment of the chips that lie above the fluid level takes place at this location by the addition of steam from a “steam source”, as does a simple addition of impregnation fluid in the lower part of the vessel.
U.S. Pat. No. 6,280,567 shows a further such system in which the chips are fed without preceding steam treatment into an impregnation vessel at atmospheric pressure where the chips are heated by the addition of hot black liquor that maintains a temperature of approximately 130-140° C. The hot black liquor is added just under the fluid level via pipes in the wall of the impregnation vessel and excess liquid is only drained from the slurry in an external steaming vessel.
SE 523850 shows an alternative system in which hot, pressurised black liquor taken directly from the digester at a temperature of 125-140° C. is added to the upper part of the steam-treatment vessel, above the fluid level but under the level of chips, whereby the black liquor whose pressure has been relieved releases large quantities of steam for the steam treatment of the chips that lie above the fluid level established in the vessel. Excess fluid, the black liquor, can in this case be withdrawn from the lower part of the vessel.
Thus, prior art technology has in most cases used steam treatment as a significant part of the heating of the chips, where the steam that is used is either constituted by fresh steam or by steam that has been obtained following pressure reduction of black liquor from the cooking step, the latter containing large amount of sulphur laden NCG gases. This ensures a relatively large flow of steam, with the associated consumption of energy, and it requires a steam-treatment system that can be controlled.
The steam treatment has also involved the generation of large quantities of malodorous gases, i.e. NCG gases, with a high risk of explosion at certain concentrations.
U.S. Pat. No. 7,381,302 (or U.S. Pat. No. 7,615,134) shows an arrangement in an attempt to avoid excessive volumes of steam flowing trough the chip bed. Impregnation fluids (BL 1 /BL 2 /BL 3 ) are in this case added with increasing temperatures at different positions (P 1 , P 2 , P 3 ) where the local pressure may be above the boiling point of the added liquor. Most of the volatile compounds in the black liquor added are bound to the withdrawn impregnation fluid (REC).
In SE 530725 (=US2009139671) is a further improvement of atmospheric impregnation vessels using hot black liquor shown. Here are knock down showers installed above the chip level in order to prevent blow trough of malodorous NCG gases.
It has surprisingly become apparent that the use of an atmospheric impregnation vessel, using hot alkaline black liquor for the major part of the steaming effect of chips, releases large quantities of wood acidity in the chips. In recent tests in impregnation of chips has as much as 1.5 m 3 /BDt wood of acidified liquid with no or neglectable residual alkali been withdrawn from early screen sections in the impregnation vessel. This large volume of acidified liquid with low residual alkali was found to have a distinct reddish terracotta colour quite different in colour than regular spent black liquor from alkaline cooks, as well as having a sticky malodorous scent. There are a number of possible cures for this situation, but most of them results in increased alkali losses in the withdrawn spent impregnation liquid. A problem associated with the low residual alkali level in the withdrawn spent impregnation liquid is that the chips close to the wall of the impregnation vessel, close to withdrawal position, are impregnated with the same liquid as last withdrawn from vessel. The chips close to the wall are thus not impregnated at requested alkaline conditions as the chips close to centre of impregnation vessel, which results in uneven impregnation conditions over the cross section of the vessel.
Another problem is that the released wood acidity brings about a dissolution of metal from the wood material due to acidic conditions, which content of metals is cumbersome for the subsequent process. Especially calcium has a tendency to form scaling in the equipment in form of calcium carbonate, said scaling activated by high temperature.
Yet another problem is that the large volumes of acidic fluid need a lot of alkali only for neutralization of the acidity. This creates further alkali consumption in the cooking process.
The principal aim of the present invention is to achieve an improved method and an improved system for the impregnation and heating of chips that have not been steam-treated, which method and system reduce the problems with formation of large volumes of acidic condensates during steaming.
A second aim is to reduce the amount of metals being brought into the cooking process early in the process, thus reducing the risk for scaling problems.
A third aim is to reduce the total alkali charge in the cooking process, such that a minimum amount of alkali is needed to neutralise the wood material after steaming.
A fourth aim is to establish even impregnation conditions at alkali conditions for the chips directly after steaming and preferably in the very same vessel as used for steaming.
The inventive method for the impregnation and steaming of chips during the manufacture of chemical pulp comprises following steps a to e;
Step a: chips are continuously fed without preceding steam treatment to the top of an impregnation vessel where impregnated chips are fed out from the bottom of the vessel. The chips are thus in the original state having its natural content of wood acidity.
Step b: hot impregnation fluid at a first temperature above the boiling point of the hot impregnation fluid is added to the impregnation vessel ( 3 ), via a pipe having the outlet end located below a chip level (CH LEV ) established in the impregnation vessel and at a distance from the walls of the impregnation vessel, preferably in the centre, such that steam is released into the chip volume for steaming the chips. The impregnation fluid thus has a temperature above the boiling point at the prevailing pressure established in the impregnation vessel, which will generate steam during pressure release inside the impregnation vessel.
Step c: the impregnation fluid added establishes a fluid level in the impregnation vessel and where the chip level lies at least 1-2 meters, preferably 3-5 meters, over the fluid level and where the pressure at the top of the impregnation vessel that is essentially at the level of atmospheric pressure, ±0.5 bar(g) preferably ±0.2 bar(g). These are conditions that guarantee a low temperature in the vessel for the impregnation vessel and a steam release trough the pile of chips for steaming effect.
Step d: that a withdrawal of a first impregnation fluid for a first use takes place from the vessel at the level of the fluid level, from a first withdrawal volume located behind a first screen row mounted in the wall of the impregnation vessel. This withdrawal will extract most of the early steam condensate.
Step e: according to the inventive method is also an additional withdrawal of a second impregnation fluid taking place from the vessel at a level below the first screen row, from a second withdrawal volume located behind a second screen row mounted in the wall of the impregnation vessel, said level below the first screen row not exceeding the diameter of the impregnation vessel, and wherein the second impregnation fluid at least in part is returned into the centre of the impregnation vessel which is of different use than the first use of the first impregnation liquid. This method using two screen rows and recirculation of the last withdrawn liquid at least in part to centre of vessel will enable withdrawal of the large volumes of acidified treatment fluid from treatment vessel, containing dissolved metal ions and wood extractives such as to turpentine etc., thus avoiding need for alkali for neutralisation of these wood acidity, and the subsequent circulation could establish an even alkali profile over the cross section of the impregnation vessel for an even impregnation process of the wood chips.
According to a preferred embodiment of the inventive method is the first use for being part in the liquor flow sent to recovery, and not being part of fluid returned into the centre of the impregnation vessel. As this acidified waste flow contains less valuable content, as of cellulose or hemicelluloses, for the alkaline cooking process it is beneficial for an early extraction of this acidified liquid volume. It could be merged with other black liquor flows and sent to the recovery boiler, or merged with other acidic waste liquors from the bleach plant for further appropriate recovery of chemicals or fibre content.
According to another preferred embodiment of the inventive method is the amount of hot impregnation fluid fed in to the impregnation vessel in association with the fluid level exceeding 3 tonnes per tonne of wood and at a temperature of the impregnation fluid in the interval 115-170° C., such that the temperature of the fluid-wood mixture that is established at the fluid level is established within the interval 90-115° C., preferably within the interval 95-105° C., and where the level of alkali of the added impregnation fluid exceeds 15 g/l EA as NaOH. These amounts of hot alkaline liquor would supply all or most of the steam and alkali needed for the impregnation process.
According to yet another preferred embodiment of the inventive method is the amount of second impregnation fluid withdrawn exceeding 0.5 tonnes per tonne of wood and at least a part of this withdrawn second impregnation fluid is recirculated back to the centre of the impregnation vessel. Preferably could as much as 1.0 to 2.0 tonnes be withdrawn, and larger flows will establish a stronger circulation rate.
From this withdrawn amount could a part of the second impregnation fluid be returned into the centre of the impregnation vessel, and preferably at least 0.5 tonnes per tonne of wood. So if in total 0.5 tonnes is withdrawn could the entire volume be returned, and if in total 1.0 tonnes is withdrawn could half the volume be returned, hence always at least a part of the total amount is withdrawn and returned into the centre of the impregnation vessel.
According to yet a preferred embodiment of the inventive method could a part of the second impregnation fluid returned into the centre of the impregnation vessel be diluted with additional liquid. This additional liquid is preferably an alkaline wash filtrate from subsequent cooking or bleaching stages having a residual alkali content.
Further the total volume of second impregnation fluid, including any dilution, is preferably returned into the centre of the impregnation vessel below the first screens, and an upwardly directed displacement flow is established towards the first screens. The upwardly directed displacement flow will improve wash out effect of the acidic rest fluids from the preceding steaming effect, and further improve an even alkali profile in the subsequent impregnation process.
The inventive system used for impregnating and steaming chips in one single impregnation vessel during the manufacture of chemical pulp comprises following features. Said impregnation vessel having an inlet at the top for chips and an outlet in the bottom for impregnated chips. Said impregnation vessel having means for adding hot impregnation fluid at a first temperature above the boiling point of the hot impregnation fluid to the impregnation vessel, via a first central pipe having the outlet end located below a chip level established in the impregnation vessel and at a distance from the walls of the impregnation vessel, said outlet end preferably located in the centre, such that steam is released into the chip volume for steaming the chips. Said impregnation vessel further having means for establishing a fluid level by the added impregnation fluid in the impregnation vessel. And further having means for establishing a chip level lying at least 1-2 meters, preferably 3-5 meters, over the fluid level. The impregnation vessel further includes means for establishment of a pressure at the top of the impregnation vessel that is essentially at the level of atmospheric pressure, ±0.5 bar(g) preferably ±0.2 bar(g). Said impregnation vessel having a first screen row at the level of the fluid level comprising a first withdrawal volume located behind the first screen row mounted in the wall of the impregnation vessel for withdrawing spent impregnation fluid.
The inventive system further comprises an additional second screen row located in the impregnation vessel at a level below the first screen row, having a second withdrawal volume located behind the second screen row mounted in the wall of the impregnation vessel. Said level below the first screen row not exceeding the diameter of the impregnation vessel. And further a second withdrawal pipe connected to the second withdrawal volume for extracting spent treatment liquid, and wherein the second withdrawal pipe is connected to a second central pipe having an outlet in the impregnation vessel at a distance from the wall of the impregnation vessel and preferably in the centre of the impregnation vessel.
According to a preferred embodiment of the inventive system is the outlet of the second central pipe located below the first screen row. By having the first and second central pipes arranged at different levels could each central pipe be used to optimize either steam generation, as to the first central pipe, or improved circulation for evening out the alkali profile, as to the second central pipe. In some solutions however could only one single central pipe be used adding a mixed flow of hot impregnation fluid and recirculation fluid.
According to yet a preferred embodiment of the inventive system is a source of dilution liquid connected to the piping ( 43 , 41 c ) ending up into the outlet of the central pipe. By adding such source of dilution liquid could enhanced wash-out performance and a more even alkali profile be obtained.
The inventive withdrawal screen section for use in pre-treatment of chips in a liquor-vapour phase treatment vessel having a vapour phase in the top and a liquid phase in the bottom of said vessel comprises following components. Said withdrawal screen comprising, a first screen row mounted in the wall of the treatment vessel and in contact with chips drenched in treatment liquid inside the treatment vessel. Further a first withdrawal volume arranged outside of the first screen row collecting treatment liquid withdrawn from the treatment vessel via said first screen row as well as a first withdrawal pipe connected to the first withdrawal volume for extracting spent treatment liquid via a first pump. The inventive modification comprises further
an additional second screen row arranged at a level below the first screen row, a second withdrawal volume arranged outside of the second screen row collecting treatment liquid withdrawn from the treatment vessel via said second screen row, a second withdrawal pipe connected to the second withdrawal volume for extracting spent treatment liquid via a second pump (P 2 ), said level below the first screen row not exceeding the diameter of the impregnation vessel, and wherein the second withdrawal pipe is connected to a second central pipe having an outlet in the impregnation vessel at a distance from the wall of the impregnation vessel and preferably in the centre of the impregnation vessel.
In a preferred embodiment of the withdrawal screen is the outlet of the second central pipe located below the first screen row.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a prior art 2-vessel continuous cooking system with a first atmospheric impregnation vessel;
FIG. 2 shows a withdrawal screen section in the atmospheric impregnation vessel according to the invention;
FIG. 3 shows a 2-vessel continuous cooking system using the inventive withdrawal screen section;
FIG. 4 shows the pH profile established in the impregnation vessel at different heights using the invention; and
FIG. 5 shows an alternative embodiment of FIG. 2 with addition of dilution liquid to the second lower circulation.
DETAILED DESCRIPTION OF THE INVENTION
Definitions
The concept “untreated chips” will be used in the following detailed description. “Untreated chips” is here used to denote chips that have not passed through any form of steam treatment or similar, before the chips are fed into an impregnation vessel to be impregnated.
The concepts “fluid level/LIQ LEV ” and “chips level/CH LEV ” will also be used. The term “fluid level/LIQ LEV ” is here used to denote the level that the impregnation fluid added to the impregnation vessel 3 has established in the vessel. The term “chips level/CH LEV ” is here used to denote the height of that part of the bed of chips (consisting of chips) that is located above the fluid level, LIQ LEV .
Prior Art System, Starting Point for Invention
FIG. 1 shows an arrangement known per se for the impregnation of chips during the manufacture of chemical pulp. The arrangement comprises an essentially cylindrical impregnation vessel 3 arranged vertically, to which non-steamed chips are continuously fed to the top of the impregnation vessel through a feed arrangement, in the form of a conveyor belt 1 , and a sluice feed/chip feed 2 . When operating the impregnation vessel in the “cold top” mode the temperature at the top of the vessel 3 would essentially correspond to ambient temperature, or slightly above ambient temperature, i.e. up to 20° C. above ambient temperature, but with no active heating of the chips before being fed to the impregnation vessel. A slightly higher temperature than current ambient temperature could be established if for instance the chips are fed from a chip pile where a certain exothermic reaction occurs in the chip pile, or where the chip pile establish some insulation effect which may prevent the same low temperature as that prevailing in the ambient atmosphere.
In some installations in cold climate zones the temperature in the top of the impregnation vessel could lie at some −2° C. while the current ambient temperature is −20° C. In other installations in warm climate zones the temperature in the top of the impregnation vessel could lie at some +35° C. while the current ambient temperature is +30° C.
Additional fresh steam ST may be added if the ambient temperature falls below normal ambient temperature and in such a quantity that a chip temperature within this interval is established. The chips that are fed to the impregnation vessel normally maintain the same temperature as the ambient air temperature or slightly above, i.e. in the range from ambient up to 20° C. above ambient temperature. The chips fed in establish a chips level CH LEV in the upper part of the impregnation vessel.
A feed line 41 with hot impregnation fluid BL is connected to the impregnation vessel in order to establish a fluid level, LIQ LEV , consisting of the said impregnation fluid and controlled by level sensor 20 and associated valve in feed line 41 . The impregnation fluid is fed in directly in association with the fluid level, LIQ LEV , ±1 meter. The impregnation fluid BL is added at a distance from the wall of the impregnation vessel 3 , and preferably at the centre of the impregnation vessel. The impregnation fluid BL is fed in to the impregnation vessel in such an amount and at such a temperature that the temperature at the fluid level, CH LEV , is established within the interval 90-115° C. and preferably within the interval 95-105° C., whereby evaporation of fluid takes place up into the bed of chips lying above the fluid level, while at the same time steam is not driven through the bed of chips if operating in the cold top mode. The evaporation up into the bed of chips takes place over a distance that preferably does not exceed half of the height of the chips level, CH LEV .
The feed line 41 could forward the hot and partially spent hot cooking liquor withdrawn from digester directly to the impregnation vessel.
Alternatively the partially spent hot cooking liquor withdrawn from digester could be added first to bottom of impregnation vessel and mixed with the impregnated pulp before being fed via line 13 a / 13 b to the top separator 52 , and then the liquid withdrawn could be added via the central pipe 41 d . This method is called Crosscirc™ and promoted by Metso Paper, and implemented in order to save steam for heating in top of digester, as the hot liquid is first used for elevating the temperature of the chips already in the transfer system.
The impregnation fluid BL added is constituted to more than 50% by hot cooking fluid withdrawn from a screen SC 3 after use in a cooking zone in a subsequent digester 6 , which impregnation fluid BL has an alkali level of at least 15 g/l. The amount of impregnation fluid BL that is added to the vessel 3 lies between 5-10 m 3 /ADT, preferably between 7-9 m 3 /ADT, where “ADT” is an abbreviation for “Air-dry tonne” of pulp.
The temperature of the impregnation fluid BL in the feed line 41 maintains a temperature of 115-150° C. and the chips level CH LEV lies at least 1-2 meters over the fluid level and preferably 3-5 meters over the fluid level LIQ LEV , in order to facilitate drenching of the chips down into the impregnation fluid, where the chips are thoroughly impregnated. The weight from the chip volume above the fluid level assists in drenching the chips even if some residual air may be caught in the chips.
Given non-steam treated chips that maintain 25° C. with their naturally occurring moisture level, 5 tonnes of fluid that maintains 139° C. are required in order to establish a temperature of approximately 115° C. in the chips mixture at the fluid level. If a temperature of 100° C. is to be established in the chips mixture, given the same basic conditions, 5 tonnes of impregnation fluid that maintains 120° C. is required.
By adding the hot impregnation fluid in association with the fluid level CH LEV , most if not all the air present in the chips will be flashed out, and the chips will sink in the impregnation fluid.
A line 42 withdraws spent impregnation fluid and steam condensate, i.e. REC 2 , from withdrawal screen SC 1 in the impregnation vessel 3 , at the level of the fluid level LIQ LEV .
The pressure in the vessel can be adjusted as required through a regulator valve arranged in a ventilation line (not shown) at the top of the impregnation vessel. The ventilation line may open directly into the atmosphere, for the establishment of atmospheric pressure. It is preferable that a pressure at a level of atmospheric pressure is established, or a slight negative pressure down to −0.2 bar(g) (−20 kPa), or a slight excess pressure up to 0.2 bar(g) (20 kPa).
If necessary, an addition of a ventilating flow (sweep air) may be added at the top, which ventilating flow ensures the removal of any gases. However, this is not to be normally necessary during established operation.
The impregnated chips are continuously fed out through output means, here in the form of an outlet with two pumps 12 a and 12 b , combined where relevant with a bottom scraper 4 , at the bottom of the impregnation vessel 3 . The impregnated chips are thereafter fed to a top separator 51 arranged in the top of a continuous digester vessel 6 . The top separator 51 is here shown as an inverted top separator comprising an upwardly feeding screw 52 that feed the chip slurry passed a top separator screen SC 2 , withdrawing excess impregnation liquid. The drained chips thereafter falls down into the digester vessel 6 and new fresh cooking WL liquor is added. Full cooking temperature is established in the digester either by adding steam or using heating circulations (not shown). According to established practice is most of the fresh cooking WL added to the digester, i.e. 50% or more, and in this example shown as a charge to the top of the digester. As full cooking temperature is established in the cooking zone is the alkali consumption rather high in first stages of delignification, but slows down in bulk and residual delignification stages.
As indicated in previous parts is a hot cooking liquor with a substantial residual alkali level withdrawn via screen SC 3 and at least a part of this volume is used as the hot impregnation liquid in the impregnation vessel, either directly or via first usage according to Crosscirc™ as mentioned in previous parts. This position is typically in first half part of the cooking zone or at the end of this part. Here the delignification process has slowed down after the first cooking stage where alkali consumption is high. Thus, for subsequent delignification stages the need for residual alkali is substantially lower than first cooking stage.
In a conventional manner is the cook in the digester 6 ended by a wash zone, comprising dilution nozzles DL for adding wash liquid, typically brown wash filtrate BWF, and a withdrawal screen SC 4 , where the added wash liquid will displace the hot spent cooking liquor in flow REC 1 . As colder wash liquid is used, typically brown wash filtrate holds a temperature of 70-100° C., is the withdrawn hot spent cooking liquor REC 1 holding a temperature somewhat lower than full cooking temperature, but still with a residual heat content. As shown in FIG. 1 is this residual heat content utilised to heat the fresh cooking liquor WL in a heat exchanger, but after passage of such heat exchanger could the temperature still be well above 100° C.
The Invention
FIG. 2 shows an inventive design of the withdrawal screen SC 1 as implemented in a system shown in FIG. 1 . Thus, other common features are not described if already described in connection with FIG. 1 . Here is shown a vertical cross section of the impregnation vessel 3 , with the established liquid level, LIQ LEV , and the chip level, CH LEV , forming a chip volume with height HO above the liquid level. The control means for maintaining set levels use a conventional Digital Control System, DCS, receiving sensor inputs from level sensors A and B respectively as well as a temperature measuring pole TP, controlling in- and outflow of chips, as well as steam and added liquids. As shown here is the hot impregnation liquid added via a central pipe 41 d , and steam BL ST flash out from the liquor BL LIQ as it leaves the outlet of the central pipe.
A first screen row SC 1 a with a first withdrawal volume 60 b is located at the level of the fluid level, LIQ LEV . At least one first withdrawal pipe 42 is connected to said first withdrawal volume below the fluid level with means, here shown as a pump P 1 , for withdrawing liquid from the first withdrawal volume.
According the invention is an additional second screen row SC 1 b is located in the impregnation vessel at a level below the first screen row, having a second withdrawal volume 60 c located behind the second screen row mounted in the wall of the impregnation vessel, said level below the first screen row not exceeding the diameter of the impregnation vessel. A second withdrawal pipe 43 connected to the second withdrawal volume for extracting spent treatment liquid RET, and wherein the second withdrawal pipe is connected to a second central pipe 41 c having an outlet in the impregnation vessel at a distance from the wall of the impregnation vessel and preferably in the centre of the impregnation vessel
Further, as shown could also at least one additional feed pipe 70 for fresh low pressure steam and/or flash steam be connected to a steam distribution volume 60 a above the fluid level via a control valve.
In FIG. 3 is shown a digester system having the two sets of withdrawal screens SC 1 a and SC 1 b respectively in the impregnation vessel, and how the liquid flows are handled in the system. Here is shown how the entire amount of withdrawn treatment fluid from second withdrawal screen SC 1 b via central pipe 41 c , while the entire amount of withdrawn treatment fluid from first withdrawal screen SC 1 a is sent to recovery.
In FIG. 4 is the alkali profile obtained while using an inventive arrangement with two sets of withdrawal screens SC 1 a and SC 1 b respectively in the impregnation vessel, and following indicators are used:
CH LEV (unbroken line): shows the pH/alkali level at the surface of the chip level before the chips being exposed to any steaming effect. Here it is indicated that the pH level is about neutral over the entire cross section; LIQ LEV (unbroken line): shows the pH/alkali level at the liquid level, i.e. when the acidic condensates have been brought down with the steamed chips. The pH level could easily reach down to about pH4 over the entire cross section. The pH drop is about the distance A in figure, i.e. a drop in pH by about 3-4 units; SC 1 a (hatched line): shows the pH/alkali level after the first withdrawal screen SC 1 a , i.e. when the added hot alkaline treatment liquid has been added to centre and a withdrawal of the acidified treatment liquors has been made. The pH level could be quite high in centre in comparison to the alkali level close to the wall/screen. But the pH at the wall has been raised a distance B in figure by this withdrawal. SC 1 b (dotted line): shows the pH/alkali level after the second withdrawal screen SC 1 b , i.e. Due to the improved circulation has the pH/alkali level been levelled out such that the pH at the wall has been raised a distance C in figure and the previous high pH level in centre has been reduced a distance D in figure. The established pH profile is thus made more even over the cross section enabling a uniform impregnation process in subsequent impregnation phase in the impregnation vessel.
The pH profiling in FIG. 4 is schematic and show the principles.
If implemented in an impregnation vessel for softwood could as much as 1.5 ton/ton wood of acidified treatment fluid be withdrawn from first withdrawal screen, while 1.0 to 1.5 ton/ton wood of treatment fluid is withdrawn from second withdrawal screen and added back to chip volume by a central pipe. The pH profiling in such an example would reassemble the pH profiling shown in FIG. 4 to a great extent.
If an even pH profiling or reduction of alkali losses should be made following adjustments could be considered;
The amount of acidified treatment fluid withdrawn from first withdrawal screen could be optimised by controlling the pH of this flow. This could also be monitored visually simply by observing the colour in this liquor. When the reddish colour turns brown is the break point crossed for maximum amount of acidified liquor withdrawn. If more liquid is withdrawn then alkali losses would increase. As indicated above, as much as 1.5 tonne of reddish fluid could be withdrawn in this position for softwood. The amount of treatment fluid withdrawn from second withdrawal screen and recirculated back could be optimised by controlling the pH or residual alkali of this flow. The volume of fluid circulated could easily be increased as long as the pH level show an increase as a response to increased volumes recirculated. In this early position of the impregnation vessel it is easy to withdraw liquids as the chip pile is not yet started to be compacted by the delignification. In an established process this will be a trade off between increased pumping effect vs improved alkali profile. The alkali losses could be optimised by controlling additional liquid added to the flow recirculated back from the second withdrawal screen. Any additional liquid added could decrease the peak level of pH at centre proportional to amount added. Of course first added amounts would decrease more than last amounts added. In general is alkali profile even out as a function of increased recirculation volumes from second withdrawal screen.
In FIG. 5 is shown an alternative system according to FIG. 2 , but where additional liquid ADD LIQ is added to the recirculation volumes from second withdrawal screen. This additional liquid ADD LIQ could preferably be obtained from flows REC 1 or REC shown in FIG. 3 .
The invention is not limited to the embodiments shown. Several variants are possible within the framework of the claims.
While the present invention has been described in accordance with preferred compositions and embodiments, it is to be understood that certain substitutions and alterations may be made thereto without departing from the spirit and scope of the following claims. | The method, system and a withdrawal screen section are for the impregnation of chips during the manufacture of chemical pulp. Chips are both steamed and impregnated in a low pressure impregnation vessel, using pressurized hot spent cooking liquor BL as the main part of the impregnation liquid. The hot spent cooking liquor produces most of the steam BL ST necessary for steaming the chips. At least two independent first and second screen rows, SC 1 and SC 1 b respectively, are installed in order to improve the process in the impregnation vessel. The first screen row withdraws acidified treatment liquor for disposal which otherwise would be a parasitic acidified waste fluid in the system. The second screen row recirculates treatment fluid back to center of treatment vessel in order to even out the pH profile over the cross section of the vessel. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
“Not Applicable”
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
“Not Applicable”
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX
“Not Applicable”
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention is a silhouette target for use in live-fire tank gunnery practice. This invention is a free-standing target silhouette which will not be easily destroyed by the large-caliber projectiles fired through it.
2. Discussion of Prior Art
The basic method for constructing a large target silhouette for use in tank gunnery practice is to use ½″, or thicker, 4′×8′ sheets of plywood or particle board supported by 2″×4″ or 4″×4″ framing lumber. The 4′×8′ sheets of plywood are cut and assembled downrange near the target lifting mechanism and nailed or screwed to the framing lumber. The vertical supports of 2″×4″ or 4″×4″ lumber are attached to a lifting mechanism, positioned behind a protective berm, that rotates the target silhouette into the exposed upright position above the berm.
A full-scale frontal tank silhouette is approximately 12′ wide and 8′ high and weighs nearly 200 lbs. The actual weight depends on the panel thickness and the length of the vertical supports. The vertical supports are needed to add strength to the plywood panels and to raise the target silhouette above the protective earth mound in front of the target lifting mechanism. With a long lever arm (vertical support length) the torque required to rotate the target becomes very large (200 lbs.×6′=1200 ft-lb., for example) and a large and powerful lifting mechanism is required.
Examples of heavy rigid targets requiring substantial lifting mechanisms are shown in U.S. Pat. No. 5,403,017 “Target Lifter with Impact Sensing” by Doss, III, et al. and in U.S. Pat. No. 4,330,129 “Light Duty Target Support Apparatus” by Meredith.
A serious limitation of the present technique is the durability of the target and vertical supports. A few well-placed shots from a 120 mm gun can shatter the vertical supports and destroy the target. Another limitation is the excessive fabrication time, as well as the time for the frequent repairs, which require several men to handle the heavy materials involved in the process. The range down-time required to build and repair targets used in gunnery practice reduces the amount and effectiveness of range time available for training.
3. References of Prior Art
The following list of patents is given as reference for known prior practices.
3,733,073
May 1973
Gutler
4,119,317
October 1978
Ohlund, et al.
4,232,867
November 1980
Tate, Sr.
4,260,160
April 1981
Ejnell, et al.
4,330,129
May 1982
Meredith
4,405,132
September 1983
Thalmann
4,799,688
January 1989
Kellman, et al.
4,946,171
August 1990
Merle, et al.
5,065,032
November 1991
Prosser
5,403,017
April 1995
Doss, III, et al.
SUMMARY OF THE INVENTION
The main object of this invention is to provide a large, lightweight, self-supporting, full-scale tank-target silhouette using sheet material which is corrugated along the horizontal direction to form vertical ridges and grooves, similar to the construction of an accordion-folded door.
Another object of the invention is to provide a structurally-rigid target silhouette which is formed by clamping the corrugated target material along the bottom edge of the vertical ridges and grooves with a target holder mechanism that maintains the cross-sectional corrugated shape and that can be rotated backward and forward to lower and raise the target into the firing position.
Another object of the invention is to provide a tank target without structural upright supports which is capable of withstanding multiple hits from the 120 mm large-caliber main gun of the tank during gunnery practice.
Another object of the invention is to provide a lightweight folded target which can be transported easily to the target area, unfolded, and installed in the target holder in a few minutes by one man.
Another object of the invention is to provide a full-scale tank-target silhouette which is lightweight enough to reduce the size and power of the drive mechanism required to raise and lower the target.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric drawing of the frontal view of the tank-target silhouette comprised of corrugated target material (with vertically-aligned ridges and grooves) which is clamped into, and held upright by, a bottom clamping and support beam.
FIG. 2 is an isometric drawing showing the frontal view of the preferred embodiment of the tank-target silhouette and the bottom clamping and support beam attached to a typical lifting mechanism comprised of a mounting support frame, support arms with bearings, and a linear-actuator drive mechanism.
FIG. 3 is an exploded view of the tank-target silhouette assembly of FIG. 1 , showing the corrugated target silhouette and the bottom clamping and support beam.
FIG. 4 is a typical cross-sectional view of the preferred embodiment of FIG. 2 , detached from the lifter mechanism and without the corrugated target material, that shows the clamping and support beam in the closed, or clamped, position.
FIG. 5 is a typical cross-sectional view of the preferred embodiment of FIG. 2 , detached from the lifter mechanism and without the corrugated target material, that shows the clamping and support beam in the open, or unclamped, position.
FIG. 6 is a top view of the preferred embodiment of FIG. 2 that shows a small section of the accordion-folded silhouette with the clamping and support beam in the closed, or clamped, position and a typical toggle clamp.
DETAILED DESCRIPTION OF THE INVENTION
The proposed invention is based on the principle that thin-gauge, lightweight materials such as corrugated cardboard or extruded, ribbed-plastic sheet material gain structural strength when folded in a corrugated or accordion shape and are then clamped along one edge defined by the ridges and grooves of the corrugations. FIG. 1 shows the corrugated tank-target assembly 1 that is described in detail below and includes the corrugated target material 2 and the clamping and support beam assembly 3 that entraps and supports the bottom edge of the target corrugations.
The preferred embodiment of the invention is shown in FIG. 2 through FIG. 6 . In FIG. 2 the large full-scale corrugated tank-target assembly 1 is formed when thin-gauge material 2 (such as extruded polypropylene sheet material sold under trade names as “Coroplast,” Stratocore,” and “Plasticor”) is folded along the interior flutes of the extrusions in the vertical direction and then is firmly clamped along the bottom edge in the clamping and support beam assembly 3 . The width of the clamping and support beam assembly 3 for a normal-sized frontal tank-target is 12′. The height of the corrugated target silhouette 2 is nominally 8′, but could extend to 10′ or more, depending on how much of the target is exposed above a protective earthen berm.
Also shown in FIG. 2 is the support frame and lifting mechanism 4 of structural steel or aluminum channel pieces welded to form a rigid framework that supports the rotating, clamped, corrugated tank-target assembly 1 . Welded to the framework 4 are two pivot support arms 5 and 6 that attach to the clamping and support beam assembly 3 through two pivot-point bearing plates 7 and 8 around which the entire corrugated tank-target assembly 1 rotates. The 90° rotation of the corrugated tank-target assembly 1 is powered by a linear actuator 9 that pushes and pulls against a 6″-offset lever-arm plate 10 that forces the entire corrugated tank-target assembly 1 to rotate around the pivot points of plates 7 and 8 .
FIG. 3 , FIG. 4 , and FIG. 5 show additional details for the clamping and support beam assembly 3 . As shown in FIG. 3 , which is an exploded view of the corrugated tank-target assembly 1 of FIG. 1 , the clamping and support beam assembly 3 consists of two detachable parts: the support beam assemble 11 and the hinged clamping beam assembly 12 . Each of the beam assemblies 11 and 12 is shown in the preferred split configuration where the support beam assembly 11 and the hinged clamping beam assembly 12 are each half the final overall width of the clamping and support beam assembly 3 . During installation the halves of the support beam assembly 11 are bolted together at the center using the welded aluminum 6″-offset lever-arm end plates 10 which also provide the pivot point for the linear-actuator drive mechanism 9 . The two halves of the hinged clamping beam assembly 12 are assembled separately by connecting half the hinged clamping beam assembly 12 at a time to the support beam assembly 11 using hinges 18 .
FIG. 4 is a typical cross-sectional view of the preferred embodiment of FIG. 2 , detached from the support frame and lifter mechanism 4 and without the corrugated target material 2 installed, that shows the clamping and support beam assembly 3 in the closed, or clamped, position. FIG. 5 shows the same clamping and support beam assembly 3 of the preferred embodiment of FIG. 2 in the open, or unclamped, position. As shown in FIG. 4 and in FIG. 5 the clamping and support beam assembly 3 consists of a structural support beam assembly 11 and a clamping beam assembly 12 . The structural support beam 11 is a welded assembly consisting of aluminum channel pieces 13 , bent aluminum clamping rods 14 , and a ¼″-thick aluminum structural plate 15 that runs the length of the support beam assembly 11 . The aluminum channel is typically 2½″×1″×¼″ of appropriate length. The bent aluminum clamping rods 14 are typically ⅜″ diameter and of sufficient number to clamp every other vertical fold, or groove, in the corrugated target material 2 .
Again referring to FIG. 4 and to FIG. 5 , the hinged clamping beam assembly 12 is a welded assembly, similar to that of the support beam assembly 11 described above, employing the same type aluminum channel pieces 13 . The clamping beam assembly 12 is attached to the support beam assembly 11 by a series of slide-off hinges 18 that are attached to the respective assemblies. The 2-piece slide-off hinges have the socket-half of the hinges 18 welded to the structural plate 15 on the support beam assembly 11 . The pin-half of the hinges 18 are welded to the aluminum channel of the hinged clamping beam assembly 12 . Each half of the clamping beam assembly 12 is fitted with two toggle clamps 16 that have hook-type arms 17 that pass through small cut-outs in the corrugated target material 2 and engage the top channel 13 of the support beam assembly 11 . When closed, the toggle clamps provide the clamping force to securely hold the corrugated target material 2 in the clamping and support beam assembly 3 .
Refer now to FIG. 6 which shows a top view, View-A, of a small section of the corrugated target material 2 and the clamping and support beam assembly 3 in the clamped position for the preferred embodiment of FIG. 2 . FIG. 6 shows the corrugated target material 2 firmly clamped by the bent clamping rods 14 and the toggle clamp 16 with hook 17 between the support beam assembly 11 and the hinged clamping beam assembly 12 .
In practice, to replace a target silhouette, a new folded target silhouette 2 , which collapses to a bundle approximately 12″ W×4″ D×96″ H in size when folded and which weighs less than 50 lbs., is carried downrange to a target lifting mechanism 4 with clamping and support beam assembly 3 already installed. As described above, the toggle clamps 16 with hook 17 are loosened, the hinged clamping beam assembly 12 is opened, and the old target silhouette 2 is removed. The new collapsed corrugated target silhouette 2 is unfolded and installed into the support beam assembly 11 and then the clamping beam assembly 12 is hinged closed and clamped by the toggle clamps 16 .
It is understood that many other methods and materials can be used to form the clamping and support assembly 3 described above. For example, the bottom support assembly could be constructed using an epoxy/fiberglas molding technique with molds designed to match the saw-tooth pattern of the accordion folds of the target silhouette. The hollow fiberglas pieces that would be formed by this technique would then be filled with structural foam to form lightweight rigid clamping members which would be hinged and clamped in a manner similar to the aluminum-channel method described above in the preferred embodiment. It is also envisioned that the bottom of the corrugated target could be held in place by inserting two small tubes, or pipes, through holes in the corrugations across the width of the target silhouette and clamping the tubes to form a rigid dual-rail structure on which the silhouette is held in place. | This invention is a new-type, full-scale, tank-target silhouette for use in tank gunnery practice with the main gun of a tank. The new target employs lightweight sheet material that is corrugated in the manner of an accordion-door (or pleated) configuration to produce a self-supporting, rigid target silhouette which can be raised and lowered, and which can sustain multiple hits without collapsing. The corrugation configuration, when clamped along the bottom edge of the ridges and grooves, provides the necessary rigidity for the target to stand upright without other vertical structural members which could be hit and destroyed. | 5 |
FIELD OF THE INVENTION
[0001] This invention relates to the field of light emitting device, and in particular to the manufacture of light emitting devices (LEDs) with reduced epi stress.
BACKGROUND OF THE INVENTION
[0002] As the light emitting capabilities of Light Emitting Diodes (LEDs) continues to improve, their use in conventional lighting applications continues to increase, as do the competitive pressures to provide reliable, long-lasting products in a cost-effective manner. Even though the cost of LED products is relatively low, the savings of even a few cents per device can have a significant impact on profit margin, due to the increasingly growing market for these devices.
[0003] To reduce the cost of LED devices, copper can replace gold as the bulk metal for electrical contacts for LED dies. However gold still remains the preferred metal to provide efficient and reliable electrical and mechanical interconnections between the LED and its submount in a flip-chip configuration, wherein the upper layer of a LED die is attached to a submount, and light from the LED is emitted from a surface opposite the submount.
[0004] FIG. 1A illustrates a conventional flip-chip submount configuration of a light emitting device 100 . The submount may include a base 110 upon which contacts 120 are formed; the contacts may be plated 125 to facilitate connections 145 to the flip chip contacts 150 . The flip chip may comprise a growth substrate 170 , a light emitting element 160 , interconnect layers 165 , and contacts 150 . The growth substrate 170 , commonly sapphire or other rigid material, may be removed after the flip chip is attached to the submount.
[0005] Two contacts 120 are illustrated in FIG. 1A , separated by a channel 130 that provides electrical isolation between the two contacts 130 . In like manner, the contacts 150 are illustrated as being separated by a channel 135 . The channel 135 may be smaller than the channel 130 , in order to increase an amount of support provided to the interconnect layers 165 and light emitting element 170 by the contacts 150 . This increased support may be particularly beneficial during the removal of the growth substrate 170 . Also, the channel 130 may be larger than the channel 135 is order to accommodate potential alignment inaccuracy when the flip-chip is placed on the submount.
[0006] FIG. 1B illustrates an example thermal deformation 190 that may be caused when the light emitting device 100 is subject to high temperatures after the growth substrate 170 is removed. This deformation 190 may occur during manufacturing, and each time the light emitting device 100 is cycled from off to on. The deformation 190 may induce repeated stress to the interconnect layers 165 and the light emitting element 160 , and may cause the device 100 to fail prematurely. Additionally, the upper layer 175 of the light emitting device may be etched to increase the light extraction efficiency of the light emitting element 170 , which may cause the upper layer 175 to be more susceptible to stress induced failures.
SUMMARY OF THE INVENTION
[0007] It would be advantageous to mitigate the amount of stress in a light emitting device that is caused by thermal cycling. It would be advantageous to mitigate this stress without significantly increasing the cost of the light emitting device.
[0008] In an embodiment of this invention, elements are added to the light emitting device to reduce the stress caused by thermal cycling. Alternatively, or additionally, the materials are selected for forming contacts within a light emitting device based on their coefficient of thermal expansion and their relative cost, copper alloys providing a lower coefficient of thermal expansion than copper. Elements of the light emitting device may also be structured to distribute the stress during thermal cycling.
[0009] The light emitting device may include a submount, a light emitting structure having a metal layer with contacts separated by a channel, and one or more elements that are added to reduce a thermally induced stress in the light emitting structure in a vicinity of the channel. The added elements may include, for example, a buffer layer between the metal layer and a light emitting element in the light emitting structure, one or more gaps in the metal layer, a filler material within the channel, a filler material between contacts on the submount, and additional micro bumps in an area adjacent the channel.
[0010] The light emitting device may also, or alternatively, use an alloy with a relatively low CTE for the metal layer. A copper alloy may be used, including, for example, CuNi, CuNiTi, CuW, CuFe, and CuMo. The CTE of the alloy is preferably lower than the CTE of copper (about 16 ppm/K), more preferably less than 10 ppm/K, and more preferably less than 8 ppm/K.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The invention is explained in further detail, and by way of example, with reference to the accompanying drawings wherein:
[0012] FIGS. 1A-1B illustrates an example flip-chip on submount light emitting device.
[0013] FIG. 2 illustrates an example light emitting device with a buffer layer above the metal layer.
[0014] FIG. 3 illustrates an example light emitting device with an increased density of interconnect material adjacent the channel.
[0015] FIG. 4 illustrates an example light emitting device with gaps added to the metal layer.
[0016] Throughout the drawings, the same reference numerals indicate similar or corresponding features or functions. The drawings are included for illustrative purposes and are not intended to limit the scope of the invention.
DETAILED DESCRIPTION
[0017] In the following description, for purposes of explanation rather than limitation, specific details are set forth such as the particular architecture, interfaces, techniques, etc., in order to provide a thorough understanding of the concepts of the invention. However, it will be apparent to those skilled in the art that the present invention may be practiced in other embodiments, which depart from these specific details. In like manner, the text of this description is directed to the example embodiments as illustrated in the Figures, and is not intended to limit the claimed invention beyond the limits expressly included in the claims. For purposes of simplicity and clarity, detailed descriptions of well-known devices, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.
[0018] For ease of reference, because the stress may be shown to be most significant at the uppermost/surface layer 175 (hereinafter the epi-layer) of the light emitting element 160 , this disclosure will address the stress at the epi-layer 175 , although one of skill in the art will recognize that a stress induced failure may occur anywhere within the light emitting element 160 or the interconnects 165 . Accordingly, terms such as ‘cracking the epi-layer’ are to be interpreted as ‘cracking the epi-layer or any layer below the epi-layer’. In like manner, the layer comprising the contacts 150 may include other elements than the contacts; for ease of reference, the term ‘metal layer 150 ’ is used hereinafter to identify the layer of metal that provides support to the light emitting element 160 .
[0019] Gold has been shown to be a suitable material for forming the metal layer 150 of the light emitting device of FIGS. 1A and 1B . To reduce costs, copper has been proposed for use instead of gold for this metal layer 150 . However, a copper-to-copper interconnect may not provide the desired reliability for the light emitting device 100 ; accordingly, gold may be used as the connection material 145 , which may be in the form of a micro bump layer. In this manner, if the plating 125 of the metal layer 120 is also gold, a gold-to-gold interconnect may be formed, providing a more reliable electrical and/or thermal interconnection between the flip-chip and the submount.
[0020] Copper has a Young's modulus of 110 GPa, which is stronger than that of gold which is 77 GPa (or 26 GPa for annealed gold wires). In addition, copper has much less plastic effect than gold. Accordingly, the use of copper for the metal layer 150 reduces the probability of cracking the epi-layer 175 if/when the growth substrate 170 is removed. However, during thermal cycling, a copper metal layer will introduce significantly more deformation 190 than a gold metal layer, which may increase the likelihood of cracking the epi-layer 175 during thermal cycling.
[0021] Further, if gold micro bumps 145 are used between the copper metal layer 150 and the submount, the amount of deformation 190 caused by copper metal layer 150 is likely to be more significant, because gold is a relatively compliant material, allowing the edges of the copper metal layer 150 at the channel 135 to lift even further.
[0022] In an embodiment, the material selected for the metal layer 150 is selected based on its coefficient of thermal expansion (CTE). In particular, an alloy having a lower coefficient of thermal expansion than copper may be used to form the metal layer 150 . For example, this alloy may include CuNi, CuNiTi, CuW, CuFe, CuMo, etc. The NiTi alloy may be quite effective because it has a negative CTE.
[0023] Copper has a CTE of 16-18.5 ppm/K within a temperature range of 20-250 C. This CTE is much higher than a majority of the other materials used to form the light emitting device, and much higher than that of Alumina, which may be used as the submount, with a CTE of less than 10 ppm/K. Alloying copper with a low or even negative CTE material would provide an alloy with a CTE less than copper.
[0024] Finite Element Analysis (FEA) has demonstrated that a maximum stress caused by thermal cycling may be reduced from 1481 MPa down to 384.5 MPa when the CTE of the metal layer is reduced from 18 ppm/K to 8 ppm/K. To achieve a CTE of 8 ppm/K, a plating process may be used to form a copper alloy of Ni, TiNi, W, Fe, Mo, and so on. Particularly, Ti 0.507 Ni 0.493 alloy has a negative CTE of −21 ppm/K, and may be the most effective.
[0025] As illustrated in FIG. 2 , alternatively, or additionally, a compliant metallization layer 210 , such as gold or aluminum, may be introduced between the metal layer 150 and the interconnects 160 , to act as a buffer between the metal layer 150 and the interconnects 165 , to absorb some of the stress caused by thermal cycling.
[0026] A layer 210 of softer material, such as gold or aluminum may be applied, corresponding to the pattern used to create the metal layer 150 . This layer 250 acts as a buffer to alleviate the CTE mismatch between the metal layer 150 and the upper layers 160 and 165 . It has been estimated that a 1 um thick layer of gold may reduce the maximum principle stress within the epi-layer 150 by as much as 42%, and a 3 um thick layer of gold can reduce the maximum principle stress within the epi-layer 150 by 49%. In lieu of a continuous layer of this compliant material, a layer of micro bumps may also be used to further enhance the compliancy of this buffer layer.
[0027] Also alternatively or additionally, the compliancy of the micro bump layer 145 can be reduced. Just as introducing a buffer to absorb a portion of the deformation caused by thermal cycling, reducing the compliancy of the micro bump layer will serve to restrict this distortion. The compliancy may be reduced, for example, by reducing the height of the micro bump layer 145 , or by increasing the density or size of the micro bumps, particularly in the vicinity of the channel 135 , as illustrated at 310 of FIG. 3 .
[0028] Alternatively or additionally, the channel areas 130 or 135 may be filled with a material that has a closer CTE to the material of the metal layer 150 , thereby providing a more thermally consistent layer, reducing the distortion 190 .
[0029] The LED 100 may be overmolded with a silicone resin that molded or shaped to form a lens. Because the lens overmold material will likely flow into the channels 130 and 135 , and may have a CTE around 200 ppm/K, its thermal expansion will further increase the distortion of the metal layer 150 and the corresponding stress within the epi-layer 175 . By filling the channel 130 on the submount side with a material with a lower CTE, the thermal expansion within the channel and the effects from this expansion will be reduced. Also, by filling the channel 135 with a material having a CTE closer to the CTE of the metal layer 150 , the expansion or warping of the metal layer 150 will be reduced.
[0030] As illustrated in FIG. 4 , alternatively, or additionally, the metal layer 150 may be structured or patterned to reduce the stress caused by thermal cycling.
[0031] For example, the mask used to create the metal layer 150 may include small gaps or trenches 410 , i.e. un-metallized areas, that serve to redistribute the effects of the CTE mismatch between the metal layer 150 and the upper layers 160 and 165 . These gaps 410 split the lateral stresses and strains that are incurred in the upper layers 160 and 165 due to the thermal expansion of the layer 150 , thereby mitigating the stress at the region above the channel 135 as well.
[0032] While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive; the invention is not limited to the disclosed embodiments.
[0033] Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage. A computer program may be stored/distributed on a suitable medium, such as an optical storage medium or a solid-state medium supplied together with or as part of other hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems. Any reference signs in the claims should not be construed as limiting the scope. | Elements are added to a light emitting device to reduce the stress within the light emitting device caused by thermal cycling. Alternatively, or additionally, materials are selected for forming contacts within a light emitting device based on their coefficient of thermal expansion and their relative cost, copper alloys being less expensive than gold, and providing a lower coefficient of thermal expansion than copper. Elements of the light emitting device may also be structured to distribute the stress during thermal cycling. | 7 |
FIELD OF THE INVENTION
The present invention relates to a water treating apparatus attached to the faucet of the water pipe to improve water quality.
DESCRIPTION OF THE PRIOR ART
The taste or bioactivity of water seems to be much effected by the sizes of clusters of water. The smaller sizes of clusters of water seem to result in better taste and bigger bioactivity of water because water having smaller-sized clusters is easily absorbed in plants or animals.
Hitherto, it is difficult to artificially produce water having small-sized clusters and one must get water having small-sized clusters from natural water.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to artificially produce water having small-sized clusters. Said object can be attained by a water treating apparatus consisting of a cylindrical body having a water inlet at the upper end and a water outlet at the lower end wherein a water passage is longitudinally formed in said cylindrical body, and a blade member is arranged in said cylindrical body and gives water passing through in said water passage revolution force and shear force.
To improve quality of city water containing chlorinated material, it is preferable to arrange a ceramic filling layer in said water passage and preferably said ceramic filling layer consists of a large number of ceramic balls treated with a ferric-ferrous iron to remove said chlorinated material.
Further to make foams in treated water, a partition is formed under the blade member and a nozzle is attached from the center of the underside of said partition and a water strewing dome body is installed opposite to the end of said nozzle. It is preferable to treat said water strewing dome body with a ferric-ferrous iron to increase the improving effect of said water strewing dome body for water.
Further it is preferable to arrange movably a plural number of balls treated with a ferric-ferrous iron under said blade member to increase further the improving effect of water.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 to FIG. 9 relate to our embodiment of the present invention.
FIG. 1 is a perspective view of the overhauled water treating apparatus.
FIG. 2 is a cross sectional view of the water treating apparatus.
FIG. 3 is a perspective view of the inside of the under side cylinder.
FIG. 4 is a perspective view of the blade member.
FIG. 5 is a plane view of the blade member.
FIG. 6 is a cross sectional view along a line A—A in FIG. 1 .
FIG. 7 is an enlarged cross sectional view of the nozzle.
FIG. 8 is a perspective view of the water strewing dome body.
FIG. 9 is a perspective view to illustrate the flow of water in the underside of the check valve.
FIG. 10 and FIG. 11 relate to another embodiment of the present invention.
FIG. 10 is a cross sectional view corresponding to FIG. 6 .
FIG. 11 is a view to illustrate the flow of water in the underside of the check valve.
FIG. 12 is a cross sectional view of the foaming cylinder of another embodiment.
DETAILED DESCRIPTION
FIG. 1 to FIG. 9 show an embodiment of the present invention. A water treating apparatus ( 1 ) shown in FIGURES has a cylindrical body ( 2 ) in which a water passage ( 3 ) is longitudinally formed and a partition ( 6 ) having a center hole ( 5 ) to pass water is arranged in the middle of said water passage ( 3 ) of said cylindrical body ( 2 ) as shown in FIG. 2 and the diameter of the upper and lower end parts of said cylindrical body ( 2 ) are respectively reduced to form stair faces ( 7 )( 8 ) and the circumferential surface of said upper and lower end parts are respectively threaded to form screw parts ( 9 )( 10 ). An upper socket ( 11 ) and a lower socket ( 17 ) are respectively screwed on said screw parts ( 9 ) ( 10 ).
The diameter of the upper side of said upper socket ( 11 ) is reduced to form a stair face ( 12 ) and the circumferential surface of said upper side of said upper socket ( 11 ) is threaded to form a screw part ( 13 ) and a pressing tube ( 14 ) is equipped in the lower side of said upper socket ( 11 ) as shown in FIG. 2. A packing plug ( 15 ) made of a rubber of an elastomer is inserted into the upper end of said upper socket ( 11 ) and a cap ( 16 ) having a water hole ( 16 A) at the upper end is screwed on the screw part ( 13 ) of said upper socket ( 11 ) and said packing plug ( 15 ) is pressed and fixed by said cap ( 16 ).
A partition ( 18 ) is arranged in the upper side of said lower socket ( 17 ) as shown in FIG. 2 and FIG. 3, and in said lower socket ( 17 ), a cylindrical flange ( 19 ) is formed on said partition ( 18 ) and a nozzle ( 20 ) is formed from the under side of said partition ( 18 ).
As shown in FIG. 2, O-ring ( 21 ) intermediates between said cylindrical body ( 2 ) and said upper socket ( 11 ) and a retainer ring ( 23 ) intermediates between said cap ( 16 ) and said packing plug ( 15 ) to give said water treating apparatus ( 1 ) an air-tight structure.
A ceramic filling layer ( 25 ) consisting of a large number of ceramic balls ( 24 ) is arranged on said partition ( 6 ) in said cylindrical body ( 2 ) of said water treating apparatus ( 1 ) as shown in FIG. 2 and the upper end of said ceramic filling layer ( 25 ) is pressed by said pressing tube ( 14 ) and further said ceramic filling layer ( 25 ) is supported by a cross frame ( 26 ) put on said partition ( 6 ).
A check valve ( 27 ) is arranged under said partition ( 6 ) as shown in FIG. 2 . Said check valve ( 27 ) consists of a valve supporting case ( 28 ), a valve rod ( 31 ) which slides up and down inserted in a sliding hole ( 30 ) formed at the upper end of a center tube ( 29 ) of said valve supporting case ( 28 ), a valve ( 32 ) equipped at the upper end of said valve rod ( 31 ), an O-ring ( 33 ) attached around said valve ( 32 ), and a coil spring ( 34 ) pressing said valve rod ( 31 ) toward upper side. As shown in FIG. 4, a plural number of spokes ( 35 ) are radiately arranged between said center tube ( 29 ) and said valve supporting case ( 28 ) and a blade ( 36 ) slanting toward down side is stretched from the left side of each spoke ( 35 ), a blade member ( 36 A) is constructed by said spokes ( 35 ) and said blades ( 36 ) are in said valve supporting case ( 28 ) and in said blade member ( 36 A), spaces ( 37 ) are formed between blades ( 36 ) neighboring to each other as shown in FIG. 4 and FIG. 5 .
A plural number of longitudinal slits ( 38 ) are formed on the circumferential wall of the lower end part of said center tube ( 29 ) of said valve supporting case ( 28 ) of said check valve ( 27 ) and said center tube ( 29 ) of said valve supporting case ( 28 ) of said check valve ( 27 ) is supported on said partition ( 18 ) of said lower socket ( 17 ). As shown in FIG. 6, each longitudinal slit ( 38 ) is centripetally arranged along the normal PL of the circumferential surface of said center tube ( 29 ). Further, said valve ( 32 ) of said check valve ( 27 ) shuts said center hole ( 5 ) of said partition ( 6 ) of said cylindrical body ( 2 ) pressed by said coil spring ( 34 ).
A cylindrical foaming chamber ( 39 ) is inserted in the lower side of said lower socket ( 17 ) and a space Si is formed between the inside of said lower socket ( 17 ) and the outside of said cylindrical foaming chamber ( 39 ) as shown in FIG. 2 and an inner cylinder ( 40 ) is inserted in the upper side of said cylindrical foaming chamber ( 39 ). The width of said space S 1 is preferably more than 1.0 mm and the larger width of said space S 1 is better. Said nozzle ( 20 ) of said partition ( 18 ) is inserted in said inner cylinder ( 40 ) from the upper side through an inserting hole ( 43 ) at the upper end of said inner cylinder ( 40 ). Said inserting hole ( 43 ) of said inner cylinder ( 40 ) has a taper shape reducing its diameter toward the under side and as shown in FIG. 7, the width W between the outside of said nozzle ( 20 ) and inside of the lower end of said inserting hole ( 43 ) is preferably set to be in the range between 0.5 to 2.0 mm.
A water strewing dome body ( 42 ) supported by a bed frame ( 41 ) is installed in the center of the lower part of said inner cylinder ( 40 ) as shown in FIG. 8 . Said water strewing dome body ( 42 ) consists of a mineral ball and is arranged under said nozzle ( 20 ) opposing to the end of said nozzle ( 20 ) and surrounded by a ring body ( 45 ). A plural number of rib spacer ( 44 ) are formed on the upper face of said inner cylinder ( 40 ) of said cylindrical foaming chamber ( 39 ) and as shown in FIG. 2, a space S 2 is formed between the upper face of said cylindrical foaming chamber ( 39 ) and the under side of said partition ( 18 ) of said lower socket ( 17 ).
A plural number of balls ( 46 ) made of stainless steel, ceramics, and the like are preferably arranged under said check valve ( 27 ). As shown in FIG. 9, said balls ( 46 ) are supported on a supporting plate ( 48 ) having a center hole ( 47 ) as a water passage and said supporting plate ( 48 ) is put on the upper end of said cylindrical flange ( 19 ) of said lower socket ( 17 ).
Said ceramic ball ( 24 ) is made of, for example, silicon oxide, aluminum oxide, zirconium oxide, titanium oxide, silicon nitride, boron nitride, silicon carbide, and the like and a mixture of two or more kinds of said ceramics also may be used as the material of said ceramic ball ( 24 ). A preferable mixture of said ceramics is, for example, a mixture of silicon oxide and aluminum oxide and said ceramic ball ( 24 ) is preferably treated by a ferric-ferrous iron. To treat said ceramic ball with said ferric-ferrous iron, said ceramic ball is dipped in a solution of said ferric-ferrous iron or said ceramic ball is contacted with air which passed through said solution of said ferric-ferrous iron.
The above-said ferric-ferrous iron solution is prepared as follows:
1 g of ferric chloride is added to 5 ml of 12N caustic soda aqueous solution and stirred. The dissolved solution is kept for 5 or more hours at room temperature. Said solution is neutralized at about pH7 by 12N aqueous HCl. The neutralized solution is filtered by filter paper (No. 5C) and concentrated in vacuum to obtain crystal. Crystal is vacuum-dried in a desiccator. The resulting dried material is added to 10 ml of mixed solvent of isopropanol and water (80:20 weight ratio). The resulting solution is filtered by filter paper (No. 5C) and vacuum-concentrated. After removing the solvent, crystal is dried. The above-said process of extraction, concentration and drying is continued several times to obtain fine crystal of activated iron chloride. 2 ppm solution is prepared by diluting said crystal with distilled water.
1 g of ferrous sulfate is added to 5 ml of 12N HCl aqueous solution and stirred. The dissolved solution is filtered by filter paper (No. 5C) and then vacuum-concentrated to obtain crystal. Crystal is vacuum-dried in a desiccator. The resulting solution is filtered by filter paper (No. 5C) and vacuum-concentrated. After removing the solvent, crystal is dried. The above-said process of extraction, concentration and drying is continued several times to obtain fine crystal of activated iron chloride. 2 ppm solution is prepared by diluting said crystal with distilled water.
Further, said balls ( 46 ) arranged under said check valve ( 27 ) are preferably treated with said ferric-ferrous iron in the same way as said ceramic ball ( 24 ). Still further, said mineral material used as the material of said water strewing dome body ( 42 ) is, for example, crystal, quartz, feldspar, jade and the like, and said mineral material is preferably treated with said ferric-ferrous iron in the same way as said ceramic ball ( 24 ).
Further, a plural number of nets ( 50 ) piled together are arranged at the lower end of said cylindrical foaming chamber ( 39 ). Said water treating apparatus ( 1 ) is attached to, for example, the faucet ( 49 ) of the water pipe as shown in FIG. 2 and the city water is introduced into said water treating apparatus ( 1 ) through said faucet ( 49 ). First, chlorinated material in said city water is removed by letting it pass through said ceramics filling layer ( 25 ) and the valve ( 32 ) of said check valve ( 27 ) is pushed down by the pressure of said water and said water is introduced into said valve supporting case ( 28 ) and then said water is revolved by blades ( 36 ) of said blade member ( 36 A) in said valve supporting case ( 28 ) as shown by arrows in FIG. 5 and FIG. 9 and further, effected by shear force to chop clusters of said water into finer clusters. If said water flows upstream by colliding to said blades ( 36 ) of said blade member ( 36 A) in said valve supporting case ( 28 ), said valve ( 32 ) of said check valve ( 27 ) may shut said center hole ( 5 ) of said partition ( 6 ) pushed by said coil spring ( 34 ) to prevent said water from flowing upstream into said ceramic filling layer ( 25 ).
As above described, said water is revolved and chopped to form finer clusters and passes through spaces ( 37 ) between blades ( 36 ) to flow into the upper side of said lower socket ( 17 ) and said revolving water contacts with balls ( 46 ) supported on said supporting plate ( 48 ) shown by the arrow in FIG. 9 . By said revolving water, said balls ( 46 ) move as shown by arrows in FIG. 9 and said water further closely contacts with said balls ( 46 ) to remove further chlorinated materials and the clusters are further chopped to be very finer clusters, thus said water treated above described flows to the under side of said supporting plate ( 48 ) through the space between the outside of said center tube ( 29 ) and the inside of said center hole ( 47 ) of said supporting plate ( 48 ) and said water is introduced to said nozzle ( 20 ) of said lower socket ( 17 ) through said longitudinal slits ( 38 ) of said center tube ( 29 ) as shown in FIG. 6 being spouted toward said water strewing dome body ( 42 ) from said nozzle ( 20 ).
When said water is spouted from said nozzle ( 20 ), air is sucked into said cylindrical foaming chamber ( 39 ) through the space Si between the outside of said cylindrical foaming chamber ( 39 ) and the inside of said lower socket ( 17 ) and the space S 2 between the upper side of said cylindrical foaming chamber ( 39 ) and the under side of said partition ( 18 ) of said lower socket ( 17 ) and further the space between the outside of said nozzle ( 20 ) and the inside of said inserting hole ( 43 ) of said inner cylinder ( 40 ) of said cylindrical foaming chamber ( 39 ). As above described, when the space S 1 between the outside of said cylindrical foaming chamber ( 39 ) and the inside of said lower socket ( 17 ) is set to be larger than 1.0 mm, air may smoothly pass through said space S 1 . Further, when said inserting hole ( 43 ) of said inner cylinder ( 40 ) has a taper shape reducing its diameter toward the under side and the space between the outside of said nozzle ( 20 ) and the inside of the lower end of said inserting hole ( 43 ) is set to be in the range between 0.5 to 2.0 mm, the sucking speed of air is effectively accelerated.
Said water spouted from said nozzle ( 20 ) collides to said water strewing dome body ( 42 ) to be radially sprinkled and foams are formed by mixing air sucked into said cylindrical foaming chamber ( 39 ) to remove the chlorinated material and the like and further said water is filtered by said plural number of nets ( 50 ) of said cylindrical foaming chamber ( 39 ). After the filtration by said plural number of nets ( 50 ), said water is spouted from the water outlet ( 51 ) and foams in said water are crushed by the spouting pressure to generate anion. The number of said generated anion is in the range of 12000 to 14000/cm 3 by Lenard effect.
Water before treatment by said water treating apparatus is titrated by the chlorine detecting agent and as a result, chlorine is detected in said water while no chlorine is detected by the same titration test. Further, the sizes of the clusters of water before and after treatment are respectively detected by 17 O-NMR spectral analysis and the results are that O-NMR spectral line width as an indicator of the size of the cluster before treatment is 93.4 Hz, while O-NMR spectral line width after treatment is 65.1 Hz.
FIG. 10 and FIG. 11 show another embodiment of the present invention. In this embodiment, slits ( 38 A) of a center tube ( 29 A) of said check valve ( 27 ) is arranged slanting from the normal PL of the circumferential surface of said center cylindrical body ( 29 A) as shown in FIG. 10 to give said water revolving force shown by an arrow in FIG. 11 when said water is introduced to said nozzle ( 20 ) and then said water is spouted toward said water strewing dome body ( 42 ) with revolving. Accordingly, the clusters of said water are further finely chopped and the 17 O-NMR spectral line width of the clusters after treatment is 60.4 Hz in this embodiment.
Further in the present invention, a plural number of (three sheets of) nets ( 50 A, 50 B, 50 C) piled together may be arranged in the water outlet ( 51 ) of the cylindrical foaming chamber ( 39 ). A size of mesh of said nets ( 50 A, 50 B, 50 C) is generally set to be in the range between 0.25 to 1.0 mm 2 . By passing water through said nets, the clusters of water are further chopped into finer clusters. In this case, 17 O-NMR spectral line width after passing through said nets is 59.8 Hz.
The scope of the present invention is not limited to the above described embodiments. For instance, ceramic chips may be used instead of ceramic balls in said ceramic filling layer. Further, said check valve and said blade member may be separated from each other. Still further, said water strewing dome body may have a pyramid shape, a cone shape, and the like.
In the present invention, water has very fine clusters and contains substantially no chlorinated materials and as a result, water having a preferable taste and bioactivity is easily obtained. | The object of the present invention is to easily produce water having fine clusters and containing little chlorinated material. Said object is attained by a water treating apparatus consisting of a cylindrical body having a water inlet at the upper end and a water outlet at the lower end wherein a water passage is longitudinally formed in said cylindrical body, and a blade member is arranged in said cylindrical body and gives water passing through said water passage revolution force and shear force. | 2 |
FIELD
The present description relates to a method for controlling a lift pump operating as part of a direct injection fuel system.
BACKGROUND
It is common for direct fuel injected engines to have two fuel pumps. One example of a two pump direct injection fuel system is described in U.S. Pat. No. 6,230,688. This patent describes a fuel system wherein one fuel pump (i.e., the lift pump) lifts fuel from a fuel tank and delivers the fuel to a second fuel pump (i.e., the injection pump) at a first pressure. The second fuel pump increases the fuel pressure to a second pressure so that fuel can be directly injected into a cylinder. Current or voltage supplied to the lift pump is controlled in response to a pump speed sensor or in response to a pressure sensor.
The above-mentioned method can also have several disadvantages. In particular, the method requires a sensor to monitor the lift pump outlet pressure or the lift pump speed. This arrangement adds cost to the system and is therefore less desirable than a system that does not require sensors. In addition, the sensors may reduce system reliability as the system may not function as well if a sensor degrades.
The inventors herein have recognized the above-mentioned disadvantages and have developed a method that offers substantial improvements.
SUMMARY
One embodiment of the present description includes a method to operate a lower pressure pump operating as part of a direct injection fuel system, the method comprising: operating a lower pressure pump in a first mode during a first operating condition of an internal combustion engine, said lower pressure pump supplying fuel to a higher pressure pump that supplies fuel to fuel injectors that directly inject fuel to a cylinder, said first operating mode comprising adjusting energy supplied to said lower pressure pump as output from a sensor located downstream of said higher pressure pump varies while said higher pressure pump is substantially deactivated; and operating said lower pressure pump in a second mode during a second operating condition of said internal combustion engine, said second operating mode comprising varying energy supplied to said lower pressure pump as operating conditions of said internal combustion engine vary while said higher pressure pump is activated. This method overcomes at least some disadvantages of the above-mentioned method.
The expense and complexity of lift pump (i.e., lower pressure pump) control in a direct injection fuel system can be reduced while the capacity to regulate lift pump output is maintained. For example, lift pump outlet pressure can be controlled by using a pressure sensor that is located downstream of an injection pump (i.e., higher pressure pump), wherein the injection pump is located downstream from the lift pump. Specifically, when the injection pump is commanded off, pressure develops at the lift pump and advances down the fuel supply line and propagates through the injection pump. As a result, the fuel line and fuel rail located downstream from the injection pump are pressurized by the lift pump. A pressure sensor in the fuel rail can then be used to feedback fuel line pressure so that the lift pump can be controlled. In this way, the lift pump output pressure can be controlled without having to place an extra pressure sensor between the lift pump and the injection pump. Furthermore, the amount of energy supplied to the lift pump to achieve a particular fuel line pressure can be monitored and stored into memory for subsequent use.
In fuel delivery modes where the injection pump is activated, the current commands used to achieve a particular lift pump outlet pressure while the injection pump was off can be retrieved from memory and output so that the particular pressure is achieved. This allows the lift pump pressure to be controlled without a pressure transducer located at the lift pump outlet. In this mode, the injection pump can be controlled by the pressure sensor located downstream of the injector pump. Thus, a single pressure sensor located downstream of an injection pump can be used to control the outlet pressures of a lift pump and an injection pump.
The present description can provide several advantages. In particular, the approach controls fuel pressure from two fuel pumps connected in series using a single pressure transducer. Further, since only a single pressure transducer is used, system reliability can be improved because there is less probability that a sensor will degrade in the system.
The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The advantages described herein will be more fully understood by reading an example of an embodiment, referred to herein as the Detailed Description, when taken alone or with reference to the drawings, wherein:
FIG. 1 is a schematic diagram of an engine, its fuel system, and its control system;
FIG. 2 is a flowchart of an example open-loop lift pump control method;
FIG. 3 is a flowchart of an example lift pump mode control method;
FIG. 4 is a schematic diagram of an example fuel pump operating mode map; and
FIG. 5 is a plot of an example fuel pump performance map.
DETAILED DESCRIPTION
Referring to FIG. 1 , internal combustion engine 10 , comprising a plurality of cylinders, one cylinder of which is shown in FIG. 1 , is controlled by electronic engine controller 12 . Engine 10 includes combustion chamber 30 and cylinder walls 32 with piston 36 positioned therein and connected to crankshaft 31 . Combustion chamber 30 is known communicating with intake manifold 44 and exhaust manifold 48 via respective intake valve 52 an exhaust valve 54 . Each intake and exhaust valve is operated by a mechanically drive cam. Alternatively, intake valves and/or exhaust valves may be operated by electrically actuated valves.
Intake manifold 44 is shown communicating with optional electronic throttle 62 . Fuel is injected directly into cylinder 30 by way of fuel injector 66 . The amount of fuel delivered is proportional to the pulse width of signal FPW sent from controller 12 . Fuel is delivered to fuel injector 66 by injection pump 74 . Check valve 75 allows fuel flow from injection pump 74 to fuel injector 66 and limits flow from fuel injector 66 to injection pump 74 . Lift pump 72 provides fuel from fuel tank 71 to injection pump 74 . Check valve 73 allows fuel to flow from fuel pump 72 and limits fuel flow backwards into fuel pump 72 . Pressure regulator 76 maintains a substantially constant (i.e., ±0.5 bar) fuel supply pressure to injection pump 74 when bypass flow is present. Alternatively, pressure regulator 76 may be eliminated from the system, if desired.
Note that the lift pump and/or injection pumps described above may be electrically, hydraulically, or mechanically driven without departing from the scope or breadth of the present description.
Distributor-less ignition system 88 provides ignition spark to combustion chamber 30 via spark plug 92 in response to controller 12 . Universal Exhaust Gas Oxygen (UEGO) sensor 45 is shown coupled to exhaust manifold 48 upstream of catalytic converter 47 . Converter 47 can include multiple catalyst bricks, in one example. In another example, multiple emission control devices, each with multiple bricks, can be used. Converter 47 can be a three-way type catalyst in one example.
Controller 12 is shown in FIG. 1 as a conventional microcomputer including: microprocessor unit 102 , input/output ports 104 , and read-only-memory 106 , random-access-memory 108 , 110 Keep-alive-memory, and a conventional data bus. Controller 12 is shown receiving various signals from sensors coupled to engine 10 , in addition to those signals previously discussed, including: engine coolant temperature (ECT) from temperature sensor 112 coupled to water jacket 114 ; a position sensor 119 coupled to a accelerator pedal; a measurement of engine manifold pressure (MAP) from pressure sensor 122 coupled to intake manifold 44 ; a fuel rail pressure sensor 77 ; a throttle position sensor 69 ; a measurement (ACT) of engine air amount temperature or manifold temperature from temperature sensor 117 ; a engine position sensor from a Hall effect sensor 118 sensing crankshaft 31 position; and power driver circuitry capable of providing actuating energy to actuate valves as well as capability to provide current for heating valve actuators. In one aspect of the present description, engine position sensor 118 produces a predetermined number of equally spaced pulses every revolution of the crankshaft from which engine speed (RPM) can be determined.
Controller 12 storage medium read-only memory 106 can be programmed with computer readable data representing instructions executable by processor 102 for performing the methods described below as well as other variants that are anticipated but not specifically listed.
Referring now to FIG. 2 , a flow chart of an example open-loop lift pump control method is shown. The method of FIG. 2 allows a lift pump that feeds an injection pump to be operated without a pressure regulator located between the lift pump and the injection pump. The absence of a pressure regulator can save system cost and can allow the lift pump to be operated during an engine start at higher pressures. Typically, pressure regulators are set to regulate at a pressure that is lower than the maximum pump pressure. When the pressure regulator is removed from the system, the lift pump can be operated at a higher pressure so that fuel injectors may be charged with higher pressure fuel while the engine is not rotating and while the injection pump is inactive. This can improve engine starting and lower engine emissions.
In step 201 , operating conditions are determined. In one embodiment, controller 12 determines engine fuel flow rate, ambient air temperature, and lift pump temperature. In one embodiment, engine fuel flow rate can be determined from sensing fuel rail pressure and injection timing. Then, these parameters can be used to look up fuel flow using injector characterizations. In an alternative embodiment, fuel flow can be determined from the engine air flow and the desired air-fuel ratio. Lift pump temperature can be inferred from lift motor winding resistance based on applied voltage and measured current. The lift pump temperature estimate may also be based on ambient temperature since it is close to tank temperature and the lift pump is immersed in the tank. The routine proceeds to step 203 after operating conditions are determined.
In step 203 , the desired lift pump output pressure is determined. Lift pump performance can be empirically determined and mapped as shown in FIG. 5 . A desired lift pump pressure can be achieved by operating the lift pump at different voltages, knowing the injector fuel flow rate. However, lift pump power consumption can be reduced by selecting a lower output pressure at which the injection pump can still achieve the target fuel rail pressure.
In one embodiment, lift pump performance is stored in table or function format in memory. The desired lift pump pressure can be retrieved from memory based on operating conditions. Once the lift pump output pressure is determined the routine proceeds to step 205 .
In step 205 , the desired lift pump energy is determined. Energy may be regulated to the lift pump in an electrical form (e.g., voltage, current, duty cycle) or in an alternate form such as speed, displacement, mechanical energy, or hydraulic energy. In one example, voltage can be applied at a frequency and duty cycle so that the lift pump is supplied an average voltage.
A voltage (that will operate the lift pump at a pressure determined in step 203 , given the flow rate computed in step 201 ) is selected from an empirically determined pump flow map that is similar to the one illustrated in FIG. 5 . The operating voltage is selected from the lower half of the range of voltages that will operate the lift pump at the desired lift pump pressure. In one example, the lowest voltage that will operate the pump at the desired lift pump pressure is selected to reduce pump energy consumption. The routine proceeds to step 207 .
In step 207 , the lift pump energy is output to the lift pump. In one embodiment, battery voltage is controlled by output from engine control module 12 . The control module closes a switch that delivers battery voltage to the lift pump at a predetermined frequency. The duty cycle can then be modified to change the average voltage supplied to the lift pump. The routine exits after adjusting the lift pump energy.
Referring now to FIG. 3 , a flow chart of an example lift pump control method is shown. The method of FIG. 3 may be applied whether or not a pressure regulator is installed between a lift pump and an injection pump. If a pressure regulator is omitted, the method of FIG. 2 can be used to operate the lift pump in open-loop mode.
In step 301 , the routine determines operating conditions. Operating conditions may include but are not limited to the following: engine load (i.e., the amount of air inducted by the engine relative to the theoretical amount of air the engine is capable of inducting), engine speed, engine temperature, injection timing, spark timing, driver torque demand, ambient air temperature, crankshaft position, camshaft position (valve timing), and throttle position. After engine operating conditions are determined the routine proceeds to step 303 .
In step 303 the routine determines the desired fuel rail pressure. Operating conditions determined in step 301 are used to determine desired fuel rail pressure. In one embodiment, engine speed and load are used to index tables that have empirically determined values that describe a desired fuel rail pressure. These values may be further modified based on one or more of the following: injection timing, ambient air temperature, engine temperature, and valve timing. After the desired fuel rail pressure is determined, the routine proceeds to step 305 .
In step 305 , the fuel pump operating mode is selected. Typically, injection pumps are mechanically driven pumps that can produce noise and vibration as they pump fuel. This type of pump is often fitted with a valve that modulates (i.e., a fuel modulation valve) the fuel volume transferred into the fuel rail. The control is capable of substantially deactivating the pump. In some instances, pump noise can be masked by the noise from the internal combustion engine and/or road noise. For example, when a vehicle is being driven and when engine speed is greater than engine speed during idle conditions, pump noise can become indistinguishable from other engine and vehicle noise. As a result, injection pump noise is of little consequence during these conditions. On the other hand, when engine speed is near idle speed, injection pump noise can exceed engine noise such that fuel pump noise becomes audible and noticeable to a driver. Under these conditions, it can be desirable to deactivate the injection pump and supply fuel solely from the lift pump. When the injection pump is deactivated, fuel pressure created by the lift pump forces fuel through the injection pump and pressurizes the fuel rail located downstream of the injection pump. Pressure in the fuel rail approaches the pressure developed at the lift pump, minus pressure losses associated with pumping fuel through the injection pump and fuel lines. Based on the above conditions, and other conditions, it can be shown that it is desirable to have more than one pump mode for a two pump direct fuel injection system.
In one embodiment, fuel pump mode can be determined from the desired fuel rail pressure determined in step 303 and a desired fuel flow rate. In this embodiment, only the lift pump is operated if the lift pump pressure is sufficient to attain the required injection fuel flow rates. Both the lift pump and the injection pump are operated when an increased rail pressure needed to attain the desired fuel flow rates through the injectors. In another embodiment, fuel pump mode may be selected as a function of one or more parameters including but not limited to engine speed, engine load, ambient air temperature, and time since engine start. Mode selection may be facilitated by a state machine, logic, or other known methods. In this way, it is possible to produce different pump modes (i.e., lift pump active and injection pump deactivated or lift pump active and injection pump active) for different operating conditions. The routine proceeds to step 307 after the pump control mode is selected.
In step 307 , the routine determines which control commands should be executed based on the selected pump mode. If a two pump mode has been selected, the routine proceeds to step 309 . Otherwise, the routine proceeds to step 310 .
In step 309 , the injection pump is activated. An electric signal is sent from engine controller 12 to a pump modulation valve located in the injection pump. The modulation valve allows the injection pump to perform work on the fuel, thereby increasing pressure in the fuel rail.
In one embodiment, the increase in fuel rail pressure caused by reactivating the injection pump is anticipated or predicted by counting the number of fuel pump strokes after the injection pump is reactivated and the position of the modulation valve. In particular, the pressure observed in the fuel rail by the fuel rail pressure sensor is adjusted based on the pumped volume, the initial fuel rail pressure, and the fuel rail volume. The engine controller can then adjust the fuel injector timing based on the adjusted fuel pressure. This allows the engine controller to compensate fuel injector timing based on the fuel pressure increase that occurs when the injection pump is reactivated. After the pump is operated for a predetermined number of pump cycles, observed fuel rail pressure can be used to determine fuel injector timing without the need to adjust the observed fuel rail pressure.
The routine proceeds to step 311 after activating the injection pump.
In step 311 , energy (e.g., current/voltage or torque) is delivered to the lift pump based on data stored in step 314 . The energy can be varied as the operating conditions of the engine vary. For example, the energy supplied to the lift pump can be varied as engine speed and/or engine load vary. Alternatively, lift pump energy can be varied as the fuel delivery rate to the engine is varied. Also note that the energy may be adjusted to compensate for fuel or pump properties, which may be a function of fuel temperature. Fuel temperature may be measured or inferred. For example, when operating at lower temperatures pump current may be increased to compensate for increase lift pump friction, changes in fuel viscosity, and/or fuel vapor pressure. After the lift pump energy command is output the routine proceeds to step 313 .
In step 313 , the fuel rail pressure is determined. Fuel rail pressure is monitored downstream of the injection pump by pressure sensor 77 . The sensor output voltage is converted into a pressure reference in controller 12 . The observed fuel rail pressure can vary with engine speed and fuel flow rate. Engine control module 12 can adjust a signal to a modulating valve in the injection pump based on the pressure observed by sensor 77 to adjust the fuel rail pressure. In this way, pressure in the fuel rail can be closed-loop controlled. After determining fuel rail pressure, the routine proceeds to step 315 .
In step 315 , fuel injector timing is set and output. Fuel pressure determined in step 313 , along with other parameters such as engine speed, engine load, and desired air-fuel ratio are used to determine fuel injection timing. Unique injection timings are output for each fuel injector so that the torque and air-fuel ratio of each cylinder can be individually controlled. The routine exits after outputting the determined fuel injection timings.
In step 310 , the injection pump is substantially deactivated. That is, the injection pump efficiency is reduced such that the pump efficiency is below 10%. Single pump mode is typically active at lower engine speeds and loads. For example, the lift pump may remain active while the injection pump is deactivated during idle or during deceleration fuel cut-out conditions. This may lower powertrain noise and may also increase engine efficiency since high injection pressures may not be necessary under these conditions. After the pump is deactivated, the routine proceeds to step 312 .
In step 312 , fuel rail pressure is determined. Similar to step 313 , fuel rail pressure is determined by converting the pressure sensor output voltage into units of pressure in the engine controller. The routine then proceeds to step 314 .
In step 314 , the lift pump energy is adjusted so that the pressure observed by pressure sensor 77 approaches a desired fuel rail pressure. The fuel sensor provides pressure feedback to the engine controller which in turn adjusts lift pump energy until a desired fuel rail pressure is achieved. The desired fuel rail pressure may be empirically determined or it may be determined based on injector flow characteristics. In one embodiment, the lift pump current/voltage may be feedback controlled using a proportional/integral (PI) controller, or another controller variant if desired. When the observed rail pressure (determined in step 312 ) substantially (e.g., ±1 bar) reaches the desired fuel rail pressure, the energy (e.g., current/voltage) command issued to the lift pump is stored into controller memory as the engine operates to correspond to the desired fuel rail pressure. In addition, the controller may also determine and store into memory, while the engine is operating or off, an intermediate fuel pressure (i.e., a fuel pressure between the lift pump outlet and the injection pump) by subtracting empirically determined data representing injection pump pressure losses and fuel line pressure losses from the measured rail pressure, if desired.
Stored fuel rail pressure measurement, intermediate fuel rail pressure inference, and supplied lift pump energy are used in open-loop pump control step 311 . If desired, additional factors that may affect the fuel rail pressure that is developed by the lift pump may also be stored. These factors can be used to modify the energy command that is used to achieve a desired fuel rail pressure or lift pump pressure. In one embodiment, warmed-up engine operating conditions and an ambient temperature of 23° C. are considered nominal lift pump operating conditions over the single lift pump mode operating range. In this embodiment, current/voltage supplied to the lift pump as well as fuel rail pressure are stored under these operating conditions. The stored current/voltage can also be modified by factors that are a function of operating conditions (e.g., engine temperature and ambient air temperature) to determine open-loop lift pump parameters as operating conditions vary from nominal conditions.
After the supplied lift pump energy is adjusted and parameters are stored to memory, the routine proceeds to step 316 .
In step 316 , fuel injector timing is set and output. Fuel pressure determined in step 312 , along with other parameters such as engine speed, engine load, and desired air-fuel ratio are used to determine fuel injection timing. Unique injection timings are output for each fuel injector so that the torque and air-fuel ratio of each cylinder can be individually controlled. The routine exits after outputting the determined fuel injection timings.
Referring now to FIG. 4 , an example fuel pump control mode map is shown. The x-axis represents engine speed increasing from left to right. The y-axis represents increasing engine load from bottom to top. Region 401 (i.e., the area bounded by vertical line 407 and horizontal line 405 ) represents engine operating conditions when fuel is pumped to the engine by only the lift pump. That is, the injection pump is deactivated in this mode. As mentioned above, this mode can be useful when it is desirable to reduce the amount of noise generated by pumping fuel to the engine. Region 403 (i.e., the area above line 405 and to the right of line 407 ) represents engine operating conditions when fuel is pumped to the engine by two fuel pumps. Specifically, when a lift pump transfers fuel to the injection pump, and when the injection pump increases fuel pressure above the lift pump pressure. It should be noted that the boundaries represented by lines 405 and 407 may vary between different applications and are only exemplary in this figure. It should also be noted that there may be regions within region 401 where two pumps are used to supply fuel to the engine. In another embodiment, there may be more than one distinct single pump operating region. That is, there may be two or more regions where the lift pump supplies fuel to the engine while the injector pump is deactivated.
Referring now to FIG. 5 , a plot of an example fuel pump operating map is shown. The x-axis represents fuel flow rate increasing from left to right. The y-axis represents fuel pressure at the pump outlet increasing from bottom to top. Each line (e.g., lines 501 and 503 ) represent the pump operating characteristics at a fixed voltage. Line represents pump output when the pump is supplied with 5 volts. Line 503 represents pump output when the pump is supplied with 13.5 volts. The lines in between lines 501 and 503 represent pump characteristics at when the pump is supplied different intermediate voltages. Notice that one fixed supply voltage is capable of supplying a range of pump outlet pressures and flow rates.
This concludes the description. The reading of it by those skilled in the art would bring to mind many alterations and modifications without departing from the spirit and the scope of the description. For example, I3, I4, I5, V6, V8, V10, and V12 engines operating in natural gas, gasoline, diesel, or alternative fuel configurations could use the present description to advantage. | An economical method for controlling a lift pump operating as part of a direct injection fuel system is described. According to the method, at least two distinct operating modes are provided. | 5 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to apparatus and systems for restricting access to containers and vehicles, and more particularly, to devices for preventing unauthorized entry into unattended trailers.
[0002] Trailers serve a wide variety of personal and business needs, ranging from camping and other recreational activities, moving furniture, appliances and other personal property, to carrying tools and equipment to and from construction sites and storage at the sites. A trailer typically has a pair of hinge supported doors at its rearward end, extending substantially the full height from the deck of the trailer to its roof. The doors are securely closed by a vertically extending rod, with a lever or handle attached to the rod and pivotable into a door closing position. A latch and lock, e.g. a padlock, can be used to secure the handle in the door closing position. Some trailers include additional, single hinge supported doors along one of their side walls, with a similar vertical rod, handle and latch arrangement to secure the door.
[0003] For many uses, this locking arrangement is sufficient. However, whenever a trailer is left unattended for an appreciable amount of time, for example at a construction site or other remote location, it becomes susceptible to attempts to gain unauthorized entry, increasing the risk of theft or vandalism to the contents of the trailer.
[0004] In recognition of the need for better security, systems have been developed to augment the protection provided by the rod/handle arrangements. For example, U.S. Pat. No. 5,934,116 (Moore) shows a system with two block sections, one secured to each door of a trailer, and a rectangular bar contained in the block sections and spanning the distance between them. U.S. Pat. No. 6,834,896 (Smith) shows tubular locking assemblies designed to prevent rotation of the vertical rods away from the positions that secure the doors.
[0005] Locking devices designed to prevent entry into vehicles are shown in U.S. Pat. No. 6,349,573 (Johnson) and U.S. Pat. No. 5,035,458 (Boensch). With regard to stationary containers, U.S. Pat. No. 4,418,551 (Kochackis) and U.S. Pat. No. 5,108,166 (Klix) show cages designed to enhance vending machine security by completely surrounding the vending machines.
[0006] Although the foregoing systems may be suitable for a variety of uses, they fail to address certain objects achieved by trailer locking systems configured according to the present invention.
SUMMARY OF THE INVENTION
[0007] The present invention has several aspects, each directed to one or more of the following objects:
[0008] The first of these objects is to provide a trailer locking system that does not require any modification of the trailer, and does not require a permanent mounting of locking system hardware to the trailer.
[0009] Another object is to provide a trailer locking system that a single individual can easily configure into a secure and positive locking engagement with the trailer.
[0010] A further object is to provide a universal locking system readily useable with a variety of trailers in a given size range.
[0011] Yet another object is to provide a trailer locking system having additional utility as a carrier.
[0012] One aspect of the invention is a locking system for securing a trailer having a substantially horizontal deck, a perimeter wall extending upwardly from the deck, a roof cooperating with the deck and perimeter wall to enclose an interior of the trailer, an entrance along the perimeter wall, a door mounted to the perimeter wall for closing the entrance, and wheels or other means of supporting the deck above ground.
[0013] The locking system includes a plurality of substantially rigid frame members. A coupling structure is provided for releasably securing the frame members to one another to form a trailer locking frame. A support structure, mounted to the trailer locking frame, is adapted to support the locking frame in a locking position in substantially surrounding relation to a perimeter wall of a trailer in close proximity to the perimeter wall, and with a portion of the locking frame extending across an entrance of the trailer to prevent the opening of a door at the entrance to gain entry into the trailer so long as the frame members are so secured. A retaining component is mounted with respect to the trailer locking frame and extends beneath a deck of the trailer when the locking frame is in the locking position, thereby being disposed to engage the deck in response to movement of the locking frame upwardly from the locking position to prevent further upward travel of the locking frame relative to the trailer.
[0014] Several advantages arise from the fact that the locking frame in the locking position substantially surrounds, but does not necessarily contact, the perimeter wall. There is no need for a tight fit or exact alignment of the locking frame with the perimeter wall or any particular segment of the perimeter wall, such as the segment where a trailer door is located. Consequently there is no need modify or adapt the trailer to accommodate the locking frame, and no need to mount locking system hardware to the trailer. In addition, the locking frame is usable with virtually any trailer within a given size range.
[0015] The preferred support structure is a plurality of elongate support legs extending downwardly from the locking frame, more particularly from selected frame members. The preferred retaining component comprises substantially horizontal extensions fixed to bottom portions of the support legs. This allows a frame member and its associated legs and extensions to be configured as a self-standing structure. For an individual working alone, this considerably eases the task of assembling the frame members into the locking frame.
[0016] Another aspect of the invention is a trailer locking apparatus. The apparatus includes a plurality of substantially rigid frame members adapted for assembly into a trailer locking arrangement. A plurality of coupling plates are mounted integrally to free end portions of the frame members and adapted to form pairs of adjacent confronting coupling plates when the frame members are assembled into the locking arrangement. The coupling plates have respective locking apertures, and the locking apertures of each confronting coupling plate pair are alignable to receive a locking device for forming a releasable locking engagement of the coupling plate pair. A first coupling plate of each coupling plate pair supports a locking pin that extends longitudinally away from the first coupling plate and is spaced apart transversely from its associated locking aperture. A second coupling plate of the coupling plate pair includes a pin-receiving aperture spaced apart transversely from its associated locking aperture to receive the locking pin and thereby prevent any substantial rotation of the coupling plates relative to one another about longitudinal axes when the coupling plates are in said releasable locking engagement.
[0017] Thus, confronting pairs of the coupling plates cooperate to enhance security of the trailer locking apparatus through greater resistance to rotation of adjacent frame members relative to one another. This improves security, not only in free standing locking systems, but also for systems in which at least one of the frame members is permanently fixed to the trailer.
[0018] Preferably the frame members along their free end portions have longitudinal axes, and the coupling plates are mounted with their major planes perpendicular to the longitudinal axes. This positions the coupling plates for more effective resistance to frame member rotation.
[0019] Yet another aspect of the present invention is a trailer lock and carrier system for use with a trailer having a deck, a perimeter wall extending upwardly from the deck, a roof cooperating with the deck and perimeter wall to enclose an interior of the trailer, an entrance along the perimeter wall, and a door mounted to the perimeter wall for closing the entrance.
[0020] The lock and carrier system includes a plurality of substantially rigid frame members. A coupling structure is provided for releasably securing the frame members to one another to form a trailer locking frame. The system further includes a locking frame support assembly including an upright support member fixed at a lower end region thereof to a selected one of the frame members, and a top support member fixed to an upper end region of the upright support member. A mounting component is adapted to mount the locking frame support assembly integrally to a trailer with the top support member extending over a roof of the trailer and with the upright support member extending downwardly from the top support member along a perimeter wall of the trailer to locate the selected frame member in close proximity to the perimeter wall, thereby to support the locking frame in a locking position with a portion of the locking frame extending across an entrance of the trailer to prevent the opening of a door at the entrance to gain entry into the trailer, so long as the frame members are so secured.
[0021] Preferably the portion of the locking frame extending across the trailer entrance is composed of a frame member other than one of the selected frame members. Then, a user can gain access to the trailer by disconnecting a single frame member from the trailer locking frame, in lieu of disassembling the frame. Accordingly it is more convenient to lock and unlock the system. The locking frame is carried by the trailer and disposed completely above the ground. As a result, the trailer can be used to transport cargo without removing or altering the system. In a particularly preferred embodiment, the locking frame support assembly comprises a forward subassembly and a rearward subassembly, each with a top support member extending substantially horizontally over the roof, and first and second upright support members extending downwardly along the perimeter wall from opposite end regions of the top support member. In this arrangement, the top support members cooperate to provide a roof top carrier for equipment and supplies, for example ladders, pipe sections and lumber.
[0022] Thus in accordance with the present invention, trailer locking systems provide enhanced security against unauthorized entry, are more convenient to use, and can be adapted to different styles of trailers within a given size range without the need to mount hardware to or otherwise modify the trailer itself. In addition, as exemplified in alternative embodiments, locking systems with components permanently attached to trailers can provide rooftop carriers.
IN THE DRAWINGS
[0023] Further features and advantages will become apparent upon consideration of the following detailed description and drawings, in which:
[0024] FIG. 1 is a perspective view of a trailer and a trailer locking system configured according to the present invention;
[0025] FIG. 2 is a side elevation of the trailer and locking system;
[0026] FIGS. 3-5 are perspective views showing individual sections of the locking system;
[0027] FIG. 6 is a partially sectioned side view illustrating a coupling of the locking system components;
[0028] FIG. 7 is a perspective view showing a trailer and an alternative embodiment trailer locking system;
[0029] FIG. 8 is a sectional elevation illustrating the mounting of a locking system component to the trailer;
[0030] FIG. 9 is a perspective view showing the rear portion of a trailer equipped with another alternative embodiment trailer locking system;
[0031] FIG. 10 is a perspective view showing part of the side wall of a trailer equipped with a further alternative embodiment locking system;
[0032] FIG. 11 is a perspective view showing an alternative embodiment coupling plate for joining locking system components; and
[0033] FIG. 12 is an elevational view showing a hinged coupling of locking system components.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] Turning now to the drawings, there is shown in FIGS. 1 and 2 a trailer locking system 16 surrounding and locking a trailer 18 . The trailer has a rectangular trailer body supported above ground by wheels 20 and a hitch 22 , which in use is coupled to a ball or other connector at the rear of a towing vehicle. When not in transit, hitch 22 can be supported above ground by a block 24 as shown in FIG. 2 . The trailer body includes a floor or deck 26 that is horizontal when the trailer is supported as shown, a horizontal roof 28 , and a perimeter wall arrangement extending vertically between the deck and roof. The perimeter wall arrangement includes a front wall 30 , a back wall 32 , and opposite side walls 34 and 36 . A portion of side wall 34 is shown cut away in FIG. 2 , to reveal front wall 30 and side wall 36 .
[0035] Entrances to the trailer interior are formed through side wall 34 and back wall 32 . The back entrance is closed by opposed rear doors 38 and 40 , each supported pivotally by hinges 42 . A portion of door 38 is shown cut away to reveal deck 26 . The rear doors are kept tightly closed by a cam action rod 44 , a handle 46 secured to rod 44 to pivot about an axis perpendicular to the rod length, and a latch 48 designed to capture the handle and maintain the rod in the closed position.
[0036] The side entrance is closable as shown by a side door 50 supported pivotably by hinges 52 , and kept closed by a cam action rod 54 , handle 56 and latch 58 . While padlocks or other locking devices can be secured to latches 48 and 58 to lock the trailer, locking system 16 provides the enhanced security called for when the trailer is left unattended for extended time periods. Trailer locking system 16 is conveniently considered to include two primary functional components: a locking frame that surrounds the trailer, and a support structure for supporting the locking frame at a desired height. The locking system is composed of four sections, three of which incorporate both locking frame and support structure functions.
[0037] A front section 60 ( FIG. 3 ) includes a C-shaped locking frame member 62 with a medial region 64 and opposed, parallel end regions 66 and 68 . Frame member 62 is supported by a pair of vertical legs 70 and 72 with respective horizontal leg extensions 74 and 76 . As seen in FIG. 2 , the leg extensions are directed inwardly beneath the trailer body when locking system 16 is secured around the trailer. Thus, the leg extensions are positioned to encounter deck 26 in response to vertical travel of the locking frame relative to the trailer, to prevent further vertical travel. Due to leg extensions 74 and 76 , the locking frame cannot be lifted sufficiently to remove it from the trailer.
[0038] Another useful feature of leg extensions 74 and 76 is that they are capable of supporting section 60 upright as shown in FIG. 2 when the front section is separated from the rest of locking system 16 . This “stand alone” feature provides for a more convenient assembly of the system components into the locking arrangement around trailer 18 , especially for an individual working alone.
[0039] At the free ends of end regions 66 and 68 are coupling components, including respective coupling plates 78 and 80 , and respective stabilizing pins 82 and 84 . The pins are fixed to their associated plates and extend longitudinally, i.e. in the length direction of the end regions, while the coupling plates are oriented transversely to more effectively resist rotation about longitudinal axes. A locking aperture 85 is formed through each coupling plate.
[0040] As seen in FIG. 4 , a back section 86 consists essentially of a C-shaped frame member 88 with a medial region 90 and opposed, parallel end regions 92 and 94 . Section 86 does not include any support structure. Coupling components at the free ends of regions 92 and 94 include a coupling plate 96 and stabilizing pin 98 associated with end region 92 , and a coupling plate 100 and stabilizing pin 102 associated with end region 94 . The coupling plates and pins are oriented relative to their associated end sections as previously described. Locking apertures 101 are formed through coupling plates 96 and 100 .
[0041] FIG. 5 shows a side section 104 including an elongate frame member 106 , coupling plates 108 and 110 at the opposite ends of frame member 106 , and a vertical leg 112 depending downwardly from the frame member. Leg 112 does not have a horizontal leg extension, although such extension can be formed optionally, as indicated in broken lines at 114 . No stabilizing pins extend away from frame member 106 . Rather, each coupling plate is provided with a pin receiving aperture as indicated at 116 for coupling plate 108 . Locking apertures 118 are formed through coupling plates 108 and 110 .
[0042] The system components further include another side section 120 substantially identical to side section 104 , with a frame member 122 and a vertical leg 123 to support the frame member.
[0043] In all of the sections, the frame members, legs and leg extensions preferably are formed of tubular steel, with elongate linear tubing sections welded together to form the L-shaped and C-shaped members. The coupling plates likewise are formed of steel, and are welded to their associated frame members. Other suitable materials include stainless steel, steel alloys, aluminum, fiberglass, and high tempered plastics.
[0044] Returning to FIGS. 1 and 2 , locking system sections 60 , 86 , 104 and 120 are releasably joined by locking devices such as padlocks 124 to secure the trailer. Frame members 62 , 88 , 106 and 122 cooperate to form a rectangular locking frame that surrounds the trailer, supported at the desired height by legs 70 , 72 , 112 and 123 . Frame member 88 prevents entry into the trailer through rear doors 38 and 40 , while frame member 106 denies entry through side door 50 .
[0045] FIG. 6 illustrates the coupling of frame member 88 with frame member 106 . The other system couplings are substantially identical. Just prior to coupling, end region 94 and frame member 106 are positioned to confront one another with their longitudinal axes substantially coincident, as shown. Then, as the frame members are moved longitudinally toward each other, pin 102 enters pin receiving aperture 116 to maintain the alignment during continued movement, until coupling plates 100 and 108 engage. At this point it may be necessary to rotate one of frame members 88 and 106 about the substantially coincident longitudinal axes, to bring locking apertures 101 and 118 into alignment. With the locking apertures aligned, a padlock or other suitable locking device is directed through both locking apertures. Preferably the diameter of aperture 116 exceeds the diameter of pin 102 only slightly, and the diameters of locking apertures 101 and 118 similarly only slightly exceed the captured shaft of the locking device. In that case, the locking device shaft and pin 102 cooperate to prevent any substantial rotation or transverse movement of frame members 88 and 106 relative to one another. Pin 102 , acting in combination with the locking device, considerably strengthens the coupling by preventing the adjacent members from rotating relative to one another about the longitudinal axes.
[0046] FIG. 7 illustrates an alternative embodiment trailer locking system 126 mounted to a trailer 127 similar to trailer 18 . Locking system 126 includes locking frame support structure in the form of two C-shaped support members 128 and 130 . Support member 128 includes a horizontal medial region 132 , and vertical end regions 134 and 136 depending downwardly from opposite ends of the medial region. Similarly, support member 130 includes a medial region 138 and two vertical end regions 140 and 142 .
[0047] A rectangular locking frame of system 126 is composed of a C-shaped front frame member 144 , a C-shaped back frame member 146 , linear side frame members 148 and 150 disposed along a side wall 152 of the trailer including a side door 154 , and a side frame member 156 on the opposite side of the trailer. Adjacent frame members are releasably coupled by coupling plates and locking devices in the manner previously described.
[0048] Locking system 126 is mounted permanently to trailer 127 in the sense that it is secured through mounting structure to the trailer walls using spacers and carriage bolts. FIG. 8 is a partial sectional view, taken along a vertical plane through the trailer behind support member 130 . A spacer 158 , preferably tubular steel, maintains end region 142 of support member 130 horizontally spaced apart from side wall 152 . Carriage bolts 160 extend through the end region, spacer and side wall to secure these components while locating medial region 138 in vertically spaced apart relation to a roof 162 of the trailer.
[0049] With reference to FIG. 7 , vertical end region 142 is further secured by a second spacer 164 and carriage bolts 160 . Vertical end region 140 is similarly secured in spaced apart relation to the opposite side wall.
[0050] Vertical end regions 134 and 136 can be secured to the side walls in similar fashion, or alternatively can be equipped with spacers forming a frictional engagement with the trailer side walls. This latter approach allows at least limited sliding or pivoting of vertical end regions 134 and 136 to provide clearance when stabilizing pins are used to couple adjacent frame members.
[0051] Because locking system 126 is substantially permanently attached to trailer 127 rather than supported by the ground, there is no need to disassemble the system to allow the trailer to be moved to another location. The system is transported in place, along with the trailer. Further, medial regions 132 and 138 cooperate to provide a pair of rails extending across the roof of the trailer, to function as a trailer top carrier for transporting equipment and materials, e.g. ladders, pipe sections and lumber. In addition, equipment and supplies can be secured to vertical end regions 134 , 136 , 140 and 142 for transport with the trailer.
[0052] FIG. 9 illustrates the rear portion of a trailer 166 equipped with an alternative embodiment trailer locking system 168 . Locking system 168 includes a linear side frame member 170 mounted to a side wall 172 of the trailer by welding the frame member to a tubular steel spacer 174 which is anchored to the side wall using carriage bolts 176 . A linear side frame member 178 is mounted to the opposite side wall in similar fashion. The locking system further includes a C-shaped frame member 180 including a medial region 182 and opposed, parallel end regions 184 and 186 . To secure the trailer against entry through rear doors 188 and 190 , end regions 184 and 186 are releasably coupled to side frame members 170 and, 178 in the manner previously described.
[0053] FIG. 10 illustrates a further alternative embodiment trailer locking system 192 for securing a side door 194 of a trailer 196 . The locking system includes a relatively short linear frame member 198 and a similar frame member 200 , mounted to a side wall 202 of the trailer with carriage bolts directed through respective mounting plates 204 and 206 . A C-shaped frame member 208 includes opposite end regions attached releasably to frame members 198 and 200 in the manner previously described. The frame member secures side door 194 , yet also provides clearance for hardware such as the latching bar and hinges.
[0054] FIG. 11 illustrates an alternative embodiment coupling plate 210 attached to the end of a frame member 212 . Coupling plate 210 is formed with two locking apertures 214 and 216 . Frame member 212 , and an adjacent frame member having a similar coupling plate, are releasably secured to one another with two locking devices. With reference to FIG. 7 , an advantage of this coupling approach is that no clearance is required for stabilizing pin, for example when inserting or removing frame member 150 to prevent or allow the opening of side door 154 .
[0055] FIG. 12 illustrates a hinge 218 for coupling adjacent frame members 220 and 222 . In any of the foregoing locking systems, hinged couplings can be employed in lieu of the coupling plate/stabilizing pin arrangements, to reduce the number of padlocks or other locking devices required. In locking systems 168 and 192 , only one of the coupling plate/pin arrangements can be replaced with a hinge, while several hinges can be substituted into each of systems 16 and 126 .
[0056] Thus in accordance with the present invention, trailer locking systems can reduce the risk of unauthorized entry, can be used to secure different trailers within a given size range, and are convenient to use. The locking systems include embodiments that require no mounting of hardware or other modifications to the trailer, and other embodiments in which the locking system also functions as a carrier. | A trailer locking system includes separate sections releasably coupled to provide locking frames that secure trailers against unauthorized entry through side doors and rear doors. The sections include frame members adapted for releasable coupling to other frame members to form the locking frames, along with support structure for selectively locating the locking frames relative to the trailer body. The locking frames can surround their associated trailers, or may span the width of the doors they are intended to secure. Locking frames that surround the trailers can be supported by ground engaging legs independently of the trailer, or by support members along the trailer top and sides that additionally provide a carrier for equipment and supplies. Adjacent frame members are releasably joined by coupling plates and stabilizing pins mounted to selected coupling plates. Other coupling plates have pin-receiving apertures, and all coupling plates have locking apertures to accommodate padlocks or other locking devices. | 4 |
BACKGROUND OF THE INVENTION
The present invention is directed to an apparatus for cutting a length of material as it flows from a machine and, more particularly, to a radius blade cutting apparatus which automatically cuts a length of material upon completion of a manufacturing operation. The invention is especially useful with sewing machines as used in the manufacture of garments.
In manufacturing a garment, various specialized sewing machines are used for efficient assembly of particular pieces of cloth and for stitching of particular seams. For example, in sewing a binding tape or other strip of material over a raw seam of a partially completed garment or workpiece, a specialized machine may feed the strip of material from a spool into a presser foot for stitching to a workpiece which is passed under the presser foot. This type of sewing machine may be equipped with one of the available cutting devices to permit automatic cutting of the workpiece from the excess strip of material and the excess thread after stitching of the workpiece is completed.
Generally, two types of devices for automatically cutting the workpiece from the excess strip of material and the excess thread are available. In one, a chopper blade and anvil are mounted upon the head and arm of the sewing machine, respectively, so as to chop the material upon actuation of a fluid cylinder. In another, a knife blade is pivotally mounted on the head of the sewing machine so as to engage a stationary blade mounted on the arm of the sewing machine upon actuation of a fluid cylinder. Generally, other types of cutting devices are not used in such machines due to the limited space available and the need to leave the throat of the sewing machine unobstructed for manipulation of the workpiece under the presser foot.
Although these available automatic cutting devices have significantly improved the efficiency of various garment manufacturing operations, the devices are unreliable in numerous sewing operations. Also, the chopper blade and anvil type device may break the arm or a portion of the arm off the sewing machine. Further, the knife blade type device is difficult to align and maintain in necessary alignment because the blades are mounted upon separate parts of the machine. And, both types of devices result in considerable expense and downtime when damaged or worn out cutting surfaces are renewed. Additionally, in many particular sewing machine applications, there is inadequate space for such devices without interference with operation of the machine.
It is, therefore, an object of the present invention to provide an apparatus for automatically cutting a workpiece from the excess strip of material sewn thereto without the difficulties inherent with the blade and anvil or the pivoting blade and stationary blade devices now available.
Another object of the present invention is to provide a cutting apparatus which is suitable for many diverse applications, particularly those machine applications where there is inadequate space for the available cutting devices, for cutting a strip of material as it flows from a machine.
It is still another object of the present invention to provide a cutting apparatus for cutting a strip of material as it flows from a machine such that positive cutting is achieved with a minimum of alignment requirements and without risk of injury to an operator of the machine.
It is still another object of the present invention to provide a cutting apparatus having reversible blades and other features to minimize machine downtime and other expenses of forming, installing, and renewing the cutting surfaces.
SUMMARY OF THE INVENTION
The present invention is directed to an improved processing machine of the type which processes a length of material. A pair of blade members is rotatably mounted on a common blade axis which is substantially parallel to and spaced from the length of material to be cut. Each of the blade members includes a cutting surface which is directed substantially radially with respect to the blade axis, such blade members being characterized as "radius blades." Each blade member is rotatable between a rest position allowing passage of the material and a cutting position. The cutting apparatus further includes moving means for effecting coordinated counter-rotation of the blade members from the rest position to the cutting position such that the cutting surfaces cooperate to snip the length of material by a shearing action.
In the preferred embodiments described herein, the moving means includes elongated blade driving arms and other linkage means operable to ensure that each of the blade members rotates substantially simultaneously from the rest position to the cutting position. Each of the blade driving arms is pivotally mounted at one end upon an off-set, crank portion of a blade member and is pivotally joined to the other blade driving arm at the other end upon a pivot pin which is movable toward and away from the blade member axis by power means. The blade members are preferably flat, and, because no blade angle or relief is used in forming the cutting surfaces, the blades can be simply and economically formed and sharpened. Further, the blades are readily reversible so as to provide either two or four alternative cutting surfaces upon each blade.
The apparatus of the present invention can be mounted upon a sewing machine in combination with sensing and actuating means to provide automatic cutting of a workpiece from an excess strip of material and the excess thread following a sewing operation. As shown by the particular embodiments described herein, the present invention can be adapted to the limited space available upon specialized forms of sewing machines to provide the desired automatic cutting. Further, the apparatus can include simple guard devices to shield an operator from the movement of the blade members and the linkage means without interfering with the automatic cutting or sewing operations. The cutting apparatus can be conveniently powered by a fluid cylinder, a solenoid, or other similar power means to effect positive cutting.
As a result of the present invention, a strip of material flowing from a machine such as a sewing machine can be cut reliably and automatically without the need for constant realignment of blade members as is typical of currently used pivoting blade and stationary blade type devices. Unlike the anvil and blade type devices now used, the cutting apparatus of the present invention does not have a tendency to break the end off the arm of the machine. Further, because the cutting surfaces of the blade members are directed substantially radially with respect to the blade axis, the strip of material to be cut does not tend to slide along the blade members and away from the blade axis as would occur with a more conventional scissor-like design having blades which are not radially directed.
Further objects, features, and advantages of the present invention will become apparent from a consideration of the following description, the appended claims, and the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a tape shoulder machine equipped with a first preferred embodiment of the present invention, the safety guard having been removed to show the cutting apparatus;
FIG. 2 is a front elevation of portions of the tape shoulder machine of FIG. 1, with portions broken away, showing the blade members of the embodiment in the rest position;
FIG. 3 is a right elevation of portions of the sewing machine of FIG. 1, partially in section, showing the blade members of the embodiment in the rest position;
FIG. 4 is a right elevation corresponding to the view of FIG. 3 but showing the blade members of the embodiment in an intermediate position between the rest and cutting positions;
FIG. 5 is a right elevation corresponding to the view of FIG. 3 but showing the blade members of the first embodiment in the cutting position;
FIG. 6 is a detail view of one of the blade members of the embodiment of FIGS. 1-6;
FIG. 7 is a front elevation of a second embodiment of the present invention as mounted upon a flatlock machine, portions of which are shown in phantom;
FIG. 8 is a bottom view of the embodiment of the present invention shown in FIG. 7;
FIG. 9 is a sectional view of the embodiment shown in FIG. 7 taken along line 9--9 of FIG. 7.
FIG. 10 is a sectional view of the embodiment shown in FIG. 7 taken along line 10--10 of FIG. 7;
FIG. 11 is a perspective view of a third embodiment of the present invention showing portions of a flatlock machine upon which the embodiment is mounted;
FIG. 12 is a sectional view of the embodiment shown in FIG. 11 taken along line 12--12 of FIG. 11;
FIG. 13 is a sectional view of the embodiment shown in FIG. 11 taken along line 13--13 of FIG. 11; and
FIG. 14 is a sectional view like that of FIG. 13 but showing the embodiment of FIG. 11 in the cutting position.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to the drawings, a preferred embodiment of the cutting apparatus of the present invention, indicated generally by the numeral 10, is shown in FIG. 1 as mounted upon a tape shoulder machine, indicated generally by the numeral 12.
The tape shoulder machine 12 is a specialized form of sewing machine which includes a machine head 14 at the front of the machine, a drive pulley 16 at the back of the machine, and a machine base 18 which is supported by conventional means at a convenient working height. Other portions of the tape shoulder machine 12 are a machine neck 20, a machine throat 22, and a drive belt 24 connected to a motor, not shown. A sewing needle 26 receives thread 28 from a thread guide 30 and passes the thread 28 vertically through a presser foot 32.
Unlike more conventional sewing machines, the tape shoulder machine 12 includes a long cantilevered machine arm 34, extending from the right end of the machine to the presser foot 32, which is particularly adapted for sewing a strip of fabric tape 36 upon the shoulder seam of a garment. The fabric tape 36 is fed from a tape spool, not shown, through a tape guide 38, to a tape folding device 40 which folds the fabric tape 36 to prevent fraying of the fabric tape 36 on the completed garment. The fabric tape 36 then passes under the presser foot 32 in a direction from right to left as shown in FIG. 1.
In the operation of the tape shoulder machine 12, a workpiece such as a partially completed shirt is manipulated into the machine at the machine throat and over the machine arm 34 while the presser foot 32 is in a raised position. A worktable 42 assists in supporting the workpiece. The presser foot 32 is then lowered upon the shoulder seam over which the fabric tape 36 is to be sewn, and a feed dog, not shown, under the presser foot 32 pulls the workpiece to the presser foot 32 upon activation of the feed dog by an operator. The operator guides the workpiece into the presser foot 32 such that the fabric tape 36 is stitched over the shoulder seam of the workpiece.
Operation of the feed dog and the sewing needle 26 are continued after stitching of the fabric tape 36 to the workpiece is completed. As shown in FIG. 1, this creates an umbilical-like connection 46 between the completed workpiece 48 and the fabric tape 36 and the thread 28. The umbilical-like connection 46 is then cut adjacent the presser foot 32 to separate the completed workpiece 48 from the excess fabric tape 32 and the excess thread 28, leaving a short pigtail 50 of folded and stitched fabric tape which is trimmed in a later manufacturing operation.
The cutting apparatus 10 of the present invention is mounted directly upon the machine head 14 by an angle mounting bracket 52 which is fixed by cap screws 54. The cap screws 54 may also be used to secure the tape guide 38 to the machine head 14 by means of a tape guide mounting bracket 56. A generally vertical support member 58 is mounted upon the angle mounting bracket 52 by cap screws 60 so as to be generally perpendicular to and slightly above the path of the stitched fabric tape 36 as it leaves the presser foot 32 and moves from right to left as shown in FIG. 1.
As shown in greater detail in FIGS. 2 and 3, the support member 58 provides a stationary threaded mounting for a pivot screw 62 which is aligned generally parallel to and somewhat above the path of the stitched fabric tape 36. A pair of pie shaped blade members 64 and 66 are rotatably mounted at their apex points upon the pivot screw 62. A helical compression spring 68 is positioned under the head of the pivot screw 62 to provide adjustable biasing of the blade member 64 against the blade member 66. Preferably, brass washers 70 and 72 are positioned between the support member 58 and the blade member 64 and between the blade member 66 and the compression spring 68, respectively, to provide bearing surfaces. Steel washers 74 and 76 are provided at the ends of the compression spring 68, as shown in FIG. 2.
Actuation of the blade members 64 and 66 from the rest position shown in FIGS. 2 and 3 is provided by a fluid cylinder 78 which is mounted upon a horizontal cylinder mounting bracket 80 welded to the support member 58. A piston rod 82 is displaced downward through a cylinder mounting collar 84 upon the application of fluid pressure to the fluid cylinder 78. A push rod 86 is threaded over the end of the piston rod 82 and passes through both legs of a U-shaped guide block 88 which is fixed to the vertical support plate 58 by machine screws. A push rod yoke 90 is fixed to the lower portion of the push rod 86, and bumper stops 92 and 94 are provided between the push rod assembly and the upper and lower surfaces of the guide block 88, respectively.
Two blade driving arms 96 and 98 are pivotally mounted upon the push rod yoke 90 by means of a common pivot pin 100 which is aligned parallel to the pivot screw 62. The blade driving arms 96 and 98 extend downward from the pivot pin 100 and are pivotally mounted upon the blade members 64 and 66 by blade pivot pins 102 and 104, respectively. The fluid cylinder 78 is mounted upon the support member 58 so as to be directed perpendicular to the path of the stitched fabric tape 36 as it leaves the presser foot 32. It will be appreciated that the fluid cylinder 78, operating through the piston rod 82 and push rod 86, moves the common pivot pin 100 toward the pivot screw 62 in response to fluid pressure.
The blade pivot pins 102 and 104 are off-set with respect to a line through the common pivot pin 100 and the pivot screw 62 such that the blade members 64 and 66 serve as cranks to simultaneously effect counterrotation of the blade members 64 and 66 in response to vertical displacement of the common pivot pin 100. Arm yoke plates 106 and 108 are fixed by machine screws to the blade driving arms 96 and 98, respectively, to provide increased support for the blade members 64 and 66. The arm yoke plates 106 and 108 help maintain alignment of the blade members 64 and 66 in a plane which is perpendicular to the path of the stitched fabric tape 36 as it leaves the presser foot 32.
The blade members 64 and 66 include respective cutting surfaces 110 and 112 which are directed substantially radially with respect to the axis of the pivot screw 62. Upon actuation of the fluid cylinder 78, the blade members 64 and 66 are rotated in opposite directions from the rest position shown in FIGS. 2 and 3 to the intermediate position shown in FIG. 4 and, thereafter, to the cutting position shown in FIG. 5. In moving to the cutting position, the cutting surfaces 110 and 112 penetrate a narrow channel 114 formed in an extension 115 of the machine arm 30 so as to intersect the path of the stitched fabric tape 36 as it leaves the presser foot 32.
Because the cutting surfaces 110 and 112 are directed substantially radially with respect to the axis about which they pivot, the cutting surfaces 110 and 112 effect shearing along their entire length almost simultaneously so as to reduce the tendency of the umbilical-like connection 46 to slide along the blade members 64 and 66 instead of being cut by the blade members 64 and 66. Thus, the cutting action is significantly different from that of a conventional pair of scissors. The arm yoke plates 106 and 108 are flattened along their inside edges 116 and 118, as shown in FIG. 5, to provide clearance for the blade driving arms 96 and 98 in the rest position and to provide a stop ensuring that the blade pivot pins 102 and 104 are maintained in the desired off-center position.
Material puller rollers 120 and 122 are counterrotated in the directions indicated by arrows in FIG. 2 to prevent slack and maintain the umbilical-like connection 46 in position beneath the blade members 64 and 66 after stitching of the workpiece 48 is completed. The roller 120 is biased against the stitched fabric tape 36 and the roller 122 by a helical compression spring 124 acting through a push rod 126 having a yoke 128. The push rod 126 passes through the legs of a U-shaped guide block 128 which is fixed to the machine head 14 or, alternatively, to the support member 58. A fluid cylinder 130, fixed to the guide block 128, engages an arm 132 to selectively raise the roller 120. Rotation of the roller 120 is provided by a flexible cable 134.
The blade members 64 and 66 are immediately returned to the rest position upon cutting of the umbilical-like connection 46 by retraction of the push rod 86 and the piston rod 82. This retraction of the blade members 64 and 66, in combination with the raising of the roller 120 by the fluid cylinder 130, permits a second workpiece to be fed into the machine throat 22 and over the machine arm 34 immediately following completion of a first workpiece. In the preferred embodiment shown, a push-type air cylinder is used which includes an integral retraction spring to retract the piston rod 82 and the blade members 64 and 66.
Photosensors 136 and 138 are fixed to the support member 58 by angle mounting brackets 140 and 142 and are directed against reflective targets 144 and 146, respectively. The photosensors 136 and 138 sense the absence of the workpiece 48 and thereupon trigger actuation of the fluid cylinder 78. The photosensors 136 and 138 also serve as safety devices by ensuring that the blade members 64 and 66 are not actuated when an object is adjacent to the folded and stitched strip of fabric tape 32 and in the path of the cutting surfaces 110 and 112. To further prevent injury to an operator, a shield 148 is mounted over the support plate 58 so as to enclose the blade driving arms 96 and 98 and the blade members 64 and 66, leaving only a narrow opening 150 for manipulation of the workpiece 48.
FIG. 6 shows the configuration of the blade member 64 in greater detail. An arcuate portion 152, the cutting surface 110, and an alternative cutting surface 154 define the generally pie-shaped perimeter. The cutting surface 110 and the alternative cutting surface 154 are radial with respect to the arcuate portion 152 and are in alignment with an apex hole 156 for mounting the blade member 64 upon the pivot screw 62. A circular portion 158 surrounding the apex hole 156 provides a bearing surface for the blade member 66 and the brass washer 72 and serves to maintain alignment of the blade member 64 in a plane perpendicular to the stitched fabric tape 36. A first circumferential hole 160 receives the pivot pin 104 of the blade driving arm 96 to rotate the cutting surface 110 into cutting position.
Preferably, the blade member 64 is formed of flat tool steel which is heat treated and surface ground. The thickness of the blade member 64 is uniform and the cutting surface 110 and the alternative cutting surface 154 are ground at 90° to the orientation of the blade member 64, no relief or angle being required. A second circumferential hole 162, symmetrical with the first circumferential hole 60, permits the blade member 64 to be reversed front to back (from the position shown in FIG. 6) upon the pivot pin 104 and the pivot screw 62. Two additional cutting positions result if the blade driving arms 96 and 98 are also repositioned. In this way, the blade member 64 provides four alternative 90° cutting edges which can be used sequentially to renew sharpness of the blade member without replacement of the blade member. The blade member 66 is identical to the blade member 64 so as to further simplify forming, installing, and renewing of the cutting edges.
FIG. 7 shows a second embodiment of the cutting apparatus of the present invention, indicated generally by the numeral 164, mounted upon a flatlock machine shown in phantom and indicated generally by the numeral 166. The flatlock machine 166 includes a presser foot 168 which receives a strip of fabric tape 170 and folds the fabric tape 170 with a workpiece, not shown, which is passed under the presser foot from right to left. A needle penetrates the presser foot 170 for stitching the fabric tape 170 to the workpiece to form a flat seam.
The cutting apparatus 164 is similar to the first embodiment except that it includes a horizontal extension to clear the portions of the flatlock machine which extend to the left of the presser foot 168 as shown in FIG. 7. The cutting apparatus 164 includes blade members 172 and 174, blade driving arms 176 and 178, and a fluid cylinder 180 which operates through a push rod 182. A push rod yoke 184 includes a common pivot pin 186 upon which the blade driving arms 176 and 178 are pivotally mounted. The cutting apparatus 164 is mounted upon an angle bracket 190 and vertical mounting plates 192, 194, and 196 which are rigidly supported relative to the flatlock machine 166 by conventional means.
Unlike the first embodiment, the cutting apparatus 164 includes hinge members 198 and 200, as shown in FIGS. 8 and 9. The hinge members 198 and 200 serve as spacers between the blade members 172 and 174 and the respective blade driving arms 176 and 178 to permit the blade members to be positioned adjacent to the presser foot 168. A hinge pin 202 provides the stationary pivot point about which the blade members 198 and 200 rotate. The hinge pin 202 is threaded into the vertical support plate 196 and is further supported by a gusset 204 which is welded to the vertical mounting plate 196 and which includes an eye 206 through which the hinge pin 202 passes.
The blade members 172 and 174 and the blade driving arms 176 and 178 are fixed to the respective hinge members 198 and 200 by machine screws. Pivot portions 206 and 208 of the hinge members 198 and 200, respectively, straddle the eye 206 of the gusset 204 to further locate the hinge members 172 and 174. A helical compression spring 210 is adjustably compressed by an adjustment nut 212 to bias the blade member 172 against the blade member 174 to ensure positive cutting. A channel 214 in an extended arm 216 of the flatlock machine 166 is provided to receive the blade members 176 and 178 in the cutting position.
As shown in FIGS. 9 and 10, the hinge members 198 and 200 and the blade members 172 and 174 may be made flat along their respective upper surfaces 216, 218, 220, and 222 to provide clearance for the flatlock machine 166. The cutting surfaces 224 and 226 are approximately radial with respect to the hinge pin 202 to provide a shearing action similar to that of the first embodiment. The construction of the blade members 172 and 174 is similar to that of the blade members 64 and 66 of the first embodiment, thereby providing alternative 90° cutting edges on each of the cutting surfaces 224 and 226. However, due to the flat upper surfaces 220 and 222, only two, not four, alternative cutting edges are provided upon each of the blade members 172 and 174.
FIGS. 11-14 show a third embodiment of a cutting apparatus of the present invention, indicated generally by the numeral 228, as used with a flatlock machine. The cutting apparatus 228 is substantially the same as the second embodiment just described in that hinge members 230 and 232 serve as spacers between two blade driving arms 234 and 236 and blade members 238 and 240, respectively. The blade members 238 and 240 are counter-rotated into a channel 242 of the flatlock machine arm 244 to shear a stitched fabric tape 246 as it emerges from a presser foot 248. Actuation is provided by a fluid cylinder 250, piston rod 252, yoke 254, and pivot pin 256, upon which the blade driving arms 234 and 236 are mounted.
Unlike the second embodiment, the cutting apparatus 228 features an adjustment nut 258 which is located away from the blade members 238 and 240 and the hinge members 230 and 232. In this way the blade member 238 can be adjustably biased against the blade member 240 by the compression spring 260 from a position above and to the left of the flatlock machine and cutting apparatus 228 as shown in FIG. 11. Instead of being threaded into a vertical mounting plate as in the second embodiment, the cutting apparatus 228 includes a hinge pin 262 which passes freely through a vertical mounting plate 264. A lock nut 266 is provided against the adjustment nut 258 to ensure that adjustment is maintained.
The cutting apparatus 228 also features a relocation of the fluid cylinder 250 and the blade driving arms 234 and 236 to the side of the vertical mounting plate 264 away from the blade members 238 and 240. This requires a key-hole slot 268 in the vertical mounting plate 264 to allow rotation of the hinge members 230 and 232. A gusset bracket 270 includes eye portions 272 and 274 to provide support for the hinge pin 262. The gusset bracket 270 is welded to an angle iron reinforcement 276 which, in turn, is welded to the vertical mounting plate 264 adjacent to the key-hole slot 268. The blade driving arms 234 and 236 include notches 278 and 280, respectively, to provide clearance for the eye portion 272 when rotated to the cutting position shown in FIG. 14.
The blade members 238 and 240 are identical to the blade members 172 and 174 of the second embodiment, thus providing two alternative cutting edges per blade member. The bracketry for supporting the cutting apparatus 228 relative to the flatlock machine is similar to that of the second embodiment. Further, an angle bracket 282, similar to that of the second embodiment, is fixed to the vertical mounting plate 264 to provide a mounting for the fluid cylinder 250. As in the first embodiment, steel washers 284 and 286 are provided at the ends of the helical compression spring 260 and a brass washer 288 is positioned between the blade member 238 and the head of the hinge pin 262. Additionally, the cutting apparatus 164 and the cutting apparatus 228 may be fitted with one or more photosensors and a shield, not shown, similar to those of the first embodiment.
From the foregoing, it should be apparent that a versatile, compact, cutting apparatus for cutting a strip of material flowing from a processing machine has been disclosed. The present invention can cut reliably and automatically without the need for constant realignment of the blade members. The substantially radial cutting surfaces ensure safe and positive cutting and can be adapted for installation upon various processing machines having limited space.
Of course, it should be understood that various changes and modifications to the preferred embodiments described above will be apparent to those skilled in the art. For example, a disc spring could be used in place of the helical compression springs to provide adjustable biasing of the blade members, and other power means such as solenoids could be used in place of the fluid cylinders. Further, in addition to the embodiments described, embodiments of the present invention can be adapted for use with other specialized forms of sewing machines and other processing machines from which a length of material flows. Such changes and modifications can be made without departing from the spirit and scope of the present invention, and it is therefore intended that such changes and modifications be covered by the following claims. | Two blade members are counter-rotated from a rest position to a cutting position in which radially directed cutting surfaces cooperate to snip a strip of material by a shearing action as the strip of material flows from a sewing machine or other processing machine. The blade members are reversible and are biased against each other to ensure positive cutting. A hinge-like linkage permits an offset between the blade members and power means to increase versatility. The cutting apparatus can include sensing means to permit automatic cutting of a completed workpiece from an excess of a strip of material which is sewn to the workpiece during the manufacture of a garment. | 3 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates particularly to a robot provided with a surrounding object distance measurement means to automatically perform desired operation or work while measuring the distance from a work object and an obstacle.
[0003] 2. Description of Related Art
[0004] In many cases, a robot which operates in a coexistence environment with a human is provided with a surrounding object distance measurement means to avoid contact with a surrounding object, and thereby recognizes disposition conditions of the surrounding objects to set a moving route. As one example of the surrounding object distance measurement means, there is a laser scanning range sensor (SOKUIKI sensor) which determines the distance by measuring the time elapsed after a plane is scanned with laser light until the irradiated laser light hits against an object to be measured and the reflected light returns, and in order to widen a scan field, the laser scanning range sensor is often installed in a place around which there is no object which obstructs the scan field. In the prior art, in order to make the scan field of the laser scanning range sensor maximum, the sensor has been attached to the top of a head part, or a front part of a body such as an abdomen part and a chest part of the robot.
BRIEF SUMMARY OF THE INVENTION
[0005] However, in the case of the conventional structure in which a surrounding object distance measurement means, e.g. a laser scanning range sensor, is attached to the top of a head part of a robot as described above, since the head part on which the laser scanning range sensor is mounted is driven by an actuator, the load of the actuator for activating the head part becomes large.
[0006] Further, in the case of mounting the laser scanning range sensor on the head part, the head part is shaped so as not to obstruct a laser scanning plane, and therefore the degree of freedom of design has been remarkably restricted.
[0007] Furthermore, if the laser scanning range sensor is attached to a front part of a body or a chest part as disclosed in JP-A-2005-125457, shielding occurs with high frequency during operation by an arm, which makes it difficult to measure the distance from a work object or a surrounding object.
[0008] An object of the present invention is, in view of the above prior art as described above, to provide a robot having simple structure and further, reducing the load of an actuator of a neck part.
[0009] In order to solve the above problem, the present invention provides a robot characterized in that a surrounding object distance measurement means, e.g. a laser scanning range sensor, is provided adjacently to a neck link which connects a head part and a body part so that a scanning plane of the laser scanning range sensor is provided in parallel with a horizontal plane at an upper central portion of the body part and the center of a scan field is parallel with a roll axis.
[0010] According to the present invention, it is possible to achieve natural appearance, reduction in torque of a neck actuator, expression by various movements of a head part, and simplification of the neck structure, without narrowing a scan field of a surrounding object distance measurement means, e.g. a laser scanning range sensor.
[0011] Other objects, features and advantages of the invention will become apparent from the following description of the embodiments of the invention taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0012] FIG. 1 is a view for explaining the whole of a robot according to an embodiment;
[0013] FIG. 2 is a view for explaining a head part of the robot according to the embodiment;
[0014] FIG. 3 is a view for explaining another configuration of the present invention;
[0015] FIG. 4 is a view for explaining another configuration of the present invention;
[0016] FIG. 5 is a view for explaining pitch axis movement of the head part of the robot; and
[0017] FIG. 6 is a view for explaining roll axis movement of the head part of the robot.
DETAILED DESCRIPTION OF THE INVENTION
[0018] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0019] FIG. 1 is a view showing the whole of a robot of an embodiment, FIG. 2 is a view showing the whole of a head part of the robot of the embodiment, FIGS. 3 and 4 are views showing other configurations, FIG. 5 is a view for explaining movement of a pitch axis of the robot of the embodiment, and FIG. 6 is a view for explaining movement of a roll axis of the robot of the embodiment.
[0020] In the following embodiment, a surrounding object distance measurement means will be described using a laser scanning range sensor as an example. In addition, there is a humanoid robot as an example of a robot to which the present invention is applied, and the description is made using it as an example.
[0021] A robot 101 is composed of a head part 1 , a body part 2 , a left arm 102 , a right arm 103 , a left leg 104 and a right leg 105 . For example, the left leg 104 and the right leg 105 are used for movement of the robot 101 , and the left arm 102 and the right arm 103 are used for work, e.g. for grasping an object. In this embodiment, the head part 1 is located at the top of the robot 101 , and is provided so as to be connected with the body part 2 .
[0022] FIG. 2 shows the structure of the head part 1 , and is a view showing a roll direction (an arrow “Roll”), a pitch direction (an arrow “Pitch”), and a yaw direction (an arrow “Yaw”). A first head actuator 6 , a second head actuator 8 , and a third head actuator 10 have power sources (motors), speed reducers, and angle detectors (rotary encoders or potentiometers) built-in, and drive a connected part.
[0023] The head part 1 consists of: a neck link 3 attached to an upper central portion of the body part 2 so that its longitudinal direction is parallel with the yaw direction; the first head actuator 6 attached to an opposite end in the longitudinal direction of the neck link 3 to connection with the body part 2 so that an output shaft is in parallel with the yaw direction; a first head link 7 oscillated over a predetermined angle only in the yaw direction by the output shaft of the first head actuator 6 ; the second head actuator 8 attached to the first head link 7 so that the direction of an output shaft is in the pitch direction; a second head link 9 oscillated over a predetermined angle only in the pitch direction by the output shaft of the second head actuator 8 ; a third head actuator 10 attached to the second head link 9 so that the direction of an output shaft is in the roll direction; a third head link 11 oscillated over a predetermined angle only in the roll direction by the output shaft of the third head actuator 10 ; a face 12 of the robot attached to one end facing forward in the longitudinal roll direction of the third head link 11 ; and eyes 13 of the robot attached to a design surface of the face 12 of the robot. However, the design surface of the face 12 of the robot does not necessarily require the eyes, but any outside appearance may be adopted as long as its design indicates the direction of the front of the robot. Here, a laser scanning range sensor 4 is provided adjacently to the neck link 3 which connects the head part 1 and the body part 2 and in the upper central portion of the body part 2 so that a laser scanning range sensor scanning plane 5 is provided in parallel with a horizontal plane, and the center of a scan field is parallel with the roll axis.
[0024] In FIG. 2 , the state where the face 12 of the robot of the head part 1 faces in the front forward direction is set as a reference posture. The neck link 3 is disposed in a blind spot of the laser scanning range sensor scanning plane 5 , and does not disturb the view of the laser scanning range sensor 4 at all. By constructing the head part 1 in this manner, the following advantages are brought about.
[0025] First, since the laser scanning range sensor 4 is attached not to the head part 1 which is moved by the three actuators, but to the body part 2 , and therefore the loads of the first head actuator 6 , the second head actuator 8 and the third head actuator 10 for moving the head part 1 become small, there is an effect that power-saving is obtained.
[0026] Second, since the laser scanning range sensor 4 is attached not to the head part 1 which is moved by the three actuators, but to the body part 2 , there is an advantage that the laser scanning range sensor 4 can measure the distance from a surrounding obstacle or an object regardless of the posture of the head part 1 .
[0027] Third, since laser scanning range sensor 4 is not disposed in head part 1 , the degree of freedom of appearance design of the robot head part becomes large, so that natural appearance having an affinity to a human can be achieved.
[0028] Fourth, since the laser scanning range sensor 4 is disposed in a part corresponding to the neck part of the robot, there is an advantage that the laser scanning range sensor scanning plane 5 is rarely shielded during operation by the arms.
[0029] Further, in FIG. 2 , one laser scanning range sensor 4 is arranged to face forward. However, in order to scan the whole field, two may be arranged on the front and rear sides as shown in FIG. 3 , or two may be arranged on the right and left sides as shown in FIG. 4 .
[0030] FIG. 5 is a view showing the head part 1 from the pitch axial direction. In FIG. 5 , assuming that the distance between a top surface of the laser scanning range sensor 4 and the output shaft of the second head actuator 8 is l 1 , and the distance between the most distant point from the output shaft of the second head actuator 8 , among the second head link 9 , the third head actuator 10 , the third head link 11 and the face 12 of the robot which are integrally oscillated by the second head actuator 8 , and the output shaft of the second head actuator 8 is R 1 , the dimension of each element is decided to achieve l 1 >R 1 , so that even if the second head actuator 8 is oscillated at a predetermined angle, the components of the head part do not become an obstacle of the laser scanning range sensor scanning plane 5 .
[0031] FIG. 6 is a view showing the head part 1 from the roll axial direction rear, in which the neck link 3 is omitted to make it easy to see components of the head part 1 . In FIG. 6 , assuming that the distance between a top surface of the laser scanning range sensor 4 and the output shaft of the third head actuator 10 is l 2 , and the distance between the most distant point from the output shaft of the third head actuator 10 , between the third head link 11 and the face 12 of the robot which are integrally oscillated by the third head actuator 10 , and the output shaft of the third head actuator 10 is R 2 , the dimension of each component is decided to achieve l 2 >R 2 , so that even if the third head actuator 10 is oscillated at a predetermined angle, the components of the head part do not become an obstacle of the laser scanning range sensor scanning plane.
[0032] In the above embodiment, although the case where the head part 1 has three degrees of freedom is explained, the invention is not limited thereto, but also applicable to the case of one of the yaw axis, the roll axis and the pitch axis, or the combination of the two among those.
[0033] It should be further understood by those skilled in the art that although the foregoing description has been made on embodiments of the invention, the invention is not limited thereto and various changes and modifications may be made without departing from the spirit of the invention and the scope of the appended claims. | To provide a robot whose degree of freedom of design is not limited, and which has simple structure and further reduces load of an actuator of a neck part, the present invention provides a robot at least including a head part, a body part, and a neck link which connects the head part and the body part, wherein a surrounding object distance measurement means is provided adjacently to the neck link and in an upper portion of the body part between the head part and the body part, and a distance scanning field of the surrounding object distance measurement means is provided in parallel with a horizontal plane. | 1 |
FIELD OF THE INVENTION
[0001] This invention relates to flying toy apparatus, and particularly to flying toy apparatus capable of undergoing a hovering motion.
[0002] It is known to provide flying toy apparatus which is capable of undergoing hovering airborne motion in use thereby providing interest to both child and adult users. In order to stabilize hovering toy apparatus to prevent tilt or torque as a result of rotation of the toy itself or as a result of rotation of one or more propellers provided on the toy apparatus, stabilization systems or counter tilt/counter torque systems are normally required. One known stabilisation system uses a gyroscope to control the orientation or yaw of the toy. However, use of gyroscope stabilisation systems is expensive and complex and therefore undesirable. Other known systems use one or more counter-torque propellers to counteract the torque provided by a main propeller on the toy. However, use of additional propellers increases the cost and complexity of manufacturing the toy.
BACKGROUND OF THE INVENTION
[0003] U.S. Pat. No. 6,843,699 discloses rotating toy apparatus capable of undergoing hovering flight which utilizes a self-stabilisation mechanism. The toy includes a main rotor rotatably attached to a counter rotating main body. The main body includes a plurality of fixed blades attached between a central hub and an outer ring. As the main blade rotates, the torque reaction causes the main body to rotate in the opposite direction. Once the toy is flying the outer ring protects the main rotor and provides gyroscopic stability. Additionally, the blades provide a means for self-correcting tilts in the aircraft as they arise, so as to keep the aircraft horizontal in the air. If the toy tilts, it moves sideways in the direction of tilt. As a result, the blades on one side of the aircraft experience an increase in airspeed, whilst those on the opposite side experience a reduction. This creates a lift imbalance across the aircraft, that acts at 90 degrees to the direction of travel and this in turn creates a gyroscopic procession with a reaction force that is 90 degrees out of phase. The gyroscopic reaction thus acts in the opposite direction to the original tilt, thereby providing self stabilisation. Thus, the self stabilisation mechanism is dependent on the lift generated by the toy. A problem with this type of flying toy is that the effectiveness of the self stabilisation mechanism is dependent on the surrounding air flow and conditions.
[0004] It is an aim of the present invention to provide flying toy apparatus which overcomes the abovementioned problems.
[0005] It is a further aim of the present invention to provide a self stabilisation mechanism for flying toy apparatus.
[0006] It is a yet further aim of the present invention to provide a method of using flying toy apparatus.
BRIEF SUMMARY OF THE INVENTION
[0007] According to a first aspect of the present invention there is provided flying toy apparatus, said apparatus including a housing with drive means provided therein for driving rotation of rotary means associated with said housing, vane means being further associated with said housing and said vane means rotating in a counter direction to the rotation of said rotary means in use, and wherein said vane means are arranged substantially vertically in use.
[0008] The provision of the vertically arranged vane means on the toy apparatus allows the apparatus to self stabilise during flying as a result of utilising the downdraft created by the rotary means. The applicant is not aware of the downdraft of flying toy apparatus being used to create self stabilisation of the toy apparatus and this differs from the use of lift to self stabilise as used in the prior art.
[0009] Preferably the vane means (i.e. the height of the vane means) are arranged in a direction substantially parallel to the axis of rotation of said rotary means.
[0010] Preferably the rotary means includes at least two rotatable blades, such as propeller blades. The rotary means or blades are arranged so as to generate lift to allow the apparatus to become airborne. The blades typically rotate about a substantially central shaft and rotation of said shaft drives rotation of said blades in a required direction. The drive means drives rotation of said shaft and thus said blades.
[0011] Rotation of said rotary means causes said housing and said vane means associated with said housing to rotate in an opposite direction. Thus the drive means does not drive rotation of said vane means and said housing directly.
[0012] Preferably the vane means are offset from the centre of the apparatus, and particularly are offset from the axis of rotation of the rotatable shaft associated with said rotary means.
[0013] Preferably the vane means includes two or more vane members and in a preferred embodiment the vane means include four vane members.
[0014] Preferably each of the four vane members IS located at substantially 90 degrees to an adjacent vane member.
[0015] Preferably a first end or side surface adjacent said end of each of the vane members is joined to, associated with or integral with an external surface of the housing. The second or opposite end of each of the vane members can be a free end or can be associated with an outer joining member joining all the outer or second ends of the vane members or two or more of the vane members together.
[0016] Preferably the first or inner joined end or surface of each vane member is joined to, abuts or is near to a vertical or upright surface of an adjacent vane member and is a pre-determined spaced distance from the joined inner end or surface of said adjacent vane member. As such, in the embodiment in which four vane members are used, the joined inner ends of the vane members define a substantially square shaped centre or aperture between the vane members.
[0017] Preferably the free or outer end(s) of the vane members extend outwardly from the housing beyond the end(s) or free end(s) of the rotary means.
[0018] Preferably the rotary means are associated with a base or lower portion of the housing and the vane means are located above the rotary means (i.e. the vane means can be a spaced distance apart and associated with a top or upper section of the housing).
[0019] At least a portion of the lower surface of the vane means can be shaped so as to at least partially enclose the rotary means. For example a recess portion can be defined on the lower surface of the vane means to allow rotation of the rotary means within said recess portion. The recess portion is preferably defined on an inner portion of said lower surface.
[0020] The vane means and/or the rotary means can be made from any or any combination of suitable lightweight material, such as plastic, foam, wood, fabric and/or the like.
[0021] In one embodiment protruding means can be provided on or associated with one or more of the vane means and said protruding means protrudes outwardly of a side surface of said vane means. The protruding means is provided to increase the drag associated with one side of the vane means compared to an opposite side of the vane means, thereby providing a net tilt to the apparatus in the direction of the protruding means and creating a directional stimulus to the flying apparatus. The directional stimulus can be manipulated to allow a user to control the direction in which the flying apparatus moves in use.
[0022] Preferably the protruding means protrudes substantially transversally or at an acute angle relative to a side surface of the vane means.
[0023] Preferably the power to the drive means can be moved between “on” and “off” conditions or is pulsed during use to allow the directional stimulus generated by the protruding means to be used to control the direction of the toy apparatus. The burst of power and cutting of power or power pulses to the drive means can be provided each time the protruding means is in a particular orientation, thereby tilting the apparatus in a particular direction.
[0024] Preferably the power to the drive means is pulsed or switched between the “on” and “off” conditions automatically by the apparatus using directional means. For example, the directional means can include a directional light signal, such as for example a Light Emitting Diode (LED) beacon or signal. An LED provided on the apparatus or housing emits a light signal which is detected by user control means in use when the apparatus is in a particular orientation during each revolution. Detection of the light signal causes activation of an electrical signal in the user control means which controls the power supply to the drive means.
[0025] The user control means typically controls the power to the drive means remotely using communication means, such as radio waves and/ or waveforms at a different frequency, such as via microwave, infrared, light and/or the like.
[0026] The user control means is typically provided with actuation means, such as for example one or more control buttons, to allow control of the power and/or direction of the toy apparatus in use.
[0027] According to a second aspect of the present invention there is provided a method of self stabilising flying toy apparatus, said method including the steps of driving rotation of rotary means associated with a housing of said apparatus, said rotation causing vane means associated with said housing to rotate in a counter direction to the rotation of said rotary means in use, and wherein said vane means are arranged substantially vertically In use.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] Embodiments of the present invention will now be described with reference to the accompanying figures, wherein:
[0029] FIG. 1 is a plan view of flying toy apparatus according to an embodiment of the present invention.
[0030] FIG. 2 is a side view of the toy apparatus in FIG. 1 .
[0031] FIG. 3 is a plan view of the apparatus in FIG. 1 in use.
[0032] FIG. 4 is a plan view of a further embodiment of flying toy apparatus according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0033] Referring to the figures, there is illustrated toy apparatus 2 capable of undergoing hovering flight in use. The apparatus includes a housing 4 containing a motor for driving rotation of a shaft 6 extending below housing 4 .
[0034] Rotary means in the form of a pair of oppositely located propeller blades 8 are located at the base of rotatable shaft 6 . Blades 8 rotate about shaft 6 and, in use, shaft 6 and therefore the axis of rotation of blades 8 is substantially vertical. The blades 8 are typically located substantially horizontally or at an acute angle to the horizontal such that they provide the apparatus with lift on rotation of the same.
[0035] Vane means in the form of four vane members 10 are joined to the exterior surface of housing 4 and extend outwardly therefrom. The vane means are struck by the downdraft that is generated by the propeller blades when the toy flies, which allows self stabilisation of the toy as will be described in more detail below.
[0036] The vane members 10 are arranged substantially vertically, such that the height of the vane ‘h’ is substantially larger in size than the width ‘w’ thereof (i.e. the vane members are typically formed from sheet or plate like material). More particularly, each vane member 10 has a first inner end 12 and a second free outer end 14 . The inner ends 12 of the vane members 10 are offset from the centre of housing 4 , such that they define a substantially square central portion between said inner ends 12 . Thus, the inner end 12 of each vane member 10 is joined to the vertical surface 14 of an adjacent vane member a spaced distance's' from the inner end of said adjacent vane member. Each of the four vane members are arranged substantially perpendicularly with respect to an adjacent vane member.
[0037] Vane members 10 are arranged above blades 8 and the free ends 14 extend outwardly of the housing 4 beyond the free ends 16 of blades 8 . In the illustrated embodiment a recess portion 18 is defined on the lower surface of vane members 10 to allow rotation of blades 8 within said recess portion 18 .
[0038] In use of the toy 2 , the motor drives rotation of blades 8 in an anti-clockwise direction, thereby providing a torque reaction. This torque reaction acts on the housing 4 and vane members 10 causing the same to rotate in a clockwise direction as shown by arrows 20 . Rotation of blades 8 causes the toy 2 to become airborne and to hover and the provision of the vane means cause the toy 2 to be stabilised using its own downdraft represented by dotted line 22 .
[0039] As the front of apparatus 2 starts to move horizontally in a first direction, as shown by arrow 24 , the downdraft column on the rear side of the toy lags behind apparatus 2 as shown in FIG. 3 . As a result of the offset orientation of vane members 10 about housing 4 , vane member ‘A’ experiences a greater downdraft than opposite and parallel vane member ‘B’. This results in apparatus 2 tilting towards ‘A’ in a direction substantially perpendicular to the direction of forwards movement. This in turn creates a gyroscopic procession with a reaction force that is 90 degrees out of phase. The gyroscopic reaction thus acts in the opposite direction to the original tilt, as shown by arrow 26 . Thus, apparatus 2 is reacting gyroscopically with a tilting movement away from the direction of movement, thereby providing corrective feedback and self stabilising apparatus 2 as a result of the downdraft.
[0040] Thus, the self stabilisation mechanism used in the present invention provides a flying toy which is passively stable during flight in use. It does this by using propeller downdraft, which impinges on vane members provided on the toy to provide aerodynamic feedback to tilt itself to correct any horizontal movement of the toy.
[0041] With reference to FIG. 4 , a directional stimulus can be generated in the toy 2 as an optional feature to allow a user to control direction of flight of the toy in use. A protruding member in the form of a tab 28 can protrude outwardly from a single side surface 30 (i.e. a free surface facing inwardly of the apparatus and being substantially parallel to the axis of rotation of shaft 6 ) of a vane member 10 . Tab 28 generates an increased force from the downdraft experienced by the connecting vane member, thereby generating a net tilt in the direction of tab 28 as the toy 2 rotates. However, since the direction of tab 28 is constantly changing during rotation, the tab alone does not cause directional movement of the toy.
[0042] In order to cause directional movement, synchronised bursts of power are supplied to the motor each time the tab 28 is in a desired position. Corresponding breaks in the power supply each time the tab 28 is on the opposite side ensure that lift of the toy is preserved but the additional downdraft force on the tab side at the same place in each revolution of the vane member causes the apparatus to tilt in the desired direction.
[0043] The synchronised changes in the power supply to the motor can be achieved automatically using user control means provided with the toy 2 . The user control means of toy 2 typically includes a user held housing which communicates remotely with housing 4 of the toy using radio waves. An LED beacon provided on housing 4 is detected by a suitable sensor provided on the user control means during each revolution of housing 4 , each time the control means and the LED beacon become substantially aligned during rotation. Activation of the sensor generates an electrical signal in the user control means which allows the motor power changes to be synchronised to the aircraft's revolution. By choosing the appropriate phase delay between detecting the LED beacon and applying the motor power changes, the aircraft can be made to tilt and move in any desired direction. The user control means is preferably provided with push-buttons to allow selection of forwards, backwards, left or right movement. | Flying toy apparatus is provided including a housing with drive means provided therein for driving rotation of rotary means associated with said housing. Vane means are associated with said housing and said vane means rotate in a counter direction to the rotation of said rotary means in use. The vane means are arranged substantially vertically in use. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of copending International Application No. PCT/EP2004/014496, filed Dec. 20, 2004, which designated the United States and was not published in English, and is incorporated herein by reference in its entirety, and which claimed priority to German Patent Application No. 10 2004 007 185.3, filed Feb. 13, 2004.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the predictive coding of information signals, such as, for example, audio signals, and in particular to adaptive predictive coding.
2. Description of the Related Art
predictive coder—or transmitter—codes signals by predicting a current value of the signal to be coded by the previous or preceding values of the signal. In the case of linear prediction, this prediction or presumption is accomplished via the current value of the signal by a weighted sum of the previous values of the signal. The prediction weights or prediction coefficients are continuously adjusted or adapted to the signal so that the difference between the predicted signal and the actual signal is minimized in a predetermined manner. The prediction coefficients, for example, are optimized with regard to the square of the prediction error. The error criterion when optimizing the predictive coder or predictor, however, may also be selected to be something else. Instead of using the least square error criterion, the spectral flatness of the error signal, i.e. of the differences or residuals, may be minimized.
Only the differences between the predicted values and the actual values of the signal are transmitted to the decoder or receiver. These values are referred to as residuals or prediction errors. The actual signal value can be reconstructed in the receiver by using the same predictor and by adding the predicted value obtained in the same manner as in the coder to the prediction error having been transmitted by the coder.
The prediction weights for the prediction may be adapted to the signal with a predetermined speed. In the so-called least mean squares (LMS) algorithm, one parameter is used for this. The parameter must be adjusted in a manner acting as a trade-off between adaption speed and precision of the prediction coefficients. This parameter, which is sometimes also referred to as step-size parameter, thus determines how fast the prediction coefficients adapt to an optimum set of prediction coefficients, wherein a set of prediction coefficients not adjusted optimally results in the prediction to be less precise and thus the prediction errors to be greater, which in turn results in an increased bit rate for transmitting the signal since small values or small prediction errors or differences can be transmitted by fewer bits than greater ones.
A problem in predictive coding is that in the case of transmitting errors, i.e. if incorrectly transmitted prediction differences or errors occur, prediction will no longer be the same on the transmitter and receiver sides. Incorrect values will be reconstructed since, when a prediction error first occurs, it is added on the receiver side to the currently predicted value to obtain the decoded value of the signal. Subsequent values, too, are affected since the prediction on the receiver side is performed based on the signal values already decoded.
In order to obtain resynchronization or adjustment between transmitter and receiver, the predictors, i.e. the prediction algorithms, are reset to a certain state on the transmitter and receiver sides at predetermined times equal for both sides, a process also referred to as reset.
However, it is problematic that directly after such a reset the prediction coefficients are not adjusted to the signal at all. The adaption of these prediction coefficients, however, will always require some time starting from the reset times. This increases the mean prediction error resulting in an increased bit rate or reduced signal quality, such as, for example, due to distortions.
SUMMARY OF THE INVENTION
Consequently, it is an object of the present invention to provide a scheme for predictive coding of an information signal which, on the one hand, allows more sufficient robustness to errors in the difference value or residuals of the coded information signal and, on the other hand, allows a lower accompanying increase in the bit rate or decrease in signal quality.
In accordance with a first aspect, the present invention provides a method for predictively coding an information signal including a sequence of information values by means of an adaptive prediction algorithm the prediction coefficients of which may be initialized and which is controllable by a speed parameter to operate with a first adaption speed and a first adaption precision in the case that the speed parameter has a first value and to operate with a second, compared to the first one, lower adaption speed and a second, compared to the first one, higher adaption precision in the case that the speed parameter has a second value, having the steps of: A) initializing the prediction coefficients; B) controlling the adaptive prediction algorithm to set the speed parameter to the first value; C) coding successive information values of the information signal by means of the adaptive prediction algorithm with the speed parameter set to the first value as long as a predetermined duration after step B) has not expired to code a first part of the information signal; D) after expiry of the predetermined duration after step B), controlling the adaptive prediction algorithm to set the speed parameter to the second value; and E) coding information values of the information signal following the information values coded in step C) by means of the adaptive prediction algorithm with the speed parameter set to the second value to code a second part of the information signal following the first part.
In accordance with a second aspect, the present invention provides a device for predictively coding an information signal including a sequence of information values, having: means for performing an adaptive prediction algorithm the prediction coefficients of which may be initialized and which is controllable by a speed parameter to operate with a first adaption speed and a first adaption precision in the case that the speed parameter has a first value and to operate with a second, compared to the first one, lower adaption speed and a second, compared to the first one, higher adaption precision in the case that the speed parameter has a second value; and control means coupled to the means for performing the adaptive prediction algorithm and effective to cause: A) initialization of the prediction coefficients; B) control of the adaptive prediction algorithm to set the speed parameter to the first value; C) coding of successive information values of the information signal by means of the adaptive prediction algorithm with the speed parameter set to the first value as long as a predetermined duration after the control B) has not expired to code a first part of the information signal; D) after expiry of the predetermined duration after the control B), control of the adaptive prediction algorithm to set the speed parameter to the second value; and E) coding of information values of the information signal following the information values coded in the coding C) by means of the adaptive prediction algorithm with the speed parameter set to the second value to code a second part of the information signal following the first part.
In accordance with a third aspect, the present invention provides a method for decoding a predictively coded information signal including a sequence of difference values by means of an adaptive prediction algorithm the prediction coefficients of which may be initialized and which is controllable by a speed parameter to operate with a first adaption speed and a first adaption precision in the case that the speed parameter has a first value and to operate with a second, compared to the first one, lower adaption speed and a second, compared to the first one, higher adaption precision in the case that the speed parameter has a second value, having the steps of: F) initializing the prediction coefficients; G) controlling the adaptive prediction algorithm to set the speed parameter to the first value; H) decoding successive difference values of the predictively coded information signal by means of the adaptive prediction algorithm with the speed parameter set to the first value as long as a predetermined duration after step G) has not expired to decode a first part of the predictively coded information signal; I) after expiry of the predetermined duration after step G), controlling the adaptive prediction algorithm to set the speed parameter to the second value; and J) decoding difference values of the predictively coded information signal following the difference values decoded in step H) by means of the adaptive prediction algorithm with the speed parameter set to the second value to decode a second part of the predictively coded information signal.
In accordance with a fourth aspect, the present invention provides a device for decoding a predictively coded information signal including a sequence of difference values, having: means for performing an adaptive prediction algorithm the prediction coefficients of which may be initialized and which is controllable by a speed parameter to operate with a first adaption speed and a first adaption precision in the case that the speed parameter has a first value and to operate with a second, compared to the first one, lower adaption speed and a second, compared to the first one, higher adaption precision in the case that the speed parameter has a second value; and control means coupled to the means for performing the adaptive prediction algorithm and effective to cause: F) initialization of the prediction coefficients; G) control of the adaptive prediction algorithm to set the speed parameter to the first value; H) decoding of successive difference values of the predictively coded information signal by means of the adaptive prediction algorithm with the speed parameter set to the first value as long as a predetermined duration after the control G) has not expired to decode a first part of the predictively coded information signal; I) after expiry of the predetermined duration after the control G), control of the adaptive prediction algorithm to set the speed parameter to the second value; and J) decoding of difference values of the predictively coded information signal following the difference values decoded in the decoding H) by means of the adaptive prediction algorithm with the speed parameter set to the second value to decode a second part of the predictively coded information signal.
In accordance with a fifth aspect, the present invention provides a computer program having a program code for performing one of the above mentioned methods when the computer program runs on a computer.
The present invention is based on the finding that the, up to now, fixed setting of the speed parameter of the adaptive prediction algorithm acting as the basis of predictive coding has to be given up in favor of a variable setting of this parameter. If an adaptive prediction algorithm controllable by a speed coefficient is started from to operate with a first adaption speed and a first adaption precision and an accompanying first prediction precision in the case that the speed coefficient has a first value and to operate with a second, but compared to the first one, lower adaption speed and a second, compared to the first one, higher precision in the case that the speed parameter has a second value, the adaption durations occurring after the reset times where the prediction errors are at first increased due to the prediction coefficients having not yet been adapted can be decreased by at first setting the speed parameter to the first value and, after a while, to the second value. After setting the speed parameter again to the second value after a predetermined duration after the reset times, the prediction errors and thus the residuals to be transmitted are more optimized or smaller than would be possible with the first speed parameter value.
Put differently, the present invention is based on the finding that prediction errors can be minimized after reset times by altering the speed parameters, such as, for example, the step-size parameter of an LMS algorithm, for a certain duration after the reset times such that the speed of the adaption of the weights is increased for this duration—of course entailing reduced precision.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the present invention will be detailed subsequently referring to the appended drawings, in which:
FIG. 1 shows a block circuit diagram of a predictive coder according to an embodiment of the present invention;
FIG. 2 shows a block circuit diagram for illustrating the mode of functioning of the coder of FIG. 1 ;
FIG. 3 shows a block circuit diagram of a decoder corresponding to the coder of FIG. 1 according to an embodiment of the present invention;
FIG. 4 shows a flowchart for illustrating the mode of functioning of the decoder of FIG. 3 ;
FIG. 5 shows a block circuit diagram of the prediction means of FIGS. 1 and 3 according to an embodiment of the present invention;
FIG. 6 shows a block circuit diagram of the transversal filter of FIG. 5 according to an embodiment of the present invention;
FIG. 7 shows a block circuit diagram of the adaption controller of FIG. 5 according to an embodiment of the present invention; and
FIG. 8 shows a diagram for illustrating the behavior of the prediction means of FIG. 5 for two different fixedly set speed parameters.
DESCRIPTION OF PREFERRED EMBODIMENTS
Before discussing embodiments of the present invention in greater detail referring to the figures, it is pointed out that elements occurring in different figures are provided with same reference numerals and that a repeated description of these elements is omitted.
FIG. 1 shows a predictive coder 10 according to an embodiment of the present invention. The coder 10 includes an input 12 where it receives the information signal s to be coded and an output 14 where it outputs the coded information signal δ.
The information signal may be any signal, such as, for example, an audio signal, a video signal, a measuring signal or the like. The information signal s consists of a sequence of information values s(i), i∈|N, i.e. audio values, pixel values, measuring values or the like. The coded information signal δ includes, as will be discussed in greater detail below, a sequence of difference values or residuals δ(i), i∈|N, corresponding to the signal values s(i) in the manner described below.
Internally, the coder 10 includes prediction means 16 , a subtracter 18 and control means 20 . The prediction means 16 is connected to the input 12 in order to calculate, as will be discussed in greater detail below, a predicted value s′(n) from previous signal values s(m), m<n and m∈|N, for a current signal value s(n) and to output same to an output which in turn is connected to an inverting input of the subtracter 18 . A non-inverting input of the subtracter 18 is also connected to the input 12 to subtract the predicted value s′(m) from the actual signal value s(n)— or simply to calculate the difference of the two values— and to output the result at the output 14 as the difference value δ(n).
The prediction means 16 implements an adaptive prediction algorithm. In order to be able to perform the adaption, it receives the difference value δ(n)—also referred to as prediction error—at another input via a feedback path 22 . In addition, the prediction means 16 includes two control inputs connected to the control means 20 . By means of these control inputs, the control means 20 is able to initialize prediction coefficients or filter coefficients ω i of the prediction means 16 at certain times, as will be discussed in greater detail below, and to change a speed parameter of the prediction algorithm on which the prediction means 16 is based, which subsequently will be referred to by λ.
After the setup of the coder 10 of FIG. 1 has been described above referred to FIG. 1 , the mode of functioning thereof will be described subsequently referring to FIG. 2 , also referring to FIG. 1 , wherein subsequently it is assumed that it is just about to process an information signal s to be coded, i.e. signal values s(m), m<n, have already been coded.
In step 40 , the control means 20 at first initializes the prediction or filter coefficients ω i of the prediction means 16 . The initialization according to step 40 takes place at predetermined reset times. The reset times or, more precisely, the signal value numbers n where a reset according to step 40 has been performed may, for example, occur in fixed time intervals. The reset times may be reconstructed on the decoder side, for example by integrating information about same in the coded information signal δ or by standardizing the fixed time interval or the fixed number of signal values between same.
The coefficients ω i are set to any values which may, for example, be the same at any reset time, i.e. every time step 40 is executed. Preferably, the prediction coefficients are initialized in step 40 to values having been derived heuristically from typical representative information signals and having resulted, on average, i.e. over the representative set of information signals, such as, for example, a mixture of jazz, classical, rock etc. pieces of music, in an optimum set of prediction coefficients.
In step 42 , the control means 20 sets the speed parameter λ to a first value, wherein steps 40 and 42 are preferably executed essentially simultaneously to the reset times. As will become obvious subsequently, the setting of the speed parameter to the first value has the result that the prediction means 16 performs a quick adaption of the prediction coefficients ω i initialized in step 40 —of course entailing reduced adaption precision.
In step 44 , the prediction means 16 and the subtracter 18 cooperate as prediction means to code the information signal s and, in particular, the current signal value s(n) by predicting same using adaption of the prediction coefficients ω i . More precisely, step 44 includes several substeps, namely calculating a predicted value s′(n) for the current signal value s(n) by the prediction means 16 using previous signal values s(m), m<n, using the current prediction coefficients ω i , subtracting the value s′(n) predicted in this way from the actual signal value s(n) by the subtracter 18 , outputting the resulting difference value δ(n) at the output 14 as part of the coded information signal δ and adapting or adjusting the coefficients ω i by the prediction means 16 using the prediction error or difference value δ(n) it obtains via the feedback path 22 .
The prediction means 16 uses, for the adaption or adjustment of the prediction coefficients ω i , the speed parameter λ predetermined or set by the control means 20 which, as will be discussed in greater detail below referring to the embodiment of an LMS algorithm, determines how strongly the feedback prediction error δ(n) per adjustment iteration, here n, influences the adaption or update of the prediction coefficients ω i or how strongly the prediction coefficients ω i can change depending on the prediction error δ(n) per adaption iteration, i.e. per δ(n) fed back.
In step 46 , the control means 20 checks whether the speed parameter λ is to be altered or not. The determination of step 46 can be performed in different manners. Exemplarily, the control means 20 determines that a speed parameter change is to be performed when a predetermined duration has passed since the initialization or setting in step 40 and 42 , respectively. Alternatively, the control means 20 for determining evaluates, in step 46 , an adaption degree of the prediction means 16 , such as, for example, the approximation to an optimum set of coefficients ω i with correspondingly low means prediction errors, as will be discussed in greater detail below.
It is assumed that at first no speed parameter change is recognized in step 46 . In this case, the control means 20 checks in step 48 whether there is again a reset time, i.e. a time when for reasons of resynchronization the prediction coefficients are to be initialized again. At first, it is again assumed that there is no reset time. If there is no reset time, the prediction means 16 will continue coding the next signal value, as is indicated in FIG. 2 by “n→n+1”. In this manner, coding of the information signal s using adaption of the prediction coefficients ω i with the adaption speed, as is set by the speed parameter λ is continued until finally the control means 20 determines in step 46 when passing the loop 44 , 46 , 48 that a speed parameter change is to be performed. In this case, the control means 20 sets the speed parameter λ to a second value in step 50 . Setting the speed parameter λ to the second value results in the prediction means 16 , when passing the loop 44 - 48 , to perform, in step 44 , the adaption of the prediction coefficients ω i with a lower adaption speed from then on, however, with increased adaption precision so that in these passes following the speed parameter change time which refer to subsequent signal values of the information signal s, the resulting residuals δ(n) will become smaller, which in turn allows an increased compression rate when integrating the values δ(n) in the coded signal.
After having passed the loop 44 - 48 several times, the control means 20 will at some time recognize a reset time in step 48 , whereupon the functional flow starts over again at step 40 .
It is also to be pointed out that the manner in which the sequence of difference values δ(n) is integrated in the coded information signal δ has not been described in detail above. Although it would be possible to integrate the difference values δ(n) in the coded signal in a binary representation having a fixed bit length, it is, however, of more advantage to code the difference values δ(n) with a variable bit length, such as, for example, Huffman coding or arithmetic coding or another entropy coding. A bit rate advantage or an advantage of a smaller amount of bits required for coding the information signal s results in the coder 10 of FIG. 1 by the fact that after the reset times the speed parameter λ is temporarily at first set such that the adaption speed is great so that the prediction coefficients not having been adapted so far are adapted quickly, and then the speed parameter is set such that the adaption precision is greater so that subsequent prediction errors are smaller.
Now that the predictive coding according to an embodiment of the present invention has been described above, a decoder corresponding to the coder of FIG. 1 will be described subsequently in its setup and mode of functioning referring to FIGS. 3 and 4 according to an embodiment of the present invention. The decoder is indicated in FIG. 3 by the reference numeral 60 . It includes an input 62 for receiving the coded information signal δ consisting of the difference values or residuals δ(n), an output 64 for outputting the decoded information signal ŝ which corresponds to the original information signal s(n) except for rounding errors in the representation of the difference value δ(n) and correspondingly consists of a sequence of decoded signal values ŝ(n), prediction means 66 being identical to or having the same function as the one of the coder 10 of FIG. 1 , an adder 68 and control means 70 . It is pointed out that subsequently no differentiation is made between the decoded signal values ŝ(n) and the original signal values s(n), but both will be referred to as s(n), wherein the respective meaning of s(n) will become clear from the context.
An input of the prediction means 66 is connected to the output 64 to obtain signal values s(n) already decoded. From these signal values s(m), m<n, already decoded the prediction means 66 calculates a predicted value s′(n) for a current signal value s(n) to be decoded and outputs this predicted value to a first input of the adder 68 . A second input of the adder 68 is connected to the input 62 to add the predicted value s′(n) and the difference value δ(n) and to output the result or the sum to the output 64 as a part of the decoded signal ŝ and to the input of the prediction means 66 for predicting the next signal value.
Another input of the prediction means 66 is connected to the input 62 to obtain the difference value δ(n), wherein it then uses this value to adapt the current prediction coefficients ω i . Like in the prediction means 16 of FIG. 1 , the prediction coefficients ω i may be initialized by the control means 70 , like the speed parameter λ may be varied by the control means 70 .
The mode of functioning of the decoder 60 will be described subsequently referring at the same time to FIGS. 3 and 4 . In steps 90 and 92 corresponding to steps 40 and 42 , the control means 70 at first initializes the prediction coefficients ω i of the prediction means 66 and sets the speed parameter λ thereof to a first value corresponding to a higher adaption speed, but a reduced adaption precision.
In step 94 , the prediction means 66 decodes the coded information signal δ or the current difference value δ(n) by predicting the information signal using adaption of the prediction coefficients ω i . More precisely, step 94 includes several substeps. At first, the prediction means 66 knowing the signal values s(m) already decoded, m<n, predicts the current signal value to be determined therefrom to obtain the predicted value s′(n). Thus, the prediction means 66 uses the current prediction coefficients ω i . The current difference value δ(n) to be decoded is added by the adder 68 to the predicted value s′(n) to output the sum obtained in this way as a part of the decoded signal ŝ at the output 64 . However, the sum is also input in the prediction means 66 which will use this value s(n) in the next predictions. Additionally, the prediction means 66 uses the difference value δ(n) from the coded signal stream to adapt the current prediction coefficients ω i , the adaption speed and the adaption precision being predetermined by the currently set speed parameter λ. The prediction coefficients ω i are updated or adapted in this manner.
In step 96 corresponding to step 46 of FIG. 2 , the control means checks whether a speed parameter change is to take place. If this is not the case, in step 98 corresponding to step 48 the control means 70 will determine whether there is a reset time. If this is not the case, the loop of steps 94 - 98 will be passed again, this time for the next signal value s(n) or the next difference value δ(n), as is indicated in FIG. 4 by “n→n+1”.
If, however, there is a speed parameter alteration time in step 96 , in step 100 the control means 70 will set the speed parameter λ to a second value corresponding to a lower adaption speed but higher adaption precision, as has already been discussed with regard to coding.
As has been mentioned, it is ensured either by information in the coded information signal 62 or by standardization that the speed parameter changes and reset times occur at the same positions or between the same signal values or decoded signal values, namely on the transmitter side and the receiver side.
After a predictive coding scheme according to an embodiment of the present invention has been described in general referring to FIGS. 1-4 , a special embodiment of the prediction means 16 will be described now referring to FIGS. 5-7 , wherein in this embodiment the prediction means 16 operates according to an LMS adaption algorithm.
FIG. 5 shows the setup of the prediction means 16 according to the LMS algorithm embodiment. As has already been described referring to FIGS. 1 and 3 , the prediction means 16 includes an input 120 for signal values s(n), and input 122 for prediction errors or difference values δ(n), two control inputs 124 and 126 for initializing the coefficients ω i or setting the speed parameter δ and an output 128 for outputting the predicted value s′(n). Internally, the prediction means 16 includes a transversal filter 130 and an adaption controller 132 . The transversal filter 130 is connected between the input 120 and the output 128 . The adaption controller 132 is connected to the two control inputs 124 and 126 and additionally to the inputs 120 and 122 and also includes an output to pass on correction values δω i for the coefficients ω i to the transversal filter 130 .
The LMS algorithm implemented by the prediction means 16 —maybe in cooperation with the subtracter 18 (FIG. 1 )—is a linear adaptive filter algorithm which, put generally, consists of two basic processes:
1. A filter process including (a) calculating the output signal s′(n) of a linear filter responsive to an input signal s(n) by the transversal filter 130 and (b) generating an estimation error δ(n) by comparing the output signal s′(n) to a desired response s(n) by the subtracter 18 or obtaining the estimation error δ(n) from the coded information signal δ. 2. An adaptive process performed by the adaption controller 132 and comprising automatic adjustment of the filter coefficients ω i of the transversal filter 130 according to the estimation error δ(n).
The combination of these two cooperating processes results in a feedback loop, as has already been discussed referring to FIGS. 1-4 .
Details of the transversal filter 130 are illustrated in FIG. 6 . The transversal filter 130 receives at an input 140 the sequence of signal values s(n). The input 140 is followed by a series connection of m delay elements 142 so that the signal values s(n−1) . . . s(n-m) preceding the current signal value s(n) are present at connective nodes between the m delay elements 142 . Each of these signal values s(n−1) . . . s(n-m) or each of these connective nodes is applied to one of m weighting means 144 weighting or multiplying the respective applying signal value by a respective prediction weighting or a respective one of the filter coefficients ω i , i=1 . . . m. The weighting means 144 output their results to a respective one of a plurality of adders 146 connected in series so that the estimation value or predicted value s′(m) results to Σ i=0 m ω i ·s(n-i) at an output 148 of the transversal filter 130 from the sum of the last adder of the series connection.
In a broader sense, the estimation value s′(n) comes close to a value predicted according to the Wiener solution in a, in a broader sense, stationary surrounding when the number of iterations n reaches infinity.
The adaption controller 132 is shown in greater detail in FIG. 7 . The adaption controller 132 thus includes an input 160 where the sequence of difference values δ(n) is received. They are multiplied in weighting means 162 by the speed parameter λ, which is also referred to as step-size parameter. The result is fed to a plurality of m multiplication means 164 multiplying it by one of the signal values s(n−1) . . . s(n-m). The results of the multipliers 164 form correction values δω i . . . δω m . Consequently, the correction values δω i . . . δω m represent a scalar version of the internal product of the estimation error δ(n) and the vector from signal values s(n−1) . . . s(n-m). These correction values are added before the next filter step to the current coefficients ω i . . . ω m so that the next iteration step, i.e. for the signal value s(n+1), in the transversal filter 130 is performed with the new adapted coefficients ω i →ω i +δω i .
The scaling factor λ used in the adaption controller 132 and, as has already been mentioned, referred to as step-size parameter may be considered to be a positive quantity and should meet certain conditions relative to the spectral content of the information signal in order for the LMS algorithm realized by the means 16 of FIGS. 5-7 to be stable. Here, stability is to mean that with increasing n, i.e. when the adaption is performed with infinite duration, the means square error generated by the filter 130 reaches a constant value. An algorithm meeting this condition is referred to as mean square stable.
An alteration of the speed parameter λ causes an alteration in the adaption precision, i.e. in precision, since the coefficients ω i may be adjusted to an optimum set of coefficients. Maladjustment of the filter coefficients results in an increase in the mean square error or the energy in the difference values δ in the steady state n→∞. In particular, the feedback loop acting on the weights ω i acts like a low-pass filter, the determination duration constant of which is inversely proportional to the parameter λ. Consequently, the adaptive process is slowed down by setting the parameter λ to a small value, wherein the effects of this gradient noise on the weights ω i are largely filtered out. This has the reverse effect of reducing maladjustment.
FIG. 8 illustrates the influence of setting the parameter λ to different values λ 1 and λ 2 on the adaption behavior of the prediction means 16 of FIGS. 5-7 using a graph where the number of iterations n or the number of predictions and adaptions n is plotted along the x axis and the mean energy of the residual values δ(n) or the mean square error is plotted along the y axis. A continuous line refers to a speed parameter λ 1 . As can be seen, the adaption to a stationary state where the mean energy of the residual values basically remains constant requires a number n 1 of iterations. The energy of the residual values in the settled or quasi-stationary state is E 1 . A broken graph results for a greater speed parameter λ 2 , wherein, as may be seen, fewer iterations, namely n 2 , are required until the steady state is reached, wherein the steady state, however, entails a higher energy E 2 of the residual values. The settled state at E 1 or E 2 exhibits not only settling of the mean square error of the residual values or residuals to an asymptotic value, but also settling of the filter coefficients ω i to the optimum set of filter coefficients with a certain precision which in the case of λ 1 is higher and in the case of λ 2 is lower.
If, however, as has been described referring to FIGS. 1-4 , the speed parameter λ is at first set to the value λ 2 , an adaption of the coefficients ω i will at first be achieved quicker, wherein the change to λ 1 after a certain duration after the reset times then provides for the adaption precision for the following duration to be improved. All in all, a residual value energy graph allowing a higher compression than by one of the two parameter settings alone is achieved.
With regard to the above description of the figures, it is pointed out that the present invention is not limited to LMS algorithm implementations. Although, referring to FIGS. 5-8 , the present invention has been described in greater detail with regard to the LMS algorithm as an adaptive prediction algorithm, the present invention may also be applied in connection with other adaptive prediction algorithms where matching between adaption speed on the one hand and adaption precision on the other hand may be performed via a speed parameter. Since the adaption precision in turn influences the energy of the residual value, the speed parameter may always at first be set such that the adaption speed is great, whereupon it is then set to a value where the adaption speed is small, but the adaption precision is greater and thus the energy of the residual values is smaller. With such prediction algorithms, for example, there need not be a connection between the input 120 and the adaption controller 132 .
Additionally, it is pointed out that, instead of the fixed duration described above after the reset times for triggering the speed parameter change, triggering may also be performed depending on the adaption degree, such as, for example, triggering a speed parameter change when the coefficient corrections δω, such as, for example, a sum of the absolute values thereof, fall below a certain value, indicating an approximation to the quasi-stationary state, as is shown in FIG. 8 , to a certain approximation degree.
In particular, it is pointed out that depending on the circumstances the inventive scheme may also be implemented in software. The implementation may be on a digital storage medium, in particular on a disc or a CD having control signals which may be read out electronically which can cooperate with a programmable computer system such that the corresponding method will be executed. In general, the invention thus also is in a computer program product having a program code stored on a machine-readable carrier for performing the inventive method when the computer program product runs on a computer. Put differently, the invention may thus also be realized as a computer program having a program code for performing the method when the computer program runs on a computer.
While this invention has been described in terms of several preferred embodiments, there are alterations, permutations, and equivalents which fall within the scope of this invention. It should also be noted that there are many alternative ways of implementing the methods and compositions of the present invention. It is therefore intended that the following appended claims be interpreted as including all such alterations, permutations, and equivalents as fall within the true spirit and scope of the present invention. | If an adaptive prediction algorithm controllable by a speed coefficient is started from to operate with a first adaption speed and a first adaption precision and an accompanying first prediction precision in the case that the speed coefficient has a first value and to operate with a second, compared to the first one, lower adaption speed and a second, but compared to the first one, higher precision in the case that the speed parameter has a second value, the adaption durations occurring after the reset times where the prediction errors are at first increased due to the, not yet, adapted prediction coefficients may be decreased by at first setting the speed parameter to the first value and, after a while, to a second value. After the speed parameter has again been set to the second value after a predetermined duration after the reset times, the prediction errors and thus the residuals to be transmitted are more optimized or smaller than would be possible with the first speed parameter value. | 6 |
[0001] The present invention relates generally to measuring devices, and more particularly to a device for measuring and marking lines and points on steel I-beams.
BACKGROUND OF THE INVENTION
[0002] Steel I-beams are frequently used to build frameworks for large buildings and construction projects. The beams are connected together with bolts that must be positioned precisely given the large scale of the building. When the bolts are positioned even ⅛ of an inch off center, the stability of the project is endangered as the error is compounded over tens or hundreds of feet.
[0003] The measurement process is complicated by the fact that measurements are defined from the outside of the beam flange, while the hole itself is drilled in the beam web. Thus, it is impossible to use a standard tape measure, for example, to measure the required distance directly. Instead, a square is generally used in combination with a tape measure, to make the appropriate measurement.
[0004] More particularly describing the prior art as shown in FIGS. 1 - 4 , an I-beam 10 comprises a web 11 and two side flanges 12 . Typically, the intersection of web 11 and flanges 12 is rounded rather than square, defining radius 13 at the web/flange intersection.
[0005] To measure the locations of holes to be drilled in the beam, a tape measure 14 is first used to measure predetermined distances from one end of the beam. Marks 15 are used to indicate those distances. A square 17 is then used to mark lines 16 perpendicular to the flanges at those measured distances, generally by positioning the square an indicated in FIG. 3. Square 17 is then turned on its end and is used in conjunction with tape 14 to mark distances from the outside of the flange, as shown in FIG. 4. Square 17 and tape 14 generally cannot be used to measure that distance directly, due in large part to the curvature of the intersection between the web and the flange.
[0006] The precision of the foregoing method of measurement depends, in part, on whether the flanges are truly at right angles to the web. If one flange is bent in or out a little, the distance measured from the top of the flange will not be the same as the distance along the web. This leads to errors in marking holes, since the method uses distances from the top of the flange as a guide. In addition, the speed of the foregoing method is unsatisfactory since multiple tools and measurements are required for each point.
[0007] A need therefore exists for a method of measuring and marking lines and points on I-beams that doesn't require a combination of tools, and that is more exact than the method of the prior art. The present invention addresses that need.
SUMMARY OF THE INVENTION
[0008] Briefly describing one aspect of the present invention, there is provided a device for measuring and marking lines and points on a steel I-beam. The device comprises:
[0009] (a) a flange-contacting portion for contacting the flange of an I-beam to be marked, and for defining a line parallel to the flange;
[0010] (b) a measuring blade for measuring distances from the flange-contacting portion along the web of the beam; and
[0011] (c) a bridging portion for connecting the measuring blade to the flange-contacting portion by bridging the beam flange. The bridging portion connects the measuring blade to the flange-contacting portion in a way in which the measuring blade is perpendicular to a line parallel to the flange.
[0012] One object of the present invention is to provide a device for marking I-beams faster and more accurately that was possible using prior art tools and techniques.
[0013] Other objects and advantages will be apparent from the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] [0014]FIG. 1 is a perspective view of a steel I-beam.
[0015] [0015]FIG. 2 is a perspective view of the I-beam of FIG. 1, showing a tape measure being used to measure distances from one end of the beam.
[0016] [0016]FIG. 3 is a perspective view of the I-beam of FIG. 1, showing a square being used to mark perpendicular lines at the measured distances.
[0017] [0017]FIG. 4 is a perspective view of the I-beam of FIG. 1, showing a square and a tape measure being used to mark the locations of holes.
[0018] [0018]FIG. 5 is a perspective view of the I-beam of FIG. 1, showing the present invention being used to mark the locations of holes.
[0019] [0019]FIG. 6 is a perspective view of one embodiment of the measuring device of the present invention.
[0020] [0020]FIG. 7 is a close-up view of the measuring blade locking mechanism of the measuring device of FIG. 6.
[0021] [0021]FIG. 8 is a side view of the measuring device of FIG. 7.
[0022] [0022]FIG. 9 is a perspective view of another embodiment of the measuring device of the present invention.
[0023] [0023]FIG. 10 is a close-up view of the measuring blade locking mechanism of the measuring device of FIG. 9.
[0024] [0024]FIG. 11 is a side view of the measuring device of FIG. 10.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] For the purposes of promoting an understanding of the principles of the invention, reference will now be made to certain preferred embodiments and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
[0026] As indicated above, one aspect of the present invention relates to a device for measuring and marking lines and points in a steel I-beam. The preferred embodiment of the device comprises: (a) a flange-contacting portion for contacting the flange of an I-beam to be marked, and for defining a line parallel to the flange; (b) a measuring blade for measuring distances from the outside of the flange along the web of the beam; and (c) a bridging portion for connecting the measuring blade to the flange-contacting portion by bridging the beam flange. The bridging portion connects the measuring blade portion to the flange-contacting portion in a way in which the measuring blade is perpendicular to a line parallel to the flange.
[0027] Referring now to the drawings, FIG. 6 shows one preferred embodiment of the measuring device. Measuring device 20 comprises a flange-contacting portion 24 for contacting the flange of an I-beam to be marked, and for defining a line parallel to the flange. Measuring blade 21 is provided to measure distances from the flange-contacting portion along the web of the beam. Bridging portion 26 connects measuring blade 21 to flange-contacting portion 24 by bridging the beam flange, as shown in FIG. 5. A handle portion 27 may be provided to make the device easier to grip, and to provide additional structural stability to bridging portion 26 . Rib 25 may be included on flange-contacting portion 24 to aid in better defining a line perpendicular to the plans of the flange.
[0028] In one preferred embodiment the device includes a locking mechanism (alternatively referred to as a blade-gripping portion) to releasably hold measuring blade 21 . Preferred locking mechanism 30 includes two slotted gripping members 31 a and 31 b , which can be pulled together by tightening a nut 33 on a bolt 34 protruding from either of the gripping members. The sides (bottoms) of the slots are perpendicular to the line defined by flange-contacting portion 24 , so that measuring blade 21 is held perpendicular to the flange.
[0029] Preferably the dimensions of the slots in the slotted gripping members 31 a and 31 b are such that the “vertical” dimension is slightly larger than the thickness of the measuring blade to be used. With that dimension the blade is easily slid into and out of the slot, yet is held firmly by the gripping members. The “width” of the slots is such that when they are pulled together they contact the measuring blade before they contact each other, and thus grip and hold the measuring blade. Of course, the dimensions of the slots depend on the dimensions of the measuring blade to be used, but generally the slots will be about ⅛ inch high (defined by the vertical wall of the slot), about ⅜ inch wide (defined by the longest horizontal wall of the slot), and about 1 inch deep to accommodate a standard 1-inch wide measuring blade. In the most preferred embodiments the slotted gripping members have a slot {fraction (1/16)} to 1 / 4 inch high, ¼ to 1 inch wide, and ½ to 2 inches deep, although larger or smaller sizes could be made to accommodate larger or smaller measuring blades.
[0030] It is important that the gripping members hold the measuring blade perpendicular to the I-beam flange. Accordingly, measuring device 20 has a flange-contacting portion 24 that contacts the flange and defines a line (or a plane) generally parallel to the plane of the flange. Gripping members 31 a and 31 b are then positioned so that the slots therein are perpendicular to that line (or plane). When measuring blade is gripped by the gripping members, the blade is also perpendicular to the beam flange. In one preferred embodiment, flange-contacting portion 24 is equipped with a rib 25 to help better define a line parallel to the plane of the flange at the location being measured, i.e., at the outside of the flange opposite the center of the web.
[0031] In another embodiment the blade is held by a locking mechanism 37 comprising a housing 38 and a locking screw 39 . Here too, the locking mechanism releasably holds the blade so that the blade is held in position perpendicular to the flange-contacting portion of the device.
[0032] Bridging portion 26 connects the blade-gripping portion to the flange-contacting portion. Preferably the bridging portion bridges the flange so that the device only contacts the flange at the flange-contacting portion opposite the web. The height of the bridging portion therefore depends on the height of the flange, but is typically about 7-10 inches. A handle portion 27 may be incorporated into bridging portion 26 to make the device easier to grip, and to lend additional structural support to the device.
[0033] The most preferred embodiments of the device include a measuring blade, although that piece can be provided by the end user if desired. Measuring blade 21 is marked with visual indicators of distance, most preferably distances from the outside of the flange opposite the web. Measuring blades such as common metal rulers can be used, with the blade preferably being cut so as to indicate the distance from the outer surface of the flange when the blade is held securely in the device. Generally, the blade is shortened by the distance from the flange-contacting portion to the nearest end of the blade, so that correct measurements are indicated.
[0034] It is to be appreciated that the device should be made of a material that is strong enough to withstand use on a construction site without becoming bent or broken. The strength of the bridging portion is of particular concern, since the distance between the flange-contacting portion and the end of the measuring blade should be constant over time. To assure proper measurements, the device should be calibrated regularly, and the blade can be lengthened or shortened if necessary.
[0035] To use the inventive device, the device is positioned over an I-beam flange so that the measuring blade rests on the beam web and the flange-contacting portion is pushed up against the outside of the flange, as shown generally in FIG. 5. The heights of the two arms of the bridging portion are such that the flange-contacting portion (most preferably the rib) contacts the flange opposite the center of the web when the measuring blade rests on the web surface. The device can then be used to mark points at specific distances from the outside of the flange, and to mark several points along a line perpendicular to the plane of the flange.
[0036] While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. | A device for measuring and marking lines and points on a steel I-beam includes a rib for contacting the outside of an I-beam flange along a line opposite the center of the beam web, a measuring blade that rests on the beam web and measures distances from the outside of the flange, and a bridge for connecting the measuring blade to the rib in a way in which the measuring blade is held perpendicular to the flange. The device marks I-beams faster and more accurately that was possible using prior art tools and techniques. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
This application takes priority from U.S. patent application Ser. No. 60/093,714 filed Jul. 22, 1998.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to oil well completion strings and more particularly to a hydrostatically-balanced open hole gravel pack system wherein hydrostatic pressure is maintained on the formation throughout the gravel packing operations.
2. Description of the Art
To obtain hydrocarbons from earth's subsurface formations, wellbores or boreholes are drilled into hydrocarbon-bearing formations or producing zones. After drilling a wellbore to the desired depth, a completion string containing various completion and production devices is installed in the wellbore to produce the hydrocarbons from the production zone to the surface. In one method, a fluid flow restriction device, usually containing one or more serially connected screens, is placed adjacent the production zone. Gravel is then packed in the space or annulus between the wellbore and the screen. No casing is installed between the screens and the wellbore. Such completions are called “open hole” completions and the systems used to gravel pack are called open hole gravel pack systems.
In commercially used open hole gravel packing system a completion string is frequently utilized for gravel packing. The completion string usually includes a screen near its bottom (or the downhole end), at least one packer or packing element above the screens, and a mechanism above the packer that allows gravel slurry to flow it from the surface to the annulus between the screens and the wellbore, and the clean fluid to return from the completion string to the surface. To gravel pack the annulus between the formation and the completion string, packer is set to form a seal between the completion string and the wellbore, the packer prevents the hydrostatic pressure from being applied to the formation, which prevents, for a period of time, maintaining the hydrostatic pressure above the formation pressure (the “overbalanced condition” or “overburdened condition”) during the gravel pack operation. Thus, the formation pressure can exceed the hydrostatic pressure, which can cause hole damage or well collapse and damage to the filter cake.
A substantial number of currently drilled wellbores are highly deviated or horizontal. The horizontal wellbores are extremely susceptible to damage if the overbalanced conditions are not maintained throughout the gravel pack operations or during any other completion operation. Maintaining the wellbore under overbalanced condition throughout the gravel packing, especially in highly deviated and horizontal wells is very desirable. The present invention provides a gravel pack system and method which maintains the pressure on the formation above the formation pressure throughout the gravel packing operation. The present system also is simpler and easier to use, thereby reducing the overall completion or gravel pack operations time and cost.
SUMMARY OF THE INVENTION
The present invention provides apparatus and method for gravel packing open holes wherein hydrostatic pressure on the formation is maintained above the formation pressure throughout the gravel pack process. In one embodiment, the gravel pack apparatus includes a completion string which contains a fluid flow restriction device, a crossover device uphole of the fluid flow restriction device and a packer above and below the crossover device. The completion string is conveyed in the wellbore to position the flow restriction device adjacent the producing formation while maintaining the wellbore under overburdened conditions. The upper packer and the crossover device are set while maintaining the wellbore under overburdened condition. This allows the gravel fluid to pass to the annulus and return through the completion string. The returning fluid crosses over to the annulus above the upper packer. After gravel packing, the lower packer is set. The portion of the completion string above the lower packer, which includes the crossover device and the upper packer are retrieved from the wellbore, thus leaving the fluid flow restriction device and the lower packer in the wellbore. In this particular embodiment, setting the lower packer after the gravel packing process has been completed enables maintaining the hydrostatic pressure on the formation throughout the gravel packing process.
Examples of the more important feature of the invention have been summarized rather broadly in order that the detailed description thereof that follows may be better understood, and in order that the contributions to the art may be appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject of the claims appended hereto.
BRIEF DESCRIPTION OF THE DRAWINGS
For detailed understanding of the present invention, reference should be made to the following detailed description of the preferred embodiment, taken in conjunction with the accompanying drawings, in which like elements have been given like numerals:
FIGS. 1A-1D show a schematic diagram of a gravel pack string for placement in the wellbore and the wellbore fluid flow path to hydrostatically balance the formation.
FIGS. 2A-2D show a schematic diagram of the gravel pack string with the upper or service packer set and the fluid flow path which enables maintaining the hydrostatic pressure on the formation.
FIGS. 3A-3D show the gravel pack system of FIGS. 1A-1D with the service packer set for a reverse circulation flow path.
FIGS. 4A-4D show the gravel pack system of FIGS. 1A-1D after the Run-in tool and the service packers have been removed, leaving the screen and the liner packer in the wellbore.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1A-1D, 2 A- 2 D, 3 A- 3 D, and 4 A- 4 D show a gravel pack system 10 according to one embodiment of the present invention in various stages of gravel pack operations.
Referring to FIGS. 1A-1D, the system 10 includes a fluid flow restriction device 100 having a number of serially disposed screen assemblies 110 a - 110 c . The fluid flow restriction device 100 terminates at the bottom end of the string 10 with a plug 112 and a casing joint 114 . Each screen assembly, such as assembly 110 a , includes an outer shroud 120 and an inner sand screen 122 . The shroud 120 protects the internal parts of the screen assembly 110 a from direct impact of the production fluid 202 , while the screen 122 prevents gravel, sand and other small solid particles from penetrating into the flow restriction device inside 116 . The screen 122 , however, maintains the string inside 116 in fluid communication with the formation 200 . Any fluid 40 supplied from the surface into the opening 116 at a pressure greater than the pressure of the formation 200 travels downhole to the plug 112 . This fluid then returns uphole (return fluid 42 ) via an opening 124 at the casing joint 114 . The returning fluid 42 passes through the screen assemblies 110 a - 110 c (as shown by arrows 43 ) to the annulus 204 between the flow restriction device 100 and the wellbore 201 and travels uphole via the annulus 204 , as shown by arrows 44 . The purpose of the flow restriction device 100 is to prevent solids present in the production fluid 202 to pass into the opening 116 of the string 10 . It also prevents passage of any gravel though the screens 122 into the completion string inside 116 that is supplied to the annulus 204 from the surface.
A liner packer 150 is disposed uphill of (above) the flow restriction device 100 . A casing nipple 160 and a knock-out isolation valve 165 are serially coupled between the liner packer 150 and the flow restriction device 100 . A running tool 140 in the liner packer 150 is used to convey the liner packer 150 and the flow restriction device 100 into the wellbore 201 . An end 140 a of the running tool couples a swivel sub 162 in the casing nipple 160 . The swivel sub 162 allows the tool portion above or uphole of the swivel sub 162 to rotate while maintaining stationary the tool portion 163 below the swivel sub.
The liner packer 150 includes setting slips 151 and one or more packing elements 152 . A liner packer setting dog (not shown) when moved downhole, causes the packer elements 152 to set, i.e., extend outward to the wellbore inside walls. Seals 144 in a junk bonnet 145 at the top of the liner packer 150 allow a polished stinger 143 to maintain seal. In the above-described configuration, the running tool 140 is attached to the section of the completion string that includes the liner packer assembly 150 and the flow restriction device 100 (referred to herein as the “bottom hole assembly” or the “BHA”). This allows an operator to rotate and release the running tool 140 from the bottom hole assembly to pull out the upper section of the completion string 100 out of the wellbore 201 , leaving behind the BHA in the wellbore 201 .
A crossover port assembly or device 170 is coupled uphole of the liner packer assembly 150 through the stringer 143 . The crossover port assembly 170 includes a port 172 which is initially closed off by a sleeve 174 . When the port 172 is closed, as shown in FIG. 1C, fluid supplied under pressure from the surface flows down to an opening 176 in the crossover port assembly 170 and continues to flow through the liner packer assembly 150 and the flow restriction device 100 as show by arrows 40 . When the sleeve 174 is moved downward, i.e., downhole, the port 172 opens. If the flow path below the port 172 is blocked, then any fluid supplied to the completion string 10 above the port 172 will flow through the port 172 and into the annulus 204 and eventually return uphole through the central bore 116 along the completion string 10 length. In the particular embodiment of FIGS. 1A-1D, a gravel pack kit 185 and a service packer 180 are disposed uphole of the crossover device 170 .
The service packer 180 can be hydraulically set to block or restrict fluid flow through the annulus 204 uphole of the crossover device 170 . The gravel pack kit 185 includes a port 186 that allows the fluid to flow from a reverse fluid flow path 179 in the service packer 180 to the annulus 204 above the service packer 180 as more fully explained below. The service packer 180 includes slips 181 and a plurality of packing elements 183 . Thus, the gravel pack system or completion string 10 shown in FIGS. 1A-1D includes in a substantially serial relation a flow restriction device 100 , a liner packer 150 above the flow restriction device 100 , a crossover port assembly tool 170 , and a service packer 180 uphole of the crossover device 170 . The gravel packing around the flow restriction device 100 while maintaining the hydrostatic pressure above the formation pressure will now be described while referring to FIGS. 1-4.
The completion string 10 shown in FIGS. 1A-1D is conveyed into the wellbore 201 to a desired depth to position the flow restriction device 100 adjacent the producing formation 200 . A wellbore fluid 40 is pumped from a source thereof at the surface (not shown) into the completion string 10 . The fluid flows through the string 10 as shown by the arrows 40 and returns to the surface via the annulus 204 as shown by the arrows 43 . The fluid in the wellbore maintains the hydrostatic pressure over the formation 200 , i.e., maintains the wellbore under overburdened condition.
Once the string 10 is correctly positioned in the wellbore 201 , the running tool 140 is released (or disengaged) from the liner packer 150 by rotating the pipe or the work string (attached above the string 10 ), which rotates the string 10 above the swivel sub 162 . The work string is then moved up or uphole, which causes the slips 181 of the service packer 180 to move over members 182 , which sets the packer elements 183 of the service packer 180 (See FIGS. 2 A- 2 D). Setting of the service packer 180 blocks any fluid flow through the annulus 204 around the packer elements 183 . Since the fluid in the string 10 remains in fluid communication with the formation 200 , it maintains the hydrostatic pressure on the formation 200 .
After setting the service packer 180 , a ball 190 is dropped into the completion string 10 , which moves the sleeve 174 , thus opening the port 172 . The ball 190 seats in position in the crossover assembly 170 and prevents fluid flow through the crossover assembly 170 past the ball 190 . The movement of sleeve 174 also opens a reverse fluid flow path 177 in the crossover port assembly which is further in fluid communication with fluid path 179 in the service packer assembly 180 . Thus, activating or setting the crossover assembly 170 causes any fluid supplied from the surface to flow through the string 10 to the port 172 and then over to the annulus 204 via the port 172 . The fluid then flows downhole through the annulus 204 and passes through the screens 110 a - 110 c and then into the string opening 116 as shown by arrows 50 (FIGS. 2 A- 2 D). The fluid then flows uphole through the opening 116 in the flow restriction assembly 100 and then through openings 117 and 118 respectively in the liner packer 150 and the crossover tool 170 . The fluid then crosses over to the line or opening 179 through the service packer via crossover opening 177 . The fluid from line 179 passes into the annulus 204 above the packer 180 via port 186 in the crossover kit 195 . The downhole fluid flow path after the setting of the crossover assembly 170 is depicted by arrows 50 , while the uphole fluid flow path of the returning fluid is shown by arrows 52 . Thus, during the setting of the crossover assembly 170 to establish fluid flow below the service packer via the annulus 204 , the fluid in the wellbore 201 remains in fluid communication with the formation 200 , thereby maintaining the hydrostatic pressure on the formation 200 .
Still referring to FIGS. 2A-2D, once the service packer 180 has been set, fluid 188 with gravel or sand 189 (also known in the art as “propant”) is pumped into the string 10 from a source at the surface (not shown). The gravel fluid 188 flows to the annulus 204 around the flow restriction device 100 . The flow restriction device 100 prevents the gravel 189 from entering into the tool inside 116 . The gravel 189 deposits or settles in the annulus 204 while the filtered fluid enters the opening 116 and travels uphole as shown by arrows 52 . The supply of the gravel fluid is continued until the annulus 204 around the flow restriction device 100 is packed with the gravel 189 .
Referring to FIGS. 3A-3D, after the desired amount of gravel 189 has been packed around the flow restriction device 100 , the work string is picked-up, which opens bypass 220 in the service packer 180 . Clean fluid 222 is pumped downhole, along the annulus fluid flow path shown by arrows 55 and returns uphole though the flow opening 224 via the port 172 . This reverse circulation removes any excess sand or gravel from the work string.
The junk bonnet 144 is then sheared off. The packer setting dog sub 154 is then removed. The liner packer 150 is then set and the string above the bottom hole assembly is pulled out of the wellbore 201 . The work string, the gravel pack kit 185 , the service packer 180 and the crossover device 170 are replaced by production tubing 230 (FIGS. 4 B- 4 D).
It should be noted that in the particular method of this invention described herein, the liner packer 150 is set after the gravel pack operation has been completed, which allows maintaining the hydrostatic pressure on the formation throughout the gravel pack operations, thus, maintaining overbalanced or over burdened condition during all stages of the gravel packing operations. This system 10 also requires no gravel pack ports in the hook-up. Full inner dimensions or diameter is available throughout the operations. This method causes no swabbing or disturbance of the open hole filter cake.
The gravel pack system described herein above may utilize an combination of devices or any configuration that allows maintaining the hydrostatic pressure on the formation throughout the completion operations, such as gravel pack operations described above. The devices, such as packers, run-in tools, flow restriction devices described herein above are known in the oil field and thus are not described in great detail.
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 variations within the scope and spirit of the appended claims be embraced by the foregoing disclosure. | The present invention provides apparatus and method for gravel packing open holes wherein hydrostatic pressure is maintained above the formation pressure (“overburdened condition”) throughout the gravel pack process. The apparatus includes a completion string which contains a flow restriction device, a crossover device and a packer each above and below the crossover device. The string is set in the wellbore with the flow restriction device adjacent the producing formation. The upper packer and the crossover device are set, which allows the gravel fluid to pass to the annulus, and return through the string. After gravel packing, the lower packer is set. The crossover device and the upper packer are retrieved from the wellbore leaving the flow restriction device and the lower packer in the wellbore. The system maintains the wellbore under overburdened condition throughout the gravel packing process. | 4 |
TECHNICAL FIELD OF THE INVENTION
[0001] The present invention relates to a method for production of transgenic cotton plants. The invention particularly relates to a Squamosa Promoter Binding like Transcription Factor 5 (SPL5) involved in the modulation of boll density (boll number and size) and lint percentage in cotton. Methods and means are provided to alter fiber quality and quantity by increasing or decreasing the SPL5 level thereby improving the cotton yield and increasing the breeding of such plants.
BACKGROUND AND PRIOR ART OF THE INVENTION
[0002] Three main factors namely global factors, population growth and the adoption of crops for biofuels create the necessity to develop novel approaches to increase crop yield. Crop productivity and yield enhancement in recent years are being achieved by genotype improvement through classical breeding, use of nitrogen fertilizer and pesticide, right agronomic way. Due to rapid population growth, income growth in developing countries, limited availability of land and climate change, achieving sustainable food security will require technological advances in agronomic practices, breeding and agricultural biotechnology (Dyson 1999, PNAS, 96(11): 5929-5936;Pinstrup-Anderson et al 1999, World Food Prospects: Critical issues for the Early Twenty-First Century, in 2020 Vision Food Policy Report). Cotton contributes natural fiber for the worldwide textile industry; therefore, dissecting its biological properties is a very important scientific objective. Although it is not easy to improve both yield and fiber quality concurrently; the yield of cotton fibers, usually known as cotton lint, is usually negatively associated with fiber quality. Aim to be achieved include increased cotton boll density, lint percentage, fiber length and strength. Presently cotton fiber quality can be improved by three types. First is by cross breeding but this method need much more time. Second is the use of fatty acids and plant hormones. Plant hormone such as Auxin or gibberellins has a promoting effect on the fiber elongation in ovule cultures {Beasley and Ting (Amer. J. Bot., 60(2): 130-139(1973), Baert et al., 1975} whereas kinetin and abscisic acid have an inhibitory effect. U.S. Pat. No. 5,880,110 produces cotton fibers with improved quality by treatment with brassinosteroids. Yong-Mei Qin et al., 2007 have reported that saturated very-long-chain fatty acids (VLCFAs; C20:0 to C30:0) exogenously applied in ovule culture medium significantly promoted cotton (Cotton) fiber cell elongation. The third one is by doing genetic manipulation. In recent years genetic manipulations have been made successful variety improvement in plants such as rice, tomato, maize etc. Therefore if a gene related with fiber development is transformed into cotton and overexpressed, it may play crucial role in the improvement of quality or yield of cotton fiber. At present, however, only the few studies have been made on cotton plants to improve the characteristics or yields of fiber such as by introduction of a BT toxin ( Bacillus thuringiensis ) gene into cotton to improve insect resistance, to improve herbicide (Glyphosate) resistance by introduction of 5-enol-pyruvilsshikimic acid 3-phosphate synthetase gene in cotton. There are few reports related to the method for genetically engineering a fiber producing plant and the identification of cDNA clones useful for identifying fiber genes in cotton. U.S. Pat. No. 5,597,718. Complete ORF sequence from these isolated genes is used in sense or antisense orientation to modulate the transgenic fiber producing plants. Suppression of sucrose synthase gene expression in cotton leads to reduced cell fiber length and smaller and fewer fiber cells (Yong-Ling Ruan et al, Plant Cell 15:952-964, 2003)
[0003] Identification and manipulation of specific genes in cotton that play a significant role in determining yield could provide a path to obtain substantial yield increase in a relatively short time.
[0004] SPL5 is a plant specific transcription factor which belongs to the SBP superfamily. Members of this superfamily share a highly conserved DNA binding SBP domain and are involved in various function such as flowering, early stages of microsporogenesis and megasporogenesis, development of normal plant architecture maize kernel development, tomato fruit ripeness, and shoot maturation in Arabidopsis (Cordon et. al Plant J. 1997, 12, 367-77; Unte et al, Plant Cell 2003, 15, 1009-1019; Wang et al, Nature 2005, 436, 714-719; Manning et al, Nat. Genet. 2006, 38, 948-952).
[0005] SPLs are among the transcription factors subjected to microRNA (miRNA) regulation. miR156 negatively regulates SPL gene family in Arabidopsis. miRNA originate from distinct loci within a plant's genome and are short non coding RNAs (20-24 nucleotide long) whose function is to repress the expression of defined target genes (Rhoades et al., Cell 110:513-520 110:513-520, 2002; Bonnet et al., Proc. Natl. Sci. USA, 101:11511-11516, 2004;Reinhart et al., Genes Dev. 16:1616-1626, 2002). miRNAs are produced from longer precursor molecules by a Dicer-like (DCL) ribonuclease and get incorporated into ribonucleoprotein silencing complexes that effect repression of target mRNAs via base pairing of the small RNA and its target mRNA (Chen, Science 303:2022-2025, 2004; Bao et al, Dev. Cell. 7:653-662, 2004). A number of researches have supported that SPL mRNAs are repressed by miR156 and this repression produces late flowering phenotype (Wu et al, Cell 138,750-759, 2009; Yamaguchi et al, Developmental Cell 17, 268-278, 2009).
Limitations in Prior Art
[0006] Presently no gene has been identified which causes significant increase in the boll number, size and increase in lint yield in cotton. Hence there was need to identify cotton boll density specific gene. In this present invention, we have identified a gene from Cotton which causes increase in number of cotton boll. The gene also causes significant increase in boll size and increased lint percentage. The prior art lacks identification of gene responsible for above said traits in cotton.
OBJECTIVE OF THE INVENTION
[0007] The main objective of the invention is to provide a method for production of transgenic cotton plants wherein the plant has increased number, size and lint yield.
SUMMARY OF THE INVENTION
[0008] Accordingly, the present invention provides a method for production of transgenic cotton plants.
[0009] The present invention provides plants comprising a plant growth and/or development nucleic acid/gene of the present invention, as well as compositions and methods for producing such plants.
[0010] In a further embodiment, the full-length plant growth and/or development nucleic acid/gene is operatively associated with a cauliflower mosaic virus 35S constitutive promoter (CaMV35S) and optionally with a polyA sequence, wherein the plants of the present invention have an increase in boll number, boll size and lint percentage as compared with a wild-type plant which does not comprise the nucleic acid/gene.
[0011] In another embodiment, truncated plant growth and/or development nucleic acid/gene is operatively associated with a constitutive promoter and intron with a optionally polyA sequence, wherein the plants have a decrease in boll number, boll size and lint percentage as compared with a wild type plant which does not comprise the nucleic acid/gene.
[0012] In one embodiment, the resultant increase in boll number, size and lint percentage leads to increased yield.
[0013] The present invention also provides transformed cells, tissue cultures and/or plant parts comprising the modified plant growth and/or development nucleic acid/gene of the present invention. The transformed cell, tissue culture or plant part can be derived from regenerable cells from embryos, protoplasts, meristemetic cells, callus, pollen, leaves, anthers, stems, petioles, roots, root tips, fruits, seeds, flowers, cotyledons, or hypocotyls.
[0014] In one embodiment, the modified plant growth and/or development nucleic acid/gene has no miRNA binding site.
[0015] In one embodiments, the modified plant growth and/or development nucleic acid/gene is operatively associated with a constitutive promoter and optionally a polyA sequence, wherein the transformed cell, tissue culture or plant part can give rise to a transgenic plant demonstrating an increase in boll number, size and lint percentage as compared with a wild-type plant or a plant which comprise the silenced plant growth and/or development nucleic acid/gene.
[0016] In some further embodiments, the SPL5 gene is from cotton.
[0017] The present methods and compositions increase boll number, size and lint percentage in plants. In some embodiments, the present methods and compositions relate to the use of a modified growth and/or development regulatory nucleic acid/gene that is over-expressed in a plant. In particular, the present methods and compositions relate to the use of a miRNA-resistant growth and/or development regulatory nucleic acid/gene comprising under the control of an appropriate constitutive promoter. In some embodiments, the plant is a transgenic plant, and the growth and/or development regulatory gene is a transgene in the transgenic plant. Over expression of the modified gene in a plant provides for increased boll number, size and lint percentage in the transgenic plant when compared with the wild-type plant; whereas, knockdown expression of growth and/or development regulatory gene produced decreased boll number, size and lint percentage in the transgenic plant when compared with the wild-type plant.
[0018] The present disclosure also provides methods for selecting for a nucleic acid/gene that increases plant yield when functionally associated with a constitutive promoter; wherein the methods comprise constructing an expression vector comprising a nucleic acid/gene associated with plant growth and/or development having no miRNA binding site, transfecting a plant cell with the expression vector to form a transgenic plant; growing the transgenic plant and selecting those transgenic plants that have an increased yield.
[0019] In another embodiment the invention provides a method for production of transgenic cotton plants useful to obtain increase in yield of boll number and size comprising steps of:
a) Providing cotton genomic DNA and cDNA having the SPL5 gene of sequence I.D. 1; b) Amplifying SPL5 gene from the DNA obtained in step (a) using primer sequence of sequence I.D. 3 and 4. c) Cloning the amplified gene obtained in step (b) into a suitable expression vector operably linked to promoter selected from but not restricted to FBP7, Actin, TA29 and CaMV35S d) Transforming the vector into cotton plant using Agrobacterium mediated transformation to obtain transgenic cotton plant having increase in yield of boll number and size.
[0024] In yet another embodiment the invention provides a recombinant construct useful for increasing the yield of boll number and size in cotton of transgenic cotton plant comprising a plant growth & development regulator SPL5 gene of sequence I.D.1 operably linked to promoter selected from but not restricted to FBP7, Actin, TA29 and CaMV35S for transforming cotton plants.
[0025] In yet another embodiment the invention provides a process of cotton transformation for producing transgenic plants containing gene of sequence I.D. 1 comprising steps;
A) Providing the construct containing Seq Id no. 1; B) Transforming Agrobacterium strain GV3101 with the construct obtained in step (A); C) Transforming the cotton plant with Agrobacterium obtained in step (B); D) Regenerating transformed cotton plants obtained in step (C).
[0030] In yet another embodiment the invention provides a construct for transformation of cotton plants, comprising nucleotide having seq ID no. 1 encoding a polypeptide of seq. I.D. no. 2.
[0031] In yet another embodiment the invention provides Primers for isolation of SPL5 gene, having seq id no. 3 and 4.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] FIG. 1 . Expression analysis of the SPL5 gene by Real Time PCR at different developmental stages (Root, Leaf, Bud, 0, 6, 9, 12, 19 and 25 DPA) of cotton. Highest expression was found at fiber initiation stage (0 DPA) of fiber development and after that its expression goes down.
[0033] FIG. 2 . Squamosa promoter binding protein-like transcription factor 5 transcript structure showing microRNA 156 target site in its 3′ UTR (Untranslated) region. The miR 156 binding site distribution is schematically represented.
[0034] FIG. 3 . The construction of full length SPL5 expression cassette. Lane 1, 2, 3, 4, 5, 6 are positive clone and lane 7 is 100 bp marker. Arrow denotes the desired band of 549 of SPL5 coding region.
[0035] FIG. 4 . The construct comprising sense and antisense orientation of 398 bp SPL5 transcript having a gus Intron. This expression cassette when transcribes produces a double stranded small interfering RNA (dsRNA) molecule. Lane 1, Sense strand digested with NcoI and BamHI, arrow shows desired 800 bp band. Lane 2, SPL5 sense and antisense strand digested with NcoI and SpeI resulting in desired 1.2 kb band. Lane 3 and 4 are negative clones. Lane 5 is 1 kb marker and lane 6 is 100 bp marker.
[0036] FIG. 5 . PCR confirmation of transgenic plants by using hptII primer. FIG. 5 a is overexpression line screening and shows that Lane 1, 2, 4, 5, 6, 8, 10, 11 are positive overexpression lines. Lane 3 and 9 are negative lines. Lane 12 positive control and lane 13 is negative control. Lane 7, is 100 bp marker. FIG. 5 b is knockdown line screening which shows lane 1, 4, 5, and 9 are positive knockdown lines whereas lane 2, 3, 6, and 8 are negative lines. Lane 7 is 100 bp marker, lane 10 is positive control and lane 11 is negative control.
[0037] FIG. 6 . Phenotypic analysis of transgenic cotton plants, in FIG. 6 a - b, Higher boll number and size (boll density) is shown in three (A, B and C) independent transgenic lines harbouring CaMV35S-SPL5 overexpression chimeric gene. Further G, H and I show low boll density whereas D, E and F are wild type plants. To differentiate the boll size the flowers were tagged in three different independent lines at 0 DPA of overexpression, knockdown and wild type plant. Interestingly, significant difference was seen at 19 DPA bolls. In FIG. 6 c , lint quantity is shown and in 6 d, seed cotton with lint is shown.
DETAILED DESCRIPTION OF THE INVENTION
[0038] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the compositions and methods described herein belong. Although any methods and materials similar to those described herein can be used in the practice or testing of the present methods and materials, only exemplary methods and materials are described. Real Time PCR (qRT-PCR) is a very accurate measurement technique for expression analysis of genes in molecular biology. qRT-PCR is used to quantify the expression of a particular gene with reference to a housekeeping gene, which is used as a control. The present invention provides a plant growth and development gene (SPL5) identified from microarray data of Cotton. Four SPL family members were selected for functional validation. Real Time PCR of said SPLs was done in root, leaf, bud and six different fiber development stages namely 0 DPA (Zero Day Post Anthesis), 6 DPA, 9 DPA, 12 DPA, 19 DPA, 25 DPA and result showed that only SPL5 out of four SPLs was fiber specific (Example 1).Therefore, this gene was selected for functional validation. The SPL5 transcript encodes a sequence of 731 base pairs having 1 to549 nucleotides coding sequence with a stop codon at 549 nucleotide and 3′ untranslated region from base pair 550 to 731 having a miRNA binding site at 577 to 594.
[0039] siRNAs were first discovered in plants (Hamilton and Baulcombe, Science 286:950-952, 1999; Llave et al, Plant Cell 14:1605-1619, 2002) and play roles in defense against viruses, suppression of expression from transgenes or transposons, establishment of heterochromatin, and post-transcriptional regulation of mRNAs.
[0040] MiRNAs are small (20-24 nt) RNA molecules derived from non-coding miRNA genes found in many organisms (Lee et al, Cell 75:843-854 1993; Wightman et al, Cell 75:855-862, 1993; Reinhart et al, Genes Dev. 16:1616-1626, 2002). miRNAs base-pair with target mRNA sequences in their miRNA binding sites and this binding leads to the down regulation of target mRNA expression. The first case of miRNA regulation was discovered in Caenorhabditis elegans (Lee et al, Cell 75:843-854, 1993; Wightman et al, Cell 75:855-862, 1993), and since that time, many more miRNAs have been found in diverse eukaryotes, with the exception of Saccharomyces cerevisiae. SPL transcription factor family members have microRNA (miRNA) binding sites in their 3′ UTR that are complementary to miRNAs 156 in the cotton genome. The evolutionarily conserved miRNAs are classified into gene families. Thus there are four miRNA 156 (a-d) genes in the cotton genome.
[0041] siRNA and miRNA are chemically and functionally similar. Both are short non-coding RNAs (20-24 nucleotides (nt) in length) whose function is to repress the expression of defined target genes in animals and plants. Both RNA species are generated from longer precursor molecules by a Dicer-like (DCL) ribonuclease and get incorporated into ribonucleoprotein silencing complexes that effect repression of target mRNAs via base pairing of the small RNA and its target mRNA. The silencing complexes require the activity of Argonaut proteins. Repression may occur by cleavage of the target mRNA or inhibition of translation (post-transcriptional regulation) or by methylation of the target gene (transcriptional regulation) (Chen, Science 303:2022-2025, 2004; Bao et al., Dev. Cell. 7:653-662, 2004).
[0042] Studies have also been done, both in vivo and in vitro, to show that SPL mRNAs are cleaved in the presence of miRNA 156 and that this cleavage is dependent upon the miRNA binding site sequence (Pang et al, Genome Biology, 2009). 5′ RACE experiments have also shown that target mRNA is cleaved at a specific position within the miRNA binding site (Wu et. al, Cell 138, 750-759, 2009) and that this cleavage is abolished in the miRNA-resistant SPL mutant.
[0043] Plants that over express the Cotton SPL5 transgene produced higher boll number, size and lint yield. There are two straightforward interpretations of these results: i) the SPL transgene functions at the protein level to cause the boll and lint yield increase, or ii) the SPL transgene functions at the transcriptional level to cause the boll and lint yield increase.
[0044] The protein model (i.e., above) hypothesizes that SPL is transcribed from the transgene into mRNA and then subsequently translated into protein. It is the excess expression of SPL protein from the transgene that is believed to lead to the boll and lint yield increase, presumably by the action of excess SPL protein on inhibition or activation of downstream target genes or by sequestration of other transcriptional factors.
[0045] To distinguish between the opposing protein and transcript models, the present invention generated transgenic events. In one embodiment the event generated a plant carrying transgene that code for a full-length SPL protein and do not contain miRNA binding site. Cotton SPL5 coding sequence without miRNA binding site was engineered containing a translation termination codon at the end of the coding sequence (Example 2).
[0046] In another embodiment, the transgene was silenced by its homologous double stranded small interfering RNA (siRNA) through a process known as RNA interference (RNAi). Plants having the silenced SPL5 transgene decrease in boll number, size and lint percentage in compare to the wild type or a plant which do not comprise the silenced plant growth and development gene (Example 3).
[0047] In the embodiment of the invention, the nucleotide sequence encoding an SPL5 gene is represented in sequence SEQ. I.D. NO.1.
[0048] In the other embodiment of the invention, the amino acid sequence of SPL5 protein is shown in sequence SEQ. I.D. NO.3.
[0049] A number of plant genes have been shown by over expression or suppression analysis to play roles in growth and/or development. Examples of some, but not all, of the genes that are known to be involved in growth and/or development and that can be used or tested in the methods of the present invention are discussed herein below. The Arabidopsis CAP gene, sucrose synthase gene, histone deacetylase 1 gene, E2Fc, BKI gene, BRII gene, Argos-Like (ARL) gene.
[0050] SPLs in plants have been described previously such as in patent publication WO/2011/025840. A SPL gene is involved in the regulation of flower development (Cardon et. al Plant J. 1997, 12, 367-77; Wu et. al, Cell 138, 750-759, 2009), maize kernel development (Wang et al, Nature 2005, 436, 714-719), tomato fruit ripening (Manning et al, Nat. Genet. 2006, 38, 948-952) etc.
[0051] A plant growth and/or development related gene is a gene that plays a role in determining growth rate, overall size, tissue size, or tissue number of a plant or plays a role in the plant developmental program leading to determination of tissue identity and morphology. Such growth and development related genes are identified when modification of their function by mutation, over expression, or suppression of expression results in altered plant growth rate, overall plant size, tissue size or number, or altered development. Plant growth and/or development related genes can exert their effects through a number of mechanisms some of which include regulation of cell cycle, plant hormone synthesis/breakdown pathways, sensitivity to plant hormones, cell wall biosynthesis, cell identity determination, and the like. The plant growth and/or development related genes suitable for use in the disclosed methods also comprise a miRNA binding site and the expression and/or activity of the gene is controlled by the binding of one or more miRNA.
[0052] The term “vector” refers to a piece of DNA, typically double-stranded, which may have inserted into it a piece of foreign DNA. The vector may be of plasmid origin. Vectors contain “replicon” polynucleotide sequences that facilitate the autonomous replication of the vector in a host cell.
[0053] The term “plant” includes whole plants, plant organs, (e.g., leaves, stems, flowers, roots, and the like), seeds and plant cells (including tissue culture cells) and progeny of same. The class of plants which can be used in the methods of the present disclosure is generally as broad as the class of higher plants amenable to transformation techniques, including both monocotyledonous and dicotyledonous plants, as well as certain lower plants such as algae, e.g., cyanobacteria, and the like. It includes plants of a variety of ploidy levels, including polyploid, diploid, hexaploid, tetraploid, haploid, and the like.
[0054] The terms “SPL5 gene” or “SPL5 transgene” are used herein to mean any polynucleotide sequence that encodes or facilitates the expression and/or production of a SPL5 protein. Thus the terms “SPL5 gene” or “SPL5 transgene” can include sequences that flank the SPL5 protein encoding sequences. For example, the sequences can include those nucleotide sequences that are protein encoding sequences (exons), intervening sequences (introns), the flanking 5′ and 3′ DNA regions that contain sequences required for normal expression of the SPL5 gene (i.e., the promoter and polyA addition regions, respectively, and any enhancer sequences).
[0055] The term ‘lint percentage’ means weight of lint cotton obtained in sample/weight of seed cotton in sample ×100.
[0056] The term “substantial identity” of polynucleotide sequences means that a polynucleotide comprises a sequence that has at least 60% sequence identity, typically at least 70%, more typically at least 80% and most typically at least 90%, compared to a reference sequence using the programs described below using standard parameters. One of skill will recognize that these values can be appropriately adjusted to determine corresponding identity of proteins encoded by two nucleotide sequences by taking into account codon degeneracy, amino acid similarity, reading frame positioning and the like.
[0057] Amino acid sequence identity can be determined, for example, in the following manner. The portion of the amino acid sequence of the protein encoded by the growth and/or development associated gene, e.g., SPL5, can be used to search a nucleic acid sequence database, such as the GenBank® database, using the program BLASTP version 2.0.9 (Atschul et al., Nucl. Acids Res. 25:3389-3402, 1997). Sequence comparisons between two (or more) polynucleotides or polypeptides are typically performed by comparing sequences of the two sequences over a “comparison window” to identify and compare local regions of sequence similarity.
[0058] Another example of an algorithm that is suitable for determining percent sequence identity and sequence similarity is the BLAST algorithm, which is described in Altschul et al., J. Mol. Biol. 215:403-410, 1990. Software for performing BLAST analyses is publicly available through the National Center for Biotechnology Information web site. This algorithm involves first identifying high scoring sequence pairs (HSPs) by identifying short words of length W in the query sequence, which either match or satisfy some positive-valued threshold score T when aligned with a word of the same length in a database sequence. T is referred to as the neighborhood word score threshold (Altschul et al., supra). These initial neighborhood word hits act as seeds for initiating searches to find longer HSPs containing them. The word hits are then extended in both directions along each sequence for as long as the cumulative alignment score can be increased. Extension of the word hits in each direction is halted when: the cumulative alignment score falls off by the quantity X from its maximum achieved value; the cumulative score goes to zero or below, due to the accumulation of one or more negative-scoring residue alignments; or the end of either sequence is reached. The BLAST algorithm parameters W, T, and X determine the sensitivity and the speed of the alignment. The BLAST program uses as defaults a wordlength (W) of 11, the BLOSUM62 scoring matrix (see, Henikoff et al, Proc. Natl. Acad. Sci. USA 89:10915-10919, 1992) alignments (B) of 50, expectation (E) of 10, M=5, N=−4, and a comparison of both strands.
[0059] In addition to calculating percent sequence identity, the BLAST algorithm also performs statistical analysis of the similarity between two sequences (see e.g., Karlin et al., Proc. Natl. Acad. Sci. USA 90:5873-5877, 1993). One measure of similarity provided by the BLAST algorithm is the smallest sum probability (P(N)), which provides an indication of the probability by which a match between two nucleotide or amino acid sequences would occur by chance. For example, a nucleic acid is considered similar to a reference sequence if the smallest sum probability in a comparison test is less than about 0.1, more preferably less than about 0.01, and most preferably less than about 0.001. Additional methods and algorithms for sequence alignment and analysis of sequence similarity are well known to the skilled artisan.
[0060] In a particular embodiment of the present disclosure the SPL5 gene sequence used is that from Cotton.
[0061] In general, a suitable promoter is being operably linked to a plant growth and/or development associated gene and expressed using the described methods of the present invention typically has constitutive expression in all plant tissues.
[0062] The tissue obtained from the plant to culture is called an explant. Based on work with certain model systems, particularly tobacco, it has often been claimed that a totipotent explant can be grown from any part of the plant. However, this concept has been vitiated in practice. In many species explants of various organs vary in their rates of growth and regeneration, while some do not grow at all. The choice of explant material also determines if the plantlets developed via tissue culture are haploid or diploid. Also the risk of microbial contamination is increased with inappropriate explants. Thus it is very important that an appropriate choice of explant be made prior to tissue culture.
[0063] An alternative for obtaining uncontaminated explants is to take explants from seedlings which are aseptically grown from surface-sterilized seeds. The hard surface of the seed is less permeable to penetration of harsh surface sterilizing agents, such as hypochlorite, so the acceptable conditions of sterilization used for seeds can be much more stringent than for vegetative tissues.
[0064] Tissue cultured plants are clones, if the original mother plant used to produce the first explants is susceptible to a pathogen or environmental condition, the entire crop would be susceptible to the same problem, and conversely any positive traits would remain within the line also. Plant tissue culture is used widely in plant science; it also has a number of commercial applications (Example 4).
[0065] It is the excess expression of SPL protein from the transgene that is believed to lead to the boll number, size and lint percentage increase, presumably by the action of excess SPL protein on inhibition or activation of downstream target genes or by sequestration of other transcriptional factors; whereas, low expression of SPL protein from the transgene leads to decrease in boll number, size and lint percentage (Example 5).
[0066] The present invention relates to monocotyledonous or a dicotyledonous plant transformation, wherein the plant is selected from a group consisting of tobacco, cotton, rice, wheat, corn, potato, tomato, oilseed rape, alfalfa, sunflower, onion, clover, soyabean, pea.
[0067] One embodiment provides Agrobacterium strain selected from a group consisting of GV3101, LBA4404, EHA 101 and EHA 105.
[0068] Another embodiment provides explant selected from a group consisting of leaf, stem, root, hypocotyls and embryo.
[0069] Yet another embodiment provides a transformed plant cell comprising the recombinant construct.
[0070] Still another embodiment provides a transgenic plant transformed with the recombinant construct.
[0071] Yet another embodiment provides a plant, a plant part, a seed, a plant cell and a progeny thereof, wherein the plant, plant part, seed, plant cell, or progeny thereof comprises the recombinant construct.
[0072] A “cloning vector” is a DNA molecule, such as a plasmid, cosmid, or bacteriophage that has the capability of replicating autonomously in a host cell. Cloning vectors typically contain one or a small number of restriction endonuclease recognition sites at which foreign DNA sequences can be inserted in a determinable fashion without loss of an essential biological function of the vector, as well as a marker gene that is suitable for use in the identification and selection of cells transformed with the cloning vector. Marker genes typically include genes that provide antibiotic or herbicide resistance.
[0073] A “binary vector” is able to replicate in both E. coli and Agrobacterium tumefaciens. It typically contains a foreign DNA in place of T-DNA, the left and right T-DNA borders, marker for selection and maintenance in both E. coli and Agrobacterium tumefaciens, a selectable marker for plants. This plasmid is said to be disarmed since its tumor-inducing genes located in the T-DNA have been removed.
[0074] A “recombinant vector” is a vector in which a foreign DNA has been inserted.
[0075] An “expression vector” is a vector in which an expression cassette has been genetically engineered.
[0076] An “expression cassette” is a DNA molecule comprising a gene that is expressed in a host cell and a promoter, driving its expression. Typically, gene expression is placed under the control of certain tissue-specific regulatory elements.
[0077] A “promoter” is a region of DNA that facilitates the transcription of a particular gene. Promoters are typically located near the genes they regulate, on the same strand and upstream (towards the 5′ region of the sense strand).
[0078] The term “expression” refers to the biosynthesis of a gene product. For example, in the case of a structural gene, expression involves transcription of the structural gene into mRNA and the translation of mRNA into one or more polypeptides.
[0079] In this disclosure “transformation” is the genetic alteration of plant/bacterial cell resulting from the uptake and expression of foreign genetic material (DNA).
[0080] The term “Intron” refers to a non coding part of a DNA molecule.
[0081] The term “DPA” refers to days after anthesis and anthesis is the opening of flower.
[0082] In one embodiment cotton fiber candidate gene was identified.
[0083] In another embodiment gene was amplified from cotton.
[0084] In another embodiment expression of gene was quantified.
[0085] Yet another embodiment gene was cloned in a suitable plant overexpression vector.
[0086] Yet another embodiment gene was cloned in suitable plant knockdown vector.
[0087] Yet another embodiment overexpression and knockdown vectors were transformed into cotton through agrobacterium mediated.
[0088] The examples further describe the construction of an expression vector comprising an appropriate promoter and a modified gene with a role in plant growth and/or development. In particular, in some embodiments, the constitutive promoter CaMV35S was operative associated with the cotton SPL5 coding region (cds) that that comprises no miRNA binding site whereas in other case CaMV35S is associated with truncated SPL5 transcript flanking a gus intron in a RNAi expression module. These constructs were used to produce transgenic cotton plants.
EXAMPLES
[0089] The following examples are given by way of illustration therefore should not be construed to limit the scope of the invention.
[0090] Abbreviations Used:
[0091] DPA: Day Post Anthesis
[0092] q-RT PCR: Quantitative Reverse Transcription-Polymerase Chain Reaction miRNA: microRNA
[0093] SPL: Squamosa Promoter Binding like Transcription Factor
Example 1
[0094] Expression Analysis of SPL5 Gene at Different Developmental Stages of Cotton
[0095] Total RNA was isolated using RNA isolation kit (Sigma-Aldrich) from field grown Cotton plants (of J.K. Agri-genetics Pvt. Ltd., Hyderabad, India) at different developmental stages namely Root, Leaf, Bud, 0 DPA, 6 DPA, 9 DPA, 12 DPA, 19 DPA, 25 DPA. After DNase I treatment (Ambion), RNA was quantified and checked for the integrity by using a Bioanalyzer 2100 (Agilent, Inc., Palo Alto, Calif., USA). 2 μg of DNase treated RNA was used for cDNA preparation using oligo dT primer by SuperScript® cDNA Synthesis Kit (Invitrogen) in 20 μl. The cDNA products were then diluted 10-fold with deionized water before use as a template in real-time PCR. The quantitative reaction was performed on ABI 7500 Real-Time PCR Detection System (Applied Biosystems) using the SYBR Green PCR Master Mix (Applied Biosystems, CA). The reaction mixture (10 μL) contained 5× SYBR Green PCR Master mix, 1 μl (10 pmol) each of the forward and reverse primers and 1μL of cDNA. All experiments were done in three biological replicates and two technical replicates. PCR amplification was performed under the following conditions: 95° C. for 20 s, followed by 40 cycles of 95° C. for 3 s and 62° C. for 30 s. The expressions of transcripts were normalized against an internal reference ubiquitine GhUBQ14 (Artico et al. 2010) gene. The relative gene expression was calculated using the 2̂ −ΔΔCt method. The expression of transcript was highest at 0 DPA of fiber developmental stage i.e. initiation stage of fiber development ( FIG. 1 ).
Example 2
[0096] Construction of Over Expression Module
[0097] Complete SPL5 gene ORF (isolated from cDNA by using primer of sequence I.D. 2) of 549 bp ( FIG. 2 ) was cloned into EcoRV digested SK + and then sub-cloned into NcoI/BstEII digested pCAMBIA 1301 binary vector. The resultant pCAMBIA 1301 (of Cambia Institute, Canberra, Australia) carrying the Overexpression module was transformed into cotton via Agrobacterium tumefaciens strain GV3101 (DNA Cloning Services; Hamburg, Germany) following the modified protocol (Cangelosi et al., 1991) ( FIG. 3 ).
Example 3
[0098] Construction of Knock Down (RNAi) Expression Module
[0099] The 398 bp sequence of SPL5 having AscI and SwaI restriction enzyme site at 5′ end and BamHI and SpeI at 3′ end was cloned into Sk + vector. The knockdown module of SPL5 was made by first digesting with AscI and SwaI and this fragment was cloned into sense direction and Further to clone into antisense direction the construct was digested with BamHI and SpeI. These sense and antisense fragments were sub-cloned into Binary vector PFGC 1008 (of Arabidopsis Biological Resource Centre, Columbus, USA). The resultant PFGC 1008 carrying the knockdown module was transformed into cotton via Agrobacterium tumefaciens strain GV3101 following the modified protocol (Cangelosi et al., 1991) ( FIG. 4 ).
Example 4
[0100] Transformation of Cotton Plants
[0101] Single isolated colony of A. tumefaciens LBA 4404 harboring binary vector containing kanamycin resistance gene for Overexpression and chloramphenicol for knockdown expression as selection marker was inoculated in YEB medium containing antibiotics streptomycin (250 μn/ml) rifampicin (50 μg/ml) and kanamycin (100 μg/ml) and grown (200 rpm, overnight, 28° C.). Fifty micro liters of the overnight culture was diluted to 100 ml in YEB medium and grown till OD 600 reached to 0.8. Cells were recovered by centrifugation in SS34 rotor (5,000 rpm, 10 min, 4° C.). The pellet was suspended in co-cultivation medium (MS salts, 2% glucose, 10 mM MES and 100 mM acetosyrengone, pH 5.6) to OD 600 0.6. Coker-312 seeds were surface sterilized with. 1% HgCl 2 solution for 5 minutes. Sterilized seeds were then finally kept in growtech under moist condition for germination. Germinated seeds were used for embryo transformation. Injuries were induced at arial meristemetic region via cut. Injured seeds were then finally incubated with bacterial cell, dissolved in MSO media having 100 uM Acetosyringone for overnight. After incubation with bacterial cell seeds were transferred in ½ MS media containing 0.2% phytagel and cocultivated for 2 days under dark condition. After co cultivation seeds were washed with cefotaxime (250 mg/l) to remove bacterial cells and transfer in test tube over paper Bridge containing ½ MS liquid media till it convert to plantlets. Plantlets then transferred to soil for hardening and then finally in glass house for proper growth.
Example 5
[0102] Analysis of Transgenic Lines for Transgene Integration and Phenotypic Evaluation
[0103] Genomic DNA of the transgenic lines and control plant was isolated by CTAB method of DNA extraction. The genomic DNA was used as template to amplify a fragment of 900 bp hygromycin gene by using one set of primers 5′-ACACAGCCATCGGTCCAGAC-3′ and 5′-GACGTCTGTCGAGAAGTTTCTGA-3′. The PCR reaction consisted of 94° C. for 4 min, 94° C. for 1 min, 58° C. for 30 sec and 72° C. for 1 min, Go to 2 for 30 cycles 72° C. for 5 min. The desired band of 900 bp was obtained in the PCR of transgenic lines and positive control but not in control (Wild type) plants and negative control (without template). This experiment was repeated for three times for conformation ( FIGS. 5 and 6 ). T0 seeds from selected events were grown as segregating Ti populations in transgenic glass house. Fifty T0 seeds of overexpression line and fifty T0 seeds of knockdown line were grown in soil pot in glass house. Six null plants lacking the transgene were also grown as a control. Since the plants were co-transformed with the hptll resistance gene as a selectable marker, only those plants will give PCR positive that carry the transgene. Fourteen overexpression and fourteen knockdown transgenic lines at T1 generation were found to be positive. Further, phenotypic evaluation determined that overexpression lines had ˜5.8 boll/plant and ˜5.8 gm lint/plant whereas knockdown lines had ˜2.8 boll/plant and 3.2 gm lint/plant in compared to wild type ( FIGS. 7&8 ).
Advantages of the Invention
[0104] Boll number and boll size are the basic yield components of cotton. In order to improve the characteristics or yield of cotton fibre, a gene has been found whose regulated expression is associated with increased boll number, size and lint percentage. Hitherto there is no report to modulate the boll density by modifying a transgene in cotton. | The present invention provides a method for producing transgenic Cotton plants. In one method transformed plants, that overexpress the transgene shows a phenotype that includes increased boll number, size and lint percentage in compare to the wild type plants; whereas in the second method transformed plants that reduced the transgene level produced plants with decreased number of cotton boll, size and lint percentage in compare to wild type and overexpression line both. q-RT PCR analysis showed that transgene transcript level was higher at fiber initiation stage (0 DPA) after that its level decreases throughout all developmental stages. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/751,625, filed on Jan. 11, 2013. The specification and drawings of the provisional patent application are specifically incorporated by reference herein. This application is related to co-pending and commonly assigned U.S. Application No. (Attorney Docket R087 2240US.1).
TECHNICAL FIELD
[0002] The present invention generally relates to gas operating systems for firearms and, more particularly, to automatic gas regulation systems for firearms.
BACKGROUND OF THE INVENTION
[0003] Semi-automatic firearms, such as rifles and shotguns, are designed to fire a round of ammunition, such as a cartridge or shotshell, in response to each squeeze of the trigger of the firearm, and thereafter automatically load the next shell or cartridge from the firearm magazine into the chamber of the firearm. During firing, the primer of the round of ammunition ignites the propellant (powder) inside the round, producing an expanding column of high pressure gases within the chamber and barrel of the firearm. The force of this expanding gas propels the bullet/shot of the cartridge or shell down the barrel.
[0004] In standard auto loading rifles, the addition of a silencer or suppressor to the muzzle of the weapon generates an increase in operating energy, causing the rifle to cycle faster than it would normally cycle if the suppressor were not installed. In known systems, the operator manually switches a gas regulating device to modify the operating characteristics of the weapon to compensate for this increased cyclic rate. This manual switch will typically have a lever or rotational plug that requires the operator to manually switch the system from one setting to the other. In a manually switched gas system, gases are either diverted (bled off) or restricted in order to reduce the overall energy available to operate the firearm.
SUMMARY
[0005] The disclosed embodiments are directed to a mechanism to automatically regulate the operating speed of a weapon having a gas operating system by restricting the gas flow from the firing of a projectile. The embodiments describe a system and methods in which the action of installing a suppressor on the weapon actuates a regulating mechanism to reduce the energy available to drive a gas operating system by restricting the gas flow from the barrel to the gas operating system and to substantially match operating speeds between suppressed and unsuppressed operation.
[0006] In an autoloading firearm, installing a sound suppressor (silencer) on the weapon typically can cause the cyclic operation of the weapon to speed up due to residual pressures in the suppressor and bore of the weapon. Commonly available systems require the manual activation of a regulator to reduce the initial energy available to the operating system to balance the extra energy imparted by the residual bore pressure.
[0007] In one embodiment having a gas regulation system, when a suppressor is not attached to the muzzle, a gas port in the barrel is free to provide energy to cycle the weapon. When a suppressor is attached to the muzzle, the suppressor depresses a regulator plunger which restricts gas flow from the gas port, reducing the amount of gas entering the system to cycle the weapon. The regulator plunger returns to a spring-biased forward position in the gas block when the suppressor is removed.
[0008] In another embodiment, an auto regulating gas system is provided for an auto loading firearm. The auto regulating gas system includes a gas block attached to a barrel of the firearm to redirect a volume of propellant gases, the gas block including a gas port for directing propellant gases received from a gas port of the barrel into a gas tube to cycle the auto loading firearm. A spring-loaded plunger assembly is positioned within the gas block, the plunger assembly including a regulator plunger having a reduced flow orifice, a regulator bushing, a regulator spring, and a regulator cap, wherein the position of the regulator plunger within the gas block automatically controls an amount of gas that is allowed to enter the gas system. Mounting a muzzle device, such as a suppressor over the muzzle drives the regulator plunger rearward moving the reduced flow orifice over the gas port in the gas block to automatically reduce the volume of propellant gases directed into the gas system.
[0009] In a further embodiment, an auto regulating gas system is provided for an auto loading firearm. The auto regulating system includes a gas block attached to the barrel to redirect a volume of propellant gases to cycle the auto loading weapon, the gas block including a gas port for directing propellant gases received from the a gas port of the barrel into the gas system. A spring-loaded plunger assembly is positioned within the gas block, the plunger assembly including a regulator plunger having a reduced flow orifice, a regulator bushing, a regulator spring, and a regulator cap, wherein the position of the regulator plunger within the gas block automatically controls an amount of gas that is allowed to enter the gas system. A mechanical backup linkage assembly is attached to the gas block for returning the regulator plunger to a forward position in the gas block when a muzzle device mounted on a muzzle of the firearm is removed.
[0010] These and other advantages and aspects of the embodiments of the disclosure will become apparent and more readily appreciated from the following detailed description of the embodiments taken in conjunction with the accompanying drawings, as follows. It further will be understood that the present drawings may not necessarily be drawn to scale and dimensions therein are for illustrative purposes and should not be taken as limiting the scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 illustrates a side view of the auto regulating gas system and mechanical linkage assembly when a suppressor is not installed in accordance with an exemplary embodiment.
[0012] FIG. 2 illustrates a side cross-sectional view of the auto regulating gas system and mechanical backup linkage assembly when a suppressor is not installed in accordance with an exemplary embodiment.
[0013] FIG. 3 illustrates a side cross-sectional view of the auto regulating gas system and mechanical backup linkage assembly when a suppressor is installed in accordance with an exemplary embodiment.
[0014] FIG. 4 illustrates an isometric view of the auto regulating gas system and mechanical backup linkage assembly when a suppressor is not installed in accordance with an exemplary embodiment.
[0015] FIG. 5 illustrates an isometric view of the auto regulating gas system and mechanical backup linkage assembly when a suppressor is installed in accordance with an exemplary embodiment.
[0016] FIG. 6 illustrates an isometric view of the auto regulating gas system and mechanical backup linkage assembly in an unsuppressed mode in another embodiment.
[0017] FIG. 7 illustrates a side view of the auto regulating gas system and mechanical backup linkage assembly of FIG. 6 in an unsuppressed mode.
[0018] FIG. 8 illustrates a side view of the auto regulating gas system and mechanical backup linkage assembly of FIG. 6 in a suppressed mode.
[0019] FIG. 9 illustrates an isometric view of the auto regulating gas system and mechanical backup linkage assembly of FIG. 6 in a suppressed mode.
DETAILED DESCRIPTION
[0020] The following description is provided as an enabling teaching of embodiments of the invention. Those skilled in the relevant art will recognize that many changes can be made to the embodiments described, while still obtaining the beneficial results. It will also be apparent that some of the desired benefits of the embodiments described can be obtained by selecting some of the features of the embodiments without utilizing other features. Accordingly, those who work in the art will recognize that many modifications and adaptations to the embodiments described are possible and may even be desirable in certain circumstances. Thus, the following description is provided as illustrative of the principles of the invention and not in limitation thereof, since the scope of the invention is defined by the claims.
[0021] There have been documented cases of weapon failing to operate when users fail to switch the weapons from unsuppressed to suppressed operation or vice versa when installing or removing a suppressor. The disclosed embodiments provide a means to automatically switch the weapon between these two states, thereby assuring proper weapon operation.
[0022] In related, co-pending, commonly-owned patent application, serial number (Attorney Docket No. R087 2240US.1), incorporated by reference herein, two separate gas ports in the barrel are utilized and one port is sealed off when a suppressor is installed. In the embodiments described herein, a single port in the barrel can be utilized and the flow of gases from the port can be restricted by an opening in a regulator plunger that aligns with the corresponding ports in the barrel and gas block when a suppressor is installed. A mechanical backup assist system is also provided. In this embodiment, an auto loading weapon is cycled utilizing propulsion gases from the firing of a cartridge. Gases are bled off from the barrel of the weapon and can be diverted to operate either a piston in a piston driven weapon, or to directly operate the bolt and bolt carrier in a direct gas impingement weapon. In either system, the installation of a suppressor or silencer typically increases the operating velocity of the bolt and bolt carrier, which is detrimental to the longevity and functional reliability of the weapon. The disclosed embodiments do not utilize a manually switched gas system to either divert (bleed off) or restrict gases in order to reduce the overall energy available to operate the firearm.
[0023] As depicted in FIGS. 1-5 , in one exemplary embodiment, the gas-operated mechanism of an auto loading rifle F can be adjusted automatically when a suppressor 40 is attached to the muzzle of the rifle. The operating characteristics of the weapon are changed automatically with the installation of a suppressor 40 or other muzzle device, such as a blank firing adapter. The automatic regulating gas system could be applied to both direct gas impingement operated weapons and piston operated weapons. An embodiment is described below, and in the accompanying drawings, in which the automatic regulating gas system is applied to a direct impingement system. A mechanical backup linkage assembly 50 is also disclosed for the automatic regulating gas system to provide both a visual indication of the firearm's setting (suppressed or unsuppressed) and a manual backup of the regulating system should the automatic regulating gas system fail to switch positions from suppressed to unsuppressed mode in which the plunger is spring-based forward.
[0024] FIG. 1 illustrates a side view of the auto regulating gas system and mechanical linkage assembly when a suppressor is not installed. It depicts a firearm F having a barrel 30 with a flash hider 20 installed on the muzzle end. Also shown are gas block 34 , accessory rail 60 , plunger assembly regulator cap 18 , and mechanical linkage assembly 50 . The mechanical linkage assembly 50 includes a lever or paddle 52 , and links 54 , 56 . Identical links generally are installed on the opposite side of the firearm with regulator plunger retaining pin 28 also serving as the pivot point for the linkage assembly. FIGS. 1-4 further show a flash hider 20 installed on the muzzle end of barrel 30 . Also shown in FIGS. 1-5 is the mounting rail 60 extending over the gas block 34 .
[0025] The barrel 30 for an autoloading rifle may have a suppressor 40 attached to the muzzle end of the weapon. The suppressor 40 can be installed over flash hider 20 as shown in FIGS. 3 and 5 . The barrel 30 will include a chamber to accept a cartridge, a bore, one or more gas orifices (ports) 22 , and a muzzle.
[0026] The gas block 34 can be attached to the barrel 30 to redirect the propellant gases to cycle the action of the weapon either through the use of a gas tube 36 , shown in FIGS. 2-3 , that redirects the gases into the bolt carrier group in a direct impingement rifle, or into a piston system that cycles the weapon with direct mechanical force.
[0027] FIGS. 2-3 illustrate side cross-sectional views of the auto regulating gas system without and with a suppressor installed, respectively. In this exemplary embodiment, in a direct impingement weapon, the barrel 30 includes a gas port 22 that redirects propellant gases from the bore of the barrel into a gas passage 24 within the gas block 34 . With a suppressor installed ( FIG. 3 ), the suppressor 40 can engage a regulator plunger 12 , which at least partially closes or restricts the passage of gases through the gas port 22 such that the gas port 22 and gas passage 24 redirect the propellant gas through a restricted opening 26 in the regulator plunger 12 into the gas tube 36 . The propellant gas is then passed down the gas tube 36 into the bolt carrier group (not shown) where the gas acts in a standard method to cycle the action of the weapon.
[0028] As illustrated in FIGS. 1-4 , the regulator plunger assembly 10 generally can operate co-axially with the bore of the weapon. The regulator plunger assembly 10 is spring-loaded to bias the plunger assembly 10 to the forward position, referred to herein as the “unsuppressed” setting. The regulator plunger assembly 10 operates in a bore of a gas block 34 co-axial to the bore of the weapon. The gas block 34 has a passage or passages 24 that correspond to ports 22 in the barrel 30 that are roughly perpendicular to the bore of the weapon and serve to bleed off propulsion gases for the purpose of cycling the weapon. The gas block 34 diverts these operating gases into either a piston chamber in a piston operated weapon, or into a gas tube 36 via a counter bore 32 in the plunger that provides passage for the operating gases back to the bolt carrier group in a gas impingement weapon.
[0029] In one embodiment, the spring loaded plunger assembly 10 can be positioned within a larger bore of the gas block 34 and will be oriented parallel with the bore of the barrel 30 of firearm F. As also show in FIG. 4 , a flash hider/flash suppressor 20 could be mounted over the muzzle end of barrel 30 . The plunger assembly 10 can include a regulator plunger 12 , regulator bushing 14 , regulator spring 16 , and regulator cap 18 . The regulator plunger 12 includes a restricted opening (i.e., reduced flow orifice) that aligns with the barrel port 22 and gas block port 24 when the regulator plunger is moved rearward by mounting of the muzzle device. The plunger assembly 10 may be removed from the gas block 34 as a unit or substantially unitary assembly, and can be retained by a cross pin 28 to prevent forward and rearward motion of the regulator bushing 14 , which cross pin 28 also can serve as the primary pivot point for the mechanical linkage assembly 50 .
[0030] The mechanical backup linkage assembly 50 includes a top lever or paddle 52 , with links 54 , 56 mounted along the sides of the mechanical backup linkage assembly 50 . The mechanical backup linkage assembly 50 provides a mechanical assist or backup to the spring loaded return system of the regulator plunger 12 . Should the regulator plunger 12 not return to the unsuppressed, forward biased condition when the suppressor 40 is removed, the linkage assembly 50 provides a mechanical advantage to the operator in forcing the plunger 12 forward.
[0031] As shown in FIGS. 2-3 , a larger diameter section of the regulator plunger 12 generally operates within the regulator bore of the gas block 34 and interfaces with the rear surface of the regulator bushing 14 when the plunger is held forward by the regulator spring 16 . This interface surface prevents the forward flow of propellant gases from exiting the gas block 34 . As also indicated in FIGS. 2-3 , another smaller diameter section of the regulator plunger 12 extends through the regulator bushing 14 and towards the front end of the gas block 34 . The regulator cap 18 slides over the end of the small diameter of the regulator plunger 12 and is retained by a cross pin 28 . The regulator cap 18 captures the regulator spring 16 in a slightly compressed state between the forward face of the regulator bushing 14 and the regulator cap 18 . The regulator spring 16 operates within the regulator bore on the gas block 34 and surrounds the small diameter of the regulator plunger 12 . The regulator cap 18 extends out the front end of the gas block 34 towards the muzzle.
[0032] When the weapon fires unsuppressed, the regulator plunger 12 may cycle backward on contra-recoil, wiping the surfaces of the bore/gas passage 24 of the gas block to keep carbon from building up. A seal between the regulator plunger 12 and regulator bushing 14 prevents gas from getting into the regulator spring 16 . The regulator plunger 12 , in the unsuppressed setting, does not alter the operating characteristics of the weapon. However, when a suppressor 40 or other muzzle device is installed onto the muzzle of the weapon, the regulator plunger 12 is depressed through the action of installing the suppressor 40 . The regulator plunger 12 contains reduced flow orifice 26 that is introduced over the gas passage 24 in the gas block to restrict the flow of gases from the gas port 22 on the barrel 30 into the counter bore 32 and gas tube 36 . This restricted gas flow is sized so that the operating velocity of a weapon with the suppressor 40 installed roughly matches the operating velocity of an unsuppressed weapon. When the suppressor 40 is removed from the muzzle of the weapon, the spring loaded plunger 12 returns to its forward position, allowing unrestricted gas flow from the barrel 30 to the operating system of the weapon.
[0033] In other embodiments, the installation of other muzzle devices, such as grenade launchers and adapters for the use of blank firing ammunition, could also require a restriction in the gas available to operate the weapon to prevent overspeed conditions. These muzzle devices could be designed in such a way to operate the regulator plunger in a manner identical to the suppressor installation, thereby restricting the operating gases and maintaining the proper operating speed of the weapon.
[0034] In operation, as illustrated in FIG. 4 , in the unsuppressed mode, the lever (paddle) 52 is forced forward by the spring-biased return spring (not shown) of the plunger assembly and is attached above the plunger 12 and horizontal to the bore. In the suppressed mode, as illustrated in FIG. 5 , the plunger 12 lifts the assist lever 52 as it is depressed by the suppressor 40 , thereby providing a highly visible indicator of the plunger position. Pushing down on the paddle 52 provides a strong mechanical advantage forcing the plunger 12 back to the unsuppressed setting. The mechanical advantage afforded by the lever 52 would only be used as a backup to the plunger spring system and in the case of extreme fouling. The entire mechanical backup linkage assembly 50 and plunger assembly 10 can be removed without the use of any tools by pressing a detented cross pin 28 on the left side of the firearm F and lifting the lever 52 . The lever 52 then can be used as a grip to pull out the plunger assembly 10 . The detented cross pin 28 retains the plunger cartridge and acts as a fixed pivot for the mechanical backup linkage assembly 50 .
[0035] FIGS. 6-9 illustrate another embodiment in which the links of the mechanical backup linkage assembly 50 can be of a reduced or shorter length or size than in the embodiment illustrated in FIGS. 1-5 . Operation of both embodiments remains the same. FIG. 6 illustrates an isometric view of the auto regulating gas system and mechanical linkage assembly in an unsuppressed mode. FIG. 7 illustrates a side view of the auto regulating gas system and mechanical linkage assembly of FIG. 6 in an unsuppressed mode. The links 54 , 56 in the mechanical linkage assembly 50 generally will be sized such that the lever 52 cannot be adjusted to a vertical position since the lever 52 could then interfere with firearm accessories positioned on handguard/accessory rail 60 . FIG. 8 illustrates a side view of the auto regulating gas system and mechanical linkage assembly of FIG. 6 in a suppressed mode. FIG. 9 illustrates an isometric view of the auto regulating gas system and mechanical linkage assembly in a suppressed mode.
[0036] The corresponding structures, materials, acts, and equivalents of all means plus function elements in any claims below are intended to include any structure, material, or acts for performing the function in combination with other claim elements as specifically claimed.
[0037] Those skilled in the art will appreciate that many modifications to the exemplary embodiments are possible without departing from the scope of the present invention. In addition, it is possible to use some of the features of the embodiments disclosed without the corresponding use of the other features. Accordingly, the foregoing description of the exemplary embodiments is provided for the purpose of illustrating the principles of the invention, and not in limitation thereof, since the scope of the invention is defined solely by the appended claims. | An auto regulating gas system to automatically regulate the operating speed of an auto loading weapon having a gas operating system by restricting the gas flow from the firing of a projectile. A gas block attached to the barrel or the weapon redirects a volume of propellant gases to cycle the weapon, the gas block including a gas port for directing propellant gases received from the a gas port of the barrel into the gas system. A spring-loaded plunger assembly is positioned within the gas block, the plunger assembly including a regulator plunger having a reduced flow orifice, a regulator bushing, a regulator spring, and a regulator cap, wherein the position of the regulator plunger within the gas block automatically controls an amount of gas that is allowed to enter the gas system. A mechanical backup linkage assembly is attached to the gas block as a backup device for returning the regulator plunger to a forward position in the gas block when a muzzle device mounted on a muzzle of the firearm is removed. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This utility application is a continuation of U.S. Ser. No. 11/854,145, filed Sep. 12, 2007 now U.S. Pat. No. 7,988,332, which claims benefit, under 35 U.S.C. §119(e), of U.S. Provisional Patent Application Ser. No. 60/844,184, filed Sep. 12, 2006, the entirety of which is incorporated herein by reference.
Throughout this application, several publications are referenced. Disclosure of these references in their entirety is hereby incorporated by reference into this application.
The present invention relates to light wires and, more specifically, an integrally formed single piece of light wire containing light emitting diodes (“LEDs”), and systems and processes for manufacturing such a light wire, wherein the LEDs and associated circuitry are protected from mechanical damage and environmental hazards, such as water and dust.
BACKGROUND THE INVENTION
Conventional incandescent or LED light wires are commonly used in a variety of indoor and outdoor decorative or ornamental lighting applications. For example, such conventional light wires are used to create festive holiday signs, outline architectural structures such as buildings or harbors, and provide under-car lighting systems. These light wires are also used as emergency lighting aids to increase visibility and communication at night or when conditions, such as power outages, water immersion and smoke caused by fires and chemical fog, render normal ambient lighting insufficient for visibility.
Conventional LED light wires consume less power, exhibit a longer lifespan, are relatively inexpensive to manufacture, and are easier to install when compared to light tubes using incandescent light bulbs. More increasingly, LED light wires are used as viable replacements for neon light tubing.
As illustrated in FIG. 1 , conventional light wire 100 consists of a plurality of illuminant devices 102 , such as incandescent light bulbs or LEDs, connected together by a flexible wire 101 and encapsulated in a protective tube 103 . A power source 105 creates an electrical current that flows through the flexible wire 101 causing the illuminant devices 102 to illuminate and create an effect of an illuminated wire. The illuminant devices 102 are connected in series, parallel, or in combination thereof. Also, the illuminant devices 102 are connected with control electronics in such a way that individual illuminant devices 102 may be selectively switched on or off to create a combination of light patterns, such as strobe, flash, chase, or pulse.
In conventional light wires, the protective tube 103 is traditionally a hollow, transparent or semi-transparent tube which houses the internal circuitry (e.g., illuminant devices 102 ; flexible wire 101 ). Since there is an air gap between the protective tube 103 and internal circuitry, the protective tube 103 provides little protection for the light wire against mechanical damage due to excessive loads, such as the weight of machinery that is directly applied to the light wire. Furthermore, the protective tube 103 does not sufficiently protect the internal circuitry from environmental hazards, such as water and dust. As a result, these conventional light wires 100 with protective tube 103 are found unsuitable for outdoor use, especially when the light wires are exposed to extreme weather and/or mechanical abuse.
In conventional light wires, wires, such as flexible wire 101 , are used to connect the illuminant devices 102 together. In terms of manufacturing, these light wires are traditionally pre-assembled using soldering or crimp methods and then encapsulated via a conventional sheet or hard lamination process in protective tube 103 . Such processes of manufacturing are labor intensive and unreliable. Furthermore, such processes decrease the flexibility of the light wire.
In response to the above-mentioned limitations associated with the above-mentioned conventional light wires and the manufacture thereof, LED light strips have been developed with increased complexity and protection. These LED light strips consist of circuitry including a plurality of LEDs mounted on a support substrate containing a printed circuit and connected to separate electrical conductors (e.g., two separate conductive bus elements). The LED circuitry and the electrical conductors are encapsulated in a protective encapsulant without internal voids (which includes gas bubbles) or impurities, and are connected to a power source. These LED light strips are manufactured by an automated system that includes a complex LED circuit assembly process and a soft lamination process. Examples of these LED light strips and the manufacture thereof are discussed in U.S. Pat. Nos. 5,848,837, 5,927,845 and 6,673,292, all entitled “Integrally Formed Linear Light Strip With Light Emitting Diode”; U.S. Pat. No. 6,113,248, entitled “Automated System For Manufacturing An LED Light Strip Having An Integrally Formed Connected”; and U.S. Pat. No. 6,673,277, entitled “Method of Manufacturing a Light Guide”.
Although these LED light strips are better protected from mechanical damage and environmental hazards, these LED light strips require additional separate parts, such as a support substrate and two separate conductive bus elements, to construct its internal LED circuitry. Also, to manufacture these LED light strips, additional manufacturing steps, such as purification steps, and equipment are required to assemble the complex LED circuit and painstakingly remove internal voids and impurities in the protective encapsulant. Such additional procedures, parts and equipment increase manufacturing time and costs.
Additionally, just like the conventional light wires discussed above, these LED light strips only provide one-way light direction. Moreover, the complexity of the LED circuitry and lamination process makes the LED light strip too rigid to bend.
SUMMARY OF THE INVENTION
In light of the above, there exists a need to further improve the art. Specifically, there is a need for an improved integrally formed single piece LED light wire that is flexible and provides a smooth, uniform lighting effect from all directions of the integrally formed single piece LED light wire. There is also a need to reduce the number of separate parts required to produce the integrally formed single piece LED light wire. Furthermore, there is also a need for an LED light wire that requires less procedures, parts, and equipment and can therefore be manufactured by a low cost automated process.
An integrally formed single piece LED light wire, comprises a conductive base comprising first and second bus elements formed from a conductive material adapted to distribute power from a power source. At least one light emitting diode (LED) having first and second electrical contacts is mounted on the first and second bus elements so that it draws power from and adds mechanical stability to the first and second bus elements. The first and second bus elements are connected to each other prior to the LED being mounted. The integrally formed single piece LED light wire is formed without a substrate.
According to an embodiment of the integrally formed single piece LED light wire, an encapsulant completely encapsulating the first and second bus elements, and the at least one LED.
According to an embodiment of the integrally formed single piece LED light wire, the encapsulant is textured.
According to an embodiment of the integrally formed single piece LED light wire, the encapsulant includes light scattering particles.
According to an embodiment of the integrally formed single piece LED light wire, a plurality of LEDs, are connected in series.
According to an embodiment of the integrally formed single piece LED light wire, a plurality of LEDs are connected in series and parallel.
According to an embodiment of the integrally formed single piece LED light wire, the first and second bus elements are separated after at least one LED is mounted.
According to an embodiment of the integrally formed single piece LED light wire, a connection between the LED and one of the first and second bus elements is made using solder, welding, or conductive epoxy.
According to an embodiment of the integrally formed single piece LED light wire, a connection between the LED and either the first or second bus elements is made using solder, welding, wire bonding, and conductive epoxy.
According to an embodiment of the integrally formed single piece LED light wire, includes a third bus element formed from a conductive material adapted to distribute power from the power source a plurality of LEDs, a first set LEDs are connected in series and parallel between the first and second bus elements and a second set LEDs are connected in series and parallel between the second and third bus elements.
According to an embodiment of the integrally formed single piece LED light wire, an anode of a first LED is connected to the first bus element and a cathode of the first LED is connected to the second bus element, an anode of a second LED is connected to the second bus element and a cathode of the second LED is connected to the third bus element, and a cathode of a third LED is connected to the first bus element and an anode of the first LED is connected to the second bus element.
According to an embodiment of the integrally formed single piece LED light wire, a cathode of a fourth LED is connected to the second bus element and an anode of the fourth LED is connected to the third bus element.
According to an embodiment of the integrally formed single piece LED light wire, the LEDs are selected from red, blue, green, and white LEDs.
According to an embodiment of the integrally formed single piece LED light wire includes a controller adapted to vary the power provided to the first, second, and third bus elements.
According to an embodiment of the integrally formed single piece LED light wire includes a core about which the conductive base is wound in a spiral manner.
According to an embodiment an integrally formed single piece LED light wire includes a first bus element formed from a conductive material adapted to distribute power from a power source, a second bus element formed from a conductive material adapted to distribute power from the power source, a third bus element formed from a conductive material adapted to distribute a control signal, at least one light emitting diode (LED) module, said LED module comprising a microcontroller and at least one LED, the LED module having first, second, and third electrical contacts, the LED module being mounted on the first, second, and third bus elements so that it draws power from the first and second bus elements and receives a control signal form the third bus element, wherein the integrally formed single piece LED light wire is formed without a substrate.
According to an embodiment of the integrally formed single piece LED light wire, the LED module has a plurality of LEDs selected from the group consisting of red, blue, green, and white LEDs.
According to an embodiment of the integrally formed single piece LED light wire, the LED module includes a fourth contact for outputting the received control signal.
According to an embodiment of the integrally formed single piece LED light wire includes an encapsulant completely encapsulating said first, second, and third bus elements, and said at least one LED module.
According to an embodiment of the integrally formed single piece LED light wire, each LED module has a unique address.
According to an embodiment of the integrally formed single piece LED light wire, the LED module has a static address.
According to an embodiment of the integrally formed single piece LED light wire, the LED module address is dynamic.
An integrally formed single piece LED light wire, comprising: first and second bus elements formed from a conductive material adapted to distribute power from a power source; at least two conductor segments arranged between the first and second bus elements; and at least one light emitting diode (LED), said LED having first and second electrical contacts, the first electrical contact being connected to a first conductor segment and the second electrical contact being connected to a second conductor segment; wherein the first and second conductor segments are coupled to the first and second bus elements to power the LED.
According to an embodiment of the integrally formed single piece LED light wire, includes a flexible substrate, the first and second conductor segments and the first and second bus elements, being supported by the flexible substrate.
According to an embodiment of the integrally formed single piece LED light wire, wherein flexible substrate is wound about a core.
DESCRIPTION OF THE FIGURES
FIG. 1 is a representation of a conventional light wire;
FIG. 2 is a perspective view illustrating an integrally formed single piece LED light wire according to an embodiment of the present invention;
FIG. 3 is a cross-sectional view of an embodiment of the integrally formed single piece LED light wire according to the present invention;
FIG. 4A is a side view of an integrally formed single piece LED light wire according to another embodiment of the present invention;
FIG. 4B is a top view of an integrally formed single piece LED light wire according to another embodiment of the present invention;
FIG. 5 is a cross-sectional view of the integrally formed single piece LED light wire shown in FIGS. 4A & 4B ;
FIG. 6A is an embodiment of the conductive base;
FIG. 6B is a schematic diagram of the conductive base of FIG. 6A ;
FIG. 7A is an embodiment of the conductive base;
FIG. 7B is a schematic diagram of the conductive base of FIG. 7A ;
FIG. 8A is an embodiment of the conductive base;
FIG. 8B is a schematic diagram of the conductive base of FIG. 8A ;
FIG. 9A is an embodiment of the conductive base;
FIG. 9B is a schematic diagram of the conductive base of FIG. 9A ;
FIG. 10A is an embodiment of the conductive base;
FIG. 10B is a schematic diagram of the conductive base of FIG. 10A ;
FIG. 11A is an embodiment of the conductive base;
FIG. 11B is a schematic diagram of the conductive base of FIG. 11A ;
FIG. 11C depicts a conductive base wrapped on a core prior to encapsulation;
FIG. 12A depicts an embodiment of an LED mounting area of a conductive base;
FIG. 12B depicts a mounted LED on a conductive base;
FIG. 13 depicts LED chip bonding in an LED mounting area;
FIG. 14 depicts the optical properties of an embodiment of the invention;
FIGS. 15A-C depict a cross-sectional view of three different surface textures of the encapsulant;
FIG. 16A is a schematic diagram of an integrally formed single piece LED light wire;
FIG. 16B depicts an embodiment of an integrally formed single piece LED light wire;
FIG. 17 is a schematic diagram of a full color integrally formed single piece LED light wire;
FIG. 18 is a schematic diagram of a control circuit for a full color integrally formed single piece LED light wire;
FIG. 19 is a timing diagram for a full color integrally formed single piece LED light wire;
FIG. 20A is a timing diagram for a full color integrally formed single piece LED light wire;
FIG. 20B is a timing diagram for a full color integrally formed single piece LED light wire;
FIG. 21 depicts an LED module;
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to an integrally formed single piece LED light wire containing a plurality of LEDs that are connected to conductors forming a mounting base or conductors supported on insulating material to provide a combined mounting base. Both types of mounting base provides an (1) electrical connection, (2) a physical mounting platform or a mechanical support for the LEDs, and (3) a light reflector for the LEDs. The mounting base and LEDs are encapsulated in a transparent or semi-transparent encapsulant which may contain light scattering particles.
In one embodiment of the present invention, as shown in FIGS. 2 and 3 , an integral single piece LED light wire, which includes a sub-assembly 310 comprising at least one LED 202 connected to a conductive base 201 , wherein the sub-assembly 310 is encapsulated within an encapsulant 303 . As shown in FIG. 2 , the LEDs 202 are connected in series. This embodiment offers the advantage of compactness in size, and allows the production of a long, thin LED light wire with an outer diameter of 3 mm or less. The conductive base 301 is operatively connected to a power source 305 to conduct electricity.
In another embodiment, as illustrated in FIGS. 4A , 4 B, and 5 , the present invention may be an integrally formed single piece LED light wire comprising a plurality of sub-assemblies 510 . Each sub-assembly 510 consists of at least one LED 202 connected to a conductive base 401 . The sub-assemblies 510 are encapsulated within an encapsulant 503 . As shown, the LEDs 202 are connected in parallel. The conductive base 401 is operatively connected to a power source 405 to activate LEDs 202 .
AC or DC power from power source 405 may be used to power the integrally formed single piece LED light wire. Additionally, a current source may be used. Brightness may be controlled by digital or analog controllers.
The conductive base 201 , 401 extends longitudinally along the length of the integrally formed single piece LED light wire, and act as an (1) electrical conductor, (2) a physical mounting platform or a mechanical support for the LEDs 202 , and (3) a light reflector for the LEDs 202 .
The conductive base 201 , 401 may be, for example, punched, stamped, printed, silk-screen printed, or laser cut, or the like, from a metal plate or foil to provide the basis of an electrical circuit, and may be in the form of a thin film or flat strip. In another embodiment, the conductive base 201 , 401 , is formed using stranded wire. Additional circuitry, such as active or passive control circuit components (e.g., a microprocessor, a resistor, a capacitor), may be added and encapsulated within an encapsulant to add functionality to the integrally formed single piece LED light wire. Such functionality may include, but not limited to, current limiting (e.g., resistor), protection, flashing capability, or brightness control. For example, a microcontroller may be included to make the LEDs 202 individually addressable; thereby, enabling the end user to control the illumination of selective LEDs 202 in the LED light wire to form a variety of light patterns, e.g., strobe, flash, chase, or pulse. In one embodiment, external control circuitry is connected to the conductive base 201 , 401 .
The conductive base 201 , 401 may be flexible or rigid, and is made of, but not limited to, thin film PCB material, conductive rod, copper plate, copper clad steel plate, copper clad alloy, or a base material coated with a conductive material.
First Embodiment of the Conductive Base
In a first embodiment of the conductive base assembly 600 , shown in FIG. 6A , the base material of the conductive base 601 is preferably a long thin narrow metal strip or foil. In one embodiment, the base material is copper. A hole pattern 602 , shown as the shaded region of FIG. 6A , depict areas where material from the conductive base 601 has been removed. In one embodiment, the material has been removed by a punching machine. The remaining material of the conductive base 601 forms the circuit of the present invention. Alternatively, the circuit may be printed on the conductive base 601 and then an etching process is used to remove the areas 602 . The pilot holes 605 on the conductive base 600 act as a guide for manufacture and assembly.
The LEDs 202 are mounted either by surface mounting or LED chip bonding and soldered, welded, riveted or otherwise electrically connected to the conductive base 601 as shown in FIG. 6A . The mounting and soldering of the LEDs 202 onto the conductive base 601 not only puts the LEDs 202 into the circuit, but also uses the LEDs 202 to mechanically hold the different unpunched parts of the conductive base 601 together. In this embodiment of the conductive base 601 all of the LEDs 202 are short-circuited, as shown in FIG. 6B . Thus, additional portions of conductive base 601 are removed as discussed below so that the LEDs 202 are not short-circuited. In one embodiment, the material from the conductive base 601 is removed after the LEDs 202 are mounted.
Second Embodiment of the Conductive Base
To create series and/or parallel circuitries, additional material is removed from the conductive base. As shown in FIG. 7A , the conductive base 701 has an alternative hole pattern 702 relative to the hole pattern 602 depicted in FIG. 6A . With the alternative hole pattern 702 , the LEDs 202 are connected in series on the conductive base 701 . The series connection is shown in FIG. 7B , which is a schematic diagram of the conductive base assembly 700 shown in FIG. 7A . As shown, the mounting portions of LEDs 202 provide support for the conductive base 701 .
Third Embodiment of the Conductive Base
In a third embodiment of the conductive base, as shown in FIG. 8A , a conductive base assembly 800 is depicted having a pattern 802 is punched out or etched into the conductive base 801 . Pattern 802 reduces the number of punched-out gaps required and increase the spacing between such gaps. Pilot holes 805 act as a guide for the manufacturing and assembly process. As shown in FIG. 8B , the LEDs 202 are short-circuited without the removal of additional material. In one embodiment, the material from conductive base 801 is removed after the LEDs 202 are mounted.
Fourth Embodiment of the Conductive Base
As illustrated in FIG. 9A , a fourth embodiment of the conductive base assembly 900 contains an alternative hole pattern 902 that, in one embodiment, is absent of any pilot holes. Compared to the third embodiment, more gaps are punched out in order to create two conducting portions in the conductive base 901 . Thus, as shown in FIG. 9B , this embodiment has a working circuit where the LEDs 202 connected in series.
Fifth and Sixth Embodiments of the Conductive Base
FIG. 10A illustrates a fifth embodiment of conductive base assembly 1000 of the conductive base 1001 . Shown is a thin LED light wire with a typical outer diameter of 3 mm or less. As shown in FIG. 10A , (1) the LEDs 202 connected on the conductive base 1001 are placed apart, preferably at a predetermined distance. In a typical application, the LEDs 202 are spaced from 3 cm to 1 m, depending upon, among other things, at least the power of the LEDs used and whether such LEDs are top or side-emitting. The conductive base 1001 is shown absent of any pilot holes. The punched-out gaps that create a first hole pattern 1014 that are straightened into long thin rectangular shapes. LEDs 202 are mounted over punched-out gaps 1030 . However, as shown in FIG. 10B , the resultant circuit for this embodiment is not useful since all the LEDs 202 are short-circuited. In subsequent procedures, additional material is removed from conductive base 1001 so that LEDs 202 are in series or parallel as desired.
In the sixth embodiment of the conductive base assembly 1100 , conductive base 1101 , as shown in FIG. 11A , contains a hole pattern 1118 which creates a working circuit in the conductive base 1101 with a series connections of LEDs 202 mounted onto the conductive base 1101 . This embodiment is useful in creating a thin LED light wire with a typical outside diameter of 3 mm or less.
LEDs
The LEDs 202 may be, but are not limited to, individually-packaged LEDs, chip-on-board (“COB”) LEDs, or LED dies individually die-bonded to the conductive base 301 . The LEDs 202 may also be top-emitting LEDs, side-emitting LEDs, side view LEDs, or a combination thereof. In a preferred embodiment, LEDs 202 are side-emitting LEDs and/or side view LEDs.
The LEDs 202 are not limited to single colored LEDs. Multiple-colored LEDs may also be used. For example, if Red/Blue/Green LEDs (RGB LEDs) are used to create a pixel, combined with a variable luminance control, the colors at each pixel can combine to form a range of colors.
Mounting of LEDs onto the Conductive Base
As indicated above, LEDs 202 are mounted onto the conductive base by one of two methods, either surface mounting or LED chip bonding.
In surface mounting, as shown in FIG. 12 , the conductive base 1201 is first punched to assume any one of the embodiments discussed above, and then stamped to create an LED mounting area 1210 . The LED mounting area 1210 shown is exemplary, and other variations of the LED mounting area 1210 are possible. For example, the LED mounting area 1201 may be stamped into any shape which can hold an LED 202 .
Alternatively, the LED mounting area 1220 may not be stamped, as shown in FIG. 12B . A soldering material 1210 (e.g., liquid solder; solder cream; solder paste; and any other soldering material known in the art) or conductive epoxy is placed either manually or by a programmable assembly system in the LED mounting area 1220 , as illustrated in FIG. 12A . LEDs 202 are then placed either manually or by a programmable pick and place station on top of the soldering material 1210 or a suitable conductive epoxy. The conductive base 1201 with a plurality of LEDs 202 individually mounted on top of the soldering material 1210 will directly go into a programmable reflow chamber where the soldering material 1210 is melted or a curing oven where the conductive epoxy is cured. As a result, the LEDs 202 are bonded to the conductive base 1201 as shown in FIG. 12B .
As illustrated in FIG. 13 , LEDs 202 may be mounted onto the conductive base 1301 by LED chip bonding. The conductive base 1301 is stamped to create a LED mounting area 1330 . The LED mounting area 1330 shown in FIG. 13 is exemplary, and other variations of the LED mounting area 1330 , including stamped shapes, like the one shown in FIG. 12A , which can hold an LED, are envisioned. LEDs 202 , preferably an LED chip, are placed either manually or by a programmable LED pick place machine onto the LED mounting area 1330 . The LEDs 202 are then wire bonded onto the conductive base 1301 using a wire 1340 . It should be noted that wire bonding includes ball bonding, wedge bonding, and the like. Alternatively, LEDs 202 may be mounted onto the conductive base 301 using a conductive glue or a clamp.
It should be noted that the conductive base in the above embodiments can be twisted in an “S” shape. Then, the twisting is reversed in the opposite direction for another predetermined number of rotations; thereby, making the conductive base form a shape of a “Z”. This “S-Z” twisted conductive base is then covered by an encapsulant. With its “S-Z” twisted placement, this embodiment will have increased flexibility, as well as emit light uniformly over 360°.
In another embodiment, as shown in FIG. 11C , conductive base (e.g., conductive base 1101 ) delivering electrical current to the LEDs is wound into spirals. The spiraling process can be carried out by a conventional spiraling machine, where the conductive base is placed on a rotating table and a core 9000 passes through a hole in the center of the table. The pitch of the LED is determined by the ratio of the rotation speed and linear speed of the spiraled assembly. The core 9000 may be in any three-dimensional shape, such as a cylinder, a rectangular prism, a cube, a cone, a triangular prism, and may be made of, but not limited to, polymeric materials such as polyvinyl chloride (PVC), polystyrene, ethylene vinyl acetate (EVA), polymethylmethacrylate (PMMA) or other similar materials or, in one embodiment, elastomer materials such as silicon rubber. The core 9000 may also be solid. In one embodiment, the conductive base delivering electrical current to the LEDs is wound into spirals on a solid plastic core and then encapsulated in a transparent elastomer encapsulant.
Encapsulant
The encapsulant provides protection against environmental elements, such as water and dust, and damage due to loads placed on the integral LED light wire. The encapsulant may be flexible or rigid, and transparent, semi-transparent, opaque, and/or colored. The encapsulant may be made of, but not limited to, polymeric materials such as polyvinyl chloride (PVC), polystyrene, ethylene vinyl acetate (EVA), polymethylmethacrylate (PMMA) or other similar materials or, in one embodiment, elastomer materials such as silicon rubber.
Fabrication techniques concerning the encapsulant include, without limitation, extrusion, casting, molding, laminating, or a combination thereof. The preferred fabrication technique for the present invention is extrusion.
In addition to its protective properties, the encapsulant assists in the scattering and guiding of light in the LED light wire. As illustrated in FIG. 14 , that part of the light from the LEDs 202 which satisfies the total internal reflection condition will be reflected on the surface of the encapsulant 1403 and transmitted longitudinally along the encapsulant 1403 . Light scattering particles 1404 may be included in the encapsulant 1403 to redirect such parts of the light as shown by light path 1406 . The light scattering particles 1404 are of a size chosen for the wavelength of the light emitted from the LEDs. In a typical application, the light scattering particles 1404 have a diameter in the scale of nanometers and they can be added to the polymer either before or during the extrusion process.
The light scattering particles 1404 may also be a chemical by-product associated with the preparation of the encapsulant 1403 . Any material that has a particle size (e.g., a diameter in the scale of nanometers) which permits light to scatter in a forward direction can be a light scattering particle.
The concentration of the light scattering particles 1404 is varied by adding or removing the particles. For example, the light scattering particles 1404 may be in the form of a dopant added to the starting material(s) before or during the extrusion process. The concentration of the light scattering material 1404 within the encapsulant 1403 is influenced by the distance between LEDs, the brightness of the LEDs, and the uniformity of the light. A higher concentration of light scattering material 1404 may increase the distance between neighboring LEDs 202 within the LED light wire. The brightness of the LED light wire may be increased by employing a high concentration of light scattering material 1404 together within closer spacing of the LEDs 202 and/or using brighter LEDs 202 . The smoothness and uniformity of the light within the LED light wire can be improved by increasing the concentration of light scattering material 1404 may increase such smoothness and uniformity.
As shown in FIGS. 3 and 5 the sub-assemblies 310 and 510 are substantially at the center of the encapsulant. The sub-assemblies 310 and 510 are not limited to this location within the encapsulant. The sub-assemblies 310 and 510 may be located anywhere within the encapsulant. Additionally, the cross-sectional profile of the encapsulant is not restricted to circular or oval shapes, and may be any shape (e.g., square, rectangular, trapezoidal, star). Also, the cross-sectional profile of the encapsulant may be optimized to provide lensing for light emitted by the LEDs 202 . For example, another thin layer of encapsulant may be added outside the original encapsulant to further control the uniformity of the emitted light from the present invention.
Surface Texturing and Lensing
The surface of the integral LED light wire can be textured and/or lensed for optical effects. The integral single piece LED light wire may be coated (e.g., with a fluorescent material), or include additional layers to control the optical properties (e.g., the diffusion and consistency of illuminance) of the LED light wire. Additionally, a mask may be applied to the outside of the encapsulant to provide different textures or patterns.
Different design shapes or patterns may also be created at the surface of the encapsulant by means of hot embossing, stamping, printing and/or cutting techniques to provide special functions such as lensing, focusing, and/or scattering effects. As shown in FIGS. 15A-C , the present invention includes formal or organic shapes or patterns (e.g., dome, waves, ridges) which influences light rays 1500 to collimate ( FIG. 15A ), focus ( FIG. 15B ), or scatter/diffuse ( FIG. 15C ). The surface of the encapsulant may be textured or stamped during or following extrusion to create additional lensing. Additionally, the encapsulant 303 may be made with multiple layers of different refractive index materials in order to control the degree of diffusion.
Applications of Integrally Formed Single Piece LED Light Wire
The present invention of the integrally formed single piece LED light wire finds many lighting applications. The following are some examples such as light wires with 360° Illumination, full color light wires, and light wires with individually controlled LEDs. It should be noted that these are only some of the possible light wire applications.
The three copper wires 161 , 162 , 163 delivering electrical power to the LEDs 202 shown in FIG. 16A forming the conductive base may be wound into spirals. The LEDs are connected to the conductors by soldering, ultrasonic welding or resistance welding. Each neighboring LED can be orientated at the same angle or be orientated at different angles. For example, one LED is facing the front, the next LED is facing the top, the third LED is facing the back, and the fourth one is facing the bottom etc. Thus, the integrally formed single piece LED light wire can illuminate the whole surrounding in 360°.
An embodiment of the integrally formed single piece LED light wire is shown in FIG. 16B . As shown there are two continuous conductors corresponding to conductors 161 and 163 . Zero ohm jumpers or resistors couple conductor segments 162 to conductors 161 and 163 to provide power to LED elements 202 . As shown in FIG. 16B , the integrally formed single piece LED light wire includes a substrate. In a preferred embodiment, the substrate is flexible. In another embodiment, the single piece light wire with flexible substrate is wound about a core 9000 (see, for example, FIG. 11C ).
The integrally formed single piece LED light wire is not limited to single color. For full color application, the single color LED is replaced by an LED group consisting of four sub-LEDs in four different colors: red, blue, green, and white as shown in FIG. 17 . The intensity of each LED group (one pixel) can be controlled by adjusting the voltage applied across each sub-LED. The intensity of each LED is controlled by a circuit such as the one shown in FIG. 18 .
In FIG. 18 , L 1 , L 2 , and L 3 are the three signal wires for supplying electric powers to the four LEDs in each pixel. The color intensity of each sub-LED is controlled by a μController 6000 with the timing chart given in FIG. 19 .
As shown in FIG. 19 , because the line voltage L 2 is higher than the line voltage L 1 over the first segment of time, the red LED (R) is turned on, whereas, during the same time interval, all the other LEDs are reverse biased and hence they are turned off. Similarly, in the second time interval, L 2 is higher than L 3 thus turning on the green LED (G) and turning off all the other LEDs. The turning on/off of other LEDs in subsequent time segments follows the same reasoning.
New colors such as cold white and orange apart from the four basic ones can be obtained by mixing the appropriate basic colors over a fraction of a unit switching time. This can be achieved by programming a microprocessor built into the circuit. FIG. 20A and FIG. 20B show the timing diagrams of color rendering for cold white and orange respectively. It should be noted that the entire color spectrum can be represented by varying the timing of signals L 1 , L 2 , and L 3 .
In one embodiment of the invention, each pixel of LEDs can be controlled independently using a microprocessor circuit into the light wire as shown in FIG. 21 . Each LED module 2100 is assigned a unique address. When this address is triggered, that LED module is lit up. It will be noted that each pixel is an LED module consists of a micro-controller and three (RGB) or four (RGBW) LEDs. The LED modules are serially connected with a signal wire based on daisy chain or star bus configuration. Alternatively, the LED modules 2100 are arranged in parallel.
There are two ways to assign an address for each LED module. In a first approach, a unique address for each pixel is assigned during the manufacturing process. In a second approach, each pixel is assigned an address dynamically with its own unique address and each pixel being characterized by its own “address” periodically with trigger signal. Alternatively, the address is assigned dynamically when powered on. The dynamic addressing has the advantage of easy installation, as the integrally formed single piece LED light wire can be cut to any length. In one embodiment, the light wire can be cut into any desired length while it is powered on and functioning.
Although specific embodiments 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 may be substituted for the specific embodiments shown and described without departing from the scope of the present invention. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this invention be limited only by the claims and the equivalents thereof. | A flexible, integrally formed single piece light emitting diode (LED) light wire that provides a smooth, uniform lighting effect from all directions of the LED light wire. The integrally formed single piece LED light wire contains a conductive base comprising first and second bus elements formed from a conductive material. The bus elements distribute power from a power source to LEDs that are mounted on the first and second bus elements so that it draws power from and adds mechanical stability to the first and second bus elements. The flexible, integrally formed single piece LED light wire is assembled so that the first and second bus elements are connected to each other prior to the LED being mounted and such integrally formed single piece LED light wire is formed without a substrate. | 7 |
This invention relates to a system for the separation and storage of household recyclable waste products. More particularly, this invention relates to a recyclable storage . system for use in multi-unit buildings and residential dwellings.
BACKGROUND OF THE DISCLOSURE
With the current severe limitations on landfills for household waste products, and even their closing, many communities have turned to recycling of various materials to decrease the type and amount of waste materials that are sent to landfills. These communities now separately collect items such as newspapers and other paper products, cans, glass and plastic containers in addition to collecting general household waste products. Thus these materials must be separated by the homeowner and separately stored for pickup. Most homeowners presently do this by having a series of containers on the ground floor or garage. When loaded these containers generally must be hauled to curbside at designated times in accordance with scheduled pick ups.
Household dwellings and dwellings that are multi-level, such as condominiums, apartment houses and the like, and even homes that have kitchen areas on an upper floor, do not have convenient access to ground floor storage areas, and must separately store these items indoors, and carry them downstairs and/or through the dwelling, and to the curb. These are an added burden on the homeowner, and discourage some from complying with separation of waste materials. When several homeowners use the same facilities, such as an open outdoor storage area containing bins or dumpsters, other problems can arise, such as unpleasant odors arising from unclean containers, and wild animals and rats rummaging through the containers.
Thus a system for separating and storing waste products and recyclables without the need for separately conveying these items to remote containers, and which provides an enclosed area for storage, would be highly desirable and would encourage proper separation and storage of waste household products.
SUMMARY OF THE INVENTION
The present invention provides convenient and easy separation of household waste products that allows a homeowner access to an outside storage from the interior of a dwelling.
The present waste disposal system comprises
a) a plurality of bins mounted on a plurality of platforms fitted with a spring-loaded diverter that prevents access to said bin when in a first position and that provides access to said bin when in a second position, each diverter fitted with an operator means for changing its position in response to an electrical contact;
b) a duct leading from an opening in the interior building wall to said bins;
c) a receiving unit comprising a pivotable door that operates together with a selected diverter; and
d) a control panel mounted on an interior wall of a building having means of connecting a plurality of contact means in said control panel to each of said diverter operator means that change the position of a diverter with respect to said duct.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a side view of a system of the present invention (not to scale).
FIG. 2 is a front view of a panel useful in the present system.
FIGS. 3a and 3b are side view of alternate bins useful herein.
FIG. 4 is a schematic view of an alternate embodiment of a system of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present system will be described in detail with reference to FIG. 1. FIG. 1 is a side view of one embodiment of the system of the present invention.
A duct 11 connects a wall opening 12 mounted in the wall of a building, such as a dwelling, conveniently in the kitchen where most household waste materials are generated, to an exterior storage container 13. The storage container 13 is fitted with a plurality of platforms 16a, 16b, 16c and 16d, which can be shelves or sliders, on which a plurality of bins, 14a, 14b, 14c and 14d can be slidably supported. The bins 14 can be pulled in and out on shelves, or the platforms 16 can be a series of sliders which can engage preformed edges of the bins 14. Although the illustrated embodiment shows four sets of bins and platforms, the number can of course vary depending on the needs of the building. Alternatively, the bins 14 can be stackable, eliminating the need for shelves or sliders.
The storage container 13 has a series of diverters 20 mounted therein, each controlling or denying access to a preselected bin 14. The diverters 20a, 20b, 20c and 20d are in the form of a door fitted with a spring or hydraulic means 22, in this embodiment to maintain the diverters generally in an upright or perpendicular position with respect to the platforms 16. The diverters 20 are also fitted with operator means 18, which can be a solenoid, motor or hydraulic means that, when engaged by selection means in a wall panel 34, deflects the diverter 20 to a parallel position relative to the ground so that the top edge of the diverter 20 contacts the back wall 21 of the duct 11, thereby preventing access to others of the bins 14. Electrical means, such as wires, (not shown) connect each operator means 18a, 18b, 18c and 18d, or motor or hydraulic means, with one of the contact means 36 on the control panel 34.
FIG. 2 illustrates in detail a front view of a control panel 34 having a plurality of contact means or control buttons 36a, 36b, 36c and 36d, which may be labeled for various waste materials, such as "paper", "plastic", "cans" and the like. Each of the control buttons 36a, 36b, 36c and 36d is electrically connected to one of the operator means 18. The control panel 34 may be mounted on an interior wall of the building adjacent to the opening 12 into the duct 11 or as is convenient to the home dweller. A diverter door 38, which can conveniently be a roll top-type door, when closed, covers the wall opening 12.
FIG. 3a illustrates a suitable bin 14 having an upright back wall 50 and FIG. 3b illustrates a suitable bin having a reclining back wall 52. The exact configuration and size of the bin is not part of the invention herein but can be varied to suit the needs of each building.
The present system operates as follows: the user seeking to dispose of a particular type of waste item, opens the interior wall opening door 38, places the waste item inside and pushes the appropriate contact means 36 on the control panel 34. This contact means operates the flap of the opening 12 and the appropriate operator means 18 to deflect the appropriate one of the diverters 20 against the rear wall 21 of the duct 11. The item to be disposed of is then released down the duct 11 and, when it reaches a diverter 20, slides into the appropriate bin 14. When one of the contact means 36 is released, its corresponding operator means 18 is released and the spring means 22 brings the diverter 20 back to its original upright position.
The above description is directed to the simplest embodiment of the present invention, but additional features can be added to further enhance the convenience of the present system for the user, although generally at somewhat higher cost.
A compactor may be installed behind the door 38 through the wall leading to the duct 11 to compact the articles to be disposed of before they pass into the duct 11. This will allow more materials to be stored in each bin 14.
The bins 14 may be separable from the shelves or platforms of the storage container 13 and mounted on a wheeled platform 15 or hand truck. A handle bar (not shown) may be fitted to the front of the platform 15 for wheeling the bins to a pickup site.
Each of the diverters 20 may be fitted with a sensor which can determine when the bin 14 is full. A suitable sensor is a photoelectric cell, which breaks a circuit connected to a light on the control panel to inform a user that the particular bin 14 is full and must be emptied or replaced.
The number of bins generally will be equivalent to the number of different items that must be separated for pickup. This will vary depending on the items recycled by the community. In the event the community has commingled collection, two bins for organic matter and trash may be located in the storage container 13. This obviates the need for the diverters 20b, 20c and 20d. However, a series of bins can be used as hereinabove described, moving to a different bin when a particular bin becomes full.
FIG. 4 is a schematic view of a more complex system wherein waste products from several dwellings in a building share a common disposal duct system. A series of control panels 134 will be located in each dwelling and empty into a common duct system 111. In this embodiment, a conventional pneumatic vacuum system 125 may be placed in the bottom of the duct 111 to transport the waste materials to a bin 114, in this case located in a remote location outside the building. Such a system can connect to each of several larger bins 114, such as a 55 gallon drum or dumpster. The system of electrical control of diverters for each of the dumpsters from a control panel located in each unit and on each floor is similar to that described hereinabove. The diverters 120 are located in the lower wall of the duct leading to each container. In this case the diverter 120 is normally in a horizontal position covering each of the bins 114. The springs 122 and operator means 118, which can be a solenoid, motor or hydraulic means, operate to move the diverter upward so as to uncover the top of the bins 114 and form a wall extending from a bin 114. The pneumatic vacuum system 125 impels the waste material forward until a diverter 120 is reached which is in a position perpendicular to the bin 114, as selected by the homeowner on his control panel 134. The waste material Will then drop into the appropriate bin 114. When one of the contact means on the control panel 134 is released, its corresponding operator means 118 is also released and spring means 122 brings the diverter 120 back to its original horizontal position.
Although the present invention has been described in terms of specific embodiments, one skilled in the art will readily be able to incorporate various additional features to the system described herein. For example, although the system of the above invention has been described in terms of household waste products, it is apparent that a system as above can be installed in commercial and office buildings as well as in dwellings. These additional features are meant to be included in the present invention, which is only to be limited by the appended claims. | A waste disposal system wherein a control panel inside a building activates a series of spring loaded diverters which cooperate with a duct leading to a series of bins. Operator means is electrically connected to the control panel. When a user depresses a preselected contact means on the control panel, the diverter connected to it changes its position so as to allow access to a corresponding bin. The user can access different bins for separately storing cans, bottles, paper products, general trash and the like. The present system allows easy access to various bins, and encourages recycling by each householder. | 8 |
FIELD OF THE INVENTION
This invention relates generally to the method and apparatus for separating blood components in a blood collection device. Specifically, the invention relates to a method for the separation of the light serum portion of blood from the heavy cellular portion of blood, the blood collection device used to collect and separate the blood, and the method of manufacturing the blood collection device. More particularly, the invention relates to a method of dispensing separator gel in a blood collection tube for improving gel barrier stability and adhesion of the gel to the tube wall during the separation process.
PRIOR ART
Blood collection devices for separating the lighter serum portion of a blood sample from the heavier cellular portion thereof are well known. These devices usually comprise a collection tube containing a thixotropic gel and a contact activated clotting agent. The gel has a specific gravity intermediate the specific gravity of the serum and the cellular phases of the blood sample.
After a sample of blood has been deposited into the collection tube, the contact-activated clotting agents begin to clot the blood sample by activating clotting factors within the blood. The agent facilitates the clotting process until the blood is completely coagulated. It is essential that the agent coagulate substantially all of the blood sample in order for the subsequent serum separation process to be complete. Once the blood has coagulated, the collection tube is placed in a centrifuge to separate the lighter serum from the heavier coagulum portion. Coagulum is defined as the cellular portion and fibrin clot of the blood as opposed to the lighter serum portion of the blood. During centrifugation, the gel on the bottom of the collection tube is displaced upwardly through the blood sample until it reaches its equilibrium position at the interface between the serum and the coagulum. In this position, the gel forms a barrier between the serum and the coagulum which permits the lighter serum to be either decanted directly from the collection tube, or sampled using automated blood analyzing equipment, without interference from the coagulum.
It has long been known in the art that human blood can be readily centrifuged to effect a separation of the blood into its lighter serum and heavier coagulum portions. The specific gravity of the serum portion of human blood is between approximately 1.026 and 1.031, while the specific gravity of the coagulum portion of human blood is between approximately 1.092 and 1.095. The specific gravity of the gel is therefore chosen to be approximately between 1.032 and 1.091, so that once a blood sample is centrifuged, the gel will form an effective barrier between the serum and the coagulum. A preferred gel to be used with the method of the present invention is a thixotropic composition described in U.S. Pat. No. 4,140,631 to Okuda et al, entitled “Sealant for Separation of Serum or Plasma, and It's Use”, the entire disclosure of which is hereby incorporated by reference. As described in Okuda et al., the preferred thixotropic gel is a polymer essentially consisting of at least one compound from the group of alkyl acrylates and alkyl methacrylates, which has a specific gravity of 1.03 to 1.08 and a viscosity of about 5,000 to 1,000,000 cps at a shear rate of 1 second− 1 when measured at 25° C. However, any suitable gel-like composition which can be used as a barrier between blood portions separated in a centrifuge is felt to fall within the spirit and scope of the present invention.
This type of gel is adapted to migrate or flow from the bottom of the tube under the influence of centrifugation to the interface position between the serum and the coagulum portions of the blood and adhere to the inside surface of the collection tube wall to form a barrier between the blood portions to maintain a separation therebetween. However, this migration causes an attendant loss of gel along the tube wall, thereby requiring initial placements of larger amounts of gel in the tube in order to insure the formation of a strong enough mechanical barrier to properly separate the two portions of blood during centrifugation.
Weak adhesion of the gel to the collection tube's inner surface during centrifugation of the blood sample is a problem with prior art blood collection devices. Such weak adhesion of the gel is due to the blood sample wetting the inner surface of the blood collection device prior to the migration of the gel. This wetted inner surface inhibits the natural adhesive properties of the gel, thereby preventing the gel from forming a strong adhesive bond thereto. U.S. Pat. No. 4,257,886 seeks to overcome this deficiency by disclosing a blood separation assembly that coats the bottom portion of the collection tube with a hydrophobic material that resists wetting of the collection tube's inner surface and allows the gel to form a strong adhesive bond to the inner surface during centrifugation.
Another method of addressing the gel migration problem with its attendant loss of adhesion is found in U.S. Pat. No. 4,417,981 (hereinafter the '981 patent) which attempts to overcome the problems associated with gel migration by dispensing the gel in a separator assembly located in the central portion of the collection tube near the eventual formation of the gel barrier. The pre-placement and dispensation of the gel in a separator assembly permits the gel to quickly adhere to the tube wall during centrifugation without migration and attendant loss of gel. However, the above method of dispensing gel using a device incurs further expense in manufacturing an additional element to attain proper separation of the blood sample.
Referring to FIGS. 1-4, the prior art method of dispensing separator gel 3 and separating a blood sample into two portions is shown. The method involves utilizing a commonly known gel dispensing apparatus (not shown) to dispense a predetermined amount of gel 3 into the bottom 5 of a collection tube 2 . Contact-activated clotting powder or particles 6 are then deposited inside the collection tube 2 for eventual activation of clotting factors within blood 7 after blood 7 is added to the tube 2 .
As shown in FIG. 2, a predetermined amount 4 of blood 7 is added to the collection tube 2 and the contact clot-activating material 6 within tube 2 begins to coagulate the blood 7 before the tube 2 is placed in a centrifuge (not shown) for centrifugation of the blood 7 . The contact clot-activating material 6 promotes clot formation and includes but is not limited to glass and silica. Referring now to FIG. 3, during centrifugation of the blood 7 in the collection tube 2 , the gel 3 becomes less viscous and begins to migrate upward along the tube's 2 inner surface 8 until it reaches an interface point 9 where the lighter serum portion 10 of the blood 7 begins to separate from the heavier coagulum portion 11 . The interface point 9 is a result of the two portions of blood, serum 10 and coagulum 11 , being physically separated due to the effect of their different specific gravities during centrifugation. As shown in FIG. 4, the separation gel 3 , having a specific gravity intermediate that of the serum 10 and coagulum 11 , has migrated to the interface point 9 between the two blood portions. At the interface point 9 , the gel 3 forms a mechanical barrier 12 inside the collection tube 2 that physically separates the two blood portions and prevents the serum 10 from being contaminated by coagulum 11 .
As of yet, nothing in the prior art has addressed the problem of developing an efficient means of dispensing gel that does not suffer from either attendant loss of gel caused by migration or weak adhesive properties when the gel barrier 12 is formed.
Therefore, there exists a need in the blood collection art for an improved means of dispensing gel into a collection tube in an inexpensive and efficient manner which promotes both quick formation of the barrier separating the two blood portions and strong adhesion of the barrier to the collection tube's inner surface once the gel barrier is formed.
SUMMARY OF THE INVENTION
In brief summary, the present invention relates to a means of dispensing gel for separation of the lighter serum portion and the heavier coagulum portion of a blood sample in a blood collection tube. The preferred method of dispensing the gel comprises utilizing a gel dispensing apparatus with a nozzle head or like portion having a plurality of openings. The gel dispensing apparatus dispenses either a continuous band of gel around the central portion of the collection tube or a plurality of discrete stripes that flow to form a continuous band pattern around the central portion of the collection tube. Once the gel is so dispensed about the central portion of the collection tube, the tube is ready for accepting a blood sample for eventual separation in a centrifuge where the dispensed gel will form a barrier between the serum portion and the coagulum portion of the blood sample while exhibiting strong adhesive properties, i.e., few to no points of fluid communication between blood portions.
The present invention includes a method of dispensing gel in a tube is claimed having opposed open and closed ends, a central body portion between the opposed open and closed ends, and an interior surface formed by the central body portion and the closed end, comprising the steps of: providing the tube providing a gel dispensing apparatus for dispensing a gel into the tube, placing a portion of the apparatus inside the tube, dispensing the gel from the portion of the apparatus onto an interior wall surface formed by the central body portion, and terminating the dispensation of the gel.
The present invention further includes a blood collection device for use in separating blood into different portions comprising a tube having a central body portion, opposed closed and open ends, and an interior surface with gel dispensed on an interior wall surface thereof. Optionally, contact clot activating particles may be placed within the device.
The present invention still further includes a method of separating blood into different portions using the aforementioned blood collection device optionally containing contact clot-activating particles comprising the steps of: placing a blood sample inside the blood collection device, centrifuging the device containing the blood sample wherein centrifuging the device and the blood sample permits the gel to flow inwardly from the interior wall surface to form a barrier between the different portions of the blood sample after centrifugation is completed.
Accordingly, a principal object of the present invention is to provide an efficient and inexpensive method for dispensing gel in a collection tube for use in separating a blood sample into portions.
Another important object of the present invention is to provide an improved method of dispensing gel that requires minimal or no migration of the gel along the tube wall to form a barrier between portions of blood being separated during centrifugation.
A further object of the present invention is to provide a method of dispensing gel that forms continuous and a stable barrier in a short period of time and exhibits strong adhesive properties, i.e., few to no points of fluid communication between the blood portions.
Another important object of the present invention is to provide a means of dispensing gel in discrete stripes or a contiguous band around the interior wall surface of a collection tube.
A further object of the present invention is to provide a blood collection device that has gel dispensed on the interior wall portion of a tube.
Another principal object of the present invention is to provide a method of using a tube with gel dispensed on the inner surface thereof for separation of blood into separate portions.
Additional objects, advantages and novel features of the invention will become apparent to those skilled in the art upon examination of the following more detailed description and drawings in which like elements of the invention are similarly numbered throughout.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the prior art method of dispensing gel at the bottom of a blood collection tube;
FIG. 2 shows the prior art blood collection tube of FIG. 1 after a blood sample has been added thereto;
FIG. 3 shows the prior art migration of gel toward the serum/coagulum interface during centrifugation of the blood sample;
FIG. 4 shows the prior art blood collection tube after centrifugation of the blood sample and the formation of the gel barrier at the interface between the two portions of the blood;
FIG. 5 shows the preferred present method of dispensing gel on the interior wall portion of a collection tube using a nozzle head for dispensing gel in a contiguous band around the interior wall portion of the collection tube;
FIG. 6 shows a top section view of the blood collection tube of FIG. 5 showing the gel on the inner surface of the tube with an opening therethrough; and
FIG. 7 shows the blood collection tube of the present invention demonstrating the method of determining the lower and upper limits for dispensing gel.
FIG. 8 is a perspective view of the gel dispensing apparatus showing the alternative embodiment of a continuous opening at the nozzle head.
DETAILED DESCRIPTION
In the preferred method of dispensing gel within a blood collection tube as illustrated in FIG. 5, a blood collection device 20 , preferably a conventional collection tube 21 having an opposed open end 23 and closed end 34 is made of a material which is non-interactive with the blood 35 , such as but not limited to plastic, glass, plastic-lined glass or glass-lined plastic. The collection tube 21 has separator gel 22 which is a thixotropic substance dispensed into the central portion of tube 21 between opposed open end 23 and closed end 34 prior to adding a blood sample 35 . Gel 22 is placed within the tube 21 by using a positive displacement metering apparatus 24 that uses a nozzle head 25 for dispensing a gel or the like. The nozzle head 25 includes one or more openings but preferably a plurality of openings 26 located at its free distal end 31 . If one opening is provided at the free distal end 31 , the opening is preferably a continuous opening around the periphery of an exterior surface 35 of nozzle head 25 as illustrated in FIG. 8 . Although one or more openings 26 can be utilized for the present invention, the preferred embodiment having a plurality of openings 26 will be exemplified throughout the remainder of this description for purposes of simplicity only. The plurality of openings 26 dispense the gel 22 onto the inner surface 29 of the tube 21 in discrete stripes 30 that flow to form a circumferential band pattern around tube 21 . Preferably, the gel 22 is dispensed in discrete stripes 30 , although any suitable configuration that ultimately flows to form one or more continuous bands 30 around the inner surface 29 of the collection tube 21 is felt to fall within the spirit and scope of the present invention.
Prior to dispensing gel 22 , the nozzle head 25 is placed inside the collection tube 21 such that openings 26 are positioned at a predetermined lower point 27 to begin dispensing gel 22 along the inner wall surface 29 of tube 21 . As gel 22 is dispensed through openings 26 , the tube 21 is slowly drawn downward so as to move closed end 34 away from the nozzle head 25 until the openings 26 reach a predetermined upper limit 28 near open end 23 . As the dispensing procedure is about to terminate, the nozzle head 25 is slightly ahead of the gel 22 flow, thereby forming a discontinuous circumferential pattern 32 at the predetermined upper limit 28 . In the preferred method of dispensation with a plurality of openings 26 , the discontinuous circumferential pattern 32 formed at the end of dispensation is a crown shape design, but any suitable pattern 32 may be made. Once the dispensation of the gel 22 is terminated, the gel 22 flows and adheres to the inner surface 29 forming a concentric band 30 around the central portion of tube 21 between the predetermined upper and lower limits, 28 and 27 respectively. As better seen in FIG. 6, the gel 22 , after flow thereof has ceased, forms a concentric band 30 with the discontinuous pattern 32 at the top of band 30 and an opening 33 through which the blood sample 35 may initially pass before centrifugation and formation of the gel barrier. After the gel 22 has set or flow has ceased, the collection device 20 is ready for the blood sample 35 to be added for centrifugation and separation as described above.
The location of the upper and lower limits, 28 and 27 respectively, in dispensing gel 22 to form a concentric band on the inner surface 29 of the collection tube 21 depends on the size of the tube 21 being utilized and the volume of the blood sample 35 to be added to the tube 21 . Referring to FIG. 7, a general formula for determining the upper and lower limits, 28 and 27 respectively, for gel 22 dispensation will be discussed. X is a variable that represents the volume of the blood sample 35 added to the collection tube 21 prior to centrifugation. In determining the lower and upper limits for gel placement, 27 and 28 respectively, variable X is multiplied by predetermined constants, C LL for the lower limit 27 and C UL for the upper limit 28 . These constants are established by one skilled in the art based on the for a particular size of the tube 20 and the particular gel configuration desired. The formulas used are shown below:
lower limit 27 = X ·C LL
upper limit 28 = X ·C UL
For example if C LL and C UL are established as being 0.7 and 0.31 respectively for a particular tube to achieve a particular desired configuration, the lower and upper limits, 27 and 28 , respectively, may be easily determined by knowing the volume of the drawn blood sample 35 added to the collection tube 20 . To illustrate, if a blood sample 35 having a volume of 100 mm is added to the collection tube 21 , the lower limit 27 for dispensing gel 22 would be 70 mm and the upper limit 28 would be 31 mm as set forth below.
lower limit 27 =100 mm×0.7=70 mm
upper limit 28 =100 mm×0.31=31 mm
Thus, the gel 22 would be dispensed between a range of 31 mm to 70 mm from the open end 23 to form a band 30 . It should be noted that the formula would be varied accordingly if more than one band 30 would be desired for further separation techniques known in the art.
The above example is used for the purpose of illustrating the upper and lower limits, 28 and 27 respectively, for dispensing gel 22 in a collection tube 21 made according to the preferred embodiment of the present invention. The above formula insures that a firm mechanical gel barrier is formed after centrifugation regardless of the type of centrifuge used to separate the blood sample 35 .
The preferred method of dispensing gel 22 as described above has the advantage of limited migration of the gel 22 during centrifugation while promoting a stronger mechanical barrier after centrifugation. Moreover, dispensing gel 22 on the interior wall portion between upper and lower limits, 28 and 27 respectively, of collection tube 21 has the further advantage of requiring less gel 22 than required in prior art methods in which gel 22 migration was utilized. For example, prior art methods for dispensing gel 22 dispense approximately 2.2 grams of gel 22 to form a sufficient barrier after centrifugation of the blood sample 35 while the present invention requires approximately 1.4 grams of gel 22 to form the same strong barrier. Thus the present invention requires approximately 36% less gel 22 which creates a significant cost savings.
Finally, the method of separating a blood sample 35 into different portions using the blood collection device 20 of the present invention will be discussed. The method of separating a blood sample 35 using the blood collection device 20 having contact clot-activating particles 6 previously deposited inside device 20 comprises the first step of providing a blood sample 35 inside the device 20 . After the blood sample 35 is deposited, the sample 35 is then centrifuged, wherein centrifuging the blood sample 35 permits the gel 22 to flow inwardly as the blood sample 35 travels through the opening 33 until a barrier is formed between the different phases of the blood sample 35 once centrifugation is complete.
The blood collection device 20 of the present invention may likewise optionally contain contact clot-activating particles such as but not limited to carbon, silica, fumed silica, glass and the like. Likewise, the entire interior surface or a portion of the interior surface of the blood collection tube 21 of the present invention may optionally be sprayed with a water and/or silica mixture to prevent blood from sticking to the sides of the tube. This spray is preferably applied before dispensing of the gel 22 as described above.
Optionally, the interior of the blood collection device 20 of the present invention may be sprayed with an ethylene copolymer such as but not limited to polyethylene oxide and/or polydimethyl siloxane to promote gel 22 binding to the wall.
Although particular embodiments of the invention have been shown, it is not intended that the invention be limited thereby, instead the scope of the present invention is intended to be limited by the appended claims. | A method of dispensing gel for separation of the serum and coagulum portions of a blood sample in a blood collection tube is disclosed. The present invention of dispensing the gel preferably comprises utilizing a gel dispensing apparatus with a nozzle head having a plurality of openings. The gel dispensing apparatus dispenses either a continuous band of gel around the central portion of the collection tube or a plurality of discrete stripes that forms a circumferential pattern thereto. Once the gel is dispensed, the tube is ready for accepting a blood sample for eventual separation in a centrifuge where the dispensed gel will form a barrier that exhibits strong adhesive properties after separation of the blood sample has occurred. | 1 |
Botanical/commercial classification: Rosa hybrida /Shrub Rose Plant.
Varietal denomination: cv. Meiklutz.
SUMMARY OF THE INVENTION
The new variety of Rosa hybrida shrub rose plant was created by artificial pollination wherein two parents were crossed which previously had been studied in the hope that they would contribute the desired characteristics. The female parent (i.e., the seed parent) was the product of the cross of the ‘Noatraum’ variety (U.S. Plant Pat. No. 7,282) and an unnamed seedling (non-patented in the United States). The ‘Noatraum’ variety is marketed under the FLOWER CARPET Pink Trademark. The male parent (i.e., the pollen parent) was ‘The Fairy’ variety (non-patented in the United States).
(‘Noatraum’×Unnamed Seedling)בThe Fairy’.
The seeds resulting from the above pollination were sown and small plants were obtained which were physically and biologically different from each other. Selective study resulted in the identification of a single plant of the new variety.
It was found that the new Shrub rose plant of the present invention:
(a) exhibits a bushy and compact growth habit, (b) forms in abundance attractive small cup-shaped pink blossoms, (c) displays rather dense semi-glossy green foliage, (d) exhibits excellent tolerance to diseases particularly with respect to Marsonina rosea, and (e) is particularly well suited for growing as attractive ornamentation in the landscape.
The new variety well meets the needs of the horticultural industry and can be grown to advantage as attractive ornamentation in parks and gardens.
The new variety can be readily distinguished from its ancestors. For instance, the blossom appearance is considerably different from that of the ‘Noatraum’ and ‘The Fairy’ varieties. More specifically, the ‘Noatraum’ blossoms are larger and are darker pink in coloration. The blossoms of ‘The Fairy’ variety are lighter pink in coloration.
The new variety has been found to undergo asexual propagation in France by a number of routes, including budding, grafting, and the use of cuttings. Asexual propagation by the above-mentioned techniques in France has shown that the characteristics of the new variety are stable and are strictly transmissible by such asexual propagation from one generation to another.
The new variety has been named ‘Meiklutz’.
BRIEF DESCRIPTION OF THE PHOTOGRAPH
The accompanying photograph shows as nearly true as it is reasonably possible to make the same, in a color illustration of this character, typical specimens of the plant parts of the new variety. The rose plants of the new variety were approximately one year of age and were observed during June while growing on Rosa froebelli understock outdoors at Le Cannet des Maures, Var, France. Dimensions in centimeters and a standard color presentation are indicated at the bottom of the photograph.
FIG. 1 — illustrates a specimen of a young shoot;
FIG. 2 — illustrates a specimen of a floral bud before the opening of the sepals;
FIG. 3 — illustrates a specimen of a floral bud at the opening of the sepals;
FIG. 4 — illustrates a specimen of a floral bud at the opening of the petals;
FIG. 5 — illustrates a specimen of a flower in the course of opening;
FIG. 6 — illustrates a specimen of an open flower — plan view — obverse;
FIG. 7 — illustrates a specimen of an open flower — plan view — reverse;
FIG. 8 — illustrates a specimen of a fully open flower — plan view — obverse;
FIG. 9 — illustrates a specimen of a fully open flower — plan view — reverse;
FIG. 10 — illustrates a specimen of a floral receptacle showing the arrangement of the stamens and pistils;
FIG. 11 — illustrates a specimen of a floral receptacle showing the arrangement of the pistils (stamens removed);
FIG. 12 — illustrates a specimen of a flowering stem;
FIG. 13 — illustrates a specimen of a main branch;
FIG. 14 — illustrates a specimen of a leaf with three leaflets — plan view — upper surface;
FIG. 15 — illustrates a specimen of a leaf with five leaflets — plan view — under surface;
FIG. 16 — illustrates a specimen of a leaf with seven leaflets — plan view — upper surface; and
FIG. 17 — illustrates a cluster of buds in various stages of opening together with an open flower.
DETAILED DESCRIPTION
The chart used in the identification of the colors is that of The Royal Horticultural Society (R.H.S. Colour Chart). The description is based on the observation of one-year-old plants during May while budded on Rosa froebelli understock and growing in greenhouses at Le Cannet des Maures, Var, France.
Class: Landscape Shrub Rose. Plant:
Habit. —Bushy.
Branches:
Color. —Young stems: near Yellow-Green Group 144B. Adult wood: near Green Group 143A. Thorns. —On young stems: Small prickles: Quantity: none. Long prickles: Configuration: upright and longish pointed, and slightly concave on the under surface with a narrow and long base. Quantity: approximately 7 on average on a stem length of 10 cm. Length: approximately 0.7 cm on average. Color near Greyed-Orange Group 164A. On adult stems: Small prickles: Quantity: none Long prickles: Configuration: upright and longish pointed, and slightly concave on the under surface with a narrow and long base. Quantity: approximately 8 on average on a stem length of 10 cm. Length: approximately 0.8 cm on average. Color near Greyed-Orange Group 177A.
Leaves:
Stipules. —Smooth, adnate, pectinate, rather broad, approximately 1.4 cm in length on average, approximately 0.6 cm in width on average, near Green Group 141B on the upper surface, and near Green Group 143B on the under surface. Petioles. —Upper surface: near Yellow-Green Group 144A in coloration. Under surface: near Green Group 143B in coloration. Texture: smooth, non-glandular and without prickles on the upper and under surfaces. Length: approximately 1.7 cm for the terminal leaflet. Rachis. —Upper surface: near Green Group 139C in coloration. Under surface: near Green Group 143B in coloration. Texture: smooth. Leaflets. —Number 3, and most often 5 and 7. Shape: generally oval with a somewhat rounded tip and a rounded base. Size: the terminal leaflets commonly are approximately 3.9 cm in length. Serration: small and single (as illustrated). Texture: somewhat flexible. General appearance: rather dense with a semi-glossy aspect. Color (young foliage): upper surface: near Green Group 141A. Under surface: near Yellow-Green Group 146C. Color (adult foliage): Upper surface: near Green Group 139A. Under surface: near Yellow-Green Group 146B.
Inflorescence:
Number of flowers. —Commonly pluriflorous, with a plurality of blossoms per stem. Peduncle. —Tomentose, approximately 1.5 cm in length on average, approximately 0.2 cm in diameter on average, and near Greyed-Purple Group 183A in coloration. Sepals. —Upper surface: smooth and near Green Group 138B. Under surface: smooth and near Green Group 141B in coloration. Shape: longish and narrow, and tend to be upright at the base. Size: near 1.4 cm in length on average, and near 0.3 cm in width at the widest point on average. Buds. —Shape: elongated. Size: small. Length: approximately 1.4 cm on average. Width: near 1 cm on average at the widest point. Color as the calyx breaks. Upper surface: near Red Group 55A, and suffused with Red Group 55B. Under surface: near Red Group 56A, and amply suffused with near Red Group 55A and 55B. Flower. —Shape: cup-shaped. Diameter approximately 2.2 cm on average. Color (in the course of opening): Upper surface: near Red-Purple Group 62A, and amply suffused with near Red Group 55A. Under surface: near Red-Purple Group 62D, and suffused with near Red-Purple Group 62B. Spot at base: very small and near Green-White Group 157D on the upper surface and near White Group 155D on the under surface. Color (when fully open): Upper surface: near Red-Purple Group 62A suffused with near Red-Purple Group 57C. Under surface: near Red-Purple Group 56D suffused with near Red Group 55C, and amply suffused with near Red Group 55B. Spot at base: very small and near Green-White Group 157D on the upper surface and near White Group 155D on the under surface. Fragrance: none. Petal number: commonly approximately 10 to 16 on average under normal growing conditions. Petal shape: with a substantially rounded tip and base. Petal texture: relatively thick. Petal length: approximately 1.7 cm on average. Petal width: approximately 1.6 cm on average. Petal arrangement: imbricated; and commonly with petaloids towards the center. Petal drop: good with the petals commonly detaching cleanly before drying. Stamen number approximately 93 on average. Anthers: regularly arranged around the styles, approximately 0.1 cm in size on average, and near Yellow-Orange Group 23B in coloration. Pollen: present. Filaments: approximately 0.3 cm in length on average and near Yellow Group 2C in coloration. Pistils: approximately 30 on average. Stigmas: approximately 0.1 cm in Size on average and near Yellow Group 2C in coloration. Styles: approximately 0.4 cm in length on average, and near Green-Yellow Group 1C in coloration. Receptacle: tomentose, approximately 0.5 cm in length on average, approximately 0.4 cm in width on average at the widest point, and near Greyed-Purple Group 183B in coloration.
Development:
Vegetation. —Strong. Blooming. —Late, very abundant, and recurrent. Tolerance to diseases. —Very good, particularly with respect to Marsonina rosae. | A new and distinct variety of Shrub Rose plant is provided that abundantly forms attractive small cup-shaped pink blossoms. A bushy and compact growth habit is displayed and the foliage is rather dense and semi-glossy. The disease tolerance is good particularly with respect to Marsonina rosea. The plant is well suited for providing attractive ornamentation in the landscape, such as in parks and gardens. | 0 |
RELATED APPLICATIONS
[0001] This application claims priority to International patent Application No. PCT/US2010/023777, International Filing Date 10 Feb. 2010, entitled Flexible Anti-Collapsible Catheter Sleeve, which claims priority to U.S. patent application Ser. No. 12/431,631 filed Apr. 28, 2009 entitled Flexible Anti-Collapsible Catheter Sleeve (now abandoned), which claims priority to U.S. Provisional Application Ser. No. 61/151,415 filed Feb. 10, 2009 entitled Flexible Anti-Collapse Catheter Sleeve, all of which are hereby incorporated herein by reference in their entireties.
BACKGROUND OF THE INVENTION
[0002] Ventricular catheters are typically used for monitoring pressure and draining fluid (e.g., cerebrospinal fluid) in mammalian bodies, an example of which is seen in U.S. Pat. No. 6,673,022, the contents of which are incorporated by reference. Hence, these catheters typically have one or more passages within them to allow for drainage, air communication, wires or other components.
[0003] The ventricular catheter for intracranial use is typically fixed in place with a bolt and compression fitting. One end of the bolt is screwed into or otherwise fixed in the skull of a patient and the other end of the bolt connects to the compression fitting. Once the catheter has been placed in the brain, the compression fitting is tightened to fix the location of the catheter relative to the bolt to prevent axial movement of the catheter within the patient. Since the compression fitting applies pressure to a portion of the catheter, an exoskeleton or similar rigid support structure must be placed over any portion of the catheter that may be contacted by the compression element. This exoskeleton or rigid support structure prevents the catheter's lumen (e.g., such as a drainage lumen) from collapsing.
[0004] Previous exoskeleton designs have employed a rigid sleeve or support tube fixed over that portion of the catheter that may be subjected to the force of the compression fitting. This rigid sleeve prevents collapse of the catheter lumens but also remains relatively unbendable. In this respect, the rigid tube maintains the orientation of the catheter in line with the axis of the passage through the bolt and compression fittings. Since the length that the catheter that must be advanced into the brain varies from person to person, the rigid tube must be long enough to accommodate these various catheter positions. Hence, the rigid tube causes at least a portion of the catheter to rigidly stick up from the bolt and compression fitting.
[0005] In some arrangements of this system, the bolt, fitting and catheter can rigidly extend away from the patient for some distance. For example, the bolt and fitting may extend above the scalp about 1.5 inches while the rigid tube extends above the bolt by another 1 inch.
[0006] This combined length of the bolt, the fitting and the rigid tube is problematic for at least two reasons. First, it increases the likelihood that the assembly will be inadvertently hit. For example, the catheter provides a longer and more rigid area for a nurse or agitated patient to contact.
[0007] Second, the length of the tube increases the length of the lever arm which conveys torque to the skull. In this respect, the force of contact from the rigid tube is much greater than it would be against the bolt alone. In some cases, the torque increase allows even a relatively minor force to pop out the bolt from the skull, causing serious complications.
[0008] In addition to torque forces, the increased area of the rigid tube may increase the likelihood of applying downward, axial force on the catheter. This force may overcome the holding force of the compression fitting, pushing the catheter into the patient's brain and likely causing damage.
SUMMARY OF THE INVENTION
[0009] According to a preferred embodiment of the present invention, an exoskeleton consisting of a thin-walled spiral-cut sleeve or series of rings is placed on a portion of a ventricular catheter that may be moved into the compression fitting (or similar securing mechanism) of a bolt in a patient. The exoskeleton prevents the compression fitting from collapsing the lumens (e.g., the drainage lumen) of the catheter. Spacing between the rigid areas (such as a spiral cut) allows the exoskeleton to flex axially so that the catheter can bend freely. The flexibility of the exoskeleton lowers the profile of the system and precludes the possibility that a downward force on the catheter will push the catheter into the brain.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] These and other aspects, features and advantages of which embodiments of the invention are capable of will be apparent and elucidated from the following description of embodiments of the present invention, reference being made to the accompanying drawings, in which
[0011] FIG. 1 illustrates a catheter and exoskeleton according to the present invention;
[0012] FIG. 2 illustrates the catheter and exoskeleton of FIG. 1 with a bolt and compression fitting;
[0013] FIG. 3 illustrates a magnified cross sectional view of the compression fitting from FIG. 2 ;
[0014] FIG. 4 illustrates the catheter, exoskeleton, bolt and compression fitting of FIG. 2 ;
[0015] FIG. 5 illustrates the exoskeleton of FIG. 1 ;
[0016] FIG. 6 illustrates the exoskeleton of FIG. 5 in a bent configuration; and
[0017] FIG. 7 illustrates an exoskeleton according to the present invention.
DESCRIPTION OF EMBODIMENTS
[0018] Specific embodiments of the invention will now be described with reference to the accompanying drawings. This invention may, however, 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 be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. The terminology used in the detailed description of the embodiments illustrated in the accompanying drawings is not intended to be limiting of the invention. In the drawings, like numbers refer to like elements.
[0019] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
[0020] FIGS. 1 and 2 illustrates a catheter 100 having a flexible exoskeleton 102 that allows the catheter 100 to freely bend while preventing the interior contents of the catheter 100 from being crushed by a fastening mechanism such as a compression fitting 114 . The exoskeleton 102 reduces the height and therefore the torque that forces (such as accidental contact) can exert on the bolt 116 . Hence, the risk of popping out the bolt 116 from, for example, the patient's skull, is greatly reduced.
[0021] Preferably, the exoskeleton 102 can be an integral part of the catheter 100 by, for example, adhesive bonding.
[0022] As seen in the present example, a distal section 106 of the catheter 100 includes a plurality of drainage apertures which connect to a drainage passage within the catheter 100 . The catheter 100 preferably includes a pressure sensor 104 for measuring a pressure within a patient. A tube 108 within which the pressure signal is conveyed, splits off from the catheter 100 at splitter 112 . The proximal end of the catheter is terminated in a luer fitting 110 . The luer fitting is connected to a standard drainage bag system (not shown).
[0023] As best seen in FIG. 2 , the exoskeleton 102 is located along a length of the catheter 100 where a compression fitting 114 or similar position fixing mechanism may press against or otherwise compress the catheter 100 . Since different patients and different insertion locations may require the catheter 100 to be inserted to different depths, the flexible region extends along much of the length of the catheter 100 . Preferably, this exoskeleton 102 length is about 4 inches.
[0024] FIG. 4 illustrates the exoskeleton 102 and catheter 100 in a bent or flexed position proximal to the bolt 116 and compression fitting 114 . As compared with the non-flexed position in FIG. 2 , the exoskeleton 102 reduces torque-amplified forces on the bolt 116 and compression fitting 114 (coupled to the bolt 116 ) that would otherwise be present if the exoskeleton 102 was non-flexible (as in the prior art).
[0025] FIG. 3 illustrates a magnified view of a typical compression fitting 114 . As the upper portion 120 is screwed onto the lower portion 122 , an inner member 119 presses down on a compression element 118 . As the compression element 118 is compressed or squeezed downwards, it expands outward against the exoskeleton 102 of the catheter 100 . Additionally, a set screw 124 can be further used to further secure the exoskeleton 102 from axial movement.
[0026] As previously discussed, prior art exoskeletons are rigid, especially along the length that is squeezed or pressed on by the compression fitting 114 . This leaves the prior art exoskeletons unable to bend. However, the exoskeleton 102 resists crushing while allowing flexibility (i.e., axial flexibility along a length of said exoskeleton 102 ) by preferably includes a plurality of rigid sections or areas that are interspersed with non-rigid areas or even no material. These rigid sections can be connected together as a unitary rigid element or can be distinct from each other. The rigid sections are arranged along the length of the exoskeleton 102 to withstand being crushed by a radial force typically generated by a compression fitting 114 . Spaces between the rigid sections allow the exoskeleton 102 to flex as needed.
[0027] FIGS. 5 and 6 best show a preferred embodiment of the flexible exoskeleton 102 , including a spiral cut 102 A forming a generally larger spiral of rigid material 102 B. This spiral cut 102 A introduces axial flexibility into the exoskeleton 102 while retaining much of the strength along the diameter to resist crushing under pressure from the compression fitting 114 .
[0028] The width of the rigid material 102 B can be varied to increase or decrease the crush resistance and flexibility of the exoskeleton 102 . Generally, the flexibility can be increased and the crush resistance can be decreased by increasing the number of turns in the spiral cut 102 A. Conversely, the crush resistance can be increased and the flexibility can be decreased by decreasing the number of turns in the spiral cut 102 A. Preferably, the flexible section 102 sized to fit an 8 French catheter is composed of a rigid material such as polyimide with a thickness of about 0.006″. The spiral cut 102 A is preferably about 0.01″ wide and forms about 10 turns per inch.
[0029] Preferably, the exoskeleton 102 can be formed by cutting the spiral cut 102 A into the tube via a laser or mechanical cutting device. Alternately, this spiral shape can be preformed by molding techniques.
[0030] While a spiral cut 102 A has been described, it should be understood that other cut shapes are contemplated within the present invention. For example, right angle cuts forming a stair pattern, a spiral wave pattern, a circumferential wave pattern, or similar variations on these patterns.
[0031] FIG. 7 illustrates another preferred embodiment of an exoskeleton 130 that includes a plurality of rigid rings 130 (some of which are shown cross sectioned in this figure) which are fixed in place by a flexible tube 130 B. The rings 130 are preferably composed of a rigid polyimide or metal and are preferably adhered or embedded within the flexible tube 130 B. The flexible tube 130 B is preferably composed of a flexible plastic. Alternately, the rings 130 may be only connected by a plurality of longitudinal wires connected to the inner or outer diameter of the rings 130 A or may simply be adhered to the exterior of the catheter 100 in a evenly spaced arrangement.
[0032] Although the invention has been described in terms of particular embodiments and applications, one of ordinary skill in the art, in light of this teaching, can generate additional embodiments and modifications without departing from the spirit of or exceeding the scope of the claimed invention. Accordingly, it is to be understood that the drawings and descriptions herein are proffered by way of example to facilitate comprehension of the invention and should not be construed to limit the scope thereof. | A thin-walled, spiral-cut sleeve is placed on a portion of a ventricular catheter that may be moved into the compression fitting (or similar securing mechanism) of a bolt in a patient. The wall of the sleeve is sufficiently thick so as to prevent the compression fitting from collapsing the drainage lumen of the catheter. A spiral cut in the sleeve allows the sleeve to flex axially, reducing torque forces on the bolt. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Application No. 61/662,327, filed Jun. 20, 2012, which is hereby incorporated by reference herein in its entirety.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] The invention was made with government support under Grant No. 1041895 awarded by the National Science Foundation. The government has certain rights in the invention.
TECHNICAL FIELD
[0003] The disclosed subject matter relates to methods and systems for using Subsurface Laser Engraving (SSLE) to create one or more wafers from a material.
BACKGROUND
[0004] Silicon solar cells comprise 80% of the worldwide production of photovoltaics (PV) and almost all of this production occurs on watered substrates. Wafers are typically created by slicing blocks of silicon using a wire dicing saw which can not only cause a large amount of the silicon to be wasted, but also uses a cutting fluid that coats the silicon and subsequently needs to be removed.
[0005] Other methods for creating wafers, including directly depositing thin silicon layers, cleaving thin substrates, and producing kerfless slices of silicon from an ingot via ion implantation also have limitations.
[0006] Accordingly, new processes for producing silicon wafers are desirable.
SUMMARY
[0007] Methods and systems for using SSLE to create one or more wafers from a material are provided. In accordance with some embodiments, a method for using SSLE to create one or more wafers from a material is provided, the method comprising: using a laser light beam to etch pits in the material to create one or more layers of etch pits in a subsurface of the material; and dividing the material into one or more individual wafers with a subsequent etch.
[0008] In accordance with some embodiments, the laser light beam has a wavelength between about 1 μm and about 2 μm.
[0009] In accordance with some embodiments, the material is transparent to the laser light beam at some intensities and absorbs energy from the laser light beam at other intensities.
[0010] In accordance with some embodiments, the laser light beam has an intensity over 1×10 6 W/cm 2 .
[0011] In accordance with some embodiments, the one or more wafers are cut to a thickness between about 10 μm to about 200 μm.
[0012] In accordance with some embodiments, the laser creates etch pits between about 10 microns to about 1 mm apart.
[0013] In accordance with some embodiments, a system for using SSLE to create one or more wafers from a material is provided, the system comprising: a controller for controlling the position of a focal point of a laser light beam with respect to the material and causing an irradiation of the laser light beam at a plurality of focal points; and an etch for splitting the material into the one or more wafers based on the plurality of focal points.
[0014] In accordance with some embodiments, the laser light beam has a wavelength of between about 1 μm to about 2 μm.
[0015] In accordance with some embodiments, the material is transparent to the laser light beam at some intensities and absorbs the laser light beam at other intensities.
[0016] In accordance with some embodiments, the laser light beam has an intensity over 1×10 6 W/cm 2 .
[0017] In accordance with some embodiments, the controller causes the plurality of focal points to define wafers with thicknesses between about 10 μm to about 200 μm.
[0018] In accordance with some embodiments, the controller causes the laser light beam to create etch pits between about 10 microns to about 1 mm apart.
[0019] In accordance with some embodiments, the controller causes the laser light beam to create etch pits at more than one depth within a material, for example, through the use of different power levels and/or wavelengths and/or different focal lengths, and/or using multiple scans across a wafer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 shows pits in a silicon block which can occur at the focal point of a laser in accordance with some embodiments.
[0021] FIG. 2 is a graph showing Absorption A (%) versus Laser-Intensity (I s ) for a laser light beam in accordance with some embodiments.
[0022] FIG. 3 is a graph showing Transmission (ratio) versus Optical intensity, W/cm 2 , for an Er-YAG laser and a Ho-YAG laser in accordance with some embodiments.
[0023] FIG. 4 shows a laser light beam with subsurface focal point cutting a silicon block into one or more wafers in accordance with some embodiments.
[0024] FIG. 5 shows hardware which can be used to control the positioning and focal depth of a laser light beam in accordance with some embodiments.
[0025] FIG. 6 is a flow diagram of a process for controlling the positioning and focal depth of a laser light beam in accordance with some embodiments.
DETAILED DESCRIPTION
[0026] Methods and systems for using SSLE to create one or more wafers from a material are provided.
[0027] Turning to FIG. 1 , in accordance with some embodiments, SSLE can occur by focusing laser light beam 102 within the bulk of an optically transparent material 104 such as silicon. Material 104 can be transparent to the wavelength of laser light beam 102 . The intensity of laser light beam 102 at its focal point can be high, which can cause absorption over a small area. As shown in FIG. 1 , this absorption can produce a small defect that may appear as a pit 106 in material 104 while leaving the rest of material 104 undamaged. By scanning laser light beam 102 across the surface of a material, such as silicon, as well as varying the focal depth, a 3D array of pits 106 can be created within the material.
[0028] Rather than completely cutting through each layer of material 104 , small etch pits 106 can be created which can result in layers of weakened material that can then be etched in an anisotropic etch, such as potassium hydroxide (KOH) for silicon materials or any other suitable etch. For example, a silicon block which has been scanned by laser light beam 102 to create a 3D array of pits 106 can be submerged in a container of liquid KOH. The KOH can then etch the silicon at different rates depending on the crystalline plane of the silicon created by laser light beam 102 . For other materials, other anisotropic etchants are known and can be used. For example. Gallium Arsenide may be etched using a hydrochloric acid based etching solution.
[0029] In accordance with some embodiments, laser light beam 102 and semiconductor material requirements can vary. A variety of laser light beams can be used, such as green, infrared, and/or any other suitable wavelength of laser light beam. A multi-wavelength laser light beam can also be used. One or more of these laser light beams can be used with one or more materials, such as silicon, germanium, silicon carbide, III-V compound semiconductor materials including but not limited to GaAs and InP, II-VI compound semiconductor materials including but not limited to CdTe, glass, crystal gemstones, acrylic, and/or any other suitable material.
[0030] Material 104 can be transparent to laser light beam 102 under some intensities and can absorb laser light beam 102 at other intensities. FIG. 2 is a graph showing Absorption A (%) versus Laser-Intensity (I s ) for a laser light beam and water material in accordance with some embodiments. As shown in FIG. 2 , material 104 can be transparent to the laser light within a first range of intensities (area 202 ), and material 104 can absorb the laser light at a second range of intensities (area 204 ). A transition 206 between these areas can constitute a threshold intensity. Silicon, for example, has a threshold intensity (I s ) at 10 6 W/cm 2 , as shown, for example, in FIG. 3 .
[0031] The threshold intensity can be a point or range of intensities above which laser light beam 102 is absorbed and below which the semiconductor is transparent. For example, a GaAs (Gallium Arsenide) wafer has a band gap of 1.43 eV (electron volt) and can be cut using a laser with a wavelength of more than 900 nm (nanometer). Tuning the wavelength of the laser can optimize the quality of the cleaved layer.
[0032] Material 104 can be matched with SSLE, which can require a non-linear absorption coefficient and a Q-switched laser. A semiconductor such as silicon has a known non-linearity which can be caused by carrier absorption and two-photon processes. There are a variety of lasers with wavelengths between about 1 μm to about 2 μm that can be used in some embodiments (e.g., Silicon waters). For example, a Ho-YAG laser with a wavelength of 2.09 μm exhibits a transition to absorption in Silicon at an optical intensity of 10 6 W/cm 2 as shown in FIG. 3 . Therefore, tuning the wavelength of laser light can adjust the absorption of laser light by the semiconductor. In the case of silicon, the absorption coefficient of silicon, as an indirect bandgap semiconductor, has a long tail. Silicon can absorb laser light at wavelengths between about 1200 nm and about 3000 nm. Other wavelengths of light can be used for other materials
[0033] For example, a laser light beam with a wavelength between about 1 μm to about 2 μm can ablate a series of etch pits beneath a surface of the silicon several centimeters down. The layers of silicon can be cut to a thickness between about 10 μm to about 200 μm with kerf losses limited by the focus of the laser beam (e.g., 20 μm).
[0034] Scanning laser light beam 102 across the surface and varying the focal depth can produce a 3D array of pits 400 within a block of material, as shown in silicon block 402 in FIG. 4 . Additionally, scanning from the bottom to the top can focus laser light beam 102 on the succession of layers. The entire block of the material can be patterned with laser light beam 102 in some embodiments.
[0035] FIG. 5 shows hardware 500 which can be used to pattern a block of material by controlling the position and focal depth of a laser 502 . A user can input parameters into controller 504 which can define the thickness and size of the wafers to be cut by laser 502 . These parameters can be entered such that by scanning laser 502 across the surface of a block of material, as well as varying the focal depth, an array of pits can be created within block of material.
[0036] For example, a parameter can be entered which defines the thickness of a wafer. The thickness can be the distance between layers in z-axis 404 , as shown in FIG. 4 . Tuning the wavelength of laser 502 can alter the amount of laser light which can be absorbed by the material.
[0037] Furthermore, parameters can be entered which can define the size of a wafer. For example, parameters can be entered which can define a width in x-axis 406 and a length in y-axis 408 as shown in FIG. 4 . Additionally, parameters can be entered which can be used to scan laser 502 across the block of material a certain width and length and can create etch pits in the block of material a specified distance apart.
[0038] Based on one or more parameters entered into controller 504 , for width, length, and depth, a signal can be sent to drivers 506 , 508 , and 510 , respectively. Drivers 506 , 508 , and 510 can then amplify the signals to move x servo 512 , y servo 514 , and z servo 516 to the appropriate width, length, and focal depth. Controller 504 can then send a signal to trigger laser 502 .
[0039] FIG. 6 is a flow diagram of a process for controlling the positioning and focal depth of a laser in accordance with some embodiments. Any suitable mechanism for controlling the positioning and focal depth of a laser can be used in some embodiments. For example, a process such as process 600 of FIG. 6 can be implemented by hardware 500 to control the position and focal depth of a laser in some embodiments.
[0040] For example, a set of parameters can be entered at controller 504 which can cause laser 502 to scan the surface of a block of material at varying focal depths to produce a 3D array of pits. Varying the focal depth of laser 502 can create etches beginning at the bottom and ending at the top of a block of material. Scanning the silicon block at each focal depth can pattern the entire block of silicon to produce a succession of layers.
[0041] As shown in FIG. 6 , after process 600 begins at 602 , controller 504 can begin by selecting the lowest z level at 604 and the first x, y point at 606 based on parameters entered by a user. Controller 504 can then send signals to drivers 506 , 508 , and 510 , respectively, which can then, based on the signals, cause the x-servo 512 , y-servo 514 , and z-servo 516 to move (if necessary) to the appropriate x and y positions and focal depth. Controller 504 can then send a signal to trigger laser 502 at 608 .
[0042] Controller 504 can then determine if an x, y point is the last coordinate for a particular focal depth (z level). If at 610 , controller 504 determines that an x, y point is not the last coordinate for the present z level, controller 504 can select the next x, y point at 612 . Controller 504 can then, as previously described, send a signal to the drivers which can then move the servos as needed, and again trigger laser 502 at 608 . Controller 504 can continue to move laser 502 to each x, y point for the present z-level.
[0043] Otherwise, if controller 504 determines at 610 that an x, y point at 610 is the last coordinate for the present z level, controller 504 can determine if the present z level is the final focal depth to be etched at 614 . If controller 504 determines that the present z level is not the final depth to be etched at 614 , then controller 504 can select the next z level at 616 . Then, at 606 , an x, y point for the new z level can be selected. Controller 504 can continue to move laser 502 to each x, y point for the new z level. Furthermore, controller 504 can continue to move laser 502 to a new z level after completing all x, y points selected for the particular z level. Alternatively, if controller 504 determines at 614 that the lowest z level or any other z level is the last level to be etched, controller 504 can end the process at 618 .
[0044] It should be understood that some of the above steps of process 600 of FIG. 6 may be executed or performed in an order or sequence other than the order and sequence shown and described in the figure. Also, some of the above steps of process 600 may be executed or performed substantially simultaneously where appropriate or in parallel to reduce latency and processing times.
[0045] SSLE can be used in several applications. For example, SSLE can be used in the fabrication of solar cells. SSLE can be used in processes for fabricating heterojunction solar cells with a machine for amorphous silicon deposition of 6 inch square standard industrial size substrates.
[0046] In some embodiments, controller 504 can be any of a general purpose device such as a computer or a special purpose device such as a client, a server, etc. Any of these general or special purpose devices can include any suitable components such as a hardware processor (which can be a microprocessor, digital signal processor, a controller, etc.), memory, communication interfaces, display controllers, input devices, etc. In some embodiments, memory can include a storage device (such as a non-transitory computer-readable medium) for storing a computer program (which can implement process 600 in some embodiments) for controlling the hardware processor. For example, controller 504 can be implemented as a personal computer, a laptop computer, any other suitable computing device, or any suitable combination thereof.
[0047] The hardware processor can use the computer program to present on the display content and/or an interface that allows a user to interact with the mechanisms described herein for using SSLE to create one or more wafers from a material, and to send and receive data through a communications link. It should also be noted that data received through the communications link or any other communications links can be received from any suitable source. In some embodiments, the hardware processor can send and receive data through the communications link or any other communication links using, for example, a transmitter, receiver, transmitter/receiver, transceiver, or any other suitable communication device. The input device can be a computer keyboard, a computer mouse, a touchpad, a voice recognition circuit, a touchscreen, and/or any other suitable input device.
[0048] In some embodiments, any suitable computer readable media can be used for storing instructions for performing the processes described herein. For example, in some embodiments, computer readable media can be transitory or non-transitory. For example, non-transitory computer readable media can include media such as magnetic media (such as hard disks, floppy disks, etc.), optical media (such as compact discs, digital video discs, Blu-ray discs, etc.), semiconductor media (such as flash memory, electrically programmable read only memory (EPROM), electrically erasable programmable read only memory (EEPROM), etc.), any suitable media that is not fleeting or devoid of any semblance of permanence during transmission, and/or any suitable tangible media. As another example, transitory computer readable media can include signals on networks, in wires, conductors, optical fibers, circuits, any suitable media that is fleeting and devoid of any semblance of permanence during transmission, and/or any suitable intangible media.
[0049] Although the invention has been described an illustrated in the foregoing illustrative embodiments, it is understood that the present disclosure has been made only by way of example, and that numerous changes in the details of implementation of the invention can be made without departing from the spirit and scope of the invention, which is only limited by the claim which follows. Features of the disclosed embodiments can be combined and rearranged in various ways. | In accordance with some embodiments, a method for using SSLE to create one or more wafers from a material is provided, the method comprising: using a laser light beam to etch pits in the material to create one or more layers of etch pits in a subsurface of the material; and dividing the material into one or more individual wafers with an etch. In accordance with some embodiments, a system for using SSLE to create one or more wafers from a material is provided, the system comprising: a controller for controlling the position of a focal point of a laser light beam with respect to the material and causing an irradiation of the laser light beam at a plurality of focal points; and an etch for splitting the material into the one or more wafers based on the plurality of focal points. | 1 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a division of application Ser. No. 280,044 filed July 6, 1981 and now U.S. Pat. No. 4,425,378 issued Jan. 10, 1984.
BACKGROUND OF THE INVENTION
This invention relates to an electroless nickel plating activator particularly for use on ceramic capacitor bodies as terminations, and more particularly to such an activator based upon palladium.
Ceramic or glass products to be electroless plated generally require a surface activation treatment prior to introduction into the plating bath. A typical activation consists of immersion into solutions of tin and palladium chlorides.
A serious limitation of this technique is that the plated films often have insufficient adhesion to the base material, necessitating additional steps such as etching, sandblasting, or the like, to roughen the surface and allow mechanical interlocking. Additionally, it is often desired to plate only part of an article, requiring masking from the roughening process, activator, or plating solution or all three. In the case of disc ceramic capacitors, a common practice is to plate the entire body, and then employ grinding to remove plating from the areas where it is unwanted.
It is an object of this invention to provide an activator for an electroless nickel plating on ceramic and glass bodies that bond well and make intimate electrical contact thereto.
It is a further object of this invention to provide an effective low cost method for selectively activating a ceramic capacitor body for a subsequent electroless nickel termination plating.
It is yet a further object of this invention to provide a low cost ceramic capacitor having electroless plated terminations making intimate electrical contact and strong physical contact with the ceramic body.
SUMMARY OF THE INVENTION
An electroless plating activator composition for sensitizing a ceramic body consists essentially of a homogenous combination of palladium, at least half as much silicon and a greater quantity of zinc than of silicon, all by weight. Best results are obtained when the silicon is less than about 36 times that of the palladium.
This composition may be deposited onto the surface of a ceramic body by any means, such as by vacuum deposition, sputtering, spraying, screen printing and brushing, that will provide a uniform layer wherein the Pd, Si and Zn are homogeneously dispersed.
A particularly useful form of the composition for spraying, screen printing or brushing is made by mixing organo-resinates of the expensive palladium with the silicon and zinc, the latter each preferably being in the form of powdered metal or powdered oxide or other oxidizable/oxidized form. The silicon and/or zinc may also each be introduced as an organo-resinate, having the advantages of ease of measuring and handling, convenience in storage and accounting, and providing easy dispersal of the metal in the activator composition. Whether in metal powder form or resinate form, it is preferred to include in the start activator composition an organic binder such as ethyl cellulose and an organic vehicle such as terpineol for adjusting the viscosity especially for screen printing. When a resinate component is used, the deposited layer of the activator composition is heated to from 500° to 750° C. to drive off the organic material leaving the palladium dispersed with the silicon and zinc, the latter being mostly oxides of silicon and zinc.
A small amount of the silicon will be withdrawn from the activator layer and introduced into the intergranular interstices of the ceramic body at the surface. This is thought to be a means by which the silicon is effective in improving the bond to the ceramic. The remaining silicon serves to bond the palladium particles to each other.
Electroless nickel plating on a ceramic substrate may be used in printed circuits on alumina substrates or as part of a barium titanate ceramic capacitor with nickel terminations. For such products, the activator of the present invention makes possible a simple, reliable and easily controlled method for making such products wherein the nickel layer is strongly bonded to the ceramic and is uniformly thick at about 40 micro inches or more as desired.
In a simple disc type capacitor the electroless plated nickel layers, and corresponding activator films, may serve as the capacitor electrodes as well as solderable terminations. In a monolithic ceramic capacitor having two groups of interdigitated buried electrodes, each of the electroless plated nickel layers may contact one group of the buried layers and serve as a solderable termination therefor.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows in perspective view a ceramic disc capacitor that may be of this invention.
FIG. 2 shows in side sectional view the capacitor of FIG. 1.
FIG. 3 shows in magnified detail a portion 27 of the capacitor of FIG. 2.
FIG. 4 shows in cross-sectional view a monolithic ceramic capacitor of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Example 1
Four discoidal barium titanate bodies having a thickness of 0.02 inch (0.5 mm) were immersed in a solution of SnCl 2 , then rinsed in water and transferred to a dilute solution of PdCl 2 . They were rinsed again and placed in a conventional electroless nickel bath, namely product #792 supplied by Allied Kelite Products Division of the Richardson Company, Des Plaines, Ill. This plating bath was preheated to 90° C. The ceramic bodies were removed after 3 minutes at which time about 50 micro inches (1.3 microns) of nickel film had been formed over the entire surfaces of the ceramic bodies. The nickel film can be abraded or etched from the perimeters of the ceramic bodies to leave two separate electrodes, e.g. for forming a disc or wafer type capacitor.
Copper wires of 0.02 inch (0.5 mm) diameter were soldered orthogonally to one and the other major surfaces of the plated bodies. Electrical properties were good, but in a lead strength test whereby the two leads were pulled apart, the nickel film bond to the ceramic bodies failed at less than 1 pound.
Example 2
Another group of four discoidal barium titanate bodies were first etched by immersion in fluoboric acid. After rinsing, these etched bodies had their surfaces activated in the tin and palladium solutions; they were electroless nickel plated; and they had leads attached all just as described for the capacitors of Example 1. The electrical properties were degraded, namely the dissipation factor increased an order of magnitude indicating damage to the ceramic caused by the etching. When subjected to the lead strength test, the average failure point was at 5 pounds (11 Kg). Failure was largely within the ceramic surface.
Example 3
An activator printing paste was prepared by first mixing 100 parts #318 terpineol and 4 parts of N-300 ethyl cellulose, both having been supplied by Hercules, Inc., Wilmington, Del. Then there was introduced in this paste 0.4 parts of 20% palladium resinate #7611 supplied by Engelhard Minerals and Chemicals, East Newark, N.J.
Referring to FIGS. 1, 2 and 3, a 35 micron thick coat (10) of this paste was screen printed onto one major surface of four 0.02 inch (0.5 mm) thick barium titanate discs such as disc 12. This screening step was repeated to deposit another paste coat (14) on the opposite major surface of discs (12). The coated discs (12) were then fired by raising the temperature in 10 minutes to a peak temperature of 615° C. and cooling thereafter at about the same rate. A faster heating cycle tends to cause a thermal shock induced cracking of the ceramic disc 12. After heating, the activator film is almost completely transparent. In related experiments it was determined that higher firing temperatures resulted in poorer plating. 750° C. is considered a practical maximum.
The ceramic discs were then immersed for about 3 minutes in the conventional electroless nickel plating solution of Examples 1 and 2. The bath was maintained at the elevated temperature of 90° C. The plating was excellent, i.e. the resulting nickel films 16 and 18 had an even thickness of about 50 micro inches (1.3 microns) and good contact with the capacitor dielectric disc was obtained as indicated by electrical measurements. The body was then rinsed in water and dried by heating at 120° C. for 15 minutes.
Copper wires 22 and 24 having a diameter of 0.02 inch (0.5 mm) were soldered at right angles to each other on the opposing nickel films 16 and 18, respectively. The resulting solder layers 26 and 28 are 60Sn40Pb. All material amounts in this example are given by weight.
In this way four capacitors 30 were made. By gripping the ends of leads 22 and 24 of each capacitor 30 and pulling with an increasing force, the force necessary to pull off either one or both of leads 22 and 24 was determined. In Example 3 this force was on average less than 1 pound, whereas it is desired to achieve a pull strength of at least 11/4 pounds, to avoid damage in subsequent capacitor lead bending or lead straightening operations as well as in capacitor encapsulation or capacitor assembly into printed wireboards or the like. These results are not substantially different than for those of Example 1. The only significant structural difference is that in the Example 3 capacitors the nickel plating was confined to the surface portions of the bodies that had been subjected to the screening of the activating paste and subsequent heating steps.
These results are summarized in the Table along with those of other examples. Examples 1 and 2 are omitted from the Table. No examples are included in the Table wherein the ceramic bodies have first been etched, but rather only changes in the electroless plating activator composition are presented for comparison here. The asterisks (*) indicate use of activators of this invention.
TABLE______________________________________Pd Si Zn PlatingEx. (wt (wt ratio (wt ratio Plating Adhesion# %) %) Si/Pd %) Zn/Si Quality (lbs)______________________________________3 0.08 0 0 Excellent 0.64 0.025 0 0 Excellent n.d.5 0.55 0 0 Excellent n.d.6 1.67 0 0 Edges Ran n.d.7 0.08 0.03 0.4 0 Fair-Poor 0.68 0.16 0.06 0.4 0 Poor 5.59 0.16 0.09 0.6 0 OK with 4.6 PdCl.sub.210 0.16 0.12 0.8 0 No Plate11 0.04 0.06 1.5 0.04 0.7 Poor-Fair 4.712 0.04 0.06 1.5 0.06 1.0 Fair 4.9*13 0.04 0.06 1.5 0.08 1.3 Excellent 4.2*14 0.04 0.06 1.5 0.12 2.1 Excellent 5.9*15 0.04 0.18 4.5 0.08 0.4 Poor-Fair n.d.16 0.04 0.18 4.5 0.17 1.0 Good n.d.17 0.04 0.18 4.5 0.27 1.5 Excellent 3.1*18 0.04 0.18 4.5 0.35 1.9 Excellent 3.8*19 0.04 0.18 4.5 0.52 2.9 Excellent 1.4*20 0.08 0.18 2.3 0.27 1.5 Excellent 3.2*21 0.02 0.18 9.0 0.27 1.5 Excellent 3.2*22 0.01 0.18 18. 0.27 1.5 Excellent 4.1*23 0.005 0.18 36. 0.27 1.5 Poor-Fair 1.624 0 0.18 0.27 1.5 No Plate25 0 0 0.81 Excellent 1.126 0.08 0 0.18 Excellent 1.727 0.34 0.73 2.1 1.08 1.5 Excellent 2.4*28 0.02 0.05 2.1 0.07 1.5 Good 2.1*______________________________________
For the examples listed in the Table, a 150 mesh screen with a 0.0005 inch (13 microns) emulsion was used for screen printing the experimental compositions. This produced a 35 micron thick wet film. If a deposition technique that produces a different thickness wet activator film is employed, the concentrations of Pd, Si and Zn must be adjusted so as to give the same weight per square area to achieve the same results as any one of these examples.
Examples 4-6
Ceramic disc capacitors were made in Examples 4, 5 and 6 by the same process as for those of Example 3 except that different amounts of the 20% palladium resinate were used as noted in the Table. The largest amount of palladium used, 350 micrograms per square centimeter in Example 6, provided good plating quality except that there was a tendency for the plating to spread into areas not coated with the sensitizer paste. It appears that diffusion follows the ceramic grain boundaries and a reduction in the activator firing temperature would likely minimize this unwanted spreading. However, cost considerations produce an overriding reason for keeping the palladium content lower.
Examples 7-10
The process of Example 3 was employed for making the capacitors of Examples 7 through 10, except that in addition to palladium there were added various amounts of silicon in the form of a silicon resinate. In Examples 9 and 10, plating could not be achieved at all until in the case of Example 9, the bodies were first dipped into the PdCl 2 solution after screening and firstng the "activator" paste. It is believed that at heating, the silicon combines with oxygen in the ceramic forming silica (SiO 2 ) that diffused into the ceramic and possibly this silica diffusion is at a fixed rate regardless of the amount of silicon in the screened activator film (10). In this event, the ratio of silicon to palladium in the activator film (10) of the completed capacitors of Example 8 would be greater than for capacitors of Example 7 which may explain why the lead bonding in the latter is superior. In any event, from these examples it is clear that a silicon additive to the palladium activator is a spoiler of the plating quality. It is believed that the silicon remaining at the ceramic surface oxidizes and improves the bond between the palladium and the ceramic but when the ratio of silicon to palladium is too high, the silica masks the palladium to such an extent that it is not available to the nickel plating solution and is thus made less effective as an activator agent. Since organic components must be removed and bonding takes place via solid state diffusion, it is to be excepted that firing temperatures below 500° C. would be inoperative. Capacitors fired at 400° C. in fact showed carbon residues and very low adhesion.
Examples 11-14
Yet a third ingredient, zinc, is added to the palladium and silicon containing activator pastes in Examples 11 through 14. The zinc is added as a zinc resinate. For all of these capacitors the adhesion of the nickel to the ceramic is greatly improved and for those of Examples 12-14 wherein the amount of zinc is at least equal to the amount of silicon (by weight), the plating quality ranges from fair to excellent. From this data of Examples 7-14, it is judged that the silicon to palladium ratio may be as low as about 0.4:1 if zinc were added to achieve strong good quality nickel terminations. Example 12 on the other hand shows that the zinc to silicon ratio may be as low as 1:1 to achieve satisfactory results.
Examples 15-19
Compared with capacitors of Examples 11 through 14, those of Examples 15 through 19 have a greater amount of silicon and again varying amounts of zinc while the amount of palladium remains the same. The zinc to silicon ratio again must be at least unity for good quality plating.
The composition of Example 17 was applied to an alumina body and electroless nickel plating applied by the same process. The results were essentially the same as for the barium titanate body.
A barium titanate dielectric body containing about 10% glass in an integranular phase was used as the body in a similar experiment. Only a medium plating quality resulted. A substantial amount of zinc was found to have left the activator layer and combined with the glass-ceramic body. A composition of 0.08 Pd, 0.18 Si and 0.43 zinc was then applied to the glass-ceramic and yielded excellent overall results.
Also the activator and method of this invention are applicable to a monolithic ceramic capacitor as illustrated in FIG. 4, wherein a ceramic body 40 has two groups 42 and 44 of sheet electrodes interdigitated with each other and buried in the body 40. The left and right (as shown) surfaces of body 40 are coated with the activator films 46 and 48 that contact extended portions of electrodes 42 and 44, respectively. The electroless nickel plating layers 50 and 52 conform and adhere to activator films 46 and 48, respectively. Solder layers 54 and 56 likewise conform and adhere to nickel layers 50 and 52, respectively.
Examples 20-23
In the activator paste used for making these capacitors, the ratio of zinc to silicon was fixed at 1.5 and various amounts of palladium were used. It is concluded that the activator layer (10) must contain more than 0.005 weight percent palladium to achieve good plating quality in a 35 micron thick (wet) screened layer. This corresponds to 0.18 micrograms palladium per square centimeter.
Examples 24 and 25
For both these examples there was no palladium. Ceramic bodies "activated" with the paste in Example 24 for which the zinc to silicon ratio is 1.5 could not be plated at all. However, in striking contrast the capacitors of Example 25 prepared with activator paste containing only zinc showed excellent plating quality but unsatisfactory lead strength. It appears that the zinc behaves itself somewhat like the activator agent, palladium. This is not fully understood. However, zinc is not by itself adequate for achieving both good plating and electrode adhesion.
Example 26
Here there is no silicon and again as in Example 25, the plating quality is excellent but the adhesion is marginally satisfactory.
Examples 27 and 28
The capacitors of Examples 27 and 28 as well as those of Example 20 have a silicon to palladium ratio of about 2 and a zinc to silicon ratio of about 1.5, while the absolute amounts of palladium that is incorporated in the activator layer (10) is, respectfully, 12, 0.8 and 3 micrograms per square centimeter. All produce satisfactory results even though the density of these elements in the activator paste cover a wide range. Excellent overall results are obtained for the lower amounts of silicon and zinc as in Example 22 wherein the palladium is as low as 0.35 micrograms per square centimeter, which is considered the low practical limit. Compared with the total cost of the capacitor, the cost of this tiny amount of palladium is insignificant.
In retrospect and with special attention to the results of Examples 8 and 11 through 14, it is clear that of the palladium provided appropriate amounts of zinc are used since the zinc additive has been shown itself to activate the plating to a limited degree as well as to counteract the spoiling properties which the silicon tends to have on plating quality. From Examples 11, 12 and 13 it is concluded that at least an equal amount of zinc as silicon is needed. | An activator composition paste includes a homogeneous dispersion of a palladium and commensurate amounts of silicon and of zinc. A screen printed layer of this paste is applied to a ceramic capacitor body to form electrodes, terminations or both. The body is heated to 615° C. and subsequently electroless nickel plated providing excellent electrical and mechanical connection of the plated nickel to the ceramic. | 2 |
FIELD OF THE INVENTION
This invention relates to a solvent composition.
BACKGROUND OF THE INVENTION
Chlorofluoroethanes such as 1,1,2,2-tetrachloro-1,2-difluoroethane (R-112), 1,1,2-trichloro-1,2,2-trifluoroethane (R-113) and the like have heretofore been used as solvent or detergent. These solvents have various excellent properties: they are nonflammable and low in toxicity to organisms; they can selectively solve fat, grease, wax and the like but do not attack plastics, rubber and like high molecular materials. However, R-113 and some chlorofluorocarbons are recently pointed out to be responsible for the destruction of the ozone layer in the stratosphere. The destruction of ozone layer will exert an adverse influene on the whole ecosystem including mankind. Thus, the use and production of chlorofluorohydrocarbons which may contribute to the destruction of the ozone layer are now restricted under international agreements and it is expected the use and production thereof would be totally banned.
Various compounds and materials have been proposed as solvents which may replace chlorofluorohydrocarbons. However, they have some defects and cannot fully satisfy the requirements as practical solvent. For example, chlorine containing solvents such as 1,1,1-trichloroethane, trichloroethylene, methylene chloride and the like are likely to cause environmental pollution. Alcohols and hydrocarbons are low in detergency and highly inflammable.
SUMMARY OF THE INVENTION
It is the primary object of the present invention to provide new compositions which can replace the conventional chlorofluoroethanes and which have excellent properties as solvent.
Other objects and feature of the invention will become apparent from the following description.
The present invention provides a solvent composition comprising chloropentafluoropropane and 1,1-dichloro-1-fluoroethane (hereinafter referred to as Composition I).
The present invention also provides a solvent composition comprising chloropentafluoropropane and dichlorotrifluoroethane (hereinafter referred to as Composition II).
We conducted extensive research to find a novel solvent composition having a high cleaning power and other properties required of solvent and found that a mixture of chloropentafluoropropane (R-235) and 1,1-dichloro-1-fluoroethane (R-141b) or dichlorotrifluoroethane (R-123) is a good solvent which can substitute the chlorofluorohydrocarbons.
The invention has been accomplished based on these findings.
DETAILED DESCRIPTION OF THE INVENTION
Composition I and Composition II of the invention will be described below in greater detail.
I. Composition I
Chloropentafluoropropane to be used in Composition I can be any of the isomers given below or a mixture of two or more of them.
(1) 1-Chloro-2,2,3,3,3-pentafluoropropane (R-235cb); boiling point=27° C.
(2) 3-Chloro-1,2,2,3,3-pentafluoropropane (R-235cc); boiling point=36° C.
(3) 1-Chloro-1,2,2,3-3-pentafluoropropane (R-235ca); boiling point=44° C.
(4) 1-Chloro-1,1,3,3,3-pentafluoropropane (R-235fa); boiling point=28° C.
The best result is obtained when R-235cb is used as the chloropentafluoropropane component.
Composition I usually comprises about 90 to about 30% by weight of chloropentafluoropropane (simply referred to as R-235 unless otherwise required) and about 10 to about 70% by weight of R-141b. When the ratio of the two component is within the above range, Composition I can achieve the remarkable effects that it selectively removes dirt such as grease, fat or the like from a substrate made of metal, plastics, rubber, etc. without attacking the substrate itself. In addition, Composition I is totally or substantially nonflammable. If the amount of R-235 in the composition is less than 30% by weight, the composition will be inflammable while use of R-235 in an amount more than 90% by weight reduces detergency of the composition. Of Composition I composed of R-235 and R-141b, a preferred one comprises about 70 to about 40% by weight of the former and about 30 to about 60% by weight of the latter.
Composition I is relatively stable in use under mild conditions. Composition I can contain a stabilizer which will improve chemical stability under severe conditions. Examples of stabilizers are given below.
* Aliphatic nitro compounds such as nitromethane, nitroethane, nitropropane, etc.
* Acetylene alcohols such as 3-methyl-1-butyn-3-ol, 3-methyl-1-pentyn-3-ol, etc.
* Epoxides such as glycidol, methylglycidylether, phenylglycidylether, 1,2-butylene oxide, cyclohexene oxide, epichlorohydrin, etc.
* Ethers such as dimethoxymethane, 1,2-dimethoxyethane, 1,4-dioxane, 1,3,5-trioxane, etc.
* Unsaturated hydrocarbons such as hexene, heptene, octene, 2,4,4-trimethyl-1-pentene, pentadiene octadiene, cyclohexene, cyclopentene, etc.
* Olefinic alcohols such as allyl alcohol, 1-buten-3-ol, 3-methyl-1-buten-3-ol, etc.
* Acrylates such as methyl acrylate, ethyl acrylate, butyl acrylate, etc.
* Phenols such as phenol, trimethylphenol, cyclohexylphenol, thymol, 2,6-di-t-butyl-4-methylphenol, butylhydroxyanisol, isoeugenol, etc.
* Amines such as hexylamine, pentylamine, dipropylamine, diisopropylamine, diisobutylamine, triethylamine, tributylamine, pyridine, N-methylmorpholine, cyclohexylamine, 2,2,6,6-tetramethylpiperazine, N,N'-diallyl-p-phenylenediamine, etc.
* Triazoles such as benzotriazole, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, chlorobenzotriazole, etc.
These stabilizers are usable singly or at least two of them can be used in mixture. Although variable with the kind of stabilizer, the amount of stabilizer is usually about 0.1 to about 10% by weight, preferably about 0.5 to about 5% by weight, of the total amount of Composition I.
II. Composition II
Chloropentafluoropropanes to be used in Composition II are the same as in Composition I. R-235cb is most preferable also in Composition II.
Dichlorotrifluoroethane to be used in Composition II can be any of the isomers shown below or a mixture of them.
(1) 1,1-dichloro-2,2,2-trifluoroethane (R-123); boiling point=27.5° C.
(2) 1,2-dichloro-1,2,2-trifluoroethane (R-123a); boiling point=28.2° C.
R-123 is preferable to obtain better results.
Composition II usually comprises about 90 to about 20% by weight of R-235 and about 10 to about 80% by weight of dichlorotrifluoroethane (simply referred to as R-123 unless otherwise required). If the amount of R-235 is more than 90% by weight, the cleaning power of the composition is reduced. If the amount of R-123 is over 80% by weight in the composition, the composition will dissolve plastics in a significant amount. Composition II preferably comprises about 70 to about 30% by weight of R-235 and about 30 to about 70% by weight of R-123.
R-235cb and R-123 are similar in boiling point. Thus, Composition II comprising R-235cb and R-123 shows substantially the same ratio of two components after repeated evaporation and condensation steps whatever the initial ratio may be. It is a great merit of Composition II.
Stabilizers as indicated above may be incorporated into Composition II in a similar amount.
R-235, R141b and R-123 are relatively easily decomposable before they reach the ozone layer in the stratosphere and hardly cause the destruction of ozone layer.
The solvent compositions of the invention dissolve away and remove fat, grease, wax, paint, printing ink, etc. from the substrate made of metal, high molecular compound such as plastics, rubber, etc. while hardly attacking the substrate. The composition of the invention are therefore very useful as solvent for eliminating grease and dirt from parts for electronic and electric devices, metal parts, etc., detergent for removing releasing agent from mold, etc.
The compositions of the invention are safe to use because they are nonflammable or hardly inflammable.
EXAMPLES
Given below are examples and comparison examples to clarify the feature of the invention.
EXAMPLES 1 TO 3 AND COMPARISON EXAMPLES 1 TO 2
Solvent compositions comprising R-235cb and R-141b were prepared in the weight ratio given in Table 1 below.
A test piece of wire net (50 mm×50 mm; 50 mesh) stained with spindle oil was immersed in a solvent obtained as above and washed to evaluate the degreasing power of each solvent.
The degreasing was carried out in the following steps.
(1) Immersion in solvent for 1 minute in the first vessel.
(2) Immersion in solvent for 1 minute in the second vessel.
(3) Steam cleaning for 1 minute in the third vessel.
The oil removing rate was determined as an index of degreasing power in accordance with the following formula: ##EQU1## wherein A is the amount of spindle oil on the net before cleaning and B is the amount of spindle oil after cleaning.
The results are shown in Table 1.
TABLE 1______________________________________ R-235cb/R-141b Oil removing rate (%)______________________________________Ex.1 80/20 99.92 60/40 1003 40/60 100Comp. Ex.1 100/0 652 0/100 100______________________________________
The results in Table 1 indicate that Compositions I of the invention have a high degreasing power.
EXAMPLES 4 TO 6 AND COMPARISON EXAMPLES 3 TO 5
Using mixtures of R-235cb and R-141b in varying ratios, the influence of solvent of the invention on plastics (weight increase by swelling of the material) was inspected.
Immediately after a test piece of plastics (5 mm×50 mm×2 mm) was immersed and kept in a mixture at 50° C. for 1 hour, the test piece was weighed to find the weight increase. The results are given in Table 2 below.
The plastics used were as follows.
(a) ...polyvinyl chloride
(b) ...acrylonitrile-butadiene-styrene copolymer
(c) ...polycarbonate
(d) ...polypropylene
TABLE 2______________________________________ Ratio Weight increase (%)* R-235cb/R141b (a) (b) (c) (d)______________________________________Ex.4 80/20 A A A A5 60/40 A A A A6 40/60 A B B BComp. Ex.3 20/80 B C C B4 100/0 A A A A5 0/100 B C C B______________________________________ *A: Increase of less than 3% B: Increase of 3% to 5% C: Increase of more than 5%
The results in Table 2 show that Compositions I of the Invention are low in the ability to dissolve plastics.
EXAMPLES 7 TO 9 AND COMPARISON EXAMPLES 6 TO 7
The procedure of Example 1 was followed except that the mixtures of R-235cb and R-123 were used in place of the mixtures of R-235cb and R-141b.
The results are given in Table 3 below.
TABLE 3______________________________________ R-235cb/R-123 Oil removing rate (%)______________________________________Ex.7 70/30 99.98 50/50 1009 30/70 100Comp. Ex.6 100/0 657 0/100 100______________________________________
The results in Table 3 show that Compositions II of the invention have a good degreasing power.
EXAMPLES 10 TO 12 AND COMPARISON EXAMPLES 8 TO 10
Following the procedure of Example 4 except that the mixtures of R-235cb and R-123 were used in place of the mixtures R-235cb and R-141b, the influence of solvent of the invention on plastics were checked.
Table 4 shows the results.
TABLE 4______________________________________ Ratio Weight increase (%)* R-235cb/R123 (a) (b) (c) (d)______________________________________Ex.10 80/20 A A A A11 60/40 A A A A12 40/60 A B B BComp. Ex. 8 20/80 B -- -- B 9 100/0 A A A A10 0/100 B C C B______________________________________
It is evident that Compositions II of the invention are low in the ability to dissolve plastics. | The present invention provides:
(1) a solvent composition comprising chloropentafluoropropane and 1,1-dichloro-1-fluoroethane; and
(2) a solvent composition comprising chloropentafluoropropane and dichlorotrifluoroethane. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not applicable.
TECHNICAL FIELD
[0002] The following relates generally to knowledge management systems, and more specifically to computer-implemented systems for gathering data from multiple organizations and analyzing and tracking the data gathered.
BACKGROUND OF THE INVENTION
[0003] Many complex activities in business and civic life involve exchanges of massive amounts of data between multiple organizations. Each organization often stores and produces information in a different format than other organizations involved in the activity. Organizations may store and organize information using a disparate array of software and techniques including search engines, document management systems, desktop file systems, database, and paper copies to store documents such as spreadsheets, text files or graphic files. This information often passes through multiple organizations in electronic format as an e-mail attachment or stored on removable media or in hard copies that may be faxed or mailed. The receiving organization may then convert the information to another form and store it in a separate files system. As a result, massive amounts of manual labor are often required to convert information from one format to another. Such manual translation not only results in increased costs, but often results in critical errors when data is copied incorrectly or crucial pieces of data are omitted from a copy altogether. Thus, a desire exists for a knowledge management tool capable of gathering information from disparate sources for storage in a common format, eliminating the need for manual translation of information from one organization's format to another.
[0004] Additionally, the use of manual translation in the data gathering process often precludes the gathering organization from using the raw data in later phases of the project, or later auditing the data-gathering process. For example, information is often not readily available for analysis, collaboration, or distribution and requires a high-degree of inefficient manual intervention to maintain. Manual maintenance of data becomes especially cumbersome as the number of organizations and criteria involved increase and the subject matter becomes more complicated. The lack of transparency in the process and information, the complexity involved with managing disparate environments, and the lack of audit capabilities limit the amount of structure that can be applied to the measure and evaluation of complex multi-dimensional data sets. Thus, a desire also exists for a knowledge management tool capable of transparently storing and organizing gathered information for later analysis and auditing purposes.
[0005] The common procedure utilized by organizations with regard to requesting and evaluating bids through the use of a request for proposals (RFP) exemplifies common knowledge management practices currently in use. In an RFP, an organization lays out its requirements for a new project and request proposals responsive to those requirements from prospective vendors. The organization often wishes to evaluate those vendors both on objective criteria such as total cost and on subjective criteria such as the vendor's reputation for quality service. To obtain such information, the organization produces an RFP in the form of a questionnaire containing a large number of questions—some which call for quantitative responses, some which call for qualitative responses. The organization may distribute the questionnaire in various formats ranging from a website posting accessed by prospective vendors through an Internet browser, to a paper document faxed or mailed to prospective vendors to a file stored to an electronic file e-mailed or delivered on disk to the prospective vendors. The prospective vendors will then produce a response to the RFP in various formats ranging from a printed document faxed or mailed to the requesting organization to an electronic file stored in various proprietary formats e-mailed or stored on disc and mailed to the organization.
[0006] Upon receiving responses to the RFP, the organization must somehow evaluate the responses. As a preliminary step, the organization must enter the quantitative responses from all the vendors' responses into a common format for grading. This often involves an administrative staff member of the organization manually entering data into a spreadsheet. As discussed above, such manual entering of data often leads to mistakes such as incorrect entry of data or omission of data altogether. Such a mistake could lead the organization to ultimately select a non-ideal vendor. Additionally, any information accompanying those numbers, such as a paragraph qualifying the vendor's ability to provide a component, is lost when only the number is entered into the spreadsheet. For the subjective responses, an administrative staffer may make copies of the responses and distribute the copies around the organization for evaluation. The distribution of multiple copies creates a security risk that a copy may be lost and be viewed by unauthorized personnel. The administrator must then enter those evaluations into a common format to store the grades. The evaluators may fill out a form with grades that an administrative staffer must transcribe into a spreadsheet for grading. Such tasks often quickly becomes overwhelming. For example, analysis involving 3,000 criteria may have 15,000 questions sent to 10 organizations with a request for response. The total number of response to be evaluated is 15,000×10=150,000. Additionally, as discussed above, any information contained in the responses not transferred by the evaluators into the scoring application may be lost.
BRIEF SUMMARY OF THE INVENTION
[0007] The present invention is directed to a computer-based system and method for requesting, gathering, evaluating, and scoring knowledge in which an application server presents a plurality of user interfaces to a first, second, and third groups of users. In some embodiments the application server may present some or all of the user interfaces through software for displaying the user interfaces on a plurality of remote computers connected by a network connection to the application server. In one embodiment, the first user interface allows a first group of users to create a number of response segments. The first user interface in some embodiments also allows a first group of users to designate which response segments will later require evaluation, as well as to define a set of data values to be presented as choices and displayed with some response segments where each data value is assigned a score. In one embodiment, a second user interfaces allows a second group of users to view some response segments along with a set of data values and select a choice among those values and to view other response segments without any set of data values and simply enter a response to the response segment. A third user interface in one embodiment allows a third group of users to view responses entered by the second group of users and evaluate those responses by selecting a choice from a set of data values. In some embodiments, the application server automatically scores the responses and selections entered by the second group of users using the scores associated with the data values selected by the second group of users in response to displayed response segments and the scores associated with the data values selected by the third group of users in evaluating the displayed responses.
[0008] In some embodiments, the second user interface may only display certain response segments to a specific user in the second group of users. The user interface may only display those response segments associated with that particular user's profile. Similarly, the third user interface in some embodiments may only display responses associated with a particular user's within the third group of users profile. In some embodiments, the first and third groups of users discussed above may belong to the same organization while the second group of users may belong to several geographically diverse organizations.
[0009] In some embodiments, the system stores and displays data stored in a relational database containing several related tables where each table contains a number of entries. The system may contain a table of response segments, a table of responses where each response is associated with at least one response segment, a table of evaluation segments where each evaluation segment is associated with at least one response segment, and a table of evaluations where each evaluation is associated with at least one evaluation segment. The relational database in some embodiments also contains a table of user responsibilities where each user responsibility is associated with at least one response segment or at least one evaluation segment, and a table of users where each user is associated with at least one user responsibility. The application server in some embodiments may limit a user's access to only those response segments and evaluation segments with which that user's user responsibility is associated.
[0010] The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. The novel features which are believed to be characteristic of the invention, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] For a more complete understanding of the present invention, reference is now made to the following descriptions taken in conjunction with the accompanying drawing, in which:
[0012] FIG. 1 is an illustration of several tables and associations between those tables of the relational database structure of one embodiment.
[0013] FIG. 2 is an illustration of a multi-tier server architecture for implementing one embodiment.
[0014] FIG. 3 is an illustration of a user interface in one embodiment that allows an administrator to select various elements of the Solutions Template to include in his or her program.
[0015] FIG. 4A is an illustration of a user interface in one embodiment that allows an administrator to define a program, projects within a program, and phases within a project.
[0016] FIG. 4B is an illustration of a user interface in one embodiment that allows an administrator to define the responsibilities of users within a specific project.
[0017] FIG. 4C is an illustration of a user interface in one embodiment that allows an administration to create and define user responsibilities.
[0018] FIG. 4D is an illustration of a user interface in one embodiment that allows an administrator to add or remove reference categories from the reference categories to which users with a specific responsibility have access.
[0019] FIG. 5A illustrates a user interface in one embodiment that allows an administrator to create criteria, enter information about a criterion, associate the criterion with a reference category, and assign response blocks to the criterion.
[0020] FIG. 5B illustrates a user interface containing various data control elements that allows an administrator to define text and associated numeric values for ratings in one embodiment.
[0021] FIG. 5C illustrates a user interface in one embodiment that allows an administrator to create a response block and define multiple response segments related to the response block.
[0022] FIG. 5D illustrates a user interface in one embodiment that allows administrator to create a Value Set.
[0023] FIG. 6 illustrates a user interface in one embodiment that allows a user to read criterion prompt and enter responses to the response segments of the response block associated with the criterion.
DETAILED DESCRIPTION OF THE INVENTION
[0000] Database Structure
[0024] Turning to FIG. 1 , examples of relational database tables and associations in one embodiment of the invention are shown. As is well-known in the art, each table (represented by a box in FIG. 1 ) contains a number of columns and a number of rows, where each column represents a field of information and each row represents a separate entry. Exemplary fields for some tables in one embodiment are listed in Table 1. Some embodiments may contain more tables or tables with different columns than the exemplary embodiment of FIG. 1 and Table 1. In some embodiments, each table has a column that serves as the primary key for the table such that each row contains a unique or primary ID in that column. FIG. 1 also illustrates the relationships between various tables in one embodiment through lines connecting the tables. As is known in the art, these relationships may be established by placing a foreign ID column, i.e. a column containing primary ID's of another column, in a table. These relational columns are not listed in Table 1. For example, the Response Segment table 111 may contain a column for Response Block IDs. Thus, a row in the Response Segment table 111 with an entry “5” in the Response Block ID column would be associated with the row of the Response Block table 110 with the primary ID “5.” Specific uses of the exemplary relational database tables of FIG. 1 are discussed below throughout the discussion of the functionality of one embodiment of the system.
TABLE 1 Criteria ID Name Type Status Rating Rating ID Sequence Name Numeric Value Response Block ID Name Description Response Segment ID Name Description Prompt Dependent Response Segment: Dependent Value Set ID, Dependent Value ID, Dependent Value Response Segment Value Set ID Name Value Set Value ID Name Score Responses Responder's User ID Response Segment ID Response Segment Value Response Segment Score Evaluation Block ID Name Description Evaluation Segment ID Name Description Prompt Dependent Evaluation Segment: Dependent Value Set ID, Dependent Value ID, Dependent Value Evaluation Segment Value Set ID Name Value Set Value ID Name Score Evaluations Responder User ID Evaluator User ID Evaluation Segment ID Evaluation Segment Value Evaluation Segment Score Application Privileges Feature ID Feature Name Function ID Function Name Report ID Report Name Reference Category ID Name Description Program ID Name Description Type Status Project ID Name Description Type Project Phases ID Name Description Project Responsibilities ID Name Description Start Date End Date % Score Subscription Administration Organization ID Contact Information Subscription ID Collaboration ID Administrator ID Organization Role ID Responsibility ID Responsibility Name Distribution Broker Subscription ID Organization ID Collaboration ID Solution ID Users ID Contact Information Organization ID Collaboration ID
System Architecture
[0025] Turning to FIG. 2 , in one embodiment a multi-tiered architecture used to store the relational database tables of FIG. 1 and to allow users to enter and view data by delivering various user interfaces to users over the Internet 212 via computer with a web browser interface 211 . In one embodiment, the multi-tiered architecture consists of an end-user tier 210 , a web tier/security zone 220 , an application server tier 230 , and a database tier 240 . While such a multi-tier system provides security and load balancing advantages, such an architecture is used only in some embodiments of the invention. Similarly, while specific components may appear separately in the exemplary embodiment of FIG. 2 , these functional components may be performed by more limited, more expansive, or different hardware in other embodiments. In one embodiment, the end-user tier 210 contains a client computer with a web browser interface 211 that connects to the web tier/security zone through the Internet 212 . In some embodiments, the client computers 211 may connect to the web tier/security zone 220 via a company intranet instead of via the Internet 212 . In one embodiment, the web browser interface 211 is a Java™-enabled.
[0026] The web tier/security zone 220 in one embodiment contains a router 223 and firewall 224 that connect the system to the Internet. The web tier/security zone in one embodiment contains web servers 222 for delivering user interfaces to client computers and network area storage, file & print servers 221 that may store copies (caches) of commonly-used reports and other data so that when a user request such data, the system need not contact the application server tier 230 or the database tier 240 . The file servers may store attachments uploaded by users and the print servers may allow a user in one location to send a document to a printer in another location. In one embodiment, a switch connects the network area storage file & print servers, the web servers 222 through a load balancer 225 , and the application server tier 230 through a firewall or VPN 227 to the end-user tier through a firewall 224 and a router 223 . The connections 251 between hardware elements may be made in one embodiment using 100 Base T or other data cables well known in the art to enable high-speed data transfer. In one embodiment, the firewall 224 and firewall or VPN 227 protect the system from access by unauthorized users.
[0027] In one embodiment, the application server tier 230 contains application & report servers 231 for storing programs that communicate with the database servers. The software on the client's computer may interact with the programs on the application servers to request information and generation of reports. A switch 232 may connect the database tier 240 and application & report servers 231 to the web tier/security zone 220 . These connections 252 may be made using GigE fiber channels or other data cables known in the art to enable high-speed data transfer. In one embodiment, the database tier contains database servers 243 connected to the application server tier 230 that may be connected to a storage area network 241 by a switch 252 . In one embodiment, the storage area network is a stack of hard drives for storing data for the database servers 243 . In one embodiment, the database servers 243 may include a data integration server 244 for accessing external data sources and prestaging that data, an OLTP (On-Line Transaction Processing) server 245 containing the actual database, and a reporting server 246 for load balancing. A data integration sever thus provides Publish and Subscribe services, as are known in the art. The connections 252 within the database tier may be made using GigE fiber channels or other data cables known in the art to enable high-speed data transfer.
[0000] System Operation
[0028] In one embodiment, the system presents each user with a control panel that allows the user to access all user interfaces to which that user is allowed access. From this panel, the user may access the user interfaces discussed herein. To create a new program in one embodiment, an administrator may start with a Solutions Template. A Solution Template may contain a set of pre-defined program 160 and project 161 structures containing pre-defined responsibilities 163 , pre-defined criteria 100 , pre-defined response blocks 110 , pre-defined evaluation blocks 120 , pre-defined scoring methodologies 190 , and pre-defined reports. FIG. 3 illustrates a user interface in one embodiment that allows the administrator to select various elements of the Solutions Template to include in his or her program. Using this interface, an administrator may select a table such as Criteria 100 or Reference Categories 151 from the pull-down menu 301 and the interface will list all the pre-defined columns for the selected table. The user may then add those columns to the table in its program by selecting the checkbox 302 corresponding to a particular pre-defined column. In some embodiments, the Solutions Template may evolve to include more elements as various administrators create custom elements for specific projects and add those elements to the Solutions Template. In some embodiments, the administrator may not use a Solutions Template and may simply begin adding columns to the tables using the interfaces described below.
[0029] In one embodiment, an administrator uses the user interface illustrated in FIG. 4A to define a program 160 , projects 161 within a program, and phases 162 within a project. The interface may contain a section 401 with various data entry devices such as text boxes 404 and drop down menus 405 that allow the administrator to define the programs 160 . Each new program is a new row in the Program table 160 where each of the data entry devices supplies information for a column. The system further defines a unique Program ID for the program. Similarly, the interface may contain section 402 with various data entry devices 404 , 405 that allow the administrator to define projects 161 of the program. Each new project is a new row in the Project table 161 where each of the data entry devices supplies information for a column. The system further defines a unique Project ID for each new project and also enters the Program ID of the associated program in the Program ID column of the Project table 161 . In some embodiments, a user may create a project independent of a program and later define the association between a project and a program. An administrator creates phases 163 using a similar interface and process. In some embodiments, the interface for creating phases may presented to the user as part of the same interface of FIG. 4A . In some embodiments, the user may bring up the window for adding phases by right-clicking a mouse on a project and selecting the “phases” option from the menu that appears when the user right clicks on the project name.
[0030] In one embodiment, the administrator controls user access to application features and functions 150 and reference categories 151 by defining responsibilities 163 such that users 181 assigned a particular responsibility may only access those application features and functions 150 and reference categories 151 associated with that responsibility 163 . The use of responsibilities allows the system to provide a collaborative environment across multiple organizations while providing security to limit user access only to authorized features and applications. FIG. 4B illustrates a user interface in one embodiment that allows an administrator to define the responsibilities of users within a specific project. In one embodiment, the interface illustrated in FIG. 4B may be presented to the user as part of the same interface of FIG. 4A . In some embodiments, the user may bring up the window for adding responsibilities by right-clicking a mouse on a project and selecting the “user responsibilities” option from the menu that appears when the user right clicks on the project name. Turning to the exemplary embodiment in FIG. 4B , the user is presented a list of responsibilities 163 on the right side of the screen in a nested list 410 in which the users already assigned to a responsibility are nested within that responsibility. On the left side of the screen, the user is presented a list of every user 412 with a checkbox 413 next to each user. To add users to a responsibility, the user selects a responsibility by clicking on a responsibility on the right side of the screen, selects the checkbox next to all users to be placed in a responsibility, and then selects the “Add” button 414 . When the user selects the “Add” button 414 , the system enters the Responsibility ID of the selected responsibility in the Responsibility ID column of the selected users' rows in the Users table 181 .
[0031] In some embodiments, a user defines a number of reference categories 151 , and may link each criteria to a reference category (one embodiment of a user interface for linking a criteria to reference category is discussed below). The Reference Category table 151 may have a recursive column that allows a reference category to link back to a parent reference category, thus creating a parent-child structure. Using this parent-child structure, an administrator may grant users of a certain responsibility access to criteria linked to several reference categories simply by granting users with that responsibility access to the parent reference category. In some embodiments, reference categories may be further grouped into Reference Category Types where a single reference category may be a member of several Reference Category Types. A user may also improve the relevance of search results by searching only specific reference categories.
[0032] In some embodiments, the system may also provide the user with a user interface that allows the user to create and define responsibilities. In some embodiments, user responsibilities may be presented to the users as “roles.” A user interface in one embodiment that allows an administrator to add and define responsibilities is illustrated in FIG. 4C . The user interface may contain data control elements such as text fields 420 and drop down menus 421 for defining columns of information of the responsibility. In some embodiments, the user may use a drop down box 421 to define parent responsibilities. By allowing administrators to define parent responsibilities, the system allows administrators to assign some users multiple areas of responsibility by assigning the user a parent responsibility with several children. In some embodiments, the user may right-click a mouse on the responsibility name to bring up a menu that provides access to more user interfaces for further defining user responsibilities. The menu may provide access to a user interface such as the interface illustrated in FIG. 4D . In the user interface illustrated in FIG. 4D , the administrator may add or remove reference categories 151 from the reference categories to which users with a specific responsibility have access using the “Add” 430 and “Remove” 431 buttons. The selected reference categories appear in the nested list 432 . In some embodiments, the administrator may also add and remove application privileges 150 to which users with a specific responsibility have access using the “Add” 430 and “Remove” 431 buttons. Application privileges 150 include application features and functions. Thus, in a responsibility-based configuration of the program, the application only grants the user access to features and functions associated with that user's responsibility. The application further only provides the user access to reference categories associated with that user's responsibility. In some embodiments, an administrator may assign a user more than one responsibility in which case the application may allow the user to select a single responsibility for a specific session.
[0033] FIG. 5A illustrates a user interface in one embodiment that allows an administrator to create criteria 100 , enter information about a criterion, associate the criterion with a reference category 151 , and assign response blocks 200 to the criterion. In some embodiments, when a user creates a new criterion, the system assigns the criterion a system generated Criterion ID. The user may also associate a Rating 101 with the criterion. In the embodiment illustrated in FIG. 5A , a drop-down menu 501 lists the text of available ratings and allows the user to select a rating. When a user selects a rating, the system places the Rating ID of that rating in the Rating ID column of that criteria's row in the Criteria 100 table. FIG. 5B illustrates a user interface containing various data control elements that allows the administrator to define text and associate numeric values with a set of ratings in one embodiment. In some embodiments, the rating 101 associated with a criterion 100 may factor into the scoring methodology 190 . In one embodiment, the value assigned to the rating will be applied to the score of responders or evaluators for criteria assigned that rating. Thus, an administrator may assign additional weight in a later scoring to responses to criteria with one rating over criteria with another rating.
[0034] In some embodiments, the user may associate a criterion with a reference category 151 . When the user places the criterion in a reference category, the system enters the Reference Category ID of the selected reference category in the Reference Category ID column of the criterion's row in the Criteria table 100 . In one embodiment, the user may place a criterion in a reference category by selecting the Reference Category Type from a pull-down menu 502 , selecting the appropriate reference category from the nested list 503 and selecting the “Add” button 504 . In some embodiments, this selection process is similar to the process of adding a user to a specific responsibility as illustrated in FIG. 5B . Such a common interface allows the user to quickly learn to use the system.
[0035] FIG. 5C illustrates a user interface in one embodiment for creating a response block and defining multiple response segments related to the response block. In some embodiments, the user may associate a response block 110 with a criterion 100 . A user may directly select a response block for a criterion in some embodiments. In some embodiments, the user may use button 530 as illustrated in FIG. 5C to assign the current response block to all criteria of the same type (note both response blocks and criteria have a “Type” column). In some embodiments, when the user creates a Response Block the system assigns a Response Block ID. The user may define the response block by entering data in a number of data control elements such as text boxes and drop-down menus. In some embodiments, the user may then define one or many Response Segments 111 associated with the Response Block. When the user creates a new response segment, the system enters the Response Block ID of the current response block in the Response Block ID column of the response segment's row in the Response Segment table. The system may also assign a Response Segment ID to the new response segment. In some embodiments, the user may also choose a Value Set 120 from a drop down menu 533 for each Response Segment 111 . When the user selects a value set for a response segment, the system assignss the Value Set ID of that value set in the Value Set ID column of the response segment's row in the Response Segment table 111 . In some embodiments, the user may use drop down menus 534 , 535 to define a data dependency for a response segment such that when a responding user enters of a specific value 121 in the response segment 111 , the system presents the responding user with an additional response segment or segments not presented to users not entering the specified value. The administrator may define these dependency rules by specifying the dependent response segment name and the value set value that triggers the system to present the user with that dependent response segment or segments. In some embodiments, the system stores the dependency rule as part of an on-entry data validation process that the system performs each time a responding user enters data. In some embodiments, the user may further specify whether a Response Segment 111 will require evaluation. A user may wish to require evaluation of a specific response segment where the response segments prompts the user for qualitative data not easily included in a scoring system without further quantitative evaluation. The process of creating evaluation blocks 130 is discussed in detail, below.
[0036] FIG. 5D illustrates a user interface in one embodiment for creating a value set 120 , 140 . In some embodiments, value sets may be used both in response segments and evaluation segments. The system may assign each newly created value set 120 , 140 a Value Set ID. In the embodiment shown in FIG. 5D , an administrator may use the same user interface to create Response Segment Value Sets 120 and Evaluation Segment Value Sets 140 . Value sets provide responding users with a set of responses from which to select when responding to a response segment associated with that value set. In one embodiment, the user may configure the value set 120 to contain data entry controls that allow the user to enter responses in multiple forms including binary, text, dates, data ranges, a list of values, or even attach documents. The user may define the value set using the data entry elements 540 . A value set 120 may contain data entry controls that allow the user to provide any type of response. In some embodiments, certain data controls will have values 121 associated with each value set. The user may create new values using the data entry controls 541 . When a user creates a new value, the system may assign each value 121 a Value ID. In some embodiments, the user may assign each value 121 a text label as well as a numerical score. This numerical score may figure into a scoring criteria. For example, a value set may contain four values, each of which are given a different numerical score reflecting the desirability of the value. Since the administrator assigns numerical scores to values before responding users even enter any data, the responding users' responses may be used in scoring calculation without any other manual action by an administrator.
[0037] While the system may automatically score user responses to Value Sets 120 with lists of values 121 containing associated scoring numbers, the system in some embodiments may also provide a separate user interface that allows a separate group of users—evaluators—to evaluate other types of responses. To accomplish this, in some embodiments the user may choose to create and associate an evaluation block with a response segment that contains qualitative information. In response to a user indicating that a particular response block will require evaluation, the system enters the Response Segment ID of that response segment in the Response Segment ID column of the new evaluation block's row in the Evaluation Block table 130 . The system may assign new evaluation blocks 130 a Evaluation Block ID. Each evaluation block 130 may contain any number of evaluation segments 131 . In some embodiments, the administrator defines an evaluation block using a user interface similar to the interface illustrated in FIG. 5C using the data control elements 531 . In some embodiments, when the user creates an evaluation segment using the data control elements 532 , the system assigns an Evaluation Segment ID to the new evaluation segment. The system may also assign the Evaluation Block ID of the current evaluation block in the Evaluation Block ID column of the evaluation segment's row in the Evaluation Segments table 131 . Just as with response segments 111 , the user may assign a value set 140 to each evaluation segment. In some embodiments, these value sets 140 may contain a number of values 141 with system-generated IDs, and user-entered text labels and numerical values. An administrator may create and edit value sets 140 using the user interface illustrated in FIG. 5D . In some embodiments, an administrator would likely not create a value set 140 without a set of values 141 since the purpose of evaluators is to assign a numerical value to a qualitative response inputted by a responding user.
[0038] As discussed above, several tables may include scoring elements, including value set values (for use with both response segments and evaluation segments), ratings, project responsibilities, and reference categories. In some embodiments, the user may use a Formula Builder to create formulas that combine various score elements For example, a user may define a formula to make all scored elements within a of a certain reference category type equal 25% of a total score. In another example, a user may choose to weigh the evaluation scores entered by users belonging to various responsibilities differently. A user could also use the ratings assigned to criteria in some category and weigh responses to criteria differently for criteria with different ratings. In some embodiments, the Formula Builder may use the Scoring Methodology table 190 to store relationships to scoring elements. Such formulas may be stored as scenarios that provide decision makers with multiple views and an audit trail of the scoring elements.
[0039] After a user has defined criteria, in some embodiments, the system allows respondents from disparate organizations to respond to the criteria through the web-based user interface. FIG. 6 illustrates a user interface in one embodiment that allows a user to read criterion prompt 601 and enter responses to the response segments 603 of the response block 602 associated with the criterion 100 . In one embodiment, the user interface also contains a nested list 604 of reference categories and the criteria within each category. The nested list may contain icons or other visual cues next to each criterion that indicates to the responding user whether the responding user has responded to all response segments in that criterion. The nested list may further allow the responding user to navigate within the criteria.
[0040] The system may allow the responding user to view and access response segments in reference categories associated with that responding user's responsibility. The responding user may be required to respond to any number of data control elements including text boxes, checkboxes, drop down menus, or prompts to attach a file. In some embodiments, when a user enters a response to a response segment, the system stores that response as a row in the Responses table 122 . The system may create a new Response ID for the response and enter the Response Segment ID and User ID into the appropriate columns of the response's row in the Response table. The system may also enter the Value ID into the appropriate columns of the response's row in the Response table if the user selected a value. Additionally, as discussed above, the system may perform an on-entry data validation process when the responding user enters data where that process may cause the system to present additional or different response segments to the responding users based on the responding user's previous response.
[0041] As discussed above, in some embodiments a separate group of users from the responding users may read qualitative responses entered by responding users and answer a series of quantitative questions to evaluate the response. In some embodiments, the system provides access to responses only in reference categories associated with the evaluating user's responsibility. The system may further limit the evaluating user's access to specific users. In some embodiments, the system pulls specific responses from the database and presents them in read-only format to the evaluating user. The evaluating user may evaluate responding users' responses using a user interface similar to the user interface illustrated in FIG. 6 . The evaluating user may view a response in the text box 601 and then evaluate the response by responding to evaluation segments 603 within the evaluation block 602 . In some embodiments, user interface may contain a nested list of reference categories 604 that the evaluating user may use for navigation or as a visual guide as to what responses remain to be evaluated.
[0042] Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps. | A computer implemented system and method for requesting, gathering, evaluating, and scoring knowledge. The system includes a first user interface for allowing a first group of users to define prompts and response choices, a second user interface for allowing a second group of users to view prompts and select response choices and view prompts without response choices and enter responses, and a third user interface for allowing a third group of users to evaluate previously-entered response by viewing the responses and selecting response choices. The system may automatically score the responses of the second group using scoring elements embedded in the response choices. The system may also include a relational database of related tables for storing the prompts, response choices, responses, evaluations, and user information. The system may also limit a user's access to various records based on the user's profile or a user responsibility associated with the user. | 6 |
BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention relates to a long-lasting collagen and its manufacturing method, and more particularly to a method of producing a collagen by adding γ-polyglutarmic acid (γ-PGA) to the collagen and going through two crosslinking processes to obtain the long-lasting collagen. The invention not only increases the storage time of the collagen in human body, but also achieves a better biocompatibility and provides a higher value for practical applications.
2. Description of Related Art
As we get older, our skin ages and loses its charm and healthy glow, causing wrinkles and tough inelastic skins, since the metabolic capability of dermis under the skin reduces with age, and the dermis is a main factor of the elasticity of skin. Reduction in the metabolic capability of skin will lead to skin aging, and thus various different rejuvenation methods are developed and available in the market. Among these rejuvenation methods, facial filler gives the best effect so far, and facial filler can be divided into two main types of materials: a synthetic material and a natural material. The synthetic material includes: silicone, hydroxyapatite (HAP), polylactic acid (PLA), polymethyl methacrylate (PMMA) and hydroxyethylmethacrylate (HEMA), etc. The natural material includes: botox (BT), autologous fat, collagen and hyaluronic acid (HA), etc.
However, the synthetic facial filler has the following drawbacks:
1. Silicone exists permanently in human body after being injected into the human body and it will cause long term inflammation and granulomas, and thus the silicone must be removed by operation. In addition, silicon may migrate due to gravitational force, and thus U.S. Food and Drug Administration (FDA) prohibits applying silicon into human beings by laws.
2. In a hydroxyapatite (HAP) material such as Radiesse, the only facial filler meeting the laws and regulations set forth by the U.S. Food and Drug Administration (FDA). Although HAP can be maintained for 2 to 5 years, nodule may occur sometime, particularly at the positions of mouth and lip, and it gives a bad look.
3. Poly l-lactic acid (PLLA) is generally used as an injection material. Although PLLA has been approved by U.S. Food and Drug Administration (FDA), granulomas may still occur, and PLLA has the highest frequency of occurrence of granulomas among all facial fillers.
4. Polymethyl methacrylate (PMMA) comes with an excellent biocompatibility, but it cannot be degraded in human body and becomes a bio-accumulative substance. Although PMMA is a permanent implantation material, granulomas also occurs easily, and thus many countries have banned the use of polymethyl methacrylate (PMMA) for hypodermic injection.
5. Hydroxyethylmethacrylate (HEMA) has a drawback similar to that of the polymethyl methacrylate (PMMA), but it contains a hydroxyl radical (—OH), and thus its elasticity is enhanced after being applied. However, PMMA will be hardened as time goes by.
In summation, the shortcomings of the synthetic facial filler material reside on its causing serious inflammations and having major side effects on human bodies.
Further, the natural facial fillers also have the following drawbacks:
1. Botox (BT) disables some of the biological functions of nerves and muscles by holding back the release of acetylcholine to achieve the effect of removing dynamic wrinkles, but botox (BT) also disables some of the biological functions of muscles, and the muscles will be degenerated after a period of time, and the facial expression of a patient will be unnatural when smiling. As the muscle activity is reduced, patients have to massage the injecting position everyday. In addition, researches reports show that there is 1% of fatal risk for an overdose of botox (BT).
2. Autologous fat is made of a material coming from a patient's autologous fat, and thus the biocompatibility is very high, but the time for the autologous fat to be remained in human varies greatly due to the fat source and the individual difference of the patient, and the time varies from months to years. On the other hand, the autologous fat has larger particles that cannot fill wrinkles or small lines in a small area, and thus the effect and range are very limited.
3. There are different collagens including human collagens, cadaveric collagens, bovine collagens and porcine collagens, etc, wherein the bovine collagen has been used for more than 20 years, and approved by the U.S. Food and Drug Administration (FDA). As mad cow disease existed in both animals and humans explodes and has the risk of infection. Although human collagen has passed the approval of the U.S. Food and Drug Administration (FDA), human collagen is not available easily, and its price is higher than other materials. The cadaveric collagen is also not available easily as the human collagen, and the particle size is larger than the human collagen falling within a range of micrometer (μm) and millimeter (mm) due to the factor of cultivation environment, and thus a thicker and larger needle is needed and it will cause additional pain to patients.
4. Since hyaluronic acid (HA) is a polysaccharide composed of two monomers (such as N-acetyglucosamine and D-glucuronic acid) that can go through a complete metabolism, but the structure of the monomer (such as N-acetyglucosamine) is very close to heparin, such that if there is a wound, the monomer (N-acetyglucosamine) will be used for filling, and the quantity of hyaluronic acid (HA) will be reduced. Since hyaluronic acid (HA) can enhance the combination of matter under the dermis and cannot make the skin elastic, therefore it is necessary to avoid the wound from being pressed by external forces and further hurting the wound after the implantation. On the other hand, the movement of muscles accelerates the absorption of hyaluronic acid (HA), and thus patients have to avoid excessive facial expressions.
In summation of the foregoing materials of the natural and synthetic facial fillers, the level of inflammation caused by collagens is the lowest, and thus collagens can be used extensively, but they still have the following drawbacks:
1. The time of collagens remained in human body is short, and uncrosslinked collagens will be degraded and absorbed in human body within three months, and collagens crosslinked by a crosslinking agent such as glutaraldehyde can remain a human body for six months, which is still too short, so that patients have to apply an injection for the supplement frequently, and it causes tremendous inconvenience.
2. Collagens are biological poisonous, and the collagens crosslinked by glutaraldehyde have a high concentration of remained glutaraldehyde, which is biologically poisonous and harzardous to human health.
Obviously, the conventional collagens still have many drawbacks and require further improvements.
SUMMARY OF THE INVENTION
In view of the foregoing shortcomings of the conventional collagen with short storage time and biological poison, the inventor of the present invention based on years of experience in the related industry to conduct extensive researches and experiments, and finally developed a long-lasting collagen and invented a manufacturing method of the collagen in accordance with the present invention to overcome the shortcomings of the prior art.
Therefore, it is a primary objective of the present invention to provide a long-lasting collagen, wherein a γ-polyglutarmic acid (γ-PGA) is added into a collagen and gone through a crosslinking process twice to obtain a long-lasting collagen with a uniformly and completely crosslink and a storage time increased by two to three times, so as to overcome the shortcomings of the conventional collagens having a short storage time and requiring an injection for suppment frequently.
Another objective of the present invention is to provide a low biologically poisonous collagen that uses glutaraldehyde of a very low concentration to uniformly and completely cross link the collagen with the glutaraldehyde to obtain remained glutaraldehyde of a very low concentration while providing a collagen with a better biocompatibility, so as to overcome the shortcomings of the conventional collagen having a high concentration of remained glutaraldehyde and a biologically poisonous glutaraldehyde that are harmful to our health.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention, as well as its many advantages, may be further understood by the following detailed description and drawings in which:
FIG. 1 is a flow chart of the present invention;
FIG. 2 is a schematic view of the chemical structure of γ-polyglutarmic acid (γ-PGA);
FIG. 3 is a curve of standard solutions of the collagen; and
FIG. 4 is a schematic view of test results of Group A, B and C samples with the same concentration in the degrading speed of a collagenase.
DETAILED DESCRIPTION OF THE INVENTION
To make it easier for our examiner to understand the technical measures and operating procedure of the invention, we use preferred embodiments together with the attached drawing for the detailed description of the invention.
The present invention discloses a long-lasting collagen and its manufacturing method, wherein a collagen is prepared, and a γ-polyglutarmic acid (γ-PGA) is added into the collagen, while going through a predetermined manufacturing process to obtain a long-lasting collagen. The chemical structure of γ-polyglutarmic acid (γ-PGA) is shown in FIG. 2 , and the amine linkage (—CONH) formed by linking an amino group (—NH 2 ) of the γ-polyglutarmic acid (γ-PGA) and a carbonyl group (—COOH) of a (residue group) which is called γ-linkage, and the linkage is relatively not easy to be degraded rapidly by the attack of an enzyme in human body, and the γ-polyglutarmic acid (γ-PGA) significantly resists the degrade of enemzes in human body to greatly retard the degrade of collagens in human body.
With reference to FIG. 1 , the long-lasting collagen is manufactured by the following procedure:
Step 1: Scrape extra tissues: Firstly, scrape extra muscle and fat tissues, and cut the remaining portion into small segment tissues.
Step 2: Remove grease: Dip the small segment tissues in acetone to remove grease, and rinse the small segment tissues twice until the grease is removed completely.
Step 3: Imbibition: Dip the degreased small segment tissues in salt water (with a concentration is 1%) at a predetermined temperature (4° C.) for a predetermined time (24 hours), and then dip it in citric acid solution of a specific pH value (4.5) for the predetermined time for the imbibition of the small segment tissues.
Step 4: Digestion: Dip the imbibited small segment tissues in a first solution (which is a mixed solution of pepsin and hydrochloric acid with a concentration of 0.5M) at the predetermined temperature for the predetermined time to digest the small segment tissues into a second solution.
Step 5: Centrifugal Separation: Separate the digested small segment tissues from the second solution by performing a centrifugal separation of the second solution in a first predetermined condition (wherein the weight of the second solution is equal to 5500 g).
Step 6: Salt-out: Add a salt water solution into the second solution to prepare a third solution (with a concentration of 0.8M), while shaking the solution severely until a cloudy substance if formed.
Step 7: Collect lower-layer precipitate: Perform the centrifugal separation to the third solution in a second predetermined condition (wherein the weight of the second solution is equal to 22000 g) while collecting a lower-layer precipitate, and then place the lower-layer precipitate in water twice, while adding sodium hydroxide (NaOH) with a concentration of 0.1N) to adjust the pH value to form a fourth solution (with a pH value of 7).
Step 8: Freeze Drying: Freeze the fourth solution at another predetermined temperature (−20° C.) for the predetermined time, and then dry the solution to obtain a collagen (which is a Type I collagen).
Step 9: Mix with the γ-polyglutarmic acid (γ-PGA): Prepare the collagen as a collagen solution (with a concentration of 35 mg/ml), while mixing a predetermined quantity (4 ml) of the collagen solution with the same predetermined quantity of γ-polyglutarmic acid (γ-PGA) to produce a fifth solution.
Step 10: Perform a first crosslinking: Titrate another predetermined quantity (0.5 ml) of glutaraldehyde solution (with a concentration of 0.05%) in the fifth solution by a pump (which is a tubing pump) while blending the solution at a predetermined rotating speed (250 rpm) for another predetermined time (30 minutes) to perform a first crosslinking to the collagen and glutaraldehyde in the fifth solution.
Step 11: Perform a second crosslinking: Finally, repeat Step 10 to complete the second crosslinking to obtain the long-lasting collagen.
The degrade-resisting effect of the long-lasting collagen of the invention can be proved according to a Bicinchoninic acid (BCA) testing procedure:
1. Uniformly mix a testing agent A and a testing agent B in a ratio of 50:1 by volume to prepare a BCA testing agent.
2. Add a sample A, a sample B and a sample C of 25 μl each into each groove of a 96-hole titration plate.
3. Add 200 μl of the BCA into each groove, and let it sit still at 37° C. for 30 minutes, such that each sample is reacted completely.
4. Finally, measure the absorption value of each group sample by an immune enzyme spectrophotometer, wherein the measuring wavelength is 650 nm.
In the preparation of the testing agent A, 40 mg of sodium tartrate (Na 2 C 4 H 4 O 6 .2H 2 O) is dissolved in 10 ml of 0.5M sodium hydroxide (NaOH) solution. After the sodium tartrate is dissolved completely, 1 g of sodium carbonate (Na 2 CO 3 ) is added and blended with the solution until the solution is in a clear transparent state.
In the preparation of the testing agent B, 0.2 g of sodium tartrate (Na 2 C 4 H 4 O 6 .2H 2 O) is dissolved in 2 ml of 0.5M sodium hydroxide (NaOH). After the sodium tartrate is dissolved completely, deionized (DI) water is added until the volume of the solution reaches 10 ml, and finally 0.3 g copper sulfate (CuSO 4 ) is added into the solution until the solution is in a clear blue state.
The Group A sample is 4 ml of collagen solution at a concentration of 35 mg/ml.
The Group b sample is 4 ml of collagen solution at a concentration of 35 mg/ml, and 0.5 ml of the glutaraldehyde solution is dropped within one minute by the pump, while blending and mixing the solution uniformly at a rotating speed of 250 rpm to perform a first crosslinking. After the first crosslinking, 0.5 ml of glutaraldehyde solution is dropped, and blended to mix with the solution at a rotating speed of 250 rpm for 30 minutes to perform a second crosslinking. In the preparation of the glutaraldehyde solution, 400 μL of glutaraldehyde is dissolved into 7.6 ml of the phosphate-buffered saline (PBS) solution to complete preparing the glutaraldehyde solution at a concentration of 0.5%.
The Group C sample is the long-lasting collagen obtained from the manufacturing method in accordance with the present invention, and the BCA testing method is adopted for the testing, and thus it is necessary to dissolve the γ-polyglutarmic acid (γ-PGA) into a phosphate-buffered saline (PBS) solution for completing the testing.
In addition, the BCA testing method is used for testing a standard collagen solution to obtain an absorption value x at a wavelength 650 nm of the standard collagen solution, while the absorption value x is substituted in an equation y=0.002x+0.074 to obtain a value of y, wherein the value of y in the equation indicates the concentration of peptide linkage in the standard collagen solution to obtain the graph of the standard collagen solution as shown in FIG. 3 . In the figure, the relation of an absorption value at a wavelength 650 nm of the standard collagen solution versus a concentration of a peptide linkage is shown.
In the standard collagen solution, 2 ml of collagen at a concentration of 35 mg/ml is dissolved in 5 ml of 0.025N acetic acid solution, and then the phosphate-buffered saline (PBS) solution is diluted to complete the preparation of the standard collagen solution.
With reference to FIG. 4 for Group A, B and C samples in collagenases of the same concentration, the testing results obtained by the BCA testing method show that: On the 11 th day of the experiment, the concentration of the solution of Group A sample in the peptide linkage is 2.052 mg/ml; the concentration the solution of Group B sample in the peptide linkage is 1.77 mg/ml; and the concentration of the solution of Group C sample in the peptide linkage is 0.87 mg/ml. From the aforementioned results obtained from the same experimental conditions, the degrading speed of the Group C sample is much slower than the degrading speeds of the Group A and B samples, indicating that the Group C sample has a better resistance to the degrading effect and a slower degrading speed of the enzymes in human body approximately equal to half of that of the Group B sample. From the present clinical testing result, the Group B sample can be stored and remained in human body for 6˜9 months, and thus we infer that the storage time of the Group C sample in human body is approximately equal to 12˜18 months.
On the other hand, the γ-polyglutarmic acid (γ-PGA) in the the Group C sample is linked by a γ-linkage, and the amine linkage in human body is an α-linkage, and thus the enzyme for degrading the γ-linkage of a DNA sequence in a human body is in an inactivated state. Researches point out that it takes 6˜7 months to activate this enzyme, and thus if a polypeptide of the γ-linkage enters into a human body, it will take at least 6˜7 months to start degrading the polypeptide, indicating that a γ-polyglutarmic acid (γ-PGA) and a collagen polymer material (such as the Group C sample) takes at least 18˜25 months to be degraded completely in human body.
A cell (a 3T3 fibroblast) is used for evaluating the biocompatibility of the Group A, B and C samples: the Group A, B and C samples are cultivated together with the cell for 3 days. With the following data, we can know about the information of cell activity, survival rate, quantity, senescence and genetic toxicity:
1. Mitochondrial activity assay (MTT): From the testing of the mitochondrial activity of the cells cultivated together with the Group A, B and C samples, we can know about the activity of the cells.
2. Lactate Dehydrogenase (LDH): From the testing of the Lactate Dehydrogenase (LDH) in the cells cultivated together with the Group A, B and C samples, we can measure the survival rate of the cells.
3. Total DNA Content: From the testing of the total DNA content in the cells cultivated together with the Group A, B and C samples, we can analyze the quantity of the cells.
4. b-galactosidase: From the testing of the b-galactosidase in the cells cultivated together with the Group A, B and C samples, we can measure the senescence of the cells.
5. Chromosome Aberration: A Giemsa stain is used to test the chromosome aberration cultivated together with the Group A, B and C samples, we can know about the genetic toxicity of the Group A, B and C samples to the cells.
The testing results are listed in the following table, wherein the control group in the table is the aforementioned standard collagen solution:
Control Group
Group A Sample
Group B Sample
Group C Sample
Mitochondrial activity assay
0.643 ± 0.154
0.682 ± 0.124
0.611 ± 0.173
0.692 ± 0.189
(MTT)
Lactate Dehydrogenase (LDH)
0.487 ± 0.094
0.503 ± 0.163
0.476 ± 0.120
0.511 ± 0.143
Total DNA Content
0.833 ± 0.144
0.789 ± 0.159
0.810 ± 0.201
0.805 ± 0.176
b-galactosidase
0.418 ± 0.067
0.512 ± 0.169
0.543 ± 0.112
0.498 ± 0.128
Chromosome Aberration
6.8%
5.88%
7.92%
6.73%
From the table above, we can observe that the Group A, B and C samples, the mitochondrial enzyme activity (MTT), lactate dehydrogenase (LDH), total DNA content, b-galactosidase and chromosome aberration are statistically consistent, and thus it shows that Group A, B and C samples do not contain cell poison and cause a change of chromosomes, and these samples have a good biocompatibility.
From the data as shown in the table, the main difference between the long-lasting collagen of the invention and the conventional collagen resides on that:
1. The invention complies with the novelty and improvement requirements of a patent application. In the present invention, the γ-polyglutarmic acid (γ-PGA) is added into a collagen and gone through a crosslinking process twice to obtain the long-lasting collagen, so as to overcome the shortcomings of the conventional collagen having a short storage time and requiring a frequent resupply of collagen by injection.
2. The invention complies with the practicability requirement of a patent application. In the present invention, glutaraldehyde of a low concentration goes through a crosslinking process twice to uniformly and completely crosslink the collagen with the glutaraldehyde to obtain a very low-concentration remained glutaraldehyde, while the long-lasting collagen has a better biocompatibility.
While the invention has been described by way of example and in terms of a preferred embodiment, it is to be understood that the invention is not limited thereto. To the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures. | In a long-lasting collagen and its manufacturing method, a pig skin is gone through processes of scraping extra tissues, removing fats, imbibition, digesting, centrifugal separation, salting-out, collecting lower-layer precipitate and freeze-drying to form a collagen, and the collagen is mixed with γ-PGA, and then a glutaraldehyde solution is added and mixed uniformly to perform a first crosslinking and form the long-lasting collagen, so as to overcome the shortcomings of a conventional collagen having a short storage time, a requirement of applying the collagen repeatedly, and a high concentration of remained glutaradldehyde which is biologically poisonous to human bodies. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates, in general, to subsea well apparatus and is directed specifically to subsea well apparatus such that, in only one trip between the vessel or platform on the water surface and the subsea well, a casing string is run into the well bore and cemented in place, a wear bushing is positioned within the well bore for protecting the surrounding wellhead during subsequent drilling operations, and the annular seal region between a casing hanger body and the surrounding wellhead bore is sealed and tested.
More specifically, in the drilling of oil and gas wells at an underwater location, a casing string is run into a well bore, and supported by a casing hanger (also referred to as hanger body) resting on complementary seats within a surrounding wellhead. After the casing string is cemented in place, a suitable seal assembly, referred to as a packoff assembly, is actuated (energized) to packoff (seal) the annular seal region (gland) between the exterior of the casing hanger and the surrounding wellhead for later drilling operations to take place within the wellhead. Energizing the packoff (seal) is also referred to as setting the packoff. Apparatus for such operations is illustrated in a number of U.S. patents, such as, for example, U.S. Pat. Nos. 3,313,030, 3,468,558, 3,468,559, 3,489,436, 3,492,026, 3,797,864 and 3,871,449. These patents show examples of casing hangers (hanger bodies), packoff assemblies with deformable elastomeric packing seals (packoffs), and seat protectors (now called wear bushings depending on their function, although in these patents, the terms were used interchangeably), being lowered into position in one trip of the running tool between the vessel or platform and the well.
Reference is also made to the U.S. patent application of Goris and Pettit, Ser. No. 719,383, filed Apr. 2, 1985 entitled "Casing Hanger and Running Apparatus", which disclosed apparatus in which seating the casing hanger within the wellhead, cementing the casing hanger in place, packing off the seal region and pressure testing off the seal for leakage is accomplished in one trip between the vessel or platform and the well. However, no wear bushing is disclosed in this referenced application.
Another U.S. patent application of John Pettit entitled "Casing Hanger Running Tool", Ser. No. 727,491, filed Apr. 26, 1985 discloses a running tool which, among other things, will position a casing hanger and a wear bushing in one trip with the wear bushing positioned in its final position upon the landing of the running tool in the wellhead.
This invention improves such apparatus by having a running tool engage one piece of a two piece wear bushing instead of engaging the casing hanger as in the prior art apparatus. The engaged piece supports a packoff drive nut of a packoff assembly which, in turn, supports a casing hanger. The other piece of the wear bushing is used to drive the packoff assembly to seal an annular seal region between the casing hanger and surrounding well bore. With this arrangement, one running tool is usable with varying sizes of casing hangers.
This invention also includes means by which the running tool can be released rapidly prior to moving the seal into the annular seal region and means by which an engaged piece of the wear bushing is positioned in its final operating position when the apparatus is initially landed in the well bore. Also included in the means for rapid release of the running tool is means for releasing the drive elements of the running tool upon application of low torque and a safety feature to prevent accidental release of the running tool.
SUMMARY OF THE INVENTION
This invention includes a running tool comprising a stem with a torque ring, a running nut, an engagement sleeve, and a lock ring, which together releasably connect and support a casing hanger, a two piece wear bushing, and packoff assembly thereon. The stem supports the lock ring which is externally profiled to engage complementary profiles on the first (inner) piece (referred to above as the engaged piece) of the wear bushing and is urged into engagement therewith by axial movement of the running nut upon rotation of the stem. The packoff drive nut of a packoff assembly, being threaded on external threads on the top of the casing hanger, supports the latter and is keyed to the second (outer) piece of the wear bushing for rotational movement therewith. The outer piece of the wear bushing is likewise keyed to the torque ring so that rotation of the torque ring also rotates the outer piece and the packoff assembly while the inner piece of the wear bushing remains stationary. In the process of rotating, the packoff nut becomes disengaged from the inner piece of the wear bushing.
Thus, this invention differentiates over all other such apparatus in that running tool engages one (inner) piece of the wear bushing which supports the packoff drive nut, the packoff drive nut, in turn, supports the casing hanger, and the other (outer) piece of the wear bushing drives the packoff assembly on rotation of the running tool.
The casing hanger, wear bushing and packoff assembly are lowered together into position within the wellhead on the running tool. In its initial landed position, the inner piece of the wear bushing is positioned without further movement being required. A flowby path is available during the circulating and cementing operations. After cementing has been completed, the running tool is released by rotation of the stem, which raises the running nut, disengages the engagement sleeve from the expanded lock ring and allows the lock ring to retract and disengage the inner piece of the wear bushing. Continued rotation raises the running nut to its upper most position where it becomes a driving element to rotate the torque ring and outer piece of the wear bushing to thread the packoff assembly downwardly off of the inner part of the wear bushing and into the annular seal region between the exterior of the casing hanger and the surrounding wellhead and to energize the packoff seal portion thereof to seal the annular seal region. The running nut is threaded on the stem with a thread having a significantly high angle thread lead (helix) of 10° to 15° for rapid axial movement so that the running nut will not jam when transmitting high torque. A dead band area between the engagement sleeve and running nut allows considerable amount of axial movement of the running nut before disengagement of the engagement sleeve from the lock ring as a safety feature against accidental disengagement of the running tool.
It will be apparent to those skilled in the art after a review of the drawings and the Detailed Description that in the arrangement of this invention:
(1) the same running tool may be used for various sizes of casing hangers without modification;
(2) the diameter of the inner bore (ID) of the inner piece of the wear bushing and the inner bore (ID) of the casing hanger are substantially the same so that wear of one or the other will not differ significantly during subsequent operations in the well:
(3) the high angle threads on the running nut and stem are effectively a releasable thread which allows high torque to be applied to the running nut in its driving position, but also allows the running nut to be backed off from its driving position with much less torque being applied to facilitate preparing the running tool for reuse; and
(4) the running tool is capable of being released, if desired, even through the packoff assembly has not been placed in proper sealing position, for whatever reason, to allow the running tool to be retrieved.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational view, in cross-section, illustrating the subsea well apparatus of this invention;
FIG. 2 is a cross-sectional view taken along line 2--2 of FIG. 1;
FIG. 3 is an elevational view, in cross-section, like FIG. 1, but taken along line 3--3 of FIG. 2;
FIG. 4 is an enlarged partial view taken along line 4--4 of FIG. 2 illustrating the releasable torque key connection between the packoff nut and wear bushing;
FIG. 5 is an enlarged partial view taken along line 5--5 of FIG. 1 showing the anti-rotation pin between the wear bushing and casing hanger;
FIG. 6 is an elevational view, in cross-section, like FIG. 1, but showing the packoff set;
FIG. 7 is an enlarged view of the packoff in the area of the arrow in FIG. 6; and
FIG. 8 illustrates a longer version of the wear bushing.
DETAILED DESCRIPTION
In the drawings, the invention is depicted already landed in the wellhead housing W with a casing hanger C shown supported on a suitable outwardly facing seat or shoulder (not shown) in the bore of the wellhead housing W. The casing hanger C, two piece wear bushing WB, and a packoff assembly P were assembled (made up) on a stem 10 of a running tool RT, while on the vessel or platform, and were lowered from the vessel or platform to the wellhead housing W by having the running tool stem 10 connected by a tapered thread connection 12 to the lower one of a string of tubing, such as drill pipe 14. The wear bushing WB comprises two pieces, a lower inner piece 16 and an upper outer piece 20 and as shown, a lower cylindrical section 24 of the inner piece 16 of the wear bushing WB is almost entirely nested in the casing hanger C and a second, thinner, upper cylindrical section 26 is seated on the top section 30 of the casing hanger C with the outer diameter of the upper section 26 the same as the outer diameter of the top section 30. The top section 30 of the casing hanger C and the upper section 26 are threaded on a packoff drive nut 32 of the packoff assembly P and, thus, are both supported by the packoff drive nut 32. Since the packoff drive nut 32 also supports the casing hanger C, when the apparatus is run into the wellhead W, it is also referred to as a running nut.
In the position shown, circulating and cementing operations can be conducted in the usual manner. After completion of the cementing operation, the annular seal space (gland) 34, between the cylindrical inner wall or bore of the wellhead housing W and the opposing cylindrical wall of the casing hanger C, is sealed by the packoff assembly P. This is accomplished by rotation of the outer piece 20 of the wear bushing WB driving the packoff assembly P into the annular seal space 34.
The running tool RT comprises the following components: the stem 10--a running nut 36, an engagement sleeve 40 and a lock ring 42; and near the middle and upper end of the stem--a torque ring 44 and stabilizing fins 46. The running tool RT with its attendant components are retrievable as will be understood from the description hereinafter.
The lower end of the stem 10 is also formed with an upset 50 (enlarged radial extension) which supports the lock ring 42. The lock ring 42 is provided with an external latching profile 52 for engaging a complementary internal latching profile 54 on the inner bore of the upper section 26 of the inner piece of the wear bushing WB. The lock ring 42 is a split ring, biased out of engagement with the profile 54, but is forced radially outwardly into engagement with the profile 54 by the engagement sleeve 40. This lock ring 42, when in engagement with the profile 54, enables the two pieces of the wear bushing WB and the packoff assembly P to be supported on the stem 10. The packoff assembly P, in turn, supports the casing hanger C. Retraction of the lock ring 42, on the other hand, not only permits initial assembly of the wear bushing WB and the equipment it supports on the running tool RT, but also allows disengagement of the running tool RT for retrieval at the appropriate time. FIG. 6 shows the position of the outer diameter of the lock ring 42, in its collapsed position, so as to allow retrieval of the running tool RT. The inner upper edge of the lock ring 42 and the lower end of the engagement sleeve are formed to facilitate their engagement.
The engagement sleeve 40 is a ring which rotates freely on the outer periphery of the stem 10 and is moved in and out of engagement with the lock ring 42, i.e., moved axially of the stem 10, by the running nut 36. The running nut 36 is an elongated sleeve with its lower end telescoped within the engagement sleeve 40 and, at its upper end, is provided with a radially outwardly extending rim 60 which is engagable with a radially inwardly extending rim 62 at the top of the engagement sleeve 40. The running nut 36 has internal threads 64 which engage complementary external threads 66 formed on the outer periphery of the stem 10 so that rotation of the stem 10 will also move the running nut 36 axially of the stem 10. The running nut 36 also has external keys 70 (one shown) which engage axial internal key slots 72 (also only one shown) on the torque ring 44 so that in one position, the running nut 36 may drive the torque ring 44 yet, in another position, move the running nut 36 axially relative to the torque ring 44. The keys 70 are fastened in grooves in the running nut 36 by bolts 76. Keys 70 are also the means which engage the top rim 62 of the engagement ring 40 to drive the latter behind the lock ring 42, as shown in FIG. 1.
The torque ring 44 is cylindrical with an inner bore spaced from the periphery of the stem 10 a distance sufficient to accommodate the running nut 36 and engagement sleeve 40 throughout most of its length and loosely engages the stem 10 by a radially inwardly directed flange 80. A split ring 82 bolted to the flange 80, and positioned within a groove 84 in the stem, prevents axial movement of the torque ring 44 relative to the stem 10. During assembly of the casing hanger C, two piece wear bushing WB and packoff assembly P on the running tool RT, this torque ring 44 is held stationary with respect to the casing hanger so that rotation of the stem 10 will thread the running nut 36 axially of the stem 10. Thus, rotation of the stem 10 to the left, i.e., counter clockwise, as viewed from the vessel or platform, will move the running nut 36 downwardly so that the running nut 36 will move the engagement ring 40 behind the lock ring 42 urging the external latching profile 52 into engagement with the internal latching profile 54. This is the position of the components in FIG. 1. As shown in FIG. 3, the torque ring 44 is provided with a position indicator in the form of a rod 90 located in a bore 92 in the flange 80. The rod 90 engages a threaded hole 94 on the running nut 36 and provides an indication that the lock ring 42 is fully engaged in the wear bushing profile.
The two sections 24 and 26 of the inner piece of the wear bushing WB form a bell-shaped body. As mentioned before, the lower section 24 is thicker than the upper section 26 and has a lower tapered surface 100 and an upper internal tapered surface 102 near the thinner upper section 26. Both tapered surfaces are generally parallel. The tapered surface 100 cooperates with a similarly tapered surface 104 on the casing hanger C and the upper tapered surface 102 cooperates with a tapered surface 106 on the upset 50 of the stem 10. The upper and lower sections 24 and 26 are also offset to receive the top section 30 of the casing hanger C in telescoping relationship. The upper section 26 is also provided with external threads 110 which threadably engage complementary internal threads 112 on the packoff drive nut 32.
The outer piece 16 of the wear bushing WB is an elongated sleeve which is slideable within the bore of the wellhead housing W and, as shown in FIGS. 1, 4 and 6, is provided with a plurality of downwardly extending torque keys 120 (lugs) which extend into complementary slots 122 in the top end of the packoff drive nut 32. By reason of this arrangement, rotation of the upper piece 16 will rotate the packoff drive nut 32. Within the torque keys 120 are frangible shear pins 124 biased outwardly by helical springs 126 into recesses 130 in the packoff drive nut 32. The shear pins 124 are held in place by a retainer 132. The torque keys 120, engaging the recesses 130, cause the upper piece of the wear bushing WB to follow the packoff nut as it is moved downward by action of the right hand threads, yet will shear when the wear bushing is to be retrieved.
The upper piece 16 of the wear bushing WB is also provided with internal axial key slots 134 formed in an internal rim 136 to receive elongated keys 140 (FIG. 2) positioned on the outer periphery of the torque ring 44. These keys 140 are located in a groove in the torque ring 44 and are fastened thereto by a plurality of bolts 142.
The lower end of the internal threads 112 on the packoff drive nut 32 which threadably engage complementary external threads 110 on the upper section 26 of the inner piece of the wear bushing WB also threadably engage external threads 150 on the top section 30 of the casing hanger C.
The depicted casing hanger C is typical and comprises a main body section 152 integral with the upper section 30 and provided with a cylindrical inner bore 154 and circulating passages 156 and a packoff actuating shoulder 160. As stated above, the external threads 150, located externally of the upper thin section 30 and shown in threaded engagement with internal threads 112 on the packoff drive nut 32, are right handed so that a right hand rotation of the upper piece of the wear bushing will lower the packoff drive nut 32 into the gland. As more clearly shown in FIG. 5, to prevent relative rotation between the casing hanger C and the inner piece 14 of the wear bushing WB, anti-rotation devices are provided. Each device is a pin 162 located in a vertical recess 164 in the lower edge of the upper section 26 and is biased by a helical spring 166 into a blind bore 170 in the very top edge of the thin section 30 of the casing hanger C. A retainer 172 holds the pin 162 and spring 166 within the recess 164.
Thus, as mentioned previously, counter clockwise rotation of the stem 10 will move the running nut 36 axially downwardly behind the engagement sleeve 40 to urge the lock ring 42 outwardly and into engagement with the upper section 26 of the inner piece of the wear bushing. Clockwise rotation of the stem 10, on the other hand, will thread the running nut 36 upwardly so that its rim 60 will eventually engage the rim 62 of the engagement sleeve 40 pulling the engagement sleeve 40 upwardly out of engagement with the lock ring 42, allowing the lock ring to release from the lower section 26 of the wear bushing. The dead band, or free axial movement of the running nut 36 upwardly for some distance before running nut rim 60 engages the rim 62, provides a safety factor against accidental release of the running tool for the casing hanger. Also, the key slots 72 on the torque ring 44, together with the high lead threads on the running nut 36 and stem 10, provide a rapid transport and thus rapid release of the running tool from the inner piece 14 of the wear bushing WB. The continued rotation of the stem 10 and continued upward movement of the running nut 36 will cause the top end of the keys 70 in the running nut 36 to engage the flange 80 on the torque ring 44. Since further rotation is prevented when the running nut 36 is in this position, the running nut 36 becomes a driving element whereby continued rotation of the stem 10 will drive the torque ring 44 to ultimately transmit rotational movement to the packoff drive nut 32. It is also pointed out that due to the high pitch of the threads, the running nut 36 will not be tightly engaged in its position against the flange 80 so that the running nut 36 can be easily broken out for further use of the running tool despite the high torque applied through the running nut 36 to set the packoff seal.
The packoff assembly P, as more clearly shown in FIG. 7, includes the packoff drive nut 32 and a packoff seal portion 174 connected to the packoff drive nut 32. The packoff seal portion is conventional, and more fully described in the U.S. Pat. No. 3,797,874, and in the U.S. patent application No. 4,521,040, it can be seen to include a swivel connection accomplished by a split retainer 176 ring mounted in a complementary grooves 180 in a support ring 182 and in the packoff drive nut 32. A thrust bearing 184 between the packoff drive nut 32 and the support ring 182 permits rotation of the packoff drive nut 32 without rotating the support ring 182. In the embodiment disclosed, the lower end of the support ring 182 engages and supports the upper end of a cylindrical resiliently deformable packing ring 186 by a dovetail connection 190. A lower abutment ring 192 is connected to the packing ring 186 by a dovetail connection 194.
Attention is now directed to FIGS. 1, 3 and 6 and to the top of the torque ring 44 and running tool stem 10.
The centralizer fins 46 are radially outwardly extending, relatively thin plates, each fixed, as by welding, at its lower end to a retainer ring 200 which surrounds and engages the torque ring 44. The upper end of the plates are each provided with a second retainer ring 202, attached as by welding thereto, surrounding and engaging the stem 10. Ring 202 is similar to ring 200, but has a split ring 204 seated in a groove 206 in the stem 10. Split ring 204 is attached to ring 202 by bolts 208. The ring/bolt assembly 202/208 attach the centralizer fins 46 to the torque ring 44 and stem 10. The centralizer fins 46 are L-shaped in elevation and extend radially outwardly to engage the inside surface of the wellhead housing 10 and serve to centralize the running tool within the wellhead housing W, as well as to act as a bushing between the stem 10 and the wellhead housing bore. A support ring 210 surrounds the fins 46 to provide a circular surface where the centralizer contacts the housing bore.
From the foregoing explanation and, as more clearly shown in FIG. 3, it can be seen that for circulating and cementing operations, there is a flowby through the passages 156 in the casing hanger, the annular seal area or gland 34, the passages 212 in the packoff drive nut 32, through ports 214 in the lower end of the outer piece 20 of the wear bushing, through axial slots 216 on the torque ring (see also FIG. 2 for slots 216) and out through the spaces between the centralizer fins 46. This flow is represented by the arrow 220 in FIG. 3.
Again, after the circulating and cementing operations, clockwise rotation of the stem 10 will first cause upward movement of the running nut 36 on the threads 66 and, afterward, a downward movement of the packoff assembly P by reason of rotation of the running nut 36, torque ring 44 and outer piece 20 of the wear bushing. Continued rotation of the stem 10 will cause the packoff drive nut 32 to drive the seal assembly downward free and clear of the threads 110 on the upper section 26 of the inner piece of the wear bushing and into engagement with the shoulder 160 on the casing hanger and to expand the elastomeric seal 186, thus sealing the annular seal area 34 against leakage. This is depicted in FIG. 7. The lower abutment ring 192 also engages a conical surface 222 on a split ring 224 to urge the latter into a groove 224 in the wellhead housing W to lock the casing hanger C within the well bore. The split ring 224 is supported on a ring 230 threaded on the casing hanger C.
It should be noted that as the outer piece 20 of the wear bushing WB is rotated downward, relative to the inner piece 16, the flowby ports 214 become blanked off by the top of the inner piece. This prevents debris and cuttings from accumulating on the bore of the wellhead.
At this time, the efficacy of the seal of the set packoff 186 is tested by pressurizing the area above the running tool, etc. The O-ring seals 232 between the casing hanger C and section 24 of the inner piece 16 of the wear bushing (three seals shown) and O-ring seals 234 between the thin section 26 of the inner piece 16 and the upset 50 on the stem 10 (two shown) prevent leakage between these named components so that the seal of the set packoff can be tested.
It should be pointed out also at this time that rotation of the packoff drive nut 32 could begin before the running nut 36 reaches its uppermost position due to friction, debris, etc., causing the torque ring 44 and upper piece 20 of the wear bushing to rotate, but, in any event, as the packoff assembly P begins to set, this frictional phenomena will be overcome and the running nut 36 will continue to thread upwardly until it reaches its uppermost position engaging the flange 80 where it becomes a drive element. The ability of the running tool to be released prior to the setting of the packoff also has the advantage of retrieving the running tool in the event the packoff cannot be properly set for whatever reason.
The running nut 36, in the meantime, has freed the lock ring 42 of engagement with the inner piece 16 of the wear bushing so that the torque ring 44, running nut 36, engagement sleeve 40, and lock ring 42 are now free to be withdrawn.
As shown in the drawings, the inner bore 240 of the inner piece 16 of the wear bushing WB and the bore 154 of the casing hanger C are substantially the same so that wear during subsequent operations on the well will be distributed between the two bores. FIGS. 1 and 8 also show the universality of the running tool for different sizes of wear bushings and casing hangers. Conventionally, the casing hanger C above the main body section 152 at about line A remains the same so that the different size casing hangers differ only in diameter of the inner bore 154 of the main body section 152. In FIG. 1 two such differences in sizes of casing hangers are illustrated in phantom at 154a and 154b. Similarly, the inner piece 16 of the wear bushing WB will be made to correspond to the inner diameter of the selected casing hanger by thickening the wall of the lower section 24 and extending the tapered surfaces 100 and 102. Thus, the bore of the thickened lower section will correspond in diameter to the selected bore of the casing hanger as at 240a and 240b. No change needs to be made in the length of the tapered surface 106 on the upset 50 of the stem 10.
FIG. 8 illustrates another configuration of the two piece wear bushing WB for larger bore casing hangers with longer wear bushings. The inner piece 16b and outer piece 20b differ in thickness and length from the previously described pieces of the wear bushing and are given the same reference numerals, but with the suffix b to denote their similar functions. This configuration, however, has additional flowby slots 244. The running tool RT will handle this configuration of the wear bushing without modification.
The wear bushing WB may be removed by the same running tool RT in the same manner that the apparatus was originally assembled. As shown in FIG. 6, the packoff drive nut 32 is now free of the external threads 112 on the top section 26 of the inner piece 16 and the running nut 32 is threaded on the casing hanger C. Thus, a pull on the running tool RT will move the inner piece 16 upwardly, free of the casing hanger, so that its top end 250 engages the rim 134 and both pieces of the wear bushing WB will then be retrievable. At this time, since the outer piece 20 is still latched to the top of the running nut 36 by shear pins 124 (FIG. 4), the continued pull on the wear bushing will shear these pins freeing the wear bushing WB of the packoff drive nut 32.
To re-run the wear bushing WB, there are two possible methods available. One method is to lower the wear bushing WB utilizing the same running tool RT. Another method is to engage J-slots 252 on the inner bore of the outer piece 20 of the wear bushing WB with any running tool having J-slot lugs thereon. In the second method, the two pieces of the wear bushing WB must be fastened together by any suitable means, such as by bolts through the outer piece engaging threaded bores in the inner piece. | A running tool (RT) comprising a stem (10) with a torque ring (44), a running nut (36), an engagement sleeve (40), and a lock ring (42) to releasably connect and support a casing hanger (C), a two piece (16,20) wear bushing (WB) and packoff assembly (P) thereon. The lock ring (42) is wedged into engagement with one piece (16) of the wear bushing (WB) by downward axial movement of the running nut (36). The casing hanger (C) is threaded on the packoff assembly (P) and supported thereby and arranged so that rotation of the torque ring (44) and stem (10) rotates another piece (20) of the wear bushing (24) and the packoff assembly (P) to set the packoff.
The casing hanger (C) and one piece of the wear bushing (WB) are lowered on the running tool (RT) into final position within the wellhead (W). The running tool (RT) is released by rotation of the stem (10) which raises the running nut (36), disengages the engagement sleeve (40), allowing the lock ring (44) to disengage the wear bushing (WB). A dead band between the engagement sleeve (40) and running nut (36) prevents accidental release of the running tool (RT) from the wear bushing (WB), and, on further rotation, the running nut (36) becomes a driving element for piece (20) of the wear bushing (WB) and for threading packoff drive nut (32) of the packoff assembly (P) so as to set the packoff. During rotation, the packoff nut (32) becomes disengaged from piece (16) of the wear bushing (WB).
The apparatus is characterized by not having the lock ring (42) engage the casing hanger (C) and in that one running tool is usable with several sizes of casing hangers. | 4 |
BACKGROUND OF THE INVENTION
[0001] 1. Technical Field
[0002] The present invention relates to a fiber composite twisted cable and, more specifically, to a twisted cable in which carbon fibers and thermosetting resin as a matrix are combined.
[0003] 2. Description of the Related Art
[0004] Among high-strength low ductility fibers, carbon fibers have characteristics such as light weight, high corrosion resistivity, non-magnetic property, high coefficient of thermal conductivity, ultralow coefficient of thermal expansion, high tensile strength, and high tension modulus. In order to make full use of such characteristics, a fiber composite twisted cable having carbon fibers and thermosetting resin as a matrix combined to each other is known.
[0005] The fiber composite twisted cable is manufactured generally by forming strands by twisting bundles of carbon fibers impregnated with thermosetting resin, twisting a plurality of such strands, and then curing the thermosetting resin by heat treatment.
[0006] However, there is a problem such that air or residual solvent contained in thermosetting resin remains in the interior of a cable as gaps between a process of impregnating with the thermosetting resin and a process of forming a cable by twisting the plurality of strands, whereby mechanical characteristics such as the tensile strength per cross-sectional area of the cable, which is important characteristics as the fiber composite twisted cable is lowered.
[0007] Accordingly, in JP-A-2-127583, a fiber composite twisted cable formed by winding a fiber yarn on an outer periphery of a strand impregnated with thermosetting resin at an angle close to a right angle with respect to the axial direction of the strand in high density, then twisting a plurality of the strands, and then curing the thermosetting resin by heat treatment is proposed.
[0008] According to the related art, the fiber bundles are prevented from being unlaid by winding the fiber yarn, and an effect of expelling the air or the residual solvent contained in the interior of the cable is expected by a winding pressure of the fiber yarn. However, when twisting the plurality of strands impregnated with the thermosetting resin, liquid-state thermosetting resin in an uncured state is squeezed out from between the wound fiber yarns, so that the resins from adjacent side strands moisten with respect to each other, and flows into a gap between a core strand and the side strands and stays therein.
[0009] Therefore, when the thermosetting resin is cured in a last process, the adjacent strands are adhered and integrated with each other (the core strand and the side strands, and the side strands and the side strands), so that the entire cable becomes cured like a hard rod.
[0010] Therefore, bending rigidity of the fiber composite twisted cables in the related art is very high and, consequently, flexibility that the cable should have under normal circumstances by having a twisted wire structure is impaired, and hence a large reel provided with a large-diameter winding barrel is required.
[0011] Consequently, when applying the fiber composite twisted cable to a reinforcing member for an overhead transmission line and performing a wiring work in a mountain range for example, problems in transport such that a large vehicle for loading the large reel is required and, road works for moving the large vehicle in turn are required are inevitable.
[0012] Furthermore, when winding the fiber composite twisted cable on the reel, partial separation of the thermosetting resin which bonds the strands with respect to each other occurs by bending, so that bonded portions and separated portions exist together between the adjacent strands in the longitudinal direction of the cable. Consequently, there arises a problem such that bending occurs when the cable is withdrawn from the reel when using the cable and hence linearity of the cable is impaired.
SUMMARY OF THE INVENTION
[0013] In order to solve the above-described problems as described above, the fiber composite twisted table in the related art is improved, and it is an object of the invention to provide a fiber composite twisted cable having preferable flexibility and being superior in transportability and workability suitable for being used as a reinforcing member for a high-voltage transmission line or a tensile strength reinforcing member for concrete structures such as a bridge girder.
[0014] In order to achieve the above described object, a fiber composite twisted cable according to an embodiment of the invention is a cable having 1×n structure which is formed by impregnating bundles of carbon fibers with thermosetting resin, then twisting a plurality of strands each formed by covering an outer periphery of the bundle with a fiber, and then curing the thermosetting resin by heat treatment, and is characterized in that a core strand and side strands surrounding the same, which constitute the 1×n structure, are in contact with each other separately and independently without being bonded to each other so as to allow the respective strands to perform independent behaviors when the cable is bent at a right angle with respect to the longitudinal direction. With the fiber composite twisted cable according to the invention, the respective strands which constitute the cable are separately and independently in contact with each other without being bonded to each other, and minute gaps for allowing the independent behaviors when the cable is bent in the direction at a right angle with respect to the longitudinal direction thereof are formed between the core strand and the side strands surrounding the same. Therefore, a constraining force is suitably alleviated by a slipping effect between the adjacent strands, whereby the flexibility required for the cable is improved.
[0015] Since deformation of the strands due to a bending stress applied to the cable is facilitated by the gaps surrounded by the side strands and the core strand secured therein, the flexibility is further improved.
[0016] Therefore, according to the embodiment of the invention, since the flexibility of the cable is improved, winding of the cable around the reel, which is inevitable when manufacturing a long cable or transporting the cable as a product, can be performed without problem, and the barrel diameter of the reel can also be reduced.
[0017] Therefore, when it is used as the reinforcing member for the high-voltage transmission line or the tensile strength reinforcing member for the concrete structure such as a bridge girder, transport of the cable to the mountain range or the mountain area is facilitated, and a transport cost can be reduced.
[0018] Since the cable can be wound around the reel without problem, generation of abnormal residual stress on the cable is avoided, and formation of curl is avoided even when the cable is withdrawn from the reel when using the same. The cable withdrawn from the reel is easy to handle, allows measurement of the cable length with high degree of accuracy on site, and allows easy terminal process. Therefore, the workability is improved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1A is a perspective view showing a first embodiment of a fiber composite twisted cable according to the invention;
[0020] FIG. 1B is a vertical cross-sectional front view of the first embodiment;
[0021] FIG. 1C is a partial enlarged view of FIG. 1B ;
[0022] FIG. 2A is a perspective view showing a state in which the fiber composite twisted cable according to the first embodiment is about to be put asunder;
[0023] FIG. 2B is a perspective view of the fiber composite twisted cable shown in FIG. 2A after having put asunder;
[0024] FIG. 3 is an explanatory drawing showing a process of manufacturing a prepreg by impregnating a multifilament formed of carbon fibers with thermosetting resin;
[0025] FIG. 4 is an explanatory drawing showing a process of manufacturing a covered composite strand;
[0026] FIG. 5 is an explanatory drawing showing a process of manufacturing a composite twisted cable in a semi-cured or uncured state by twisting the covered composite strands;
[0027] FIG. 6 is an explanatory drawing showing a heat treatment process;
[0028] FIG. 7A is a perspective view showing a fiber composite twisted cable after having finished the heat treatment;
[0029] FIG. 7B is a cross-sectional view of the fiber composite twisted cable after having finished the heat treatment;
[0030] FIG. 7C is a partial enlarged view of FIG. 7B ;
[0031] FIG. 8A is a side view showing an apparatus and a process of separating the strands of the fiber composite twisted cable;
[0032] FIG. 8B is a cross-sectional view taken along the line X-X in FIG. 8A ;
[0033] FIG. 9A is a perspective view showing a second embodiment of a fiber composite twisted cable according to the invention;
[0034] FIG. 9B is a cross-sectional view showing a state before strand separation according to the second embodiment;
[0035] FIG. 10A is a perspective view showing a third embodiment of a fiber composite twisted cable according to the invention;
[0036] FIG. 10B is a cross-sectional view showing a state before strand separation according to the third embodiment;
[0037] FIG. 11A is a drawing of a state in which power cables are strung showing an example in which the fiber composite twisted cable according to the embodiment of the invention is applied to a reinforcing member of the a high-voltage transmission line;
[0038] FIG. 11B is a partially cut-out side view of the power cable shown in FIG. 11A ;
[0039] FIG. 11C is a cross-sectional view of the power cable shown in FIG. 11B ;
[0040] FIG. 12A is a perspective view of a bottom of a bridge showing an example in which the fiber composite twisted cables according to the embodiment of the invention are applied to tensile strength reinforcing members of a concrete bridge girder; and
[0041] FIG. 12B is a bottom view of the bridge girder in a tensed state.
DETAILED DESCRIPTION OF THE INVENTION
[0042] Referring now to the attached drawings, an embodiment of the present invention will be described.
[0043] FIG. 1A to FIG. 2B show a fiber composite twisted cable having 1×7 structure according to an embodiment of the invention. Reference numeral 1 designates an entire fiber composite twisted cable (hereinafter, referred to simply as “cable”), having a diameter of 12 mm, for example. Reference numerals 21 , 22 are strands which constitute the cable 1 . The cable 1 includes seven strands having the same thickness. Six side strands 22 are arranged around a single core strand 21 , and these strands are twisted together.
[0044] The core strand 21 and the side strands 22 are formed by binding or twisting a plurality of prepregs 2 ′, which are formed by impregnating respective bundles of PAN (polyacrylonitrile) carbon fibers 2 with thermosetting resin 3 as shown in FIG. 1C . Also, the outer periphery of the each strand is covered with a fiber yarn 4 wound therearound at an angle close to a right angle with respect to the axial direction of the strand in the high density. The “yarn” here is a concept including a tape.
[0045] The core strand 21 and the six side strands 22 are covered with the fibers, and are twisted with the thermosetting resin contained therein uncured and hence are formed into the uncured fiber composite twisted cable. Then, the uncured fiber composite twisted cable is subjected to heat treatment so that the thermosetting resin is cured.
[0046] However, in the embodiment of the invention, the adjacent side strands 22 and 22 are not bonded to each other, and the side strands 22 and the core strand 21 are not bonded to each other, that is, the respective strands are separated and independent and are only in contact with each other in the longitudinal direction.
[0047] Therefore, five gaps 5 in substantially a triangle shape, where the thermosetting resin is not present, are formed in a portion surrounded by the core strand 21 and the two side strands 22 and 22 in the embodiment as shown in FIG. 1B , and the gaps 5 function as spaces for allowing independent behaviors of the strands when the cable is bent in the direction at a right angle with respect to the longitudinal direction.
[0048] FIGS. 2A and 2B show the fiber composite twisted cable being put asunder. The single core strand 21 at the center and the six side strands 22 positioned therearound exist separately and independently respectively at a regular helical pitch. The separate and independent relationship between the core strand 21 an the side strands 22 is realized by performing a separation process which forcedly releases a bonded state of the respective strands after the heat treatment, that is, after having cured the thermosetting resin.
[0049] More specifically, in a manufacturing process, the core strand 21 and the six side strands 22 are twisted in the state in which the thermosetting resin contained therein is uncured or semi-cured. The thermosetting resin is extruded out from between the fiber yarns 4 on the outer peripheries of the respective strands by a pressure applied by this twisting action, and wets the adjacent side strands 22 with respect to each other. It also wets the periphery of the core strand 21 , so that the gaps around the side strands 22 and the core strand 21 are filled with the thermosetting resin. In this state, heat is applied and the thermosetting resin is cured, so that the adjacent side strands 22 and 22 are integrally bonded to each other and the side strands 22 and 22 and the core strand 21 are also bonded to each other.
[0050] Normally, the fiber composite twisted cable is considered to be a finished product in the state described above. However, according to the embodiment of the invention, the integrally bonded side strands 22 and 22 , and the side strands 22 and 22 and the core strand 21 are separated after the heat treatment into independent individual strands and, in this state, these strands are twisted again into the original state. The separating process is performed after the thermosetting resin is cured and stabilized. Therefore, the adjacent side strands 22 and 22 and the core strand 21 are never bonded to each other again.
[0051] Since the core strand 21 and the side strands 22 are separated and independent, when a bending stress is applied to the cable 1 , the side strands 22 can be moved in their own about the core strand 21 . Therefore, bending rigidity is smaller than that of a bar (rod) having the same diameter, so that higher flexibility is resulted.
[0052] Since the substantially triangle gap 5 per unit, which is surrounded by the core strand 21 and the two side strands 22 and 22 allow the side strands 22 to run off on the tensed side and the compressed side when being bent. Therefore, the cable 1 can easily be bent and the residual stress is also alleviated.
[0053] Subsequently, the manufacturing process of the fiber composite twisted cable 1 according to an embodiment of the invention will be described in detail.
[0054] FIG. 3 shows a process for obtaining the strand. A multifilament 30 including 12000 carbon fibers having a diameter of 7 μm, for example, and being aligned in parallel are wound around a reel 31 . The multifilament 30 is withdrawn from the reel 31 , is guided to a resin bath 35 via a guide roll 32 , and is allowed to submerge through the thermosetting resin 3 , for example, modified epoxy resin, stored therein, and the multifilament 30 is impregnated with the modified epoxy resin.
[0055] The multifilament 30 impregnated with the modified epoxy resin is introduced into a dice 33 , and excessive modified epoxy resin is pressed and removed, and is formed into a circular shape in cross-section. Then, the multifilament 30 is passed through a drying furnace 36 to semi-cure the thermosetting resin to form a prepreg (element wire) 38 , which is wound around a reel 39 . The prepreg may be kept in uncured state by omitting or stopping operation of the drying furnace 36 .
[0056] Subsequently, a number of, for example, fifteen prepregs 38 manufactured in the previous process, not shown, are bundled and twisted at a large pitch, for example, 90 mm, so that a composite element strand is obtained. In this process, for example, fifteen reels 39 having the prepreg 38 wound therearound are arranged on a stand, the fifteen prepregs are withdrawn and bundled into the composite element strand and are twisted by turning the reel in the direction at a right angle with respect to a movement path while winding the same together on a reel.
[0057] The modified epoxy resin is used when the heat resistance on the order of 130° is required. When the heat resistance as high as 240° is required, Bismaleimide resin is used.
[0058] FIG. 4 shows a formation of the strand and a covering process, in which reference sign b designates a covering device. A reel 40 having a composite element strand 381 manufactured in the previous process wound therearound is mounted on a supporting shaft 401 of the covering device b.
[0059] The covering device b is provided with a winding machine 45 around the movement path of the composite element strand, and the fiber yarn 4 is wound around the winding machine 45 . Multifilament yarn formed of multipurpose fiber such as polyester fiber is suitable as the fiber yarn and, for example, that having 8 yarns of 1000 denier is exemplified.
[0060] The composite element strand 381 is wound by a strand reel 49 via a guide roll 42 , and the winding machine 45 is turned around the composite element strand 381 in the course of movement to wind the fiber yarn 4 on an outer periphery of the composite element strand 381 to cover the outer periphery at an angle close to a right angle with respect to the axial direction, for example, at 60 to 85 degrees in the high density. Consequently, a covered composite strand 50 is manufactured.
[0061] The purpose for covering the periphery of the strand with the fiber is to bundle the composite element strand 381 and prevent the same from being deformed or unlaid at the time of twisting. Another purpose is to discharge and remove the excessive thermosetting resin or solvent which the strands are impregnated with, or air bubbles which may cause the strength of the cable to be lowered or the like by a winding pressure.
[0062] Subsequently, the seven strand reels on which the covered composite strands 50 are wound are mounted on a twisting device c shown in FIG. 5 .
[0063] The twisting device c includes one strand reel 491 on which a strand which becomes the core strand is wound, and six strand reels 492 on which strands which become the side strands arranged therearound. The six strand reels 492 for the side strands are rotated around the single composite strand 50 which becomes the core strand, the six covered composite strands 50 ′ which become the side strands are twisted and are passed through a voice 51 while being pulled by a capstan 52 , so that the thermosetting resin is wound around a reel 59 as a composite twisted cable 60 in the state in which the thermosetting resin is semi-cured or uncured.
[0064] Subsequently, the reel 59 on which the uncured composite twisted cable 60 is wound is arranged in a heat treatment device d shown in FIG. 6 , and the uncured composite twisted cable 60 is passed through a heater 65 under the conditions of, for example, 130° C. and 90 minutes, the semi-cured or uncured thermosetting resin is completely cured, and a cured composite twisted cable 90 is wound around a reel 69 .
[0065] A semi-cured or uncured thermosetting resin 300 contained in the composite strand of the cured composite twisted cable 90 is exuded from the gaps between the fiber yarns in the initial stage of heating. The respective gaps surrounded by a core strand 91 and side strands 92 , 92 is filled with the exuded thermosetting resin 300 and the thermosetting resin 300 filled in the respective gaps is cured in the latter half of the heating period. Therefore, as shown in FIG. 7A to FIG. 7C , the core strand 91 and the side strands 92 are integrally bonded. Since the troughs between the adjacent side strands 92 , 92 are also filled with the thermosetting resin 300 , the side strands 92 , 92 are also bonded to each other.
[0066] The form as described above is unavoidable in the fiber composite twisted cable in the related art. The inventors thought of applying the heat treatment on the composite strands 50 , 50 ′ manufactured in the process shown in FIG. 4 , forming the strands whose thermosetting resin contained therein is cured, and twisting these hard covered strands into a cable as a measure for improving the flexibility. However, since the hard covered strands are already in the state of hard rods, it is very difficult to bundle seven such hard strands and twist the same into the helical shape. In addition, since the thermosetting resin in the strands is separated during twisting and hence the function as the matrix is impaired, it is not suitable.
[0067] Accordingly, in the invention, the core strand 91 and the side strands 92 , which are bonded and cured with the thermosetting resin exuded into the gaps surrounded by the core strand 91 and the side strands 92 , 92 are separated (unstuck) from each other using specific means and process. The bonding between the side strands 92 is also separated (unstuck) from each other.
[0068] FIG. 8A and FIG. 8B show the process and the device therefor. A strand separating device e includes a rotatable separation plate 70 , and a separation voice 75 and the binding voice 76 are positioned on the downstream side and the upstream side of the separation plate 70 , respectively. The separation plate 70 is formed of a circular metallic plate and includes a core strand insertion hole 73 for insertion of the core strand 91 of the cured composite twisted cable 90 at the center thereof and a plurality of side strand insertion holes 74 arranged radially from the core strand insertion hole 73 apart from each other uniformly. In this example, there are provided the six side strand insertion holes 74 .
[0069] The separation of the core strand 91 and the side strands 92 are performed as follows. In other words, the cured composite twisted cable 90 wound around the reel 69 is inserted through the separation voice 75 , a terminal end of the inserted cured composite twisted cable 90 is unlaid into individual strands. The core strand 91 is inserted through the core strand insertion hole 73 of the separation plate 70 , and the six side strands 92 are inserted respectively through the side strand insertion holes 74 .
[0070] Then, the strands 91 and 92 passed through the separation plate 70 are introduced into the binding voice 76 , and are guided to a reel 80 via a capstan 79 . At this time, the separation plate 70 is rotated in the direction opposite from the direction of twisting of the cured composite twisted cable 90 in conjunction with a speed of pulling out the cured composite twisted cable 90 .
[0071] With this process, the core strand 91 and the side strands 92 of the cured composite twisted cable 90 are separated and the side strands are separated from each other, and hence the bonded state is released. Therefore, the unstuck independent strands are restored to “1×7” twisted relationship in the binding voice 76 , and hence is withdrawn as the fiber composite twisted cable 1 according to the embodiment of the invention in FIG. 1 and is wound around the reel 80 .
[0072] The fiber composite twisted cable 1 is improved in flexibility because the gaps, which allow the independent behaviors of the respective strands 21 , 22 when the cable is bent, are formed between the core strand 21 and the side strands 22 surrounding the same, which constitute the cable, as shown in FIG. 1 and FIG. 2 , so that the reel 80 may be downsized in diameter of the barrel and the flange in comparison with the reel for winding the cured fiber composite twisted cable 90 in the related art. Therefore, the style of packaging is downsized and the weight is reduced, so that easy transport is achieved.
[0073] Referring now to the attached drawings, a second embodiment of the invention will be described.
[0074] FIG. 9A shows a fiber composite twisted cable 100 having a structure of 1×19 including nineteen strands, and having a diameter of 18 mm according to the second embodiment of the invention. The composite twisted cable 100 is configured as described in the first embodiment, and the strands are separated and independent without being bonded to each other so that gaps for allowing independent behaviors of the respective strands when the cable is bent are formed between a core strand and side strands surrounding the same.
[0075] The composite twisted cable 100 includes a single core strand 111 and six first layer strands 112 twisted so as to surround the core strand 111 , and also includes twelve second layer strands 113 twisted on an outer periphery thereof.
[0076] The respective strands 111 , 112 and 113 have a configuration including a plurality of twisted prepregs, which are formed of bundles of PAN carbon fiber impregnated with thermosetting resin as in the first embodiment, and outer peripheries of the strands are covered with a fiber yarn 400 wound therearound at an angle close to a right angle with respect to the axial direction of the strand in the high density.
[0077] Reference numerals 500 designate five substantially triangle shaped gaps surrounded by the core strand 111 and the first layer strands 112 and 112 . By the existence of the gaps, the first layer strands 112 and 112 , and the core strand 111 are separated and independent and are only in contact with each other in the longitudinal direction without being bonded to each other. The adjacent first layer strands 112 and 112 are also separated and independent in the longitudinal direction without being bonded to each other.
[0078] Reference numerals 501 designate six substantially crescent-shaped gaps surrounded by the first layer strands 112 and the second layer strands 113 , and the first layer strands 112 and the second layer strands 113 are separated and independent and are only in contact with each other in the longitudinal direction without being bonded to each other. The adjacent second layer strands 113 and 113 are also separated and independent and are only in contact with each other in the longitudinal direction without being bonded to each other.
[0079] The gaps 500 , 501 function as spaces which allow independent behaviors of the strands when the cable is bent in the direction at a right angle with respect to the longitudinal direction of the cable.
[0080] The manufacturing process will be described, the core strand 111 , the first layer strands 112 , and the second layer strands 113 after having covered with the fiber yarns are twisted into an uncured fiber composite twisted cable in a state in which the thermosetting resin contained therein is not cured, and the thermosetting resin is cured by applying the heat treatment on the uncured fiber composite twisted cable, whereby a semi-finished product as shown in FIG. 9B is obtained. At this time, as in the case of the first embodiment, the core strand 111 and the first layer strands 112 are integrally bonded with the exuded liquid-state thermosetting resin 300 , and the first layer strands 112 and the second layer strands 113 surrounding the same are integrally bonded with the exuded liquid-state thermosetting resin 300 .
[0081] In order to obtain the above-described composite twisted cable 100 , as in the case of the first embodiment, it is forcedly unstuck using a separating device to release the bonded state. Other points are the same as described in the first embodiment.
[0082] Referring now to the attached drawings, a third embodiment of the invention will be described.
[0083] FIG. 10A shows a fiber composite twisted cable 200 having a structure of 1×37 including thirty seven strands, and having a diameter of 28 mm according to a third embodiment of the invention.
[0084] The cable 200 includes a single core strand 211 and six first layer strands 212 twisted so as to surround the core strand 211 , includes twelve second layer strands 213 twisted on an outer periphery thereof, and further includes eighteen third layer strands 214 twisted on the outer periphery thereof.
[0085] Reference numerals 500 designate five substantially triangle shaped gaps surrounded by the core strand 211 and the first layer strands 212 and 212 . By the existence of the gaps, the first layer strands 212 and 212 , and the core strand 211 are separated and independent and are only in contact with each other in the longitudinal direction without being bonded to each other.
[0086] Reference numerals 501 designate six substantially crescent-shaped gaps surrounded by the first layer strands 212 and the second layer strands 213 , and the first layer strands 212 and the second layer strands 213 are separated and independent and are only in contact with each other in the longitudinal direction without being bonded to each other. The adjacent second layer strands 213 and 213 are also separated and independent without being bonded to each other and are in contact with each other in the longitudinal direction.
[0087] Reference numerals 502 designate a number of diamond-shaped gaps surrounded by the second layer strands 213 and the third layer strands 214 . With these gaps, the second layer strands 213 and the third layer strands 214 are separated and independent and are in contact with each other in the longitudinal direction without being bonded to each other. The adjacent third layer strands 214 and 214 are also separated and independent without being bonded to each other and are in contact with each other in the longitudinal direction. The gaps 500 , 501 and 502 function as spaces which allow independent behaviors of the strands when the cable is bent in the direction at a right angle with respect to the longitudinal direction of the cable.
[0088] The core strand 211 , the first layer strands 212 , the second layer strands 213 and the third strands 214 after having covered with the fiber yarns are twisted into an uncured fiber composite twisted cable in a state in which the thermosetting resin contained therein is not cured, and the thermosetting resin is cured by applying the heat treatment on the uncured fiber composite twisted cable, whereby a semi-finished product as shown in FIG. 10B is obtained. At this time, as in the case of the first embodiment, the core strand 211 and the first layer strands 212 are integrally bonded with the exuded liquid-state thermosetting resin 300 , and the first layer strands 212 and the second layer strands 213 surrounding the same, and the second layer strands 213 and the third layer strands 214 surrounding the same are integrally bonded with the exuded liquid-state thermosetting resin 300 .
[0089] In order to obtain the above-described composite twisted cable 200 , as in the first embodiment described above, it is forcedly unstuck using the separating device to release the bonded state of the strands with respect to each other. Other points are the same as described in first embodiment.
[0090] FIGS. 11A , 11 B and 11 C show examples in which the fiber composite twisted cable according to the embodiment of the invention is used as a reinforcing member for an overhead transmission line. High-voltage transmission lines B extended between steel towers A in FIG. 11A have a structure as shown in FIG. 11B and FIG. 11C . In other words, the fiber composite twisted cable 1 in the first embodiment is used as a core member, and aluminum lines or heat-proof aluminum alloy wires 900 are arranged in two layers and twisted on the periphery thereof.
[0091] FIGS. 12A and 12B show examples in which the fiber composite twisted cable according to the embodiment of the invention is applied to a reinforcing member of a concrete structure. In order to reinforce a bridge girder C, the fiber composite twisted cables 1 , 100 , or 200 according to any one of the first to the third embodiments are extended between the bridge girders C provided at both ends in the longitudinal direction, and a tonicity is applied thereto using a fixing member.
[0092] The fiber composite twisted cable according to the embodiments of the invention is applied also to cables for a suspension bridge or ground anchors. | The invention relates to a composite twisted cable formed by impregnating carbon fibers with thermoplastic resin, and provides a fiber composite twisted cable which allows downsizing of a reel by being easy to be bent, can be transported to mountain areas which is normally hard to achieve a transport with a large vehicle, is hard to be curled, and is superior in workability. It is a cable having 1×n structure which is formed by impregnating bundles of carbon fibers with thermosetting resin, then twisting a plurality of strands each formed by covering an outer periphery of the bundle with a fiber, and then curing the thermosetting resin by applying the heat treatment, and a core strand and side strands which constitute the cable are separated and independent without being bonded so as to allow independent behavior of the respective strands when the cable is bent. | 3 |
RELATED APPLICATIONS
This is a Divisional Application which is based on U.S. Ser. No. 12/882,031, filed on Sep. 14, 2010; which is a continuation of U.S. Ser. No. 11/736,434, filed on Apr. 27, 2007, now U.S. Pat. No. 7,837,428, issued on Nov. 23, 2010; which claims benefit of U.S. Provisional Application No. 60/893,022, filed on Mar. 5, 2007.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to methods and apparatuses for loading bulk material into containers. More particularly, the invention relates to methods for loading scrap metal and steel into freight containers, and apparatuses thereof.
2. Description of the Related Art
Efficiency and speed are important in the freighting industry. Decreasing the time necessary to load material into a freight container, transport the container, and unload the material from the container usually translates into greater profits for those involved in the process. One way the industry has increased efficiency has been to standardize the sizes of its freight containers, as defined by the ISO 668 standard. The use of standard sized freight containers allows tractor-trailers, ships, trains, and other freight carriers to quickly load and unload containers and to optimally utilize their available space. While freight containers come in several standard sizes, the most common sizes are the standard 40′, the 40′ high-cube, and the standard 20′. The minimum internal height of most ISO standard shipping containers is 7′ 8½″, while the minimum internal width is 7′ 7¾″.
The use of such standard internal minimum dimensions generally permits quick loading and unloading of standard sized pallets onto freight containers while maximizing the use of available space in the containers. Not all materials, however, are suitable for palletization. For instance, bulk material, such as scrap metal, generally should not be palletized because such material varies widely in shape. As a result, many pieces of the bulk material are too large to fit within a pallet and must be either loaded separately into the container or cut into smaller pieces. Even when the bulk material is small enough to fit within a pallet, the space in the pallet is generally severely underutilized because of the bulk material's irregular shape. Because of the problems associated with palletizing bulk material, other methods for loading bulk material into freight containers have been developed.
One method to load bulk into a freight container is to use a conveyer belt. In this way, bulk material is placed on a conveyer belt that leads from outside of the container, through a door in the container, and terminates at an opposite closed end of the container. When the material reaches the end of the conveyer belt, it falls off the belt and is thus placed in the container. There are several problems with this method. First, the size of the conveyer, coupled with the irregular shaped bulk material, makes it difficult to utilize a high percentage of the available space in the container; there simply is not enough clearance in the container to permit stacking bulk material beyond a certain height. Also, the size of the bulk material, particularly Heavy Melting Scrap (“HMS”), is often too large to be properly transported using the conveyer belt, requiring the bulk material to be further shredded or otherwise reduced in size before being loaded. Moreover, it is not uncommon to have irregularly shaped pieces of material to impact with the sidewalls of the container while being loaded. Such impacts can severely damage the sidewalls, which are generally very thin. Such impacts are especially common when loading HMS.
Another method to load bulk material into a freight container is to use a skid loader. When using a skid loader, the bulk material is carried into the container and then dumped in place. This method is also less than satisfactory. Errors in operation of the skid loader can lead to physical injuries to workmen, and can also easily damage the sidewalls and ceiling of the container. Also, only small skid loaders can be used because of the relatively small size of the containers in which they are to operate. The use of small skid loaders requires operators to make numerous trips between the bulk material pile and the freight container. Furthermore, because the skid loader operates by lifting its bucket and then dropping its load, it is impossible to load material above a certain height within the container, decreasing the effective utilization of the container.
U.S. Pat. No. 7,172,382 to Frankel (“Frankel”), discloses an additional method and apparatus for loading bulk material into a freight container. Frankel discloses a loading assembly including a support structure, a load bin having a cross section conforming to an open end of a container, and a drive mechanism configured to urge the load bin into and out of the container. When fully inserted, the contents of the load bin are disposed within the container. The loading assembly further includes a barrier configured to keep the load confined within the container while the load bin opens to allow the load to remain within the container upon retraction of the load bin. The barrier projects above the top of the load bin to follow the frame of the support structure, and is not inserted into the container. The device disclosed by Frankel is unsatisfactory, as it is overly complicated and expensive. It has numerous moving parts and drive mechanisms which are susceptible to failure, requiring costly repairs and decreasing loading efficiency.
Thus, better apparatuses and methods for loading bulk material into freight containers are needed.
BRIEF SUMMARY OF THE INVENTION
Accordingly, disclosed are apparatuses and methods for use thereof for loading bulk material into freight containers.
In one embodiment, an apparatus for loading material into a shipping container is disclosed. The apparatus comprises a hopper and a ram. The hopper is sized and shaped to receive the material and be at least partially enclosable by the container to occupy a substantial volume of the container. The hopper comprises a first end and a second, substantially open end positioned opposite the first end. The ram comprises a plate and a driver. The plate has a width less than an internal width of the hopper and a height that does not extend beyond a top of the hopper. The plate is configured to move between the first end and the open end of the hopper. The driver is configured and capable of moving the plate between the first end and the open end to load the material into the shipping container. Optionally, the driver comprises a hydraulic cylinder.
In another embodiment, the apparatus further comprises a stand mounted near the first end of the hopper. The stand is configured to support the hopper above the ground at a height approximately equivalent to the height of the container above the ground. Optionally, the stand remains stationary with respect to the hopper.
In one embodiment, the apparatus further includes collapsible legs configured to support the hopper above the ground at a height approximately equivalent to the height of the container above the ground when the collapsible legs are extended. In one embodiment, the collapsible legs are mounted to the hopper. In another embodiment, the collapsible legs are mounted to the ground. In one embodiment, the collapsible legs are configured to collapse upon impact with the container. Optionally, the apparatus further comprises a hydraulic mechanism attached to the collapsible legs to collapse the legs prior to impacting the container. In another embodiment, the hopper comprises recesses for receiving the collapsible legs, thereby giving the hopper a flat bottom surface when the collapsible legs are collapsed.
A method of loading a shipping container with material is also disclosed. The method comprises: (a) providing a loader comprising a hopper with a first end and a second, substantially open end opposite the first end; (b) loading the material into the hopper; (c) partially enclosing at least a portion of the hopper within the container; and (d) pushing the material towards the open end while moving the container away from the hopper.
Optionally, the loader further comprises a hydraulic cylinder coupled to a plate positioned adjacent the material, and step (d) comprises operating the hydraulic cylinder to push the plate towards the open end. In another embodiment, the loader further comprises a walking floor including a plurality of slats and a drive mechanism supporting the material, and step (d) comprises operating the walking floor to push said material towards said open end.
In an embodiment, the loader comprises support legs and further comprises the step of extending the support legs to support said hopper.
In one embodiment, the container is attached to a flatbed tractor-trailer.
Optionally, step (c) comprises: positioning the container in front of the hopper; moving the container backwards towards the hopper; and enclosing at least a portion of the hopper in the container.
In one embodiment, the material is pushed towards the open end at a predetermined speed and the container is moved away from the hopper at approximately the same speed.
In yet another embodiment, the support legs are collapsed upon impact with the container. In another embodiment, the support legs are collapsed prior to being impacted by the container.
In an additional embodiment, step (d) comprises putting the flatbed tractor-trailer in neutral, thereby causing the material to push the flatbed tractor-trailer forward. In another embodiment, step (d) comprises driving the flatbed tractor-trailer forward.
A hopper for loading material into a shipping container is also disclosed. The hopper comprises: a first end; a second, substantially open end positioned opposite the first end; and a reciprocating conveyor floor system extending from the first end to the second end. The reciprocating conveyor floor comprises a plurality of horizontal slats and a drive mechanism configured to move groups of slats in an alternating manner. The hopper is sized and shaped to be at least partially enclosable by the container to occupy a substantial volume of the container.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention, the objects and advantages thereof, reference is now made to the following descriptions taken in connection with the accompanying drawing in which:
FIG. 1 illustrates a container and a bulk material loader, according to an embodiment of the invention, for use therewith.
FIG. 2 illustrates a side view of the container and the bulk material loader of FIG. 1 .
FIG. 3 illustrates a top view of the container and the bulk material loader of FIG. 1 .
FIG. 4 illustrates top views of a bulk material loader with a reciprocating conveyor floor system, according to an embodiment of the invention, for use therewith.
FIG. 5 illustrates a side view of the container and the bulk material loader when the bulk material loader is inserted into the container, according to an embodiment.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1 , depicted is a bulk material loader 100 , according to an embodiment of the invention, and a container 102 mounted on a flatbed tractor-trailer (only the rear wheels of the flatbed tractor-trailer are shown). In one embodiment, the container 102 is a standard sized container used in the freight industry, and can be a standard 40′, the 40′ high-cube, the standard 20′, or another common sized container. The bulk material loader 100 comprises a hopper 104 . The hopper 104 is suitable to withstand the loading and unloading of bulk material, including HMS, without being damaged. In one embodiment, the hopper 104 is constructed to support and withstand loads in excess of 66,000 pounds, although the loader of the present invention can be constructed to load materials of less than or greater than 60,000 pounds. Referring briefly to FIG. 2 and FIG. 3 , it is apparent that the height and width of the hopper 104 is less than, and preferably slightly less than, the internal height and width of the container 102 . Accordingly, as depicted in FIG. 5 , the hopper 104 can be at least partially enclosed by the container 102 . The exact height and width of the hopper 104 will depend on its specific application, but in one embodiment, the hopper 104 is slightly less than 7′ 8″ tall and slightly less than 7′ 7″ wide, thereby permitting the hopper 104 to fit within most ISO containers. The length of the hopper 104 will also depend on its specific application. In one embodiment, the hopper 104 is at least 40′ long, thereby permitting the hopper 104 to occupy substantially the entire volume of most standard sized containers, as depicted in FIG. 5 . The hopper 104 comprises an open end 116 to permit bulk material to be expelled from the hopper 104 into the container 102 . In some embodiments, and as illustrated in FIG. 1 , the hopper 104 further comprises, for example, a steel frame supporting a steel bottom and two steel sides. In other embodiments, as illustrated in FIG. 4 , the hopper 104 comprises, for example, a steel frame supporting a reciprocating conveyor floor system 400 and two steel sides.
Referring now to FIG. 4 , the reciprocating conveyor floor system 400 , also known as a walking floor, is well known to those skilled in the art, and extends from a back end 114 to the open end 116 of the hopper 104 . The floor system 400 comprises a plurality of horizontal floor slats 402 and at least one drive mechanism (not shown), typically mounted below the slats 402 , configured to move groups of slats in an alternating manner. In one embodiment, every third slat is a member of the same group and is moved in unison, and the floor system 400 operates in a four step process. In Step I, all three groups of floor slats 402 are extended out through the open end 116 of the hopper 104 approximately the same distance. This motion causes ail the bulk material loaded in the hopper 104 to be pushed slightly forward towards the open end 116 of the hopper 104 . The bulk material closest to the open end 116 of the hopper 104 is moved through the open end 116 and out of the hopper 104 while still being supported by the floor system 400 . In Step II, the first group of floor slats 402 of the floor system 400 is retracted into the hopper 104 to its original position. During this retraction, the first group of floor slats 402 changes its position relative to all of the bulk material supported by the floor system 400 . The bulk material external to the hopper 104 remains supported by the second and third group of floor slats 402 . In Step III, the second group of floor slats 402 is retracted into the hopper 104 to its original position. Again, this retraction causes the second group of floor slats 402 to change its position relative to the bulk material supported by the floor system 400 . At this point, the bulk material external to the hopper 104 is supported only by the third group of floor slats 402 . Finally, in Step IV, the third group of floor slats 402 is retracted into the hopper 104 to its original position. This last retraction causes the third group of floor slats 402 to change its position relative to all of the bulk material, and causes the bulk material external to the hopper 104 to no longer be supported by the floor system 400 . As a result, this external bulk material is expelled into the standard container (not shown). Steps I-IV are repeated until all of the bulk material has been unloaded from the hopper 104 .
Referring back to FIG. 1 , the bulk material loader 100 , in some embodiments, further comprises a ram 118 . The ram 118 comprises a plate 106 and a driver 108 . In one embodiment, the plate 106 is sized to fit snuggly to the bottom and sides of the hopper 104 . In a preferred embodiment, the plate 106 is made of a heavy duty steel material. In an embodiment, the plate 106 blocks the back end 114 of the hopper 104 to prevent bulk material from accidentally being expelled from the hopper 104 . The plate 106 is attached to the driver 108 . The driver 108 is a mechanical device configured to move the plate 106 between the back end 114 and the open end 116 of the hopper 104 to load material into the container 102 . In an embodiment of the invention, the driver 108 is capable of moving at least 22,000 pounds. In another embodiment, the driver 108 is capable of moving at least 58,000 pounds.
In an embodiment of the invention, as depicted in FIG. 1 , the driver 108 is a hydraulic cylinder. In this embodiment, the plate 106 is attached to the hydraulic cylinder's adjustable piston rod. Thus, when the piston rod of the driver 108 is extended, the plate 106 is pushed from the back end 114 of the hopper 104 to the front open end 116 of the hopper 104 . The hydraulic cylinder is any standard hydraulic cylinder, well known to those skilled in the art, capable of pushing scrap metal or similar bulk material out of hopper 104 . As is apparent to those skilled in the art, the hydraulic cylinder is part of a hydraulic system (not shown), the main components of which are a hydraulic pump, a hydraulic cylinder, and a series of electrical controls. When the driver 108 is a hydraulic cylinder, the length of the hydraulic cylinder varies based on the length of hopper 104 . In one embodiment, as most clearly depicted in FIG. 2 and FIG. 3 , the hydraulic cylinder is long enough to adjust the position of the plate 106 from the back end 114 of the hopper 104 to the front open end 116 of the hopper 104 .
Those skilled in the art will recognize that the driver 108 need not be a hydraulic cylinder, and can be any mechanical device(s) capable of moving the plate 106 between the back end 114 and the open end 116 of the hopper 104 . Thus, in one embodiment, the driver 108 comprises a chain or belt drive (not shown) connected to the plate 106 . In another embodiment, the driver 108 comprises a rack and pinion setup (not shown), where the pinion is connected to a motor to drive the rack forward and or backward. The pinion is connected to the plate 106 to move the plate 106 between the back end 114 and the open end 116 of the hopper 104 . In yet another embodiment, driver 108 is a screw system (not shown) designed to move the plate 106 between the back end 114 and the open end 116 of the hopper 104 . All of these configurations including their operations are well known to those skilled in the art.
In another embodiment, the bulk material loader 100 further comprises a stand 110 onto which the hopper 104 is mounted. In one embodiment, most clearly depicted in FIG. 2 , the hopper 104 is mounted to the stand 110 such that hopper 104 is off the ground and positioned at approximately the same height as the container 102 . In this way, the hopper 104 can easily be partially enclosed by the container 102 without having to alter the distance between the ground and the container 102 or the hopper 104 . As will be apparent, the exact height of the hopper 104 off the ground will depend on the specific application. In one embodiment, the hopper 104 is mounted to the stand 110 such that the hopper 104 is approximately 5′ off the ground. In another embodiment, the hopper 104 is mounted such that it is between approximately 3′ 2″ and 3′ 4″ off the ground. The stand 110 is made from heavy duty steel and, in some embodiments, is capable of supporting the entire weight of the loaded hopper 104 , thereby preventing the bulk material loader 100 from tipping over or otherwise being damaged. In one embodiment, the stand 110 is counterbalanced with concrete blocks or a similar material (not shown) to enable the stand 110 to support the weight of the hopper 104 . All or part of the driver 108 can also be mounted to the stand 110 as necessary, depending on the specific implementation of the driver 108 . Thus, when the driver 108 is a hydraulic cylinder, as depicted in FIG. 1 , the driver 108 is mounted to the stand 110 .
Referring to FIG. 1 and FIG. 2 , in another embodiment, the bulk material loader 100 also comprises collapsible support legs 112 . These support legs 112 prevent the bulk material loader 100 from tipping over under heavy loads and allow the hopper 104 to be loaded quicker in high volume operations. The support legs 112 collapse towards the stand 110 , thereby enabling portions of the hopper 104 beyond the point of the support legs 112 to occupy space within the container 102 . Once the support legs 112 have collapsed, any necessary support is provided by the container 102 and flatbed. In one embodiment, the support legs 112 are hingedly mounted to the bottom of the hopper 104 . In a more detailed embodiment, the bottom of the hopper 104 has recesses configured to receive the collapsed support legs 112 . In this embodiment, when the support legs 112 collapse they are received in complimentary recesses, giving the hopper 104 a flat bottom and preventing the support legs 112 from protruding beyond the bottom of the hopper 104 when collapsed. Thus, the support legs 112 are protected from damage when collapsed, and weight not supported by the stand 110 is transferred through the entire portion of the hopper 104 inside the container 102 to the container 102 and flatbed. In one embodiment, the bottom of the hopper 104 includes multiple rollers to facilitate the movement of the container 102 relative to the hopper 104 . In another embodiment, the collapsible support legs 112 are hingedly mounted to the ground. In this embodiment, the usable space of the hopper 104 is increased because clearance for the support legs 112 inside the container 102 is no longer required. For example, the legs 112 can be mounted to a foundation provided on the ground with a hydraulic line connected to it.
In accordance with an embodiment of the invention, operation of the bulk material loader 100 proceeds as follows. First, the length of the container 102 must be determined to set the position of the piston rod of the driver 108 and thus the position of the plate 106 in the hopper 104 . For instance, if the container 102 is a standard 20′, then only 20′ of the hopper 104 or less can be used to occupy space within the container 102 . For example, in this case, the piston rod of the hopper 104 must be set so that the plate 106 is 20′ from the front opening of the hopper 104 . If, on the other hand, the container 102 is a standard 40′ and the hopper 104 is 40′ long, then the piston rod must be fully retracted so that the plate 106 is at the back end 114 of the hopper 104 . Once the plate 106 is set in position, and the support legs 112 are extended (if necessary), the bulk material is loaded into the hopper 104 . Any type of material can be loaded, including HMS over 6′ in length. In one embodiment, the bulk material is dumped into the hopper 104 through the open top of the hopper 104 . Once the hopper 104 is loaded, the container 102 , still attached to the flatbed tractor-trailer, is positioned in front of the hopper 104 and is backed up to enclose the hopper 104 within the container 102 . If the support legs 112 are extended, they collapse when impacted by the container 102 . Alternatively, the support legs 112 are set to collapse prior to being impacted by the container 102 . As a result of the flatbed tractor-trailer hacking up, the hopper 104 is at least partially enclosed by the container 102 , one embodiment of which is illustrated in FIG. 5 . At this point, the hydraulic system is activated to push the piston rod of driver 108 forward. The piston rod pushes the plate 106 , which in turn pushes the bulk material out of, the front opening of the hopper 104 and into the container 102 . As bulk material is pushed into container 102 , the flatbed tractor-trailer moves forward so as to fill the container 102 with all of the material in the hopper 104 . In one embodiment, at the same time the hydraulic system is activated, the flatbed tractor-trailer is set to neutral. As a result of the bulk material being pushed into the container 102 , the flatbed tractor-trailer is pushed forward. In another embodiment, when the hydraulic system is activated, the flatbed tractor-trailer is slowly driven forward at approximately the same speed the hydraulic piston is pushing the plate 106 . In this manner, when the hydraulic piston of the driver 108 is fully extended, all of the bulk material that was in the hopper 104 is pushed into the container 102 . Once all of the material is loaded in the container 102 , the flatbed tractor-trailer pulls forward, the container 102 doors are closed, and the flatbed tractor-trailer drives away.
Referring now to FIG. 1 , embodiments of the invention have several advantages over the prior art. For instance, the bottom and side walls of the hopper 104 prevent the container 102 from coming into contact with the bulk material when the bulk material is moving with respect to the container 102 . Thus, at no point can the container 102 suffer damage from the bulk material. Furthermore, the bulk material loader 100 has few moving parts. In one embodiment, only the driver 108 and the plate 106 move, leading to less wear and tear on the loader 100 , and less chance for damage and costly repairs. In another embodiment, the bulk material loader 100 utilizes a readily available reciprocating conveyor floor system (not shown), reducing costs and deployment time. Also, in some embodiments, a flatbed tractor-trailer engine is used in the loading process to reduce the amount of work to be done by the bulk material loader 100 , again reducing costs and the likelihood of failures.
While in accordance with the patent statutes, description of the various embodiments and examples have been provided, the scope of the invention is not to be limited thereto or thereby. Modifications and alterations of the present invention will be apparent to those skilled in the art without departing from the scope and spirit of the present invention.
Therefore, it will be appreciated that the scope of this invention is to be defined by the appended claims, rather than by the specific examples which have been presented by way of example. | Disclosed are apparatuses and methods for use thereof for loading bulk material into freight containers. One apparatus comprises a hopper configured to receive bulk material that is sized and shaped to be at least partially enclosable by a container to occupy a substantial volume of the container and a ram. The ram comprises a plate and a driver configured to move the plate from a back end of the hopper to an open end of the hopper to expel material into a container. Another apparatus comprises a hopper configured to receive bulk, material that is sized and shaped to be at least partially enclosable by a container to occupy a substantial volume of the container and a reciprocating conveyor floor system. Optionally, the apparatuses further include a stand and/or collapsible legs to further support the hopper. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application is based upon and claims the benefit of priority from U.S. patent application Ser. No. 60/760,139, filed Jan. 19, 2006, the entire disclosure of which is incorporated herein by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
[0002] The invention was made with the U.S. Government support under Contract No. BES-0086709 awarded by the National Science Foundation. Thus, the U.S. Government has certain rights in the invention.
FIELD OF THE INVENTION
[0003] The present invention relates generally to apparatus and method for spectrally encoded endoscopy and, more particularly to, e.g., apparatus for obtaining information for a structure using spectrally-encoded endoscopy techniques and method for producing one or more optical arrangements.
BACKGROUND OF THE INVENTION
[0004] Certain medical and technical applications utilize an ability to look inside the patient's body or use a particular device when the available pathways for probe advancement are of very narrow diameter (e.g., small vessels, small ducts, small needles, cracks etc.).
[0005] Conventional miniature endoscopes are generally composed of fiber-optic imaging bundles. These conventional instruments have diameters that range of from approximately 250 μm to 1.0 mm. Since optical fibers have a finite diameter, a limited number of fibers can be incorporated into one imaging bundle, resulting in a limited number of resolvable elements. The resultant image resolution and field of view provided by these imaging devices may be insufficient for obtaining endoscopic images of diagnostic quality in patients. The use of multiple fibers for imaging also increases the rigidity of the endoscopes, likely resulting in a bend radius of approximately 5 cm for the smallest probes in a clinical use. These technical limitations of fiber bundle microendoscopes, including a low number of resolvable points and increased rigidity, have limited the widespread use of miniature endoscopy in medicine.
[0006] U.S. Pat. No. 6,134,003 describes spectrally encoded endoscopy (“SEE”) techniques and arrangements which facilitate the use of a single optical fiber to transmit one-dimensional (e.g., line) image by spectrally encoding one spatial axis. By mechanically scanning this image line in the direction perpendicular thereto, a two dimensional image of the scanned plane can be obtained outside of the probe. This conventional technology provides a possibility for designing the probes that are of slightly bigger diameter than an optical fiber. Probes in approximately 100 μm diameter range may be developed using such SEE technology.
[0007] SEE techniques and systems facilitate a simultaneous detection of most or all points along a one-dimensional line of the image. Encoding the spatial information on the sample can be accomplished by using a broad spectral bandwidth light source as the input to a single optical fiber endoscope.
[0008] FIG. 1 shows one such exemplary SEE system/probe 100 . For example, at a distal end of the exemplary system/probe 100 , light provided by the source can be transmitted via an optical fiber 110 , and collimated by a collimating lens 120 . Further, the source spectrum of the light can be dispersed by a dispersing element 130 (e.g., a diffracting grating), and focused by a lens 140 onto the sample. This optical configuration can provide an illumination of the sample with an array of focused spots 150 (e.g., on a wavelength-encoded axis), where each position (e.g., on the x-axis) can be encoded by a different wavelength ( 1 ). Following the transmission back through the optical fiber, the reflectance as a function of transverse location can be determined by measuring the reflected spectrum. High-speed spectral detection can occur externally to the probe and, as a result, the detection of one line of image data may not necessarily increase the diameter of the exemplary system/probe 100 . The other dimension (e.g., y, slow scan axis) of the image can be obtained by mechanically scanning the optical fiber and distal optics at a slower rate.
[0009] Accordingly, it may be beneficial to address and/or overcome at least some of the deficiencies described herein above.
OBJECTS AND SUMMARY OF THE INVENTION
[0010] One of the objectives of the present invention is to overcome certain deficiencies and shortcomings of the prior art systems and methods (including those described herein above), and provide exemplary embodiments of systems and methods for generating data using one or more endoscopic microscopy techniques and, more particularly to e.g., generating such data using one or more high-resolution endoscopic microscopy techniques.
[0011] For example, certain exemplary embodiments of the present invention can facilitate the use and production of narrow diameter optical fiber probes that use exemplary SEE techniques. Certain procedures and configuration to achieve the preferable optical and mechanical functionality at the distal end of a narrow diameter fiber optical probe for SEE can be provided.
[0012] Different exemplary embodiments can be provided to incorporate the exemplary SEE optical functionality at a tip of the optical fiber in accordance with certain concepts of the present invention. For example, different types of fibers can be used depending on the spectral region and the size/flexibility preferences, e.g., single mode, multimode or double clad fibers can be used.
[0013] In one exemplary embodiment of the SEE system, the same channel can be used for illumination and collecting of the reflected light. Double clad fiber can be employed for improving the collecting efficiency and minimizing the speckle in the exemplary SEE system. For example, a regular telecommunication single mode fiber SMF 28 can be used.
[0014] According to a particular exemplary embodiment of an apparatus for obtaining information for a structure according to the present invention can be provided. For example, the exemplary apparatus can include at least one first optical fiber arrangement which is configured to transceive at least one first electromagnetic radiation, and can include at least one fiber. The exemplary apparatus can also include at least one second focusing arrangement in optical communication with the optical fiber arrangement. The second arrangement can be configured to focus and provide there through the first electromagnetic radiation. Further, the exemplary apparatus can include at least one third dispersive arrangement which is configured to receive a particular radiation which is the first electromagnetic radiation and/or the focused electromagnetic radiation, and forward a dispersed radiation thereof to at least one section of the structure. At least one end of the fiber can be directly connected to the second focusing arrangement and/or the third dispersive arrangement.
[0015] According to still another exemplary embodiment of the present invention, the end and/or the section can be directly connected to the third dispersive arrangement. The second focusing arrangement can include at least one optical element which may be directly connected the end. The second arrangement may include an optical component with a numerical aperture of at most 0.2, and the optical element may be directly connected the optical component. The second arrangement may include an optical component with a numerical aperture of at most 0.2. The end may be directly connected to the optical component.
[0016] In yet another exemplary embodiment of the present invention, the particular radiation can include a plurality of wavelengths and/or a single wavelength that changes over time. The third dispersive arrangement may be configured to spatially separate the particular radiation into a plurality of signals having differing center wavelengths. The first, second and third arrangement can be provided in a monolithic configuration. The third dispersive arrangement may be a fiber grating, a blazed grating, a grism, a dual prism, a binary, prism and/or a holographic lens grating. The second focusing arrangement can include a gradient index lens, a reflective mirror lens grating combination and/or a diffractive lens.
[0017] According to a further exemplary embodiment of the present invention, at least one fourth arrangement can be provided which is configured to control a focal distance of the second focusing arrangement. The third dispersive arrangement may include a balloon. The second focusing arrangement and the third dispersive arrangement can be provided in a single arrangement. The single arrangement may be a holographic arrangement and/or a diffractive arrangement.
[0018] In addition, an exemplary embodiment of a method for producing an optical arrangement can be provided. For example, a first set of optical elements having a first size in a first configuration and a second set of optical elements in cooperation with the second set and having a second size in a second configuration can be provided. The first and second sets can be clamped into a third set of optical elements. The third set can be polished, and a further set of optical elements may be deposited on the polished set.
[0019] According to yet another exemplary embodiment of the present invention, the first set and/or the second set can be at least one set of cylindrical optical elements. At least one of the cylindrical optical elements may be an optical fiber. The third set may be polished at an angle with respect to the extension of at least one of the optical elements. The angle can substantially correspond to a Littrow's angle and/or be substantially greater than 1 degree. The further set may be a grating, and/or can include a diffractive optical element. A layer can be applied between elements of the first set and/or the second set. The layer may be composed of a thin material and/or a soft material.
[0020] Other features and advantages of the present invention will become apparent upon reading the following detailed description of embodiments of the invention, when taken in conjunction with the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Further objects, features and advantages of the present invention will become apparent from the following detailed description taken in conjunction with the accompanying figures showing illustrative embodiments of the present invention, in which:
[0022] FIG. 1 is a schematic diagram of a procedure for implementing one-dimensional space-to-spectrum encoding;
[0023] FIG. 2 is a schematic diagram of an exemplary embodiment of an SEE imaging system/probe;
[0024] FIG. 3 is a schematic diagram of another exemplary embodiment of the SEE imaging system/probe, in which a prism is used as a dispersing element;
[0025] FIG. 4 is a schematic diagram of an additional exemplary embodiment of the SEE imaging system/probe, in which a micro spherical lens is used with the grating following a lens;
[0026] FIG. 5 is a schematic diagram of a further exemplary embodiment of the SEE imaging system/probe, which has a micro spherical lens design with the grating before the lens;
[0027] FIG. 6 is a schematic diagram of an exemplary embodiment of a micro spherical lens configuration with the grating provided before the lens, and in which the lens can be formed by a drop of optical epoxy at a tip of a fiber;
[0028] FIG. 7 is a schematic diagram of an exemplary embodiment of an endoscopic system/probe that can use a holographic optical element (“HOE”) formed in a drop of photosensitized polymer combining the functionality of expansion, focusing and dispersing regions;
[0029] FIG. 8 is a schematic diagram of an exemplary embodiment of the endoscopic system/probe assembly that may be non-monolithic to facilitate zooming and/or refocusing;
[0030] FIG. 9A is a schematic diagram of an exemplary embodiment of the endoscopic system/probe assembly having monolithic distal optics and a grism as a dispersing element in an exemplary configuration for side imaging;
[0031] FIG. 9B is a schematic diagram of another exemplary embodiment of the endoscopic system/probe assembly having monolithic distal optics and a double prism grism as a dispersing element in an exemplary configuration for forward imaging;
[0032] FIG. 10A is a schematic diagram of an exemplary embodiment of a cylindrical grating substrate with a tilted base for a Littrow regime;
[0033] FIG. 10B is a schematic diagram of an exemplary embodiment of a prismatic grating substrate with a tilted base for the Littrow regime;
[0034] FIG. 10C is a schematic diagram of another exemplary embodiment of the cylindrical grating substrate with a mirror tilted base and flatten side for the Littrow regime;
[0035] FIG. 10D is a schematic diagram another exemplary embodiment of the prismatic grating substrate with a mirror tilted base for the Littrow regime;
[0036] FIG. 11A is a schematic diagram of yet another exemplary embodiment of the endoscopic system/probe assembly in an exemplary balloon catheter configuration, in which approximately all of the optical functionality is transferred to the balloon by via HOE that is deposited on the balloon surface;
[0037] FIG. 11B is a schematic diagram of still another exemplary embodiment of the endoscopic system/probe assembly in balloon catheter configuration, in which at least some optical functionality is transferred to the balloon by the use of high refractive index transparent liquid to fill a thin wall balloon to form an inflatable focusing lens;
[0038] FIG. 12 is a schematic diagram of an exemplary embodiment of a catheter system/probe delivery technique using an exemplary guide catheter;
[0039] FIG. 13 is a schematic diagram of another exemplary embodiment of a catheter system/probe delivery procedure using an exemplary biopsy needle;
[0040] FIG. 14 is a flow diagram of a method according to an exemplary embodiment of the present invention for making the exemplary embodiment of the SEE system/probe shown in FIG. 2 ; and
[0041] FIG. 15 is an illustration of procedural steps of an exemplary embodiment of a process for mounting grating substrates which can be facilitated for an exemplary grating fabrication process.
[0042] Throughout the figures, the same reference numerals and characters, unless otherwise stated, are used to denote like features, elements, components or portions of the illustrated embodiments. Moreover, while the subject invention will now be described in detail with reference to the figures, it is done so in connection with the illustrative embodiments. It is intended that changes and modifications can be made to the described embodiments without departing from the true scope and spirit of the subject invention as defined by the appended claims.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0043] Prior to providing a detailed description of the various exemplary embodiments of the methods and systems for endoscopic microscopy according to the present invention, some introductory concepts and terminology are provided below. As used herein, the term “endoscopic probe” can be used to describe one or more portions of an exemplary embodiment of an endoscopic system, which can be inserted into a human or animal body in order to obtain an image of tissue within the body.
[0044] Prior to describing the exemplary embodiments of the systems and/or probes for spectrally encoded endoscopy according to the present invention, certain exemplary concepts and terminology are provided herein. For example, the term “endoscopic probe” may be used to describe a portion of an endoscopic system, which can be inserted into a human body in order to obtain an image of tissue within the human body. The term “monolithic” may be used to describe a structure formed as a single piece, which can have more than one optical function. The term “hybrid” may be used to describe a structure formed as a plurality of pieces, e.g., each piece having one optical function.
[0045] The exemplary embodiments of the system, apparatus, probe and method described herein can apply to any wavelength of light or electromagnetic radiation, including but not limited to visible light and near infrared light.
[0046] FIG. 2 shows an exemplary embodiment of a SEE imaging system/probe 200 (e.g., endoscopic probe having a single mode fiber that deliver light from a light source to the tip of the fiber) which can include an optical fiber 210 , an expansion region 220 , a focusing region 230 , an angled region 240 and a dispersing element 250 (e.g., grating). The exemplary system/probe 200 can generate a spectrally encoded imaging signal, e.g., a line 260 on the imaged surface with the longer wavelengths 280 deviated further from the probe axis than the shorter wavelengths 270 .
[0047] The optical fiber 210 can be a single-mode fiber and/or a multi-mode fiber (e.g., preferably single mode for preserving the phase relation of the source light and the light remitted by the sample). By facilitation a light delivery through the optical fiber 210 , SEE capabilities can be provided in a catheter or endoscope. Thus, a high-resolution microscopy of surfaces of the body accessible by endoscope can be facilitated by the exemplary embodiment of the system/probe 200 .
[0048] A multiple of (e.g., four) distinct regions with specific optical properties can be used to determine the system/probe functionality.
[0049] For example, the expansion region can be used to facilitate the beam that is confined in the fiber core to expand and fill an aperture. The expansion region can be composed of optical glass (e.g., a piece of coreless fiber spliced to the main fiber and then cleaved to a predetermined length), optical epoxy, air, or transparent fluid. Index matching with the fiber core may be desirable for reducing the back reflection from the interface between the fiber and the expansion region. Other techniques and/or arrangements for reducing the back reflection, e.g., anti-reflection coating or angle cleaving, can be employed in case of air or other non-matching media used as an expansion region.
[0050] In the focusing region, the diverging beam can be transformed to a converging one. For example, a gradient index (“GRIN”) lens or spherical micro lens can be used as shall be described in more detail below with reference to other exemplary embodiments. For example, the GRIN lens can be made by splicing a piece of GRIN fiber and cleaving it to a predetermined length. The spherical lens can be formed on the coreless fiber tip by melting it, by polishing, or by applying a small measured amount of optical epoxy.
[0051] The angled region can be used to support the dispersing element and/or provide an incidence tilt for the output direction and/or the desired regime (Litrow) in certain cases (e.g., a diffraction grating). As with the expansion region, different media can be used, and different techniques and/or arrangements for obtaining the desired tilt can be employed. For example, some of such exemplary techniques can include angle cleaving, polishing, molding of the optical epoxy etc.
[0052] The dispersing element can tilt different parts of the incident spectrum at different angles, thus producing the desired spatial spread of the incident light. It can be a prism made of high dispersion material or a high efficiency diffracting grating. It is possible to also produce a grating at the fiber tip. For example, transmitting or reflecting gratings can be used in different regimes depending on the application.
[0053] Other numerous combinations and permutations of the above-mentioned regions can provide a functional system/probe, certain exemplary embodiments of which shall be described in further detail below. For example, two general types of dispersing elements can be used: prism or diffracting grating. The holographic optical element that combines the dispersing power of the grating and the focusing power of a lens can also be used as shown in FIG. 7 .
[0054] Prism made of dispersing material can be used when the light source has a very broad spectrum, e.g., a femto-second laser source with microstructured fiber for super-continuum generation. In such exemplary source, the spectrum can span in visible and near infrared.
[0055] FIG. 3 shows another exemplary embodiment of the SEE system/probe 300 which can include a single mode optical fiber 310 spliced to a coreless fiber 320 (e.g., the expansion region). Further, a short piece of gradient refracting index (GRIN) fiber 330 can be spliced to the coreless fiber (e.g., the focusing region). In addition, another short piece of coreless fiber 340 can be spliced to the focusing region 330 . The output surface 350 may be angle polished/cleaved, thus forming a refracting boundary between the fiber 340 and the external medium 355 (e.g., air, water or other liquid). In FIG. 3 , an exemplary use of the prism 340 is illustrated as a dispersive element. With an anti-reflecting coating on the output surface 350 , this exemplary configuration can provide a high transmission efficiency. It may be desirable for the angled region to be made of a highly dispersive material. In the case of a normal dispersion, longer wavelength parts of the original spectrum 370 may deviate less than the shorter wavelengths 380 , thus forming the imaging line 360 .
[0056] Diffracting gratings can be preferable in the case of narrow band source because of the higher dispersing power that can be achieved with such gratings. For example, the transmission and reflection diffracting gratings can be used. FIG. 5 shows a schematic diagram of a further exemplary embodiment of the SEE imaging system/probe 500 , which has a micro spherical lens 530 with a grating 550 provided before the lens 530 use of the reflection diffracting grating. In other exemplary configuration, the use of reflection diffracting grating utilizes a housing that can enlarge the system/probe. The additional details of the exemplary embodiment of the SEE system/probe 500 shall be described in further detail below.
[0057] The selected dispersing element can be a transmission diffracting grating. It is also possible to use other grating, e.g., a volume holographic grating or a surface phase grating. The volume holographic gratings can exhibit a higher efficiency, but are less common, and some of the materials used therefore generally require sealing from the humidity, as well as more expensive and difficult to replicate. The surface phase gratings may be less efficient, but are easy to replicate and mass-produce when a master grating is made. For both of these exemplary elements, the grating can be a thin film (˜5-10 μm) that is applied to the angled region.
[0058] FIG. 4 shows another exemplary embodiment of the SEE system/probe 400 which can include a single mode optical fiber 410 spliced to a coreless fiber 420 . In this exemplary embodiment, the tip of the expansion region 420 can be melted to form a small spherical surface 425 , and then a low refractive index epoxy 430 may be used to attach the grating 440 at an angle to the system/probe 400 . In this exemplary system/probe 400 , the focusing region can be the surface that separates the expansion region and the angled region. The longer wavelengths 460 of the original spectrum may deviate more than the shorter wavelengths 470 , thus possibly forming the imaging line 450 .
[0059] FIG. 5 shows the exemplary SEE probe 500 described above, which can include a single mode optical fiber 510 spliced to a coreless fiber 520 . The tip of the expansion region 520 can be melted to form a ball 530 . The ball may be polished at an angle (Littrow) and on the flat surface 540 that can result from this exemplary procedure, a reflecting grating 550 may be deposited. The light beam can expand in the expansion section after exiting an end 510 of the core of the optical fiber 510 , and may then be dispersed by the grating 550 . Different monochromatic beams that can result may then be focused by the near spherical surface of the glass ball to form the imaging line 560 . The dispersing element may be provided before the focusing element. The longer wavelengths 580 of the original spectrum may deviate more than the shorter wavelengths 570 .
[0060] FIG. 6 shows another exemplary embodiment of the SEE system/probe 600 which may include a single mode optical fiber 610 spliced to a short piece of coreless fiber 620 that may be angle cleaved or polished at an angle (which can be the Littrow angle for the grating 630 ) and the grating 630 may be deposited on the tip of the expansion region 620 . A drop of an optical epoxy 640 can be cured at the tip of the fiber 610 to protect the transmission grating 630 and form the focusing surface 650 . The dispersing element 630 can be provided before the focusing element 650 , and the expansion region 620 and the angled region 620 may coincide. The longer wavelengths 670 of the original spectrum may deviate more than the shorter wavelengths 680 to form the imaging line 660 .
[0061] FIG. 7 shows yet another exemplary embodiment of the SEE system/probe 700 , which can include a single mode optical fiber 710 . A holographic optical element (“HOE”) 730 written in a drop of photosensitive polymer 720 can incorporate the optical functionality of the expansion, focusing and dispersing elements. The longer wavelengths 750 of the original spectrum can deviate more than the shorter wavelengths 760 to form the imaging line 740 .
[0062] FIG. 8 shows still another exemplary embodiment of the SEE system/probe 800 which can include a static monolithic core 810 and a spinning flexible thin wall Teflon tubing 820 with the angled region 850 attached to its end. An optical fiber 830 , an expansion region 835 , and a focusing region 840 may be attached/glued/spliced together to form the core 810 . A dispersing element/grating 857 can be deposited on the tilted output surface of the angled region 850 . The glass-to-air interfaces of the focusing region 840 845 and the angled region 850 853 may be anti-reflection coated. Changing the gap between such elements by advancing the core 810 can effectively change the distance 880 of the imaging line 860 to the output surface of the system/probe 800 (e.g., the grating 875 ).
[0063] Exemplary non-monolithic configurations similar to those shown in the exemplary embodiment of FIG. 8 can allow for additional functionality such as zooming and/or focusing to be provided in the distal probe end. Multi-lens configurations may also be implemented.
[0064] The use of a prism-grating combination (grism) may facilitate a control of the angle of incidence and the probe output direction. Exemplary arrangement which implements such configurations are shown in FIG. 9A and FIG. 9B . In particular, FIG. 9A shows a further exemplary embodiment of the SEE imaging system/probe 900 which can include a static sheath 905 with a transparent window 908 and a monolithic optical core 910 that can be scanned. The core can include an optical fiber 915 , an expansion region 917 , a focusing element (e.g., a GRIN lens) 920 , and a prism 925 with the grating 930 deposited on its output surface. The optical elements may be maintained together with a micro mechanical housing 940 . This exemplary configuration may represent a side looking imaging system/probe.
[0065] FIG. 9B shows still another exemplary embodiment of the SEE imaging system/probe 950 which can include a static sheath 955 with a transparent window 958 and a monolithic optical core 960 that can be scanned. The core can include an optical fiber 965 , an expansion region 967 , and a focusing element (GRIN lens) 970 . A grating 980 may be sandwiched between prisms 975 and 977 . The optical elements may be maintained together with a micro mechanical housing 990 . This exemplary configuration can represent a forward-looking imaging system/probe.
[0066] It may be beneficial for this exemplary application to utilize a grating in Littrow regime when the angle of incidence is equal to the angle of diffraction (e.g., for the central wavelength). In this exemplary configuration, the shape of the beam may not change after the grating, and thus provide an effective regime. FIGS. 10A-10C illustrate exemplary embodiments of the substrate that can provide a Littrow regime for the grating.
[0067] For example, FIG. 10A shows an exemplary embodiment of a diffracting grating substrate 1000 which can include a cylindrical body 1005 with one side 1020 polished at the Littrow's angle 1015 . FIG. 10B shows another exemplary embodiment of the diffracting grating substrate 1025 which includes a prismatic body 1030 with one side 1045 polished at the Littrow's angle 1040 . FIG. 10C shows still another exemplary embodiment of the diffracting grating substrate 1050 which can include a cylindrical body 1055 with one side 1057 polished at the complimentary to Littrow's angle 1058 and a mirror 1087 deposited. Another flat surface 1065 may be polished parallel to the cylinder axis where the grating is to be deposited. FIG. 10D shows yet another exemplary embodiment of the diffracting grating substrate 1075 which can include a prismatic body 1080 with one side 1087 polished at the complimentary to Littrow's angle 1085 and a mirror 1087 deposited. The grating is intended to be deposited on the side 1095 . It should be understood that the illustrated sizes are merely exemplary, and other sizes are possible and are within the scope of the present invention.
[0068] In certain exemplary applications, the system/probe can be small enough to be introduced through a small opening, and big enough to be able to image at big distances in a cavity. These conflicting preferences can be met by using an inflating balloon with added optical functionality. Two such exemplary configurations are shown in FIGS. 11A and 11B .
[0069] In particular, FIG. 11A shows another exemplary embodiment of the SEE system/probe 1100 which can include a single mode optical fiber 1110 . A holographic optical element (“HOE”) 1125 written on the surface of the inflating balloon 1120 can incorporate the optical functionality of the focusing and dispersing elements. The dispersed light may be focused into the imaging line 1130 . When the exemplary system/probe 1100 is spun, the image of the area 1135 may be obtained. This exemplary configuration may be further defined by the material availability for infrared applications and the possible difficulties associated with the holographic process.
[0070] FIG. 11B shows still another exemplary embodiment of the SEE system/probe 1150 which can include a single mode optical fiber 1160 . A holographic optical element (“HOE”) 1165 written in a drop of photosensitive polymer 1067 deposited on the tip of the fiber 1060 can incorporate the optical functionality of the expansion, and dispersing elements. Further, the balloon catheter 1170 may be filled with a high refractive index biocompatible liquid, thus forming a near spherical refracting focusing surface 1175 . This exemplary configuration may be further defined by the material availability for infrared applications and the possible difficulties associated with the holographic process.
[0071] One exemplary advantage of the various exemplary embodiments of the present invention may be the relative simple configurations and designs of the exemplary embodiments of the systems/probes. According to one exemplary embodiment, e.g., the system/probe can include an optical fiber with a modified tip. (See FIGS. 2-7 ). For example, the system/probe can illuminate a line at the object and acquire one line of image at a time. In order to acquire an image with this exemplary system/probe, it may be preferable that the imaging line is scanned in transverse direction across the object. This can be a repetitive or a single scan. In such cases, an image or the surface that the line scans can be acquired and displayed. The information obtained from the back-scattered light can be interpreted in various manners to represent different tissue types, different states of the same tissue, various types of dysphasia, tissue damage etc. as well as motion of body liquids and cells. Certain exemplary arrangements which can be used for placing the probe and scanning the tissue may be as follows.
Catheter Exemplary Embodiments
[0072] Where catheters are used in medicine, a very thin wall sealed PTFE tube can be used as a protective transparent sheath for the probe that can be delivered through the lumen of a guide catheter to the area of interest (as shown in FIG. 12 ). When in place, the fiber inside the thin tube can be scanned by rotating or by pulling in order to obtain an image. A short distal part of the catheter can be of a small diameter. The proximal end can be of a bigger diameter with added additional springs/shafts to protect the fiber and convey the motion.
[0073] For example, FIG. 12 shows an exemplary embodiment of a catheter of the SEE system/probe 1200 which can include an optical core 1230 . The exemplary system/probe 1200 can be protected by a transparent sheath 1220 that can allow the transmission of the imaging light 1240 into the region of interest. The imaging catheter 1220 can be placed trough a guide catheter 1210 .
Needle Exemplary Embodiments
[0074] For needle biopsies that are traditionally performed under CT, MRI, or ultrasound guidance, the fiber optic probe may be inserted into the biopsy needle (as shown in FIG. 13 ). In this exemplary configuration, the fiber optic probe may be embedded within the needle biopsy device or inserted through the lumen of the needle. The image can be acquired during the insertion of the needle or by rotating of the probe inside the needle and, e.g., only looking at a limited angle
[0075] FIG. 13 shows another exemplary embodiment of a catheter of the SEE system/probe 1300 which can include an optical core 1330 . The exemplary system/probe 1300 can be delivered to the region being imaged through the lumen of a biopsy needle 1320 that may be delivered through an endoscope or guide catheter 1310 .
Intraoperative Exemplary Embodiments
[0076] For example, the exemplary system/probe may be incorporated into an electrocautery device, scalpel, or be an independent hand-held device.
Exemplary Optical Parameters
[0077] One exemplary parameter for comparing different miniature endoscope technologies may be the number of resolvable points. This exemplary parameter can be the limiting factor that may render a technology more or less useful for the particular application. The total number of resolvable points provided by the exemplary embodiments of the SEE system/probe (n) for the first diffraction order can be defined by:
n = ( Δ λ d λ 0 Λ cos ( θ i ) ) 2
[0078] Exemplary determinations can indicate that for a source with a center wavelength, λ 0 , source bandwidth, Δλ, of 250 nm, a grating input angle, θ i , of 49° and a grating groove density, Λ, of 1800 lines per mm, a 250 μm diameter SEE probe may facilitate imaging with, e.g., 40,000 resolvable points. In comparison, a commercially available 300 μm diameter fiber-optic image bundle (Holl Meditronics, 30-0084-00) contains only 1,600 resolvable points.
[0079] FIG. 14 shows a flow diagram of a method according to an exemplary embodiment of the present invention for making the exemplary embodiment of the SEE system/probe shown in FIG. 2 . In particular, the end of SMF-28 optical fiber 210 or any other optical fiber can be stripped (step 1410 ). In step 1420 , the spacer can be polished to a predetermined length. The GRIN lens can be polished to a predetermined length in step 1430 . Further, in step 1440 , the grating 250 can be polished to a predetermined length and angle.
[0080] The results of step 1410 are provided to step 1450 , in which the end of the optical fiber is cleaved. The results of steps 1420 and 1430 are provided to step 1460 , in which the spacer and GRIN lens are glued together. The results of step 1440 are provided to step 1470 , in which the grating 250 is deposited on the grating substrate. The results of steps 1450 and 1460 are provided to step 1475 , in which the spacer-GRIN lens assembly is glued to the optical fiber using an optical epoxy and the spacing is varied to achieve the desired focal properties. The results of steps 1475 and 1470 are provided to step 1485 in which the grating 250 bearing the grating substrate is glued to the GRIN lens. In step 1480 , flexible, optically clear, bio- and device-compatible sheath can be provided for housing the imaging core. The results of steps 1480 and 1485 are forwarded to step 1490 , in which the exemplary system/probe is assembled, e.g., by inserting the core into the sheath and sealing and sterilizing the resultant assembly.
[0081] FIG. 15 shows an illustration of procedural steps of an exemplary embodiment of a process for mounting grating substrates which can be facilitated for an exemplary grating fabrication process. It should be understood that dimensions provided in FIG. 15 are exemplary, and numerous other dimensions can be utilized in accordance with the exemplary embodiments of the present invention. For example, several glass rods with different diameters 1500 , 1510 can be stacked and mounted together inside a particular mount 1520 into a particular location 1525 . The rods can be separated by a thin lead foil 1530 (e.g., 127 mm thick). The rod stack can then be polished at an angle while inside the mount 1520 . After polishing, the polished face can be cleaned, and a grating 1540 may be fabricated, e.g., without disassembling the pieces. When grating fabrication is completed, the pieces can be disassembled. The individual pieces may then be polished from the other side 1550 . The completed grating 1560 can then be assembled into the fiber or lens.
[0082] The foregoing merely illustrates the principles of the invention. Various modifications and alterations to the described embodiments will be apparent to those skilled in the art in view of the teachings herein. Indeed, the arrangements, systems and methods according to the exemplary embodiments of the present invention can be used with and/or implement any OCT system, OFDI system, SD-OCT system or other imaging systems, and for example with those described in International Patent Application PCT/US2004/029148, filed Sep. 8, 2004, U.S. patent application Ser. No. 11/266,779, filed Nov. 2, 2005, and U.S. patent application Ser. No. 10/501,276, filed Jul. 9, 2004, the disclosures of which are incorporated by reference herein in their entireties. It will thus be appreciated that those skilled in the art will be able to devise numerous systems, arrangements and methods which, although not explicitly shown or described herein, embody the principles of the invention and are thus within the spirit and scope of the present invention. In addition, to the extent that the prior art knowledge has not been explicitly incorporated by reference herein above, it is explicitly being incorporated herein in its entirety. All publications referenced herein above are incorporated herein by reference in their entireties. | Exemplary apparatus for obtaining information for a structure can be provided. For example, the exemplary apparatus can include at least one first optical fiber arrangement which is configured to transceive at least one first electromagnetic radiation, and can include at least one fiber. The exemplary apparatus can also include at least one second focusing arrangement in optical communication with the optical fiber arrangement. The second arrangement can be configured to focus and provide there through the first electromagnetic radiation. Further, the exemplary apparatus can include at least one third dispersive arrangement which is configured to receive a particular radiation which is the first electromagnetic radiation and/or the focused electromagnetic radiation, and forward a dispersed radiation thereof to at least one section of the structure. At least one end of the fiber can be directly connected to the second focusing arrangement and/or the third dispersive arrangement. In addition, an exemplary embodiment of a method for producing an optical arrangement can be provided. For example, a first set of optical elements having a first size in a first configuration and a second set of optical elements in cooperation with the second set and having a second size in a second configuration can be provided. The first and second sets can be clamped into a third set of optical elements. The third set can be polished, and a further set of optical elements may be deposited on the polished set. | 6 |
REFERENCE TO RELATED APPLICATION
The subject matter of this application is related to the subject matter of U.S. patent application Ser. No. 319,120, filed on Mar. 3, 1989, entitled "Full Felled Seam Fold Assembly."
BACKGROUND OF THE INVENTION
This invention relates to systems for automatic or computer-controlled manipulation of sheet material during processing, e.g., fabric or other limp material to be assembled at a sewing station.
During the construction of a useful item from raw stock of flat goods (e.g., cloth, paper, plastic, and film), it is often necessary to precisely position and guide the flat goods through a work station. Typical work stations perform assembly operations such as joining, cutting or folding. For example, such work stations can be equipped with sewing machines for joining multiple layers of limp fabric, such as may be from separate limp material segments, or from several regions of the same (folded) limp material segment.
Conventionally, the positioning and guiding of the fabric-to-be-joined is accomplished by skilled human operators. The operators manually feed or advance the fabric-to-be-joined through the stitch forming mechanism of the sewing machine along predetermined seam trajectories on the fabric. The resultant seams can be straight or curved, or a combination of both as is often required in the assembly of fabric panels to form articles of clothing, for example. Typically, the fabric-to-be-joined must be precisely positioned and accurately directed to the sewing head to achieve the desired seam. The human operator must therefore function not only as a "manipulator" of the fabric but also as a real-time "sensing and feedback medium", making small adjustments, e.g., in orientation, fit-up and seam trajectory, to obtain quality finished goods. The adjustments are required, for example, due to variations in seam type, geometry, location and fit-up.
There are many forms of seams that are conventionally formed, such as superimposed seams, lapped seams, bound seams, and edge finishing seams. Such seams are described generally in "The Technology of Thread and Seams", J&P Coats Limited, Glasgow, Scotland (undated), pages 74-79.
One form of seam which is required in the fabrication of certain articles is the so-called full felled or double lapped seam. The full felled seam is typically used to join one lateral edge of each of two limp material segments. In that seam, the edges to be joined are folded over in an interlocking relationship (where their cross-sections form interleaved opposed V's or C's) and then one or two rows of stitches are established along the principal axis of the seam through all four layers of the interlocked segments.
In the prior art, to assist in the formation of such a seam, an operator manually presents and feeds two limp material segments to be joined to a fold assembly coupled to a sewing machine. The fold assembly, for example, a Simanco USA model 230056. is adapted to receive the presented segments and to guide the edges so that at the output end of the fold assembly, the two segments emerge with their lateral edges interlocked and ready for joining. The fold assembly is positioned so that the emerging segments are driven by the feed dogs of the sewing machine to the needle and bobbin assembly of the sewing head of the machine.
One drawback of this technique is that it is labor intensive; that is, a large portion of the cost for manufacture is attributable to manual labor. One of the further problems of the prior art seam forming techniques lies with the conventional fold assembly. With such an assemblY, the formation of straight seams is fairly effective, although considerable manual assistance is required. However, the formation of a curved felled seam is extremely difficult, due to bunching of the limp material segments as they are fed to and drawn through the fold assembly.
To reduce labor cost in the clothing assembly industry, automated or computer-controlled manufacturing techniques have been developed for many of the desired assembly operations. However, there have not been any effective techniques developed for the automated formation of high quality full felled seams. Moreover, even the manual assisted techniques have limited effectiveness due to the required degree of human intervention and are limited in their ability to accommodate curved seams.
Accordingly, it is an object of the invention to provide an improved method and apparatus for positioning and guiding sheet material, e.g., fabric or other limp material to be processed, in the formation of seams.
It is another object of the present invention to provide an improved flat-material manipulation device suitable for automatic or computer-controlled seam forming operations, which is of simple, rugged, versatile, and economical design.
SUMMARY OF THE INVENTION
These and other objects of the invention are accomplished by an improved apparatus for controlling the position of sheet material, e.g., fabric or other flat goods, slidingly supported on a work surface with a relatively low coefficient of friction.
The present invention is a seam forming apparatus for forming a seam at one lateral edge of one limp material segment (e.g. an edge finishing seam, such as a hem), or at one lateral edge of each of two limp material segments.
The apparatus includes a fold assembly extending along a reference axis from an input end to an output end. The fold assembly establishes a first segment guide channel adapted to receive a first of the limp material segments. That first segment guide channel extends from the input end to the output end, and is open at the input end and at one lateral side.
In some forms of the invention adapted for joining two limp material segments, the fold assembly also establishes a second segment guide channel adapted to receive the second of the limp material segments. That second segment guide channel also extends from the input end to the output end, and is open at the input end and at one lateral side.
The first and second segment guide channels each extend about an associated channel axis extending substantially parallel to the reference axis near the output end of the fold assembly.
For a full felled seam, the two segment guide channels of the fold assembly have substantially V- (or C-) shaped cross-sections, and the first and second channels are oppositely directed and interleaved near the output end. As used herein, the terms "V-" and "C-" are used interchangeably to define a shape which curves about a central point, either in a continuous or piecewise continuous manner.
In one form, the invention further includes two feed plane support members. That first feed plane support member has a segment support surface extending substantially to the lower surface of the portion of the first segment guide channel above its associated channel axis at the input end of the fold assembly. The second feed plane support member has a material support surface extending substantially to the lower surface of the portion of the second segment guide channel at the input end of the fold assembly.
A position controller controls the position of the lateral edges of the segments in the channels to be at associated predetermined positions measured with respect to the reference axis at a point along that axis between the input and output ends of the fold assembly. Generally, the controlled edges are laterally spaced apart from the reference axis by an associated predetermined distance near the input end of the fold assembly. The segment edge positions are controlled bidirectionally, and pursuant to a closed loop control system.
In various forms of the invention, the position controller includes segment edge sensors between the input end and output end of the fold assembly. Those edge sensors are adapted to generate position signals representative of the positions with respect to the reference axis of the lateral edges of the limp material segments in their respective channels. Segment drivers are responsive to the position signals for controlling the lateral edges of the segments to be at their associated predetermined positions.
Preferably, the edge sensors are positioned between the segment drivers and the output end of the fold assembly, although in some forms, this configuration may be reversed.
The segment drivers each include a rotatable drive wheel adapted for rotation about an axis substantially parallel to the reference axis. The wheels have their respective lateral surfaces opposite to a platen substantially coincident with a surface of a respective one of the segment guide channels near the input end of the fold assembly.
Preferably, at least one of the platens and the drive wheel surface opposite thereto is positioned within the respective one of the segment guide channels.
The preferred form of the invention is further adapted to selectively bias the outer surfaces of the drive wheels toward their respective platens. By differentially biasing the drive wheels toward their respective platens, differing drags may be established in the two segments, so that a desired relative stretching may be achieved. The lateral surfaces of the drive wheels may selectively be positioned away from their respective platens to permit easy loading of segments to the fold assembly. With the wheels biased toward their respective platens, drive motors coupled to the wheels control the rotational motion of the wheels, together or independently, to establish control of the limp material segment positions within the fold assembly.
The above-described seam forming apparatus may be integrated with the sewing head and feed dog assembly of a sewing machine to form an automated full felled seam forming system. With this configuration, two segments-to-be-joined may be readily loaded in separate (and overlapping) feed planes to the fold assembly. Then, the sewing head may be actuated so that the feed dog assembly draws the two segments through the fold assembly to the needles of the sewing head. As the segments are drawn through the fold assembly, the position of the lateral edges are dynamicallY controlled to establish a high quality seam.
BRIEF DESCRIPTION OF THE DRAWINGS
For a fuller understanding of the features, advantages, and objects of the invention, reference should be made to the following detailed description and the accompanying drawings, in which:
FIG. 1 is a perspective view of an apparatus for forming a full felled seam in accordance with the present invention;
FIG. 2A is a top view of the fold assembly of the system of FIG. 1;
FIG. 2B is a side elevation view from the input end of the fold assembly of FIG. 1;
FIG. 3A is an exploded view of the light source of the optical detector of the system of FIG. 1;
FIG. 3B is a sectional view of the reflector assembly of FIG. 3A;
FIG. 4 is a perspective view of the fold assembly and segment position controller of the system of FIG. 1;
FIG. 5 shows an embodiment of the invention adapted for a feed-off-the-arm sewing machine;
FIG. 6A shows a plan view of the fold assembly Of the System of FIG. 5;
FIG. 6B shows an exploded perspective view of the fold assembly and sensor assembly of the system of FIG. 5;
FIG. 6C shows a sectional view along lines 6C--6C of the sensor assembly of the system of FIG. 6A;
FIG. 7A shows a front plan view of an alternative drive wheel biasing assembly;
FIG. 7B shows a sectional view along lines 7B--7B of the drive wheel biasing assembly of FIG. 7A;
FIG. 7C shows a rear plan view of the drive wheel biasing assembly of FIG. 7A;
FIG. 8A is a top Plan view of an alternative fold assembly for use in the system of FIG. 1;
FIG. 8B is a perspective view of the fold assembly of FIG. 8A;
FIG. 8C is a side elevation view from the output end of the fold assembly of FIG. 8A;
FIG. 9A shows a representation of the cross-sections of limp material segments in the fold assembly of FIGS. 8A, 8B and 8C along lines A--A through F--F;
FIG. 9B shows a representation of the cross-sections of limp material segments in the fold assembly of FIGS. 6A, 6B and 6C along lines A--A through F--F; and
FIG. 10 shows two curved edge limp material segments as positioned in the fold assembly of FIGS. 8A, 8B and 8C.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A seam forming system 10 embodying the invention is shown in FIG. 1. System 10 includes a conventional dual needle sewing head 12 of a flat bed sewing machine. Sewing head 12 is positioned over a work support surface 14 which overlies a conventional dual bobbin assembly (not shown). A pair of conventionally operative feed dog assemblies are positioned with their drive elements 20 and 22 (not shown) extending through the top of work surface 14. The presser foot 13 of head 12 biases the segments against the feed dogs 20 and 22 so that the feed dog assemblies selectively drive a limp material workpiece along a reference axis 26 toward the needles of the sewing head 12.
The system 10 further includes a fold assembly 30 positioned on the work surface 14. The fold assembly 30 defines two limp material segment guide channels 34 and 36 extending laterally into the fold assembly 30, and includes an optical position detection system 37, described in detail below in conjunction with FIG. 4. The workpiece support surface 14 provides a limp material segment support surface leading to the channel 34 and a support element 38 provides a limp material segment support surface leading to channel 36. The channels 34 and 36 are open at the input end of fold assembly 30 and along one lateral side, permitting positioning therein of the lead edges of limp material segments on surfaces 14 and 38.
A first segment drive wheel 40 is positioned with its central axis substantially parallel to axis 26 and its lateral surface adjacent to an effective platen established by the support surface 14. A second segment drive wheel 42 is positioned with its central axis substantially parallel to axis 26 and with its lateral surface adjacent to a platen 44 (shown with broken lines) which overlies the extended plane of support surface 38. The wheels 40 and 42 include axially directed ridges on their lateral surfaces.
The drive wheels 40 and 42 are coupled by respective ones of flexible drive shafts 50, 52 and belts 54, 56 to a respective one of stepper motors 60 and 62.
The drive wheels 40 and 42 are generally biased away from each other, i.e. so that wheel 40 is biased toward surface 14 and wheel 42 is biased toward surface 38. A drive wheel biasing assembly 66, including an associated actuator (not shown), is coupled to the shafts 50 and 52. That assembly 66 is selectively operative to establish the above-noted bias to wheels 40 and 42, or to remove that bias and withdraw wheel 40 from surface 14 and wheel 42 from platen 44. When the wheels 40 and 42 are biased toward surfaces 14 and 38, respectively, limp material segments in the guide channels may be controlled by movement of the wheels. When the wheels 40 and 42 are displaced from the surfaces, segments may be easily loaded or removed from the channels.
In the embodiment of FIG. 1, a linear actuator is used to selectively drive a wedge-shaped element, or cam 68, in the direction of axis 26 to either push apart (in the forward position, as shown in FIG. 1) the shafts 50 and 52, or permit a biasing spring, not shown, to push the wheels together (i.e. away from their respective platens).
A controller 100 is selectively operable to control the operation of the sewing head 12 and its associated feed dog assembly, the optical detection system 37 and the position and rotarY motion of the drive wheels 40 and 42.
In the system 10 of FIG. 1, the fold assembly 30 is similar to a Simanco USA model 230056 folder, which has been modified to include an optical position detection system 37. Fold assembly 30, shown in FIGS. 2A and 2B extends from an input end 30a to an output end 30b along a principal axis 30A. Assembly 30 defines two segment guide channels (having cross-sections indicated bY the broken lines in FIG. 2B) which extend laterally into assembly 30 and curl around the principal axis 30A of assembly 30. Axis 30A effectively provides a reference (or channel) axis about which the cross-section of the channels extend. While offset somewhat from axis 26, axis 30A is "substantially" parallel to axis 26 near the output end of assembly 30.
The assembly 30 includes the optical source and reflector portions of the optical detection system 37. As shown in FIG. 3A, these portions include a light emitting diode (LED) 70 and a dual beam forming reflector assembly 72. The assembly 72, shown in assembled form in FIG. 3B, includes a housing 74, a reflector 76 and a collimator 78. With this configuration, light from LED 70 is split by reflector 76 to form two laterally (with respect to axis 30A) directed beams. As shown in FIG. 4, the beams from reflector 76 are directed across the respective segment guide channels of assembly 30 along propagation paths 79a and 79b to be incident upon the input ends of respective pairs of optical fibers 80 and 82 leading to corresponding pairs of optical detectors 84 and 86 (illustrated in block diagram form in FIG. 4). The optical fiber pairs 80 and 82 are mounted in a housing (not shown) affixed to assembly 30. The optical detectors are operative in conjunction with the controller 100 to identify when a limp material segment in one of the channels 34, 36 blocks the beam from LED 70 from none, one or both of the input ends of the optical fiber pairs.
In operation of the system of FIG. 1, the actuator for assembly 66 is initially positioned so that the wheels 40 and 42 are drawn back from the respective surfaces of surface 14 and platen 44. Then a first limp material segment 101 is positioned between wheels 40 and surface 14 and a second limp material segment 102 is positioned between wheel 42 and platen 44. The two segments are then pushed through the fold assembly 30 to overlie the feed dogs 20 and 22. Then the actuator of assembly 66 is positioned to bias wheels 40 and 42 against surface 14 and platen 44 respectively to engage the respective limp material segments 101 and 102.
Then the feed dogs 20 and 22 and sewing head 12 are actuated to draw the limp material segments 101 and 102 through the fold assembly 30. As the segments are drawn through the assembly 30, the controller determines the position of the lateral edge of those segments bY monitoring the optical detectors 84 and 86. Under closed loop control, the wheels 40 and 42 are selectively driven bidirectionally, as necessary, so that the lateral edges of the segments cover just one fiber of the fiber pairs 80 and 82 as the segments 101 and 102 are drawn through assembly 30. The axially extending grooves in the lateral surfaces of wheels 40 and 42 permit axial motion of the segments, while resisting lateral movement, except in response to rotary motion of the wheels.
With this configuration, where the position of the lateral edges of the segments is automatically controlled between the drive wheels and the feed dogs, a highly accurate full felled seam may be established, on a continuous basis and without manual intervention. In alternative configurations, the relative positions of the wheels and the optical detectors may be reversed. In some embodiments of the invention, the bias pressure of the wheels 40 and 42 toward their respective platens may be independently varied to provide desired drag forces to the respective material segments passing in the direction of axis 26. With such control, selective stretching of one segment with respect to the other may be attained in a seam.
An alternative configuration embodying the invention is shown generally in FIG. 5. In that configuration, a feed-off-the-arm sewing machine 106 is fitted with a fold assembly 110 and a drive wheel/bias assembly 112. The fold assembly 110 is described below in conjunction with FIGS. 6A, 6B and 6C, and the drive wheel/bias assembly 112 is described below in conjunction with FIGS. 7A, 7B and 7C. In those figures, elements which correspond to elements in FIGS. 1-4 are denoted with identical reference numerals. In operation, limp material segments are folded in assembly 110 and drawn along an axis 114 toward the needles of machine 106.
The fold assembly 110 is shown in detailed form in FIGS. 6A, 6B and 6C. Assembly 110 includes a folder 120 and a sensor assembly 122 of the optical detection system 37. In the illustrated form, folder 120 includes two curved metal elements 123 and 124 that define a pair of oppositely directed V- (or C-) shaped segment guide channels 126, 128 extending along an axis 130' from an input end 120a to an output end 120b. The folder 120 is similar to a type 752-D folder, manufactured by Atlanta Attachment Company, Inc., in which the element 123 has been partially cut away, and a slot 125 has been placed in element 124, in order to accommodate the sensor assembly 122 that is affixed to folder 120 by a screw 126.
The sensor assembly 122 includes a housing 130 and a pair of internally positioned, oppositely directed light emitting diodes 132, 134 and associated pairs of photodetectors 132a, 134a. The housing 130 defines extensions to the segment guide channels 126, 128, and also includes a surface 122a which establishes an extension to the top surface of element 123. The diode/detector pair 132/132a are positioned to detect a limp material segment 142 in the extension to channel 126. The diode/detector pair 134/134a (positioned along a sensing axis passing through the slot 125) are positioned to detect a limp material segment 140 in the extension to channel 128.
A pair of drive wheels 40 and 42 from drive wheel/bias assembly 112, described below in conjunction with FIGS. 7A, 7B and 7C, are adapted to be selectively biased toward or away from the upper surface of element 124 and surface 122a which function as platens.
The drive/wheel bias assembly 112 is shown in FIGS. 7A, 7B and 7C. The assembly 112 includes a support member 148 which is affixed to the sewing machine 106. Assembly 112 also includes drive wheels 40 and 42 (rotatable about axes 40a and 42a, respectively), drive belts 54 and 56, drive shafts 50 and 52, and drive motors 60 and 62, all of which correspond in function to the similarly referenced elements in the configuration of FIG. 1.
The shaft 50 and wheel 40 are positioned on an arm 150 which is pivoted about a first pivot axis 150a and the shaft 52 and wheel 42 are positioned on an arm 152 which is pivoted about a second pivot axis 152a. Linear actuators 160 and 162 are selectively operable to shift the positions of arms 150 and 152 so that the wheels 40 and 42 are biased toward (as illustrated with solid lines in FIG. 7C) or withdrawn (as illustrated in phantom in FIG. 7C) from their respective platens. When the wheels are biased toward their respective platens, positional control of segments 140 and 142 is attained. When the wheels are displaced from their respective platens, the segments 140 and 142 may readily be loaded into or removed from the fold assembly 110.
A controller 100' functions in a similar manner to controller 100 in the configuration of FIGS. 1-4 to control the operation of the sewing head of machine 106 (including sewing head 12 and its associated feed dog assembly), the optical detection system 37 and the position and rotary motion of drive wheels 40 and 42.
FIGS. 8A, 8B and 8C illustrate another alternate form 30' for the fold assembly 30 in the system of FIG. 1. Elements in FIGS. 8A, 8B and 8C which correspond to elements in FIG. 1 are identified by the same reference designations.
The fold assembly 30' includes a rigid central member 210 extending along reference axis 26 from the input end 30a' to the output end 30b'. The input end 30a' of member 210 has a substantially I-shaped cross-section and the output end 30b' has a substantially Z-shaped cross-section. As used herein, the term "I-shaped" refers to a substantially straight line shape, and the term "Z-shaped" refers to a substantially third order curve or piece-wise linear equivalent where the regions at and near the maximum/minimum points are referred to as vertices. The intermediate portions of member 210 have a substantially continuously decreasing Z-shaped cross-section along axis 26 from the output end to the input end. As used herein, the term "continuously decreasing Z-shaped" refers to a shape that substantially continuously changes from Z-shaped to I-shaped.
A rigid upper guide member 212 (shown in broken lines in FIG. 8B), having an inner surface V-shaped cross-section, is positioned above member 210 to establish an upper segment guide channel 36. Similarly, a rigid lower guide member 214, having an inner surface with a V-shaped cross-section, is positioned below member 210 to establish a lower segment guide channel 34. As used herein, the term "V-shaped" refers to a second order curve, or piecewise continuous equivalent where the region at or near the maximum/minimum point is referred to as a vertex.
Optical sensors in members 210, 212 and 214 provide signals representative of the limp material segment position within channels 34 and 36. With the illustrated configuration, the sensors may be positioned between lines D--D and E--E (i.e. near the output end 30b') to permit near-needle segment control. Drive wheels 40 and 42 shown in phantom in FIG. 8B) are affixed to central member 210. The bottom and top surfaces, respectively, of members 212 and 214 are selectively biased toward or away from the wheels. When biased toward the wheels, in response to the sensed position of limp material segments in channels 34 and 36, the wheels are driven to achieve positional control of the limp material segments.
With the configuration of FIGS. 8A, 8B and 8C, the segment guide channels 34 and 36 have adjacent Z-shaped cross-sections near the output end 30b' of fold assembly 30'. As a result, limp material segments positioned in channels 34 and 36 are successively transferred from having adjacent substantially planar cross-sections near the input end 30a', to have adjacent Z-shaped cross-sections at intermediate points between input end 30a' and output end 30b', and to have oppositely-directed, interleaved V-shaped cross-sections near output end 30b'. The control of the limp material segment geometry in this manner permits particularly effective formation of a full-felled seam. For comparison purposes, the segment geometry for limp material segments S1 and S2 in the fold assembly 30' and for fold assembly 110 is shown (along lines A--A through F--F viewed from the input end) in FIGS. 9A and 9B, respectively.
With the illustrated fold assembly 30', material segments bearing relatively high curvature lateral edges (such as a 3-inch radius, 45° arc length, curved edge) may be fed into channels 34 and 36, for example, as illustrated for curved segments S1 and S2 of FIG. 10. Such segments may be drawn through the fold assembly 30' readily and presented to the sewing head to establish a curved full felled seam.
The preferred embodiments of the present invention have been described above in a form adapted for forming a full felled seam at the lateral edges of two limp material segments. In alternate forms, different seam configurations may be attained. For example, a fold assembly may be used which provides only a single segment guide channel and drive wheel, wherein a drive wheel may be used to bidirectionallY control the segment position to establish segment position for a high quality hem. Alternatively, still different fold assemblies may be used to form folded segment geometries for other seams.
The invention can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The described embodiments of the invention are to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. | A seam forming apparatus for forming a seam in one or more limp material segments includes a fold assembly and a driver for positioning the segments within guide channels in the fold assembly prior to presentation to a seam joining device. The driver controls the segments to be at associated predetermined positions within the fold assembly. | 3 |
FIELD OF THE INVENTION
[0001] The present invention relates to a profile bar screen according to the preamble of claim 1 .
[0002] A profile bar screen is used for draining treatment liquor from a suspension of comminuted cellulose material and treatment liquor in an essentially cylindrical digester vessel. This type of profile bar screen is used particularly in continuous digester vessels for producing pulp. Such a profile bar screen can be utilized in new reactors built, or used as spare part in old digesters where existing screen plates needs replacement or if increased withdrawal capacity is needed with larger screen area.
BACKGROUND OF THE INVENTION
[0003] Today, continuous digesters for instance comprise substantially cylindrical pressure vessels arranged in an upright position. Pressure vessels of continuous pulp digesters are remarkably high, and their diameter can be several meters. For instance, the diameter of the bottom part of a pressure vessel may be 4 m to 15 m, all depending upon production capacity of the digester.
[0004] The diameter of such a pressure vessel is usually smaller at the top end of the digester than at its bottom end. However, the diameter of the digester is typically arranged to increase at certain positions in step-outs during the cooking process by means of one or more conical transition sections. The exact positions are defined by process-specific technical grounds and where a change of treatment liquor needs to be made, using withdrawal or extraction screens at these positions. Screens are usually mounted below the above-mentioned step-outs.
[0005] Due to the considerable size of a pressure vessel, deviations from theoretical shapes of a cylinder produced during the manufacture of the pressure vessel, are significant. These deviations from the intended circular cross-section cause many problems. One problem arises, for instance, when the inner surface of the pressure vessel is provided with the screens required. Besides these deviations of the cylindrical shape from manufacturing are the inside of the digester wall exposed to both erosion and formation of deposits during operation of the digester.
[0006] Conventionally, this type of screens are mounted so that the step-out which increases the diameter of the pressure vessel is provided with a screen surface below the step-out such that the internal diameter of the vessel above the step-out is the same or smaller than the internal diameter at the screen area, and below a screen surface is the pulp column allowed to expand in a step-out from the screen area and towards the inside of the pressure vessel. This step-out below a screen surface is made in order to allow the chip column to expand as it may have been compacted over the screen surface during treatment liquor withdrawal. If more than one screen row is arranged in connection with such a step-out is also a smaller step-out arranged between a first upper screen row and a second screen row below, allowing the pulp column to expand and thus improve withdrawal capacity in the second screen row.
[0007] Forces directed to the surface of screens are usually arranged to be transmitted to the cover of the pressure vessel by means of two kinds of support system.
[0008] The first kind of support system is used preferably in sturdy self supporting screens where support only is obtained by a frame bed surrounding a rectangular screen area. This kind of support system has preferably been used for profile bar screens. By such support system could the withdrawal space behind the screens collecting the withdrawn treatment liquor avoid any obstructions which may accumulate deposits, and the withdrawal flow of treatment liquor could be maintained at full capacity over time.
[0009] The second kind of support system, preferably used for slotted screen plates, are support rods, i.e. bars of specific length fixed to the screen plate, arranged between the screen plate and the inside wall of the pressure vessel. This second kind of support system use a multitude of support rods each having to be adjusted to the specific curvature of the vessel wall in order to obtain a support. The asymmetry of the inside wall of the digester's pressure vessel tend to cause problems. Due to the deviations of the cylindrical shape of the pressure vessel, a considerable number of support rods are not supported onto the vessel wall, but at their one end, the support rods are hanging freely in the liquor collection chamber formed behind the screen, which collection chamber is formed between the screen and the interior wall of the pressure vessel. The object of transmitting forces directed to the screen construction to the inner wall of the digester vessel is thus not always achieved by using support rods. Because of the disadvantageous force stress the support rods bend and the screen twists, even breaks. In order to solve this problem could these support rods be made adjustable in order to avoid this problem, which requires a time consuming procedure for adjusting each individual support rod. Installation and replacement of such screen plates with adjustable support rods will be a rather time consuming process.
[0010] Examples of above described solutions could be found in prior art patents.
[0011] In US2003/0095901 is shown a support system for screen plate wherein adjustable support pins are used.
[0012] In US 2005/0284594 is shown a support system for sturdy self supporting profiled bar screens using circular profile bar rods. The profile bar screen is supported by a frame bed surrounding the screen, and horizontal support arches having integrated support shoulders are located at a distance from the digester wall in order to allow a certain ability to move. Similar profiled bar screens is also shown in U.S. Pat. No. 6,889,851 having adjustable support pins.
[0013] In U.S. Pat. No. 5,827,401 is shown yet a support system for sturdy self supporting profiled bar screens using T-shaped profile bar rods, but applied in circular screens. In this design is the force on the screen profile bars transmitted first to a support arch behind rods, and then further to a frame bed located around the circular screen.
[0014] In WO 95/16817 is yet another support system for sturdy self supporting profiled bar screens using T-shaped profile bar rods, but here using horizontally oriented profile bar rods.
[0015] In WO2013105888 is disclosed another self-supporting system for digester screens where the support arch has integrated support shoulders finding support in the outer digester wall at regular intervals and having a slot trough the support shoulders enabling a local deformation such that the support shoulders may find direct contact with the digester shell.
[0016] Profile bar screens are most often preferred as the total withdrawal area (I.e. slot area) are larger than for slotted screen plates, hence the withdrawal capacity per surface area could be higher. However, these profile bar screens are most often made with a sturdy self supporting design where all the force is transmitted to digester wall by a supporting frame bed.
[0017] One more advantage with profile bar screens is that if these have vertical profile bars with vertical slots in-between, could the slots be subjected to a continuous rubbing action from the descending pulp column keeping the slots free from any obstructions, and lower ends of these profile bars could have an unobstructed slot ending allowing any chip fragments caught in a slot from escaping out and away from the slots by the pushing action from the pulp column.
[0018] In digesters having screen areas equipped with screen plates and a multitude of support rods between screen plate and digester vessel wall, are no sturdy frame bed structure at hand which may be used to install sturdy self supporting profiled bar screens. If a profiled screen bar is to be installed in such digester it must have the same support structure with a multitude of support rods, and installation and adaption of each individual support rod becomes time consuming and thus costly. Moreover, flush out of sedimentations behind such screens with support rods during annual shut down for service work becomes difficult as the high pressure jet lances used must penetrat between all rods and direct the flushing action towards each pin. Otherwise must a new frame bed structure be welded into place which is a time consuming process, besides adding additional costs for the frame bed. This requires the mill operator to shut down the digester during annual overhaul work much longer than necessary, if new screens are to be installed.
BRIEF DESCRIPTION OF THE INVENTION
[0019] It is an object of the present invention to prevent the problems in existing solutions when installing profile bar screens in cylindrical digester vessels, such that a still sturdy profile bar screen might be installed quicker and with optimum load support. According to the invention the profiled bar screen could be installed as a replacement screen also in digesters where originally slotted screen plates have been used, and where load support instead has been obtained with a multitude of support pins on the backside of the slotted screen plates, thus having a weaker surrounding frame bed. Previously, when replacing slotted screen plates with profiled bar screens, the entire surrounding frame bed had to be rebuilt, as the profiled bar screens most often had its only load support in surrounding frame bed.
[0020] In order to enable installation also of profile bar screens in screen beds with weaker screen frames, some profiled bar screen also had a multitude of support pins on the backside of the profiled bar screen. Those support pins typically located between support arches and inside of digester wall. But this usage of support pins had the inherent disadvantage with a tedious and time consuming task to adapt the length of each individual support bar. Replacement of digester screens are typically installed during shut down of the digester and the entire pulp production line, which calls for a design enabling an efficient and fast process as any hour of shut-down causes great losses in income from pulp sales.
[0021] According to the invention is thus provided for a profile bar screen for draining treatment liquor from a suspension of comminuted cellulose material and treatment liquor in an essentially cylindrical digester vessel, said profile bar screen being arranged inside the outer wall 1 of the digester vessel forming a withdrawal chamber 20 between the wall of the digester vessel and the profile bar screen, the profile bar screen comprising:
vertical profile bar elements 10 facing the suspension of comminuted cellulose material, said vertical profile bars arranged in parallel to each other and forming a withdrawal slot 15 for treatment liquor between neighboring profile bars; several horizontal support arches 11 having vertical mounting slots for holding a profile bar element in said mounting slots, the horizontal support arches having integrated support shoulders 12 resting against the inside of the outer wall of the cylindrical digester vessel, and each support arch has only two integrated support shoulders located at each respective end of the support arch such that the support arch between support shoulders is located at a distance from the outer digester wall 1 enabling a free unobstructed flow of withdrawn cooking liquor between digester wall and support arch and between support shoulders in each support arch.
[0024] This solution enables a quick installation of the new screen in a digester without having to make any alterations of the pressure vessel wall, and associated 3 rd party testing of new welds. Using only 2 support shoulders in each end of the support arch also provides for path of flow lacking all potential sedimentations on pins or additional support shoulders between ends of the support arch.
[0025] Further, according to a preferred embodiment is each support arch with the two integrated support shoulders made in one single piece from a metal plate with a thickness in the range of 12-18 mm, preferably about 15 mm, said support arch and integrated support shoulders being cut from said metal piece, preferably using water jet or laser cutting. This provides for an less costly and less complicated design of the screen to manufacture.
[0026] In yet a further embodiment is also included in said screen a L-shaped frame 82 with a first and second leg part arranged orthogonally towards each other is attached to the support arch, with the first leg attached to the support arch, preferably by welding, and oriented in the radial direction of the digester and the second leg oriented in the circumferential direction of the digester and with the inwardly facing side of the second leg being flush with the surface of the vertical profile bar elements 10 facing the suspension of comminuted cellulose material kept inside the digester and the outwardly facing side of the second leg abutting a support bar 81 finding final load support in the digester wall. The L-shaped frame provides for a quick confirmation that the support shoulders may need grinding off if the L-shaped frame, due to uneven digester wall, does not come into contact with the support rod to which it is intended to be attached to by welding. If the distance is lets say 3 mm between the L-shaped frame and the support bar, then the support shoulder needs to be ground off the same length.
[0027] In another embodiment is the horizontal support arches of the profile bar screen equipped with additional expansion slots having an open end facing towards the interior of the digester vessel and a closed end in the area of a support shoulder, allowing a flexibility of the horizontal support arches such that support shoulders may rest against the wall of the digester vessel despite any local deviations from a perfect cylindrical shape of the digester vessel wall. The design per se is known from WO2013105888, but is more important to use when having only support shoulders at ends of the support arch, as no other flexing is possible over the length of the support arch. Stress analysis has shown that the largest stress forces developed are those close to support bars, which in themselves are rigid and non flexable.
BRIEF DESCRIPTION OF THE FIGURES
[0028] In the following a preferred embodiment of the invention will be described with reference to the attached drawing, in which
[0029] FIG. 1 shown a continuous digester with cut-away sections in 2 screen areas of the digester;
[0030] FIG. 2 shows a slotted screen plate according to prior art;
[0031] FIG. 3 shows a profile bar screen according to prior art;
[0032] FIG. 4 shows an alternative profile bar screen in a vertical section view according to prior art;
[0033] FIG. 5 shows the profile bar screen as seen in section A-A in FIG. 4 according to prior art;
[0034] FIG. 6 a shows yet another profile bar screen as installed in a screen row with “checkered design” as shown in FIG. 1 with a blind plate in each second screen compartment;
[0035] FIG. 6B shows how a screen row design according to FIG. 6 a may be modified according to prior art with screens also in compartments that previously have had blind plates;
[0036] FIG. 7 show a screen design according to the invention; and
[0037] FIG. 8 a - d shows different profile bars usable in the claimed invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0038] In FIG. 1 is shown a tall and cylindrical continuous digester of a conventional design, with in feed of comminuted cellulose material in upper part and out feed of cooked pulp in bottom. The digester is shown with cut-away sections in 2 screen areas of the digester. In the upper cut-away section are three screen rows shown. Here is the screen area designed with the “checkered” screen area, i.e. with alternating blind plates and screens 61 , 62 , 63 in each screen row.
[0039] The same “checkered” screen area is shown in the lower cut-away section, also with 3 screen rows with alternating blind plates and screens 71 , 72 , 73 in each screen row.
[0040] Essentially the same withdrawal capacity could be obtained with such “checkered” screen if profile bar screens are used instead of slotted plates, as profile bar screens have larger open slot area. The main problem with withdrawal capacity lies in the flow resistance trough the chip (or pulp) bed inside the digester, which could be very high in digesters with a diameter of 10-14 meter. So, a profile bar screen with “checkered” screen area could have same withdrawal capacity as a screen row with slotted screen plates all around the circumference, as the screens are located only some 700-1000 mm apart, which distance is neglect able compared to chip bed distance to center of vessel.
[0041] In FIG. 2 is shown a conventional slotted screen plate 74 according to prior art. A metal plate 75 is equipped with withdrawal slots 76 which are made by either machine milling or water cutting jet technique. The entire screen plate is only supported by a multitude of support rods 78 . In FIG. 3 is shown a conventional profile bar screen 64 according to prior art. Profile bars 66 are supported by horizontal support arches 65 , which in turn is supported by a multitude of support rods 68 . Here is also shown a clean-out plate 69 , which could be opened in order to clean out the lower part of screen assembly. Both these type of screens are shown on page A537 in “Chemical Pulping”, book 6A (1999), ISBN 952-5216-06-3, as screens promoted by Ahlstrom Machinery (now Andritz).
[0042] In FIG. 4 is shown a profile bar screen according to WO2013/105888 as mounted in a continuous digester. The digester wall 1 is the actual pressure vessel wall and inside of the wall is the profile bar screen 2 located with vertical profile bar elements 10 facing the suspension of comminuted cellulose material as it descends down through the digester as a pulp column in the downwards direction PC. The vertical profile bar elements 10 are mounted on several horizontal support arches 11 located preferably at a set vertical distance between each support arch 11 . Thus, the force upon the profile bar screen from the pulp column is first exposed to the profile bar elements 10 and via support arches 11 to the inside of the digester wall 1 .
[0043] As indicated could a blind plate 32 be located above the screen bar elements 10 , supported on a horizontal thrust beam 30 . The upper blind plate 32 has its inwardly facing surface located flush with the inwardly facing surface of the screen bar elements, allowing the descending pulp column to descend without any obstructions to the bar screen area.
[0044] Below the profile bar elements 10 is a guide plate 31 mounted, which in its upper part has a retracted position allowing any chip fragments caught in slots between the profile bar elements from being pushed out from the slots as the pulp column descends.
[0045] The withdrawn treatment liquor is collected in a number of withdrawal chambers 20 between the profile bar elements 10 and the inside of the digester wall. The withdrawal chambers 20 are all in fluid communication with each other and withdrawn treatment liquor will finally be collected in a header chamber 21 located below chambers 20 before being withdrawn from the digester trough an outlet 22 .
[0046] The features of the profile bar screen as shown in WO2013105888 are shown in FIG. 5 . The support arches 11 has on the surface 14 facing the interior of the digester vertical mounting slots for holding a profile bar element 10 (only 3 profile bar elements numbered in figure) in said mounting slots. The profile bar elements have a T-shaped form. The bottom part of the T-shaped profile bar element is mounted in the vertical mounting slots of the horizontal support arches, with the upper flat face of the T-shaped vertical profile bar facing the inside of the treatment vessel and the suspension of comminuted cellulose material contained therein.
[0047] A withdrawal slot 15 is thus formed between profile bar elements 10 . The screen slot size is varying from some 5-6 mm in upper part of digester and down to some 3 mm in lower part of digester, as the cellulose material is subjected to increased delignification and softening during cooking in the digester and slot size needs to be smaller in the final phases of the cook.
[0048] The horizontal support arches 11 further have integrated protruding support shoulders 12 resting against the inside of the outer wall 1 of the cylindrical digester vessel, and in FIG. 5 are 3 such support shoulders 12 shown, each located some distance apart creating an open flow channel 13 connecting the withdrawal chambers 20 to each other.
[0049] According to WO2013105888 are the horizontal support arches 11 equipped with additional expansion slots 16 having an open end 16 a facing towards the interior of the digester vessel and a closed end 16 b in the area of a support shoulder 12 , allowing a flexibility of the horizontal support arches such that all support shoulder may rest against the wall of the digester vessel despite any local deviations from a perfect cylindrical shape of the digester vessel wall.
[0050] In the shown embodiment could some 12 profile bar elements be mounted between 2 neighboring expansion slots, but could be as few as 10 or as many as 20. The non flexing part of the support arch would thus hold the profile bar elements fixed in relation to each other and the withdrawal slot 15 thus kept constant. The withdrawal slot 15 coincident with the expansion slot 16 would instead allow some alteration of the slot width as the support arch will flex. However, the impact of this alteration is low, and if for example 10 profile bar elements are mounted between two expansion slots will only 10% of slot area be subjected to alteration due to flexing of the support arch. The relative alteration of individual slots will decrease with less profile bar elements between expansion slots as flexing due to uneven cylindrical form of vessel will be distributed over more expansion slots.
[0051] The expansion slots preferably has a depth X trough the horizontal support arches exceeding the depth Y of the horizontal support arches 11 in the area of the support arches wherein no support shoulder is located radially outside of the support arches.
[0052] The length X of the expansion slots preferably exceeds 50% of the total depth Z of the horizontal support arches 11 , as counted from the inwardly facing surface 14 of the support arches 11 and to the outwardly facing surface of the support shoulder 12 of the support arches 11 .
[0053] The depth of the support shoulder (Z-Y in FIG. 5 ) could vary depending upon the depth of the chambers 20 in each individual digester.
[0054] In order to avoid stress cracking due to local stress load as the support arch 11 will flex is the closed end 16 b of the expansion slot preferably widened with an essentially circular slot part with a radius exceeding 4 millimeter as shown in principle in FIG. 5 .
[0055] The expansion slot 16 could have a width being substantially constant before mounting the profile bar screen in said digester vessel or alternatively have a larger width at the open end 16 a facing towards the interior of the digester vessel than the width at the closed end 16 b before mounting the profile bar screen in said digester vessel. The alternative with increasing width towards open end 16 a could preferably be used when the digester vessel is expected to have a form that deviates more from a perfect cylindrical form, thus needing more flexing in the support arch 11 . Thus, with increasing width the slot could be some 1 mm at closed end 16 b and some 2-4 mm at open end 16 a.
[0056] In FIG. 6 a is disclosed a screen design as used according to prior art in checkered screen rows as disclosed in FIG. 1 . In this design is the screen comprising a self-supporting sturdy support arch 11 , having slots for mounting the individual screen bars 10 . A L-shaped frame 82 surrounds the screen area, attached to the support arch by fillet welds. The support arch 11 finds its load support in a number of support members 80 welded to the digester wall with fillet welds 90 . There are typically a multitude of support members 80 located over the height of the screen, and in numbers corresponding to the number of support arches 11 shown in FIG. 4 . As each such support member 80 is welded to a part of the pressure vessel, each weld 90 has to be inspected by a third party certification member for appropriate approval of the pressure vessel design. The fillet weld also prevents penetration of corrosive cooking liquors between the support members 80 and the pressure vessel wall 1 , and needs to be continuous around the entire support member. Such inspection needs most often crack inspection of the weld 90 using either penetrants or magnaflux methods or similar, thus needing extensive time and review for all welds. There is also a vertical support bar 81 which provides support for the L-shaped frame 82 , with a fillet weld 92 around the circumference of the L-shaped frame, and with a fillet weld 91 attached firmly to the support member 80 . A screen section could thus be replaced if needed without any changes in the pressure vessel wall design, as only welds 92 need to be removed with a grinding disc or similar. The support members 80 are only extended towards the withdrawal compartment 20 such that necessary support area is obtained for the support arches 11 . In the next compartment, covered by a blind plate 84 , the blind plate has support pins 88 arranged in a similar way as disclosed in FIG. 2 . Now, if the operating conditions of the digester need increased withdrawal capacity there is an option to replace the blind plates with screen sections. How this is conventionally implemented is shown in FIG. 6 b , where the blind plate 84 is removed. What is needed here is an additional support member 80 e extending the support area for new support arch 11 stretching over the compartment previously covered by a blind plate. The L-shaped frame 82 and the individual screen bars 10 are not shown in this drawing for the new screen, but is of course included in the final design. The additional support member 80 e needs to be welded around the entire circumference with a fillet weld 90 e . This conventional design has the drawbacks that the welding work is time consuming and the additional welds needs thorough inspection before approval as a change in the pressure vessel design is made, besides high expenses for welding material/electrodes. In a typical digester with 4 screen rows needing replacement of the blind plates, FIG. 1 show 6 screen rows with checkered screen area, is over 1000 support members installed, thus requiring installation of over 1000 additional support members 80 e . A certified welder may apply one weld for one additional support member in 5-10 minutes, and hence the total welding work alone may require in excess of 100-200 man hours. Then the necessary time for inspection using penetrant or magnaflux methods may require additional time in the same order. After inspection work could the installation of the new screens start, which takes additional time to complete the rebuild.
[0057] This amount of time is normally not available in the short down time of a digester where maintenance or rebuild work needs to be finished.
[0058] The inventive screen design is shown in FIG. 7 , and avoid any alterations in the digester shell when installing the new screen. As no changes in the pressure vessel is made, no welds need to be inspected by a third party certification member for appropriate approval of the changed pressure vessel design. The screen design is similar to that disclosed in WO2013105888 but differs in that only two support shoulders 12 are located at each end and integrated with the support arch 11 . The support arch 11 is preferably made with somewhat larger dimension Y′ than the corresponding dimension Y in FIG. 5 , and the thickness of the support arch 11 is preferably extended from some 8 mm to about 15 mm. As indicated previously has not the digester a perfect circular form so the distance between the inner facing side of the support bar 81 and the inside of the digester wall 1 may change, but this may be compensated by delivering the screen with somewhat oversized support shoulder 12 in the radial direction. If the outer L-shaped frame 82 is not abutting the support bar 81 , could excess material easily be ground off from the support shoulder at site, and as there are only 2 support shoulders on each support arch 11 is less adjustment time necessary during installation. Besides a dramatic reduction in necessary installation time will the screen design according to the invention provide with less hindrance for the downward flow of the withdrawn spent cooking liquors in the withdrawal compartment 20 , and less amount of surfaces where the spent cooking liquors could form depositions precipitated from the spent cooking liquors.
[0059] The entire support arch 11 and integrated support shoulders 12 is preferably made in one single piece, preferably cut from about 15 mm thick metal plates using water jet or laser cutting techniques.
[0060] The invention is preferably applicable for screens with an arch length AL in the circumferential direction of the digester in the range of 200-600 mm. The screens are in a first installation made with an arch length of about 495 mm and expected to be put into operation late 2014.
[0061] The length SL in the circumferential direction of the digester of the support shoulders 12 when made from a single sheet metal piece are preferably in the range 20-60 mm, preferably 40 mm, and in relation to the total arch length AL less than 10%, leaving a large unhindered flow channel 13 between support shoulder 12 less exposed for sedimentations to build up.
[0062] In a most preferred embodiment is the outer edge of the support shoulder closest to digester wall and closest support member 80 designed with a large radius R 1 that provides clearance to any fillet welds 90 , and said radius exceeding 10 mm, preferably 15 mm. The inner edge of the support shoulder closest to flow channel 13 and furthest away from the support member 80 is preferably designed with a smaller radius R 2 , and said radius exceeding 3 mm, preferably 5 mm and at the most same as R 1 . The object of the smaller radius is to avoid a sharp edge from penetrating the pressure vessel wall 1 . The clearance between outer edge of support shoulders 12 and support member 80 should preferably be kept at a minimum, and only made so large that it may accumulate any local dislocation of for example the support member in form of burrs or weld spots. No withdrawal flow is intended to be developed in this clearance and it will most likely be blocked by sedimentations after only a short time of operation, which will happen even if the clearance would be as large as 10-30 mm, at expense of reducing the major withdrawal flow channel 13 .
[0063] But in an alternative solution could also the support shoulders be attached to the support arch as a separate piece, and preferably attached by welding. Alternatively could the support shoulders be designed as adjustable screws that after adjustment is locked by a weld, but both these alternatives result in a more expensive screen.
[0064] As is the case in the design according to WO2013105888 are the support arches 11 preferably equipped with additional expansion slots 16 having an open end 16 a facing towards the interior of the digester vessel and a closed end 16 b in the area of a support shoulder 12 , allowing a flexibility of the horizontal support arches such that the 2 support shoulders may rest against the wall of the digester vessel despite any local deviations from a perfect cylindrical shape of the digester vessel wall.
[0065] It is to be understood that the above description and the related figures are only intended to illustrate the present solution. Thus, the solution is not restricted only to the embodiment described above and defined in the claims, but many different variations and modifications, which are possible within the scope of the idea defined in the attached claims, will be obvious to a person skilled in the art.
[0066] Thus the profile bar screen may preferably be used in other cylindrical pressure vessels such as digesters, either in continuous or batch digesters with a cylindrical form. In FIGS. 8 a -8 d are shown different types of profile bars that could be used.
[0067] In FIG. 8 a is shown a profile bar with vertical profile bar elements having a closed Y-shaped form, with bottom part of the Y-shape mounted in the vertical mounting slots of the horizontal support arches for holding a profile bar element in said mounting slots, and with the upper flat face of the closed Y-shaped vertical profile bar facing the inside of the treatment vessel and the suspension of comminuted cellulose material contained therein.
[0068] In FIG. 8 b is shown a profile bar with vertical profile bar elements 10 b having a circular form facing the interior of the digester, with an integrated flat bar portion at its bottom part mounted in the vertical mounting slots of the horizontal support arches for holding a profile bar element in said mounting slots, and with the upper faces of the circular bars facing the inside of the treatment vessel and the suspension of comminuted cellulose material contained therein.
[0069] In FIG. 8 c is shown a profile bar with vertical profile bar elements 10 c having a T-shaped form, with bottom part of the T-shaped bar mounted in the vertical mounting slots of the horizontal support arches for holding a profile bar element in said mounting slots, and with the upper flat face of the T-shaped vertical profile bar facing the inside of the treatment vessel and the suspension of comminuted cellulose material contained therein. But in this embodiment is each second bar element a flat bar element 10 c″.
[0070] In FIG. 8 d is shown an alternative profile bar arrangement according to FIG. 8 c , but where each second bar element is recessed a distance B from the upper flat face of neighboring T-shaped bar elements. | The invention relates to an improved profile bar screen for draining treatment liquor from a suspension of comminuted cellulose material and treatment liquor in an essentially cylindrical digester vessel. According to the invention is a profile bar screen designed with horizontal support arches 11 with integrated support shoulders 12 only at the outer ends of the support arch which support shoulders rest against the inside of the vessel wall 1 . The invention combines the techniques from self-supporting screens with support members of weaker screen designs, avoiding need to make any additional welds in the classified pressure vessel wall of the digester. Installation of new screens in compartments previously equipped with blind plates in checkered screen rows may be done quickly and at less costs during shorter down time of digester. | 3 |
RELATED APPLICATIONS
Ser. No. 301,667, filed Sept. 14, 1981, by the same inventors as herein and assigned to the same assignee.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to inhibition of metal corrosion in acidic solutions, and particularly to improved aqueous reaction products for such use.
2. Description of the Prior Art
In the field of oil-well acidizing, it is necessary to use inhibitors to prevent corrosion of the oil-well equipment by the acid solutions employed. Many different acetylenic amines have been proposed or used as corrosion inhibitors for oil-well acidization; see e.g. U.S. Pat. Nos. 2,997,507; 3,079,345; 3,107,221; 3,231,507; 3,268,524; 3,268,583; 3,382,179; 3,428,566; 3,496,232; 3,705,106; 3,772,208; 3,779,935; 3,802,890; 3,816,322; and 4,002,694; and the articles entitled "Ethynylation" by W. Reppe, et al. Ann. Chem. 59B, 1-224 (1955); and "Acetylenic Corrosion Inhibitors", by Foster et al., Ind. and Eng. Chem., 51, 825-8 (1959).
Nonetheless, there has been a continuing search for new materials which are highly effective in such application. More particularly, it is desired to provide new and improved corrosion inhibitors which are particularly advantageous in commercial use to prevent corrosion of metals in highly acid solutions, even after prolonged periods of use, which have a low vapor pressure and relatively high stability so that they can be employed at the high temperatures which prevail in modern deep drilling operations, which function effectively at low concentrations, and which are relatively inexpensive to make.
SUMMARY OF THE INVENTION
The corrosion inhibitor composition of the invention is the reaction product of the catalytic ethynylation reaction between a dialkylamine, a substituted benzaldehyde, and acetylene, and is a complex material which contains predominately a 3-dialkylamino-3-(substituted phenyl)prop-1-yne.
DETAILED DESCRIPTION OF THE INVENTION
The predominate compound in the reaction product is formed by the reaction shown below: ##STR1## where
R 1 and R 2 are independently alkyl C 1 -C 8 ;
R 3 is independently halo, alkyl C 1 -C 8 or alkoxy C 1 -C 8 ; and
n is 1 or 2.
The ethynylation reaction product is a complex mixture which probably contains, in addition to the predominate compound, the corresponding bis compound, i.e. an N,N,N',N'-tetralkylamino-1,4-bis(substituted phenyl)-1,4-(2-butynediyl)diamine, having the formula: ##STR2## In addition, it may contain some 3-dialkylaminobutyne, having the formula:
R.sub.1 R.sub.2 NCH(CH.sub.3)C.tbd.CH,
and, depending upon reaction conditions, unreacted starting materials, and lesser amounts of other materials.
The reaction product is particularly attractive from a commercial standpoint since purification of the product of the ethynylation reaction is not required. Furthermore, the reaction product itself usually performs as well as or better under most conditions than the predominate compound in pure form. This effect may be due to the presence of by-products in the reaction product which may act as a synergist with the predominate compound.
The reaction is carried out in the presence of an ethynylation catalyst, such as is used for commercial preparation of butynediol; see, e.g. U.S. Pat. Nos. 3,920,759; 4,117,248; and 4,119,790. The preferred catalyst is a complex cuprous acetylide prepared from a precursor containing about 5 to 35% by weight of copper, and 2-3% by weight of bismuth, as the oxides, on a magnesium silicate carrier. However, many other ethynylation catalysts and carriers known in the art may be used as well.
The ethynylation reaction can be run under low or high pressure conditions, i.e. a partial pressure of acetylene, as is used for butynediol, generally from about 0.1 atmosphere to 20 or more atmospheres, either in a stirred reactor with a slurried catalyst, or in a fixed bed, through which the acetylene and the solution are passed.
The ethynylation process preferably is run in a solvent in which the reactants are at least partially soluble. An organic solvent which is inert to the reaction may be used advantageously; preferably it is also volatile so that it can be easily separated from the reaction product by distillation. Alcohols, hydrocarbons and other organic solvents may be used for this purpose. Preferred organic solvents are either dry or aqueous isopropanol or methanol.
Water also is a suitable solvent; however, water does not completely dissolve the reactants, and it wets the catalyst, which interferes with wetting by the organic reactants. The ethynylation reaction rate thus is slower in water than in an organic solvent which forms a single liquid phase. Mixtures of an organic solvent and water may be used, most suitably those which give a single reacting liquid phase.
In a typical run, a charge is made of the reactants in a molar ratio of about 1:1 of the dialkylamine and substituted benzaldehyde. The charge then is heated to a temperature of about 70° to 115° C., preferably 85° to 105° C., and acetylene is introduced and maintained at the desired pressure. The reaction then is carried out for from less than 1 to 36 hours, generally for about 0.2 to 8 hours.
The crude reaction product then is separated from the catalyst, where necessary, and, preferably, stripped of solvent, usually under reduced pressure.
The predominate compound in the reaction product may be characterized by its IR and NMR spectra. The IR spectrum shows the presence of a strong sharp C-H stretching absorption band at about 3320 cm -1 , attributable to the ethynyl group, and an absence of carbonyl absorption in the region of 1600-1700 cm -1 . The NMR spectrum shows distinctive absorptions related to the ##STR3## portion of the molecule. The C-1 proton is evident by a doublet at 3.1-5.2δ due to coupling of the C-3 proton with the C-1 proton. The C-3 proton also shows up as a doublet for the same reason; however, at 2.0-3.0δ. In addition, the NMR spectrum of the compound reveals the absence of both an aldehyde proton absorption, which is present in the starting material at 9-10δ, and an N-H absorption.
The corrosion-inhibiting product of the invention may be used at varying concentrations. What is an effective amount in a particular application will depend upon local operating conditions. For example, the temperature and other characteristics of the acid corrosion system will have a bearing upon the amount of inhibitor to be used. The higher the temperature and/or the higher the acid concentration, the greater is the amount of corrosion inhibitor required to give optimum results. In general, however, it has been found that the corrosion inhibitor of the invention should be employed at a concentration of between 0.01 and 2%, preferably between 0.01% and 1.2%, by weight of an aqueous acidic solution, although higher concentrations can be used when conditions make them desirable. An inhibitor concentration between 0.05% and 0.75% by weight is of the most general use, particularly at elevated temperatures, e.g. in the neighborhood of 200° F.
The acidic solution itself can be dilute or concentrated as desired, and can be of any of the specific concentrations customarily used in treating metals, e.g. ferrous metals, or for operations involving contact of acidic solutions with such metals in oil-well acidizing. Generally the acid content is about 5 to 80%, and, in most operations of the character indicated, acid concentrations of 10-15% by weight are employed. Non-oxidizing inorganic acids are the most common acids used.
The invention will now be described in more detail by the following examples which are for illustration only, and not by way of limitation.
EXAMPLE 1
A charge is made to a 1-l. stirred autoclave consisting of 1 mole (129 g) of dibutylamine, 1 mole of 2-chlorobenzaldehyde (140 g), 25 g of a 35 wt. % Cu-containing catalyst, prepared as described in U.S. Pat. No. 4,119,790, as a powder, and 350 ml of isopropanol.
The reactor is purged well with nitrogen, released to atmospheric pressure, and the reactants are heated to 95° C. The vapor pressure at this point is recorded. Acetylene then is admitted at a pressure of 100 psig above the recorded pressure. The amount of acetylene furnished to the reaction is measured by the loss in weight of the supply cylinder.
After about 12 hrs., corresponding to the absorption of 1 mole of acetylene (26 g), the reactor is cooled and the product is discharged. The reaction mixture is filtered to remove catalyst and stripped of solvent by rotary evaporation.
Gas chromatographic analysis of the resulting crude reaction product mixture indicates it contains about 65% by weight of 3-dibutylamino-3-(2-chlorophenyl)prop-1-yne.
The IR spectra of this compound shows a sharp band at 3340 cm -1 ; the NMR spectrum contains distinctive doublets at 5.1 and 2.9δ in addition to absorptions associated with the butyl and 2-chlorophenyl groupings.
EXAMPLES 2-6
Using the same procedure as described in Example 1 except that an equal molar charge of the following dialkylamines and substituted benzaldehydes are used in place of dibutylamine and 2-chlorobenzaldehyde. The predominate reaction product compound also is indicated, and it is present in comparable amounts in the reaction product as in Example 1.
(2) Dimethylamine and 4-chlorobenzaldehyde; dimethylamino-3-(4-chlorophenyl)prop-1-yne.
(3) Dibutylamine and 4-methoxybenzaldehyde; dibutylamino-3-(4-methoxyphenyl)prop-1-yne.
(4) Dibutylamine and 2,4-dichlorobenzaldehyde; dibutylamino-3-(2,4-dichlorophenyl)prop-1-yne.
(5) Dibutylamine and 4-chlorobenzaldehyde; dibutylamino-3-(4-chlorophenyl)prop-1-yne.
(6) Dihexylamine and 2-chlorobenzaldehyde; dihexylamino-3-(2-chlorophenyl)prop-1-yne.
The reaction products of the present invention were tested in the usual way to determine their effectiveness as corrosion inhibitors. In such tests, strips of 1020 carbon steel of the dimensions 2.5"×1.0"×0.20" were first degreased with methylethyl ketone and then descaled by soaking in 10% hydrochloric acid solution containing approximately 0.1% propargyl alcohol. The coupons then were cleaned with a brush and thoroughly rinsed with water. After rinsing, the coupons were soaked in 2% sodium carbonate solution, rinsed successively with water and acetone and air dried. The surface dimensions of the cleaned coupons were determined and the coupons were allowed to dry in a desiccator. Before use the coupons were weighed on an analytical balance.
The tests were carried out in a 4 oz. jar containing a weighed amount of the inhibitor. The total solution weight was taken to 100.0 g with the addition of 15% hydrochloric acid. The coupon then was placed in the mixture and the jar loosely capped and placed in a 80° C. oil bath. After 16 hours the jar was removed from the oil bath and the contents were allowed to attain ambient conditions. The coupon was removed from the acid solution, thoroughly washed with water, 2% sodium carbonate solution, again with water, and finally rinsed with acetone. After air drying the coupon was kept in a desiccator before weighing and the net weight loss was calculated by the established procedure.
A control also was run using no inhibitor whatsoever, and for comparative purposes, with a reaction product containing dimethylamino-3-phenyl-prop-1-yne, an unsubstituted phenyl compound, prepared by ethynylation of dimethylamine and benzaldehyde.
The test results are presented in the Table below, where a lower value of weight loss represent good corrosion inhibition.
TABLE______________________________________EFFECTIVENESS OF REACTION PRODUCT OFINVENTION AS CORROSION INHIBITORSCompound of Formula R.sub.1 & R.sub.2 ##STR4## Conditions of Test Loss (%)Wt.______________________________________Butyl 2-Chlorophenyl 0.4% Inhibitor; 0.06 37.5% HCl; 4 hrs; 80° C.Ethyl 2-Chlorophenyl 0.4% Inhibitor; 0.17 37.5% HCl; 4 hrs; 80° C.Hexyl 2-Chlorophenyl 0.4% Inhibitor; 0.33 37.5% HCl; 4 hrs; 80° C.Methyl 4-Chlorophenyl 0.4% Inhibitor; 0.49 37.5% HCl; 4 hrs; 80° C.No Inhibitor 0.4% Inhibitor; 50.94 37.5% HCl; 4 hrs; 80° C.Butyl 2-Chlorophenyl 0.4% Inhibitor; 0.19 37.5% HCl; 16 hrs; 80° C.Methyl Phenyl* 0.4% Inhibitor; 14.25 37.5% HCl; 16 hrs; 80° C.No Inhibitor 0.4% Inhibitor; 54.90 37.5% HCl; 16 hrs; 80° C.Butyl 2-Chlorophenyl 0.4% Inhibitor; 0.03 15% HCl; 16 hrs; 80° C.Butyl 4-Chlorophenyl 0.4% Inhibitor; 0.04 15% HCl; 16 hrs; 80° C.Methyl 4-Chlorophenyl 0.4% Inhibitor; 0.09 15% HCl; 16 hrs; 80° C.Butyl 2,4-Dichlorophenyl 0.4% Inhibitor; 0.07 15% HCl; 16 hrs; 80° C.Butyl 2-Methoxyphenyl 0.4% Inhibitor; 0.07 15% HCl; 16 hrs; 80° C.Methyl Phenyl* 0.4% Inhibitor; 0.12 15% HCl; 16 hrs; 80° C.No Inhibitor 0.4% Inhibitor; 26.50 15% HCl; 16 hrs; 80° C.______________________________________ *Comparative tests
As is seen from the data in the Table, the reaction products of the invention exhibit excellent corrosion inhibition for metal in aqueous acid solution. These products perform substantially better than the corresponding reaction products containing unsubstituted phenyl compounds, particularly under the conditions of high concentrations of acid, and long periods of exposure, which conditions are used in commercial applications.
While the invention has been described with reference to certain embodiments thereof, it will be understood that modifications and changes may be made which are within the skill of the art. Accordingly, it is intended to be bound by the following claims in which: | A corrosion inhibitor for aqueous solutions of mineral acids consisting essentially of the reaction product obtained by the catalytic ethynylation of a dialkylamine, a substituted benzaldehyde and acetylene, said reaction product being a complex material which contains predominately a 3-dialkylamino-3-(substituted phenyl) prop-l-yne. | 8 |
FIELD OF THE INVENTION
[0001] The present invention relates to a plant nutrition, and more particularly to a plant nutrition formulated by recovery filtrate from non-woody fiber plant biopulp and formulating method thereof.
BACKGROUND OF THE INVENTION
[0002] Traditionally, farmers apply agricultural chemicals to prevent crops from being infected by the pathogens, which will increase the yield of the crops and reduce the possibility of plant disease infection. When the agricultural chemicals are utilized in a high concentration or in the late harvest period, the residue of agricultural chemicals left on the crops will be resulted in. An acute poison will cause damage on the human health by accumulating high concentration of the agricultural chemical in the body.
[0003] The present invention uses the recovery filtrate from non-woody fiber plant biopulp to formulate a plant nutrition for the crop cultivation. The rice straws, sugarcane residues and woods have been used as the materials for producing the paper pulp by chemical methods in the past. The waste water discharged from the papermaking factories is the major pollution source of the papermaking industry. This is a troublesome problem that is unable to be solved all the time. The present invention uses a biopulping method to produce the pulp fiber for papermaking. The recovery filtrate from the biopulp is not harmful to the germinations of the crop seeds and can be formulated to a plant nutrition solution. This plant nutrition is contributive to the crop development. Therefore, the present invention not only solves the environmental pollution problem but also provides a way for the resources recycling. This is a great achievement and breakthrough for the traditional chemical pulping processes.
[0004] The yield of rice straws is about 2.35 million tons every year in Taiwan. The organic components in rice straws are almost more than 95%. The organic components include 41.3% carbon, 0.81% nitrogen, 20.6% hemicellulose, 24.7% cellulose and 7.7% lignin. Generally, the ways for handling the waste rice straws include manufacturing them into straw ropes, straw bags, straw mats and cardboards, serving them as covering material for a plot of land, using them as a fuel, and mixing them with other materials to produce compost. Also, the rice straws could be directly buried in soil or burned for recyclably using the nutrition. Most of the waste rice straws are locally burned or directly buried in soil in modern society since the cost for manufacturing the rice straws into bags or mats is pretty high. When the waste rice straws are locally burned by the farmers, it not only easily results in the environmental pollution but also wastes the useful resources. Since the rice straws include abundant fibers, the soil fertility can be largely improved if the waste rice straws are buried in soil. However, the waste rice straws are usually not completely decomposed by the microorganisms under anaerobic environment, which results in the generation of organic acids such as acetic acid and phenolic acid, and etc. Nevertheless, these matters are harmful to the crop growth. The present invention provides a method that the waste rice straws are inoculated with the microorganisms under aerobic condition for fermentation and producing the biopulp and then the recovery biopulp filtrate is processed and manufactured into the product helpful to the crop development. In such a way, the waste would not cause environmental pollution.
[0005] Another aspect, character and executive adduction of the present invention will become more completely comprehensible by the following revelation and accompanying claim.
SUMMARY OF THE INVENTION
[0006] It is therefore an object of the present invention to provide a plant nutrition and formulating method thereof, and more particularly, a plant nutrition formulated by recovery filtrate from non-woody fiber plant biopulp and the formulating method thereof. The plant nutrition is helpful to the germination and enhances the growth of the plants.
[0007] It is an object of the present invention to provide a plant nutrition and method thereof. The present invention not only solves the environmental pollution problem but also provides a way for the resources recycling. This is a great achievement and breakthrough for the traditional chemical pulping processes.
[0008] In accordance with an aspect of the present invention, a method for formulating a plant nutrition is provided. The method includes steps of providing a biopulp of a non-woody fiber plant, filtrating the biopulp for preparing a filtrate and formulating the filtrate for preparing the plant nutrition.
[0009] Preferably, the biopulp is provided by steps of providing a culture solution with a culture medium, a non-woody fiber plant and a suspension of a microorganism, and fermenting the culture solution for preparing the biopulp.
[0010] Preferably, the non-woody fiber plant is pretreated by one selected from a group consisting of a relatively higher pressure treatment under a relatively higher temperature, a steamed treatment under a relatively higher temperature, a boiled treatment under a relatively higher temperature, a fumigatory treatment and a soaked treatment under a room temperature.
[0011] Preferably, the microorganism is one selected from a group consisting of a Bacillus licheniformis (PMBP-m5), a Bacillus subtilis (PMBP-m6) and a Bacillus amyloliquefaciens (PMBP-m7).
[0012] Preferably, the microorganism has an inoculation concentration ranged from 0 to 108 cfu/ml.
[0013] Preferably, the fermenting process is proceeded at a temperature ranged from 20 to 50° C.
[0014] Preferably, the fermenting process is proceeded over 0˜10 days.
[0015] Preferably, the step of fermenting the culture solution for preparing the biopulp further includes a step of boiling the biopulp for 25˜40 minutes under 120˜150° C.
[0016] Preferably, the biopulp further includes 0˜4% (w/v) CaO when being boiled.
[0017] Preferably, the biopulp is screened by 18˜300 meshes.
[0018] Preferably, the filtrate is diluted by a volume of 10˜100 times for being applied to a crop cultivation.
[0019] Preferably, the method further includes a step of adding an additive for preparing an improved plant nutrition, wherein the additive is one selected from a group consisting of a seaweed powder, an urea, an alcohol, a Hoagland's solution and a mixture thereof.
[0020] Preferably, the improved plant nutrition is diluted by a volume of 250˜1000 times for being applied to a crop cultivation.
[0021] In accordance with another aspect of the present invention, a method for formulating a plant nutrition is provided. The method includes steps of providing a biopulp of a fiber plant, filtrating said biopulp for preparing a filtrate and formulating the filtrate for preparing the plant nutrition.
[0022] Preferably, the biopulp is provided by steps of providing a culture solution with a culture medium, a fiber plant and a suspension of a microorganism, and fermenting the culture solution for preparing the biopulp.
[0023] Preferably, the fiber plant is a non-woody fiber plant.
[0024] In accordance with another aspect of the present invention a formulated plant nutrition is provided. The plant nutrition includes a filtrate of a biopulp of a non-woody fiber plant, a nitrogen source, an alcohol and a Hoagland's solution.
[0025] Preferably, the plant nutrition further includes a polymer.
[0026] Preferably, the polymer is one selected from a group consisting of a seaweed powder, an alginic acid, an alginic salt, a polyelectrolyte, a corn wheat bran and a starch.
[0027] Preferably, when the filtrate is 100 parts by volume, the polymer is added therein by a volume of 0.1˜5 parts, the nitrogen source is added therein by a volume of 0.01˜1 parts, the alcohol is added therein by a volume of 0.1˜5 parts and the Hoagland's solution is added therein by a volume of 0.1˜5 parts.
[0028] Preferably, the nitrogen source is a urea.
[0029] The above objects and advantages of the present invention will become more readily apparent to those ordinarily skilled in the art after reviewing the following detailed descriptions and accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] FIG. 1 shows the ability of various strains to decompose the rice straw of Japonica rice;
[0031] FIG. 2 shows the effects of the biopulp filtrates at 50-fold dilution on the germination of lettuce seeds according to a preferred embodiment of the present invention;
[0032] FIG. 3 shows the effects of the biopulp filtrates at 50-fold dilution on the growth of lettuce according to a preferred embodiment of the present invention;
[0033] FIG. 4 shows the effects of the biopulp filtrates at 50-fold dilution on the growth of lettuce according to a preferred embodiment of the present invention;
[0034] FIG. 5 shows the effects of the biopulp filtrates of different dilution folds on the growth of cucumber seedlings according to a preferred embodiment of the present invention;
[0035] FIG. 6 shows the effects of different RSL plant nutrition concentrations on the growth of cucumber seedlings according to a preferred embodiment of the present invention; and
[0036] FIG. 7 shows the information about the growth of cucumber seedlings after being treated with RSL plant nutrition three times according to a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0037] The present invention will now be described more specifically with reference to the following embodiments. The present invention is to provide a plant nutrition formulated from the recovery filtrate of the biopulp of the waste rice straws. The material is waste rice straw. The detail steps are as follows.
[0038] (A) The preparation of waste rice straws for testing:
[0039] The waste rice straws of an Indica rice ( Oryza sativa L. subsp. indica) and Japonica rice are provided. The variety of the Indica rice is Taichung Sheng No. 10 and that of the Japonica rice is Tai Keng No. 9. The rice straws are sun-dried, cut into small segments of 2-3 cm length and pretreated in different ways. The detail steps are described as follows. The waste rice straws are pretreated by an autoclaved treatment (121° C., 15 lb/in 2 for 15 minutes), a steamed treatment under relatively high temperature (100° C. for 60 minutes), a boiled treatment under a relatively high temperature (100° C. for 30 minutes), or a soaked treatment under room temperature (25˜30 ° C. for 30 minutes) respectively.
[0040] (B) The selection of bacterial strains having decomposition ability:
[0041] The microorganism strains are obtained by the following method according to a preferred embodiment. First, 10 g of the rice straws and 10 g of livestock excrements are prepared and added into 90 ml of sterile water containing agar (0.1%, w/v). The materials are well mixed and a serious dilution is made. Then, 0.1 ml of 10 3 X and 10 4 X diluted solution are uniformly spread on Nutrient Agar plate, pH 8 (NA, purchased Nutrient Agar from Difco company) and Potato Dextrose Agar plate, pH 8 (PDA, purchased Potato Dextrose Agar from Difco company) respectively. Next, the plates are placed in the incubators under 30° C. and 50° C. for 24 hours and 48 hours respectively. Single colonies grown on plates are picked and isolated for obtaining the microorganism strains. The number of microorganisms isolated from the rice straws and the livestock excrements having the decomposition ability is more than 200 strains. Finally, the microorganisms are identified by the Gram stain. It is found that most of the microorganisms are Gram-positive bacteria.
[0042] The isolated microorganisms are further selected by the following steps for selecting the microorganism strains having the decomposition ability for rice straws. (1) 19 strains of the isolated strains, named PMBP-m1, PMBP-m2, PMBP-m3, PMBP-m4, PMBP-m5, PMBP-m6, PMBP-m7, PMBP-O1, PMBP-O2, PMBP-O3, PMBP-O4, PMBP-e1, PMBP-e2, PMBP-e3, PMBP-e4, PMBP-H1, PMBP-H2, PMBP-H3 and PMBP-H4 (as shown in Table 1), are divided into 9 strains groups, including PMBP-I, PMBP-II, PMBP-III, PMBP-IV, PMBP-V, PMBP-VI, PMBP-O, PMBP-E and PMBP-H. Please refer to Table 1, which shows the bacterial strains of different strain groups and the characteristics thereof. (2) The strains groups are cultured with NA plates respectively and then a suspension of microorganism is prepared at the concentration of 10 8 cfu/ml. (3) 100 ml of solution containing rice straws of Japonica rice (5%, w/v) is prepared. (4) 1 ml of the microorganism suspension is added into the sterile solution prepared in step (3) and then cultured under 50° C. and 200 rpm shaking for a week. Each strain is set up in duplicate. (5) The decomposition percentage of rice straws is calculated.
[0000]
TABLE 1
Characteristics
Isolate
Temp. 50° C.
pH 8
Gram stain (+/−)
PMBP-m1
++
+
+
PMBP-m2
++
+
+
PMBP-m3
++
+
+
PMBP-m4
++
+
+
PMBP-m5
++
+
+
PMBP-m6
++
+
+
PMBP-m7
++
+
+
PMBP-O1
++
+
+
PMBP-O2
++
+
+
PMBP-O3
++
+
+
PMBP-O4
++
+
+
PMBP-e1
++
+
+
PMBP-e2
++
+
+
PMBP-e3
++
+
+
PMBP-e4
++
+
+
PMBP-H1
++
+
+
PMBP-H2
++
+
+
PMBP-H3
++
+
+
PMBP-H4
++
+
+
[0043] Please refer to FIG. 1 , which shows the ability of various strains to decompose the rice straw of Japonica Rice. The Japonica rice straws treated with shaking culturing for a week are classified, dried and weighted. The decomposition percentage of rice straws treated with different microorganisms is calculated by the following formula.
[0000]
Decomposition
%
=
(
Total
dry
weight
of
fermentative
rice
straws
-
Dry
weight
of
intact
rice
straws
)
(
Total
dry
weight
of
fermentative
rice
straws
)
×
100
[0044] As shown in FIG. 1 , the PMBIII strain group has the best decomposition ability than the others. The decomposition percentage of rice straws is about 10.38%. The PMBIII consists of Bacillus licheniformis (PMBP-m5) (Patent Deposit Designation: PTA-5824, deposited on Feb. 18, 2004 with the American Type Culture Center, Manassas, Va. 20110-2209, USA), B. subtilis (PMBP-m6) (Patent Deposit Designation: PTA-5818, deposited on Feb. 13, 2004 with the American Type Culture Center, Manassas, Va. 20110-2209, USA), and B. amyloloquefaciens (PMBP-m7) (Patent Deposit Designation: PTA-5819, deposited on Feb. 13, 2004 with the American Type Culture Center, Manassas, Va. 20110-2209, USA).
[0045] (C) The preparation of culture solution:
[0046] An LBY (Lactose Beef extract Yeast extract, LBY) culture medium containing 0.25% (w/v) lactose, 0.2% (w/v) beef extract and 0.05% (w/v) Yeast extract is prepared. The pretreated waste rice straws are added into the LBY culture solution by a ratio of 5% (w/v) respectively. The microorganism suspensions of the PMBPIII strain group are added into the LBY medium at the concentration of 1×10 6 cfu/ml. And then, the culture solutions are prepared. The PMBPIII strain group consists of Bacillus licheniformis (PMBP-m5), B. subtilis (PMBP-m6) and B. amyloloquefaciens (PMBP-m7) isolated from the waste rice straws or livestock excrements and are Gram-positive bacteria.
[0047] (D) Fermentation culturing under continuously shaking:
[0048] The culture solutions are incubated at 50° C. and shaked at 200 rpm for a week. And then a biopulp of the waste rice straws are prepared. Each treatment has duplicate treatment.
[0049] (E) Filtrating the biopulp of the waste rice straws:
[0050] The biopulp of each treatment is screened by a sieve with 270 meshes for preparing a filtrate. The lower part of the filtrate is used for preparing the pulp fiber for papermaking. The upper part of the filtrate is recovered to formulate the plant nutrition.
[0051] (F) The dilution of the filtrate for formulating a plant nutrition solution:
[0052] The recovery filtrate is diluted with sterile water by a volume of 50 times for preparing a plant nutrition solution.
[0053] (G) The application of the plant nutrition solution to the crop cultivation:
[0054] The lettuce seeds are immersed in the plant nutrition solution for 2 days and then planted in 5-inch-diameter pots. And then each time 100 ml of plant nutrition solution is applied to each treatment per week respectively. The effects of the plant nutrition of each treatment on the growth of the lettuce seedlings are examined after four weeks.
[0055] Additionally, serial dilutions of 10, 25, 50 and 100 times of the recovery filtrates are prepared. The diluted filtrates are applied to the germinated cucumber seeds one time per week for three times. The growths of the cucumber seedlings are examined after 21 days.
[0056] (H) The improvement of the plant nutrition solution:
[0057] 0.3% (w/v) seaweed powder (a kind of polymer), 0.1% (w/v) urea, 1% (v/v) alcohol, and 2% (v/v) Hoagland's solution (The Hoagland's solution contains 0.6 g copper sulfate, 0.11 g ferric sulfate, 0.79 g manganese chloride and 0.15 g zinc sulfate per liter.) are added into the foregoing recovery filtrate of waste rice straw for formulating the RSL plant nutrition solution. The seaweed powder is a kind of polymer. The other kinds of polymer can be used, for example, alginic acid, an alginic salt and polyelectrolytes, etc. Also, the corn wheat bran or starch can be used to replace the polymer.
[0058] (I) The application of the RSL plant nutrition solution to the crop cultivation:
[0059] Serial dilutions of 250, 500, 750 and 1000 times of the RSL plant nutrition solution are prepared. The diluted RSL plant nutrition solution is applied to the germinated cucumber seeds one time per week for three times. The growths of the cucumber seedlings are examined after 21 days.
[0060] The effects of the plant nutrition solutions formulated from different treatments of waste rice straws on the plant growths are described as follows. Please refer to FIG. 2 , which shows the effects of the biopulp filtrates at 50-fold dilution on the germination of lettuce seeds according to a preferred embodiment of the present invention. The germination percentages of different treatments are between 97% and 100%. The germinations of the lettuce seeds are not inhibited or harmed by the plant nutrition solutions. The roots of the lettuce seedlings are not unusual and the root hairs grow vigorously.
[0061] Please refer to FIG. 3 , which shows the effects of the biopulp filtrates at 50-fold dilution on the growth of lettuce according to a preferred embodiment of the present invention. The filtrates of different pretreated waste rice straws do not affect the plant heights and fresh weights of lettuce seedlings. The filtrate obtained from the of waste rice straws treated by boiled treatment has the effect of enhancing the growths of lettuce seedlings, especially, the filtrate obtained from the Indica rice ( FIG. 4 ).
[0062] According to another preferred embodiment, the PMBPIII strain group consists of Bacillus licheniformis (PMBP-m5), B. subtilis (PMBP-m6) and B. amyloloquefaciens (PMBP-m7) are inoculated into the LBY culture medium containing 5% (w/v) waste rice straws. The waste rice straws of an Indica rice ( Oryza sativa L. subsp. indica) are provided. The variety of the Indica rice is Taichung Sheng No. 10. The rice straws are sun-dried, cut into small segments of 2-3 cm length. The inoculation concentration of the PMBPIII strain group is 1×10 6 cfu/ml. The culture solutions are incubated and fermented at 50° C. and shaked at 200 rpm for four days. And then, 1% (w/v) CaO is added into the solution. The solution is heated up to 140° C. for 30 minutes for preparing a biopulp solution. The biopulp solution is screened by a sieve with 270 meshes for preparing a biopulp filtrate. The biopulp filtrate is diluted with sterile water for serial dilutions of 10, 25, 50 and 100 times. The diluted filtrates are applied to the germinated cucumber seeds one time per week for three times. The growths of the cucumber seedlings are examined after 21 days. The growths of the lettuce seedlings are not inhibited or harmed by the plant nutrition solutions. The plant nutrition solutions have somewhat effects on enhancing the seedling developments and mitigating the disease of powdery mildew. Please refer to FIG. 5 , which shows the effects of the biopulp filtrates of different dilution folds on the growths of cucumber seedlings according to a preferred embodiment of the present invention. The fresh weights of the cucumber seedlings treated with the plant nutrition solutions formulated from the biopulp filtrate are better than that of the control. The roots grow well. And the plant nutrition treatment can help the plants to stand erectly.
[0063] According to another preferred embodiment, the filtrate produced by the biopulp of waste rice straws can be improved by adding some additives. Four additives including 0.3% (w/v) seaweed powder, 0.1% (w/v) urea, 1% (v/v) alcohol and 2% (v/v) Hoagland's solution are added into the recovery filtrate of the biopulp of waste rice straws for formulating a RSL plant nutrition solution. The Hoagland's solution contains 0.6 g copper sulfate, 0.11 g ferric sulfate, 0.79 g manganese chloride and 0.15 g zinc sulfate per liter. The RSL plant nutrition is diluted with the sterile water for making serial dilutions of 250, 500, 750 and 1000 times. The different diluted plant nutrition solutions are respectively applied to the germinated cucumber seeds one time per week. The growths of cucumber seedlings are examined after 21 days.
[0064] Please refer to FIG. 6 and FIG. 7 . FIG. 6 shows the effects of different RSL plant nutrition concentrations on the growth of cucumber seedlings according to a preferred embodiment of the present invention. The results reveal that the growths of cucumber seedlings are enhanced by the RSL plant nutrition solutions. The effects on the growths of cucumber seedlings of RSL plant nutrition solutions are better than those of the control I (plant nutrition directly formulated from the biopulp filtrate) and the control II (water treatment). FIG. 7 shows the information about the growth of cucumber seedlings after being treated with RSL plant nutrition three times according to a preferred embodiment of the present invention. The fresh weights of the cucumber seedlings are better than the other treatments. The whole plants and leaves are taller and larger and the disease of powdery mildew is mitigated for the cucumber.
[0065] While the invention has been described in terms of what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention needs not be limited to the disclosed embodiment. On the contrary, it is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims which are to be accorded with the broadest interpretation so as to encompass all such modifications and similar structures. | The present invention relates to a plant nutrition formulation and method thereof, and more particularly to a plant nutrition formulated by recovery filtrate from non-woody fiber plant biopulping and method thereof. The present invention provides a plant nutrition formulation including steps of providing a culture solution containing a culture medium, a non-woody fiber plant material and microbial suspension, fermenting the culture solution for preparing a biopulping solution, filtrating the biopulping solution for preparing a filtrate, and formulating the filtrate for preparing a plant nutrition. | 2 |
The U.S. Government has rights in this invention described and claimed herein pursuant to Contract No. N00014-77-C-0412.
This invention is directed generally to the field of acoustic microscopy and more particularly to a method and apparatus for imaging of objects utilizing acoustic waves wherein the transducer, the sample, and the pulse coupling apparatus are cooled to very low temperatures.
Acoustic microscopes have become quite well known as a means of very high resolution microscopy since their disclosure in the Feb. 15, 1974 of Applied Physics Letters in an article entitled: "Acoustic Microscope, Scanning Version" at pages 163ff and authored by Lemons and Quate, or as further disclosed in U.S. Pat. No. 4,012,950 to Kompfner, Chodorow, and Lemons both incorporated by reference. Generally speaking, acoustic imaging involves as a first step the generation of one or more radio frequency signals typically in the microwave frequency region. The signals are delivered to an electric transducer which generates bulk acoustic waves of short wave length in the form of a collimated beam in an acoustic propogating medium. Each acoustic beam is then delivered to an acoustic lens which effects a sharp convergence of the beam to a focal point where the object to be imaged is positioned. A non-linear action of the impinging acoustic energy occurs either within the object itself or in the adjacent medium so as to generate frequencies which are different from those applied or to change the amplitude of the applied frequency. This reflected output acoustic energy is subsequently detected, converted into an electric signal, and delivered to an oscilloscope or other mechanism for displaying the optical image of the object can be displayed. However, the resolution of the acoustic microscope is presently limited by the sound wavelength and the coupling fluid between the lens and the sample.
It is therefore an object of the present invention to provide an improved acoustic microscope capable of operating at much higher frequencies and thus shorter wave lengths then previously used.
It has been found that the use of cryogenic fluids as a medium to cool the transducer and object offers two advantages over room temperature fluids for use in acoustic microscopy: low sound speed, and low acoustic attenuation. Liquid Nitrogen, Argon, and Helium have all been used. However, liquid helium emerges as the ultimate fluid for high resolution acoustic microscopy because of its near zero acoustic attenuation at very low temperatures.
It is an objective of the present invention to optimize the frequency capability of an acoustic microscope using cryogenic fluids to cool the lens and sample.
In a book entitled ACOUSTIC IMAGING, volume 12, edited by Eric A. Ash and C. R. Hill and published by Planham publishing Corporation in 1982 article by D. Rugar, J. S. Foster, and J, Heiserman entitled ACOUSTIC MICROSCOPY AT TEMPERATURES LESS THAN 0.2° K., incorporated herein by reference, a disclosure is made of an acoustic microscope scanner and appropriate cryogenic fluids to achieve an microscope operating frequency of up to 2.6 GHz. However, as the frequency of the microscope is increased to these gigahertz levels, a fundamental problem intervenes of limiting the signal to noise ratio of the instrument.
It is an objective of the present invention to achieve operating frequencies of a helium acoustic microscope of at least 4.2 GHz and it is a further objective to extend the operating frequency of the microscope to 8 GHz, thereby obtaining a lateral resolution of 200 A with acceptable signal to noise ratio levels.
BRIEF SUMMARY OF THE INVENTION
The signal to noise problem in the present invention is reduced by an adaptation of a low noise amplifier previously disclosed by S. Weinreb IEEE Transactions Microwave Theory Tech. 28, 1041 (1980) in which an FET amplifier for use in astronomy is disclosed operating at temperatures as low as 20° k. In the present invention, the operating temperature of this amplifier is reduced even lower, and the amplifier is coupled to the output circuit from the acoustic transducer of the acoustic microscope. To further enhance the signal to noise ratio and maintain the input power of the system a know pulse compression technique is used to generate a high frequency pulse train which is impressed on the basic operating frequency (at least 4.2 GHz, up to 8 GHz) by using room temperature components. This pulse train is passed on a wire close to a super cooled transmission line which serves a directional coupler between the low noise amplifier and the transducer. By use of this super cooled transmission line, extremely low losses in the input pulse frequency which drives the transducer are achieved; further, the output frequency from the transducer to the amplifier are coupled over this same super cooled transmission line to minimize losses and optimize the signal to noise ratio.
In a further improvement over known low temperature acoustic microscopes, a transducer has been designed to give maximum conversion efficiency between the electric and acoustic powers with reasonably uniform distribution of the acoustic field over the lens aperture and minimum amount of power loss due to sound waves falling outside the lens.
In known acoustic transducers, the radius of the transducer is usually two to three times the radius of the lens aperture. In the transducer according to the present invention, the radius of the transducer is approximately the same size as the aperture, or about 125 micrometers. Surprisingly, it has been discovered that this size of transducer is the most efficient in receiving the field from the lens aperture at these extremely high frequencies. The field is generated using a top electrode on the top surface of the transducer. It has been found that the thickness of this top layer electrode is also critical to the efficiency of the system again, surprisingly, it has been found that a 2000 A (half wave) thick electrode provides the optimum conversion efficiency at frequencies of at least 4 GHz and as high as 8 GHz.
Yet another limitation on known low temperature acoustic microscopes, is that effective imaging only occurs on the top surface of the specimen. It is therefore an object of the present invention to provide a means for effectively imaging below the surface of the object.
This objective is achieved by heating the cryogenically cooled object while imaging is occurring. In the preferred embodiment, heating is applied to a surface of the object which is opposite to the surface being imaged. Alternatively, the object may be self heated by turning on an integrated circuit. In either case, the radiated heat turns to sound waves when it passes out of the object into the cryogenic fluid to effectively modulate the incoming acoustic wave; since at these temperatures any voids below the surface function effectively are a vacuum, the heat or sound waves are effectively modified by the presence of such voids and thus become apparent on analysis of the reflected radiation. The heat or sound waves are also effectively modified by material defects and changes below the surface.
The above objective of the invention and the manner in which they are achieved will be more readily understood by reference to the following detailed description with reference to a specific embodiment of the invention shown in the accompanying drawings wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic showing both the room temperature circuitry and the super cooled circuitry and transducer and sample which make up the acoustic microscope of the present invention;
FIG. 2 is a cross-sectional view of a transducer which is especially useful with the present invention; and
FIG. 3 is a graph showing the variation of transducer radiation resistance as a function of frequency for different top electrode thickness which may be utilized to optimize selection of a transducer.
DETAILED DESCRIPTION
The mechanically scanned acoustic microscope 2 shown in FIG. 1 utilizes a fluid cryogenic medium to couple sound from the acoustic lens 4 to a reflecting sample 6. The sound waves from the acoustic lens are generated using the room temperature electronics shown in general in FIG. 1. The signals generated which preferably are at least over 4 Ghz and preferably 8 Ghz, are coupled through a matching network 8 to the lens through a super conducting directional coupler 10. The coupler 10 together with the low noise amplifier 12 for amplifying the output signals are cooled to extremely low temperatures. In this manner, by cooling the lens and sample to less than 0.2° K. and preferably to 0.1° K., and by cooling the amplifier and directional coupler to no more than about 4.2° k., the microscope can effectively operate in the reflection mode at above 4.2 GHz and has a demonstrative effectiveness at a preferred frequency of 8 GHz.
In a preferred embodiment, the microscope is cooled by an HE3-HE4 dilution refrigerator. The acoustic lens 4 is mounted on a mechanical positioner which translates the lens in a raster pattern to form the image as disclosed in detail in the incorporated portion of the book ACOUSTICAL IMAGING.
The lens itself is of a special design to give maximum conversion efficiency between electrical and acoustic powers with a reasonably uniform distribution of the acoustic field over the lens aperture 16 with a minimum amount of power loss due to sound waves falling outside the lens. The transducer used in the present invention is especially useful at frequencies in the realm of 8 GHz. In known transducers for acoustic imaging, the transducer radius is usually two to three times the radius of the lens aperture as a trade off between these factors. The radius of the transducer 20 here is chosen to be approximately the same size as the aperture 16 or about 125 micrometers. Thus the acoustic field distribution on the lens surface due to these transducers is not relatively uniform; but a larger size transducer which would give a more uniform illumination cannot be used because it becomes quite inefficient as the size is increased.
At frequencies around 8 GHz, the two critical transducer parameters which determine the conversion efficiency and band width are the thickness of the gold top electrode 22, and the radius of the transducer 20. A cross section of typical transducer is shown in FIG. 2; the variation of transducer radiation resistance as a function of frequency for different top electrode thicknesses is shown in FIG. 3. FIG. 3 thus clearly demonstrates the effectiveness for an 8 Gigahertz system of a 2000 angstrom thick electrode. In a design of the transducer it has to be taken into account that the top electrode 22 effectively loads the transducer and changes the resonant frequency. To minimize the effect of the loading, one would like the electrode thickness to be either very thin with respect to an acoustic wave length or some multiple of the half wave length. Gold has a sound velocity of 3.21 Km/s and hence the 500 to 1000 A thick top electrodes usually used in low frequency application would be 1/8 to 1/4 wave thick at 8 GHz. Making the top electrode significantly thinner than 500 A becomes impractical because of the increased resistive loss with a thinner film. FIG. 3 thus demonstrates that a 2000 A (half wave) thick electrode should be used to get the optimum conversion efficiency at 8 GHz even though the acoustic band width is small due to the acoustic resonance in the top electrode.
It has also been calculated that 125 micrometer or larger transducers give very small radiation resistance and reactance as compared to larger ones. The finally consideration in the design is that the transducer must be large enough to illuminate the lens aperture 16 but not be to large which results in reduced efficiency. It was through these considerations that the design of the transducer especially useful at higher frequencies than 4 GHz and specifically at 8 GHz was evolved.
Also crucial to the noise performance of the microscope is the system 14 which amplifies and detects the microwave signals from the acoustic transducer. A superconducting coaxial transmission line 10 which also functions as a directional coupler connects the transducer 4 to a two stage low noise gallium arsenide field effect transistor pre amplifier which is located in the same 4.2 K. helium bath of the refrigerator. By locating this coaxial transmission line in the same 4.2° K. environment, an extremely low loss coupler is achieved which is capable of transferring the detected signal from the lens to the amplifier 12.
The receiving system band width, determined by a room temperature intermediate frequency amplifier shown in the remainder of FIG. 1 and to be described below is 20 Mhz. The transmitted RF pulses are generated by room temperature components, and are coupled into the coaxial line leading to the transducer by a directional coupler 30 also located within the low temperature environment. Specifically, a 20 Mhz generator combined with a local oscillator having a 7.8 GHz output provides an 8 GHz signal runs through a wire which is placed closely adjacent the low loss transmission line 10. In this manner, the microwave signals for driving the lens are inductively coupled into the transmission line. By using such coupling, room temperature thermal noise from the transmitting system does not degrade the noise performance of the receiving system.
Turning now to the room temperature electronics of FIG. 1, these generate and receive the RF level signal which effectively determines the system band width. Specifically, a short pulse generator 40 generates a relatively short pulse as shown of about 1 nanosecond duration. This is filtered in filter 42 and passed to the dispersive filter 44. The dispersive filter which is of a type already known in the art, takes the short pulse and turns it into a longer duration pulse which is effectively frequency coded as a function of time. It should be noted that the two dispersive filters 44A in the frequency generator and 44B in the frequency receiver, are effectively mirror images of each other in the sense that the dispersive filter in the frequency receiver portion will recognize the coding applied by the dispersive filter in the transmitting section. The 200 megahertz signal is mixed with a local oscillator output 46, to provide the desired 8 GHz transmission frequency. This signal is then again amplified and attenuated as necessary at 48. The duration of the 8 GHz signal to be used to drive the acoustic transducer is defined by the time gate 50 so that for example if the transducer is to be driven for a period of 4 microseconds, then a space of 4 microseconds for the receipt of the reflections is provided by the master pulse driver 52. This pulse driver also drives the original short pulse generator, and a time gate in the signal output lines 54 as well as a sample and hold device 56 for capturing the information content of the reflected signals from the transducer. The 8 GHz signal is then passed through a band pass filter 60 to screen out any signals which are not at or very close to the desired 8 GHz frequency. The output of the band pass filter is then coupled as previously described in the super cooled section to the low loss directional coupler 10 to be transferred to the matching network and the transducer. The 50 ohm resistor is provided as a termination on the wire carrying the 8 GHz signal to match it with the resistance in the line coupling it to the transducer, as well as to prevent unnecessary reflections of the 8 GHz signal.
The 8 GHz signal is now transferred to the lens which is excited and launches the plane waves to the substrate 6; reflections are received at the lens and pass through the superconducting coaxial line 10 to the super cooled low noise amplifier. Because the superconducting coaxial transmission line functions to carry the signals to the transducer and the reflected signals which contain the actual information content about the surface of the object 6 back to the low noise amplifier, its design is critical to the effective performance of this system.
The reflections from the sample are passed through band pass filter 70, through timing gate 54 and mixed at local oscillator 72 to provide a difference signal which is once again 200 MHZ. The dispersive filter can now effectively decode the long pulse and convert it back to a short pulse shown as of about 20 nanoseconds, which effectively contains the information content of the signal. The use of this coding technique allows the system to use a pulse of small amplitude and long duration in the transmitting system and convert it to a high amplitude short duration pulse in the receiving system; this is important since the system is limited on the input power which can be used to drive the transducer.
The output of the dispersive filter is attenuated as desired, amplified and stored for display on a video display to build up a complete picture of the surface of the sample as the microscope is scanned across the surface.
The use of the bidirectional coupler is a significant change from the three port circulator most commonly used in such applications. In such a device, the input is applied to one of three possible ports, and circulates to the next port where it is transmitted out to drive the transducer; the return reflections are received at the same circulator port and again circulate in the same direction as the input pulses to the next or third port where they are applied to appropriate decoding circuitry. Such circulators do not work effectively at extremely low temperatures such as must necessarily be used on the input to the low noise super cooled amplifier.
In a further advantageous modification of the present invention, it has been found that by heating the sample under inspection, information under the surface can be detected, even in this cryogenic atmosphere. It is known that in such cryogenic detection systems, the reflections all occur directly from the surface of the object i.e. there is little or no sub-surface penetration nor is it possible to focus the lens at a point below the surface to inspect under the surface. All experiments to date have demonstrated that reflections off the sample surface 6 is effectively perfect in this cryogenic situation. It has been found that by putting a heater 80 on the back side of the object under examination, that in fact the sound waves pass through the device and emerge from the surface as sound waves which modulate the incoming acoustic waves. The same effect occurs if the device itself is heated, as for example by turning on a integrated circuit. Heat waves at these temperatures are just incoherent sound, as opposed to the coherent sound waves which emerge from the aperture 16 of the transducer. Thus as the sound waves travel through the crystal, if they come to a defect as for example a hole or divot or defect in the device, their path of travel is blocked, since at these temperatures, such an opening or defect will scatter the incoherent sound waves. Thus while sound waves coming toward the aperture will be detected in all solid areas of the sample, if internal holes exist, for example, travel of the sound waves will be blocked and no sound waves will emerge from the top surface of the device under examination. Since the incoming sound waves from the heat source and the coherent waves from the transducer meet above the surface 6 under inspection, they effectively scatter off each other, reducing the strength of the signal which will be reflected back and detected in the acoustic microscope system. The net effect is a scattering of the acoustic phonons which make up the coherent planar sound waves transmitted by the transducer 4; they are scattered by the heater phonons which emerge from the surface 6 under inspection. The fact that the heater waves will emerge from the surface is a result of what is known as the KAPITZA anomaly. The anomaly states that high frequency sound does pass through the surfaces, and it has been determined that such high frequency sound is easily developed with a heater 80.
Other modifications or alternative embodiments of the present invention may become apparent to one of skill in the art who has reviewed the above disclosure. Therefore, the scope of the present invention is not to be limited to the preferred embodiment which is described above, but only by the claims which follow. | A method and apparatus for imaging objects utilizing acoustic waves at frequencies above 4.2 Ghz and up to 8 Ghz wherein the transducer and the object imaged by waves or beams from the transducer are both at a temperature no greater 0.2° K. The transducer is driven by pulses generated by a short pulse generator which are stretched and coded by a dispersive filter and inductively coupled to a low temperature coupler to be use to drive the transducer. The frequency returns are carried by the same bidirectional coupler to a low noise amplifier. Both the low noise amplifier and bidirectional coupler are maintained at a temperature of less than 4.2° K. The output of the amplifier is then coupled to a dispersive filter which responds the coding in the first dispersive filter to decode the information and reconstruct the signal. Subsurface defects are detected by heating the object while it is inspected by the acoustic transducer. | 8 |
RELATED CASE
This application is a continuation-in-part of U.S. patent application Ser. No. 08/302,121, filed Sep. 7, 1994, (now abandoned) which is a continuation-in-part of original application, Ser. No. 08/079,341, filed Jun. 18, 1993 (now abandoned).
BACKGROUND OF THE INVENTION
The invention relates to a protective surgical drape construction for an operation microscope wherein an optically clear protective window is provided for the objective lens of the microscope.
Objective-lens protection has been a feature of protective surgical drapes for operation microscopes. Generally, such constructions take the form of a flanged annular body wherein the flange is sealed to the border of a local circular opening in the drape material and wherein the annular body is adapted for telescoping removable attachment to the objective-lens barrel or mount of the microscope. The annular body is axially short and provides mounting for a flat lens-protecting optically transparent element, which may be of glass or a suitable plastic, mounted perpendicular to the optical axis of the objective. Modern surgical microscopes of the character indicated incorporate sophisticated mountings with six dimensions of manipulated orientation of the objective, namely, three orthogonal axes of rotatable adjustment, and three orthogonal axes of rectilineal displacement, and for certain situations of adjusted orientation in relation to relatively fixed illumination, internal reflection between the objective lens and the flat protective transparent element can be a source of degraded viewing through the microscope.
BRIEF STATEMENT OF THE INVENTION
It is an object of the invention to provide an improved surgical drape of the character indicated.
A specific object is to meet the above object with a construction which inherently reduces the chances of degraded viewing through a drape-protected binocular microscope having stereoscopic-viewing capability.
Another specific object is to meet the above objects for the case of a microscope having provision for an internal source of projected field illumination.
A general object is to meet the above objects with a simple construction minimally affecting manufacturing cost, and requiring little or no additional skills for operational use.
The invention in a preferred embodiment meets these objects in a surgical drape construction wherein a tubular body, peripherally sealed to a local lens aperture in a drape, is adapted for removable concentric engagement to the exposed end of the objective-lens barrel of a microscope having spaced oculars for stereoscopic viewing through a single objective lens, wherein the tubular body mounts a flat optically transparent element which closes the body, and wherein the flat transparent element is fixedly so inclined that a geometric normal to the flat transparent element is at an acute angle to the axis of concentric engagement, i.e., to the optical axis of the objective lens. Would-be reflections are thereby deflected off-axis essentially in the same direction, for each of the viewing axes via the objective lens, and microscope viewing is materially enhanced for all subject-matter aspects with respect to the incident light.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described in detail for several embodiments, all in conjunction with the accompanying drawings, in which:
FIG. 1 is a simplified view in perspective of the viewing head of an operation microscope having stereoscopic viewing capability, the same being schematically shown in the course of assembly with a protective surgical drape of the invention;
FIG. 2 is an enlarged view in side elevation of a local objective-lens fitment feature of the drape of FIG. 1, parts being broken-away and in longitudinal section;
FIG. 3 is a plan view of an optically clear protective element of the drape fitting of FIG. 2, with illustrative schematic indication of various axis intercepts with this flat element;
FIG. 4 is a view similar to FIG. 2, for a first modification; and
FIG. 5 is an exploded view, otherwise similar to Figs. 2 and 4, for a second modification.
DETAILED DESCRIPTION
Referring initially to FIGS. 1 to 3, the invention is shown generally by a protective drape 10 for shielding protection of an operation microscope, shown as a microscope head 11 with upper supporting structure which may include a floor stand, or a wall or ceiling suspension (not shown) and various articulating and displaceable elements that culminate in a support bracket 12. The microscope 11 is shown to include binocular-viewing oculars 13, 13' for stereoscopic viewing, with means 14 for selectively accommodating ocular spacing to user convenience.
The oculars 13, 13' are respectively associated with separate viewing axes which establish a geometric plane of viewing passage through a single objective lens having a lens barrel 18 concentric with the central axis 20 of the objective lens. In FIG. 2, this geometric plane is also indicated by the line 20.
The drape 10 includes a fitment 15 of the invention, having a radially outward flange 16 in peripherally sealed relation to the margin of a viewing opening in the material of the drape; and the bore 17 of fitment 15 is sized for concentric telescopic assembly to and removal from the exposed end of the barrel 18 of the single objective lens of microscope 11.
The fitment 15 is seen in FIG. 2 to be an annular molded-plastic part which has a cylindrical body wherein the bore 17 has one or more angularly spaced longitudinal ribs 19 for frictionally stressed retention to the lens barrel 18, concentric assembly being schematically suggested by designation in FIG. 2 of the central axis 20 of the objective lens of the microscope. The cylindrical body is truncated at an inclination which conforms to the slope of an annular seat or shoulder formation 21 in the bore 17. This shoulder formation 21 is adapted for removably seated positioning of a flat optically transparent element 22 which in FIG. 3 is seen to be circular. Coacting lug (23) and slot (24) formations at equal angular spacings enable bayonet-locking engagement and retention of transparent element 22 to its seating shoulder 21, upon axial registry of lugs 23 with slots 24, followed by incremental rotation out of such registry, as by finger-torquing of one or another of exposed lugs 25 which are integral formations of transparent element 22. The torqued rotary displacement of element 22 to the location at which lugs 25 abut lugs 23 (as seen in FIG. 2) will determine the angular location at which lugs 23 register with slots 24, namely, the angular location at which axial reception and removal of element 22 is possible, as when, in the course of a surgical operation, blood or other debris may clutter an optically used area of element 22; such a situation is rapidly resolved by removal of the thus-soiled element 22 and its replacement by a clean duplicate element 22.
FIG. 3 is additionally useful for a discussion of various axis intercepts (and thus axial spacings) at passage through or reflection from the flat optically transparent element 22. The ocular-viewing axis intercepts 13, 13' are shown at spacing a in a geometric plane of objective lens passage which may contain the central axis 20 of the objective lens, but which in FIG. 3 is shown at short offset b from axis 20. The microscope of FIG. 1 will be understood to be equipped with an internal source of field illumination wherein illumination is externally projected on an axis 28 which in FIG. 3 is shown with intercept at transparent element 22, the intercept of axis 28 being at opposite offset (c) from the central objective lens axis 20. Adjustable means will be understood to be part of the microscope whereby the offset (c) of the projection axis 28 for field illumination may be selected for optimal field illumination and viewing; preferably, although not necessarily, such adjustability is with symmetry in respect of the spaced viewing axes of oculars 13, 13', and a greater adjusted offset c' is shown at 28' for the axis of externally projected illumination.
FIG. 4 illustrates extreme simplicity of the invention in an embodiment in which the entire fitment 15' is the product of a single molding (e.g., injection-molding) operation, using a single plastic material, such as methylmethacrilate, which will provide a flat optically clear element 22' that is integrally united to the bore 17' and at an inclination which is consistent with the truncation. The sealed assembly of flange 16' to an aperture in drape 10, and friction-rib (19') engagement to the objective-lens barrel 18, are as described for the embodiment of FIGS. 2 and 3.
In the embodiment of FIG. 5, a simple flanged annular body 50, with a cylindrical bore 51 and one or more friction ribs 52, lends itself to flange-bonding to the rim of a circular viewing opening in the material of drape 10 (not shown in FIG. 5, but suggested schematically by an upper arrow A). The body 50 is shown with one or more external friction ribs 53 for retention of a telescopic fit of body 50 to the cylindrical bore 54 of a second (and reusable) part 55 of the embodiment of FIG. 5. When part 50 is preassembled and sealed to drape 10, as suggested at A, part 50 may be of molded plastic and discarded with the drape, after single-patient use. On the other hand, part 55 is not necessarily to be discarded and may be autoclavable, thus of precision-molded or machined stainless-steel construction. More particularly, the part 55 is shown to be formed with an annular shoulder 56 for oriented peripheral support of a flat glass element 57, preferably of optical quality, and this support is retained by a ring member 58 in threaded engagement with a counterbore that is concentric with shoulder 56.
In an alternative employment of structure described in connection with FIG. 5, the flange of body 50 is not bonded in preassembly to the drape material. Instead, the viewing aperture of the drape will be understood to have a coated annulus of pressure-sensitive adhesive, concentric with the opening and designed for registry with the flange of body 50, whether applied to the upper level suggested at A or pulled over the cylindrical remainder of body 50, as suggested by introduction at a lower level B, with adhesive coating facing the underside of the flange of body 50. Thereafter, upon telescopically assembling part 55 to part 50, to the point of adjacency to the flange of body 50, the assembly and peripherally sealed relation to the drape are assured.
It will be seen that the described embodiments of the invention meet stated objects and offer different features of convenience and utility for various operation usages of microscope 11. In all cases, the flat optically transparent plate is inclined to the optical axis of the objective lens of the microscope. This inclination may be stated to be an acute-angle relationship α between a normal 60 to the flat transparent member, with respect to the objective-lens axis 20, where the acute angle α is suitably in the range 10° to 30°, and is preferably about 15°.
Stated in other words, for the preferred embodiment wherein the two spaced oculars 13, 13' achieve stereoscopic viewing, via separate spaced viewing axes through the single objective lens, a geometric plane of viewing passage through the objective lens is established by the respective ocular-viewing axes. This geometric plane may include, or be at one direction of offset from, the central optical axis of the objective lens. The plane of transparent element 22 may thus be viewed as having been tilted about an axis which is either substantially normal to, or is otherwise in a second geometric plane that is substantially normal to, the central axis 20 of the objective lens. And the tilt angle α is particularly useful in enabling transparent element 22 to deflect internal reflection of projected illumination (e.g., at axis intercepts 28 or 28') away from degrading influence on the quality of microscope viewing, while also performing a similar function for extraneous light sources externally to the microscope.
This preferred orientation of the transparent element 22 can be ensured by providing a marker 62 on the fitting 15 and by providing a corresponding marker 61 on the microscope 11 on or near the lens barrel as shown in FIG. 1. When these markers 61 and 62 register, the transparent element 22 is in its advantageous orientation.
As can be further seen in FIG. 1 the two spaced oculars 13 and 13' for stereoscopic viewing already impose a certain orientation of the drape 10 because the drape 10 has to accommodate the two oculars 13 and 13', as is schematically depicted by line segments 63 and 64. Because the fitting is preferably a preassembled part of the drape 10, this circumstance automatically leads to a pre-orientation of the transparent element 22, wherein the pre-orientation is at least an approximation of the preferred orientation.
In an especially advantageous orientation of the transparent element 22, the geometric normal to the flat transparent element 22 is parallel to or lies in a plane defined by the central axis 20 of the objective lens and by the illumination axes, whose intercept 28 with the flat transparent element 22 can be seen in FIG. 3. This very special orientation of the flat transparent element 22, or 57, in the case of the embodiment of FIG. 5, ensures that reflections from the field illumination are not biased toward a single one of the ocular viewing axes because, with this special orientation, the inclination of the flat transparent element 22 is symmetrical to both ocular-viewing axes, as viewed from the illumination axis.
With respect to the embodiment of FIG. 5, it is observed that the part 55 having the transparent plate 57 enables assembly of plate 57 to the body 50 at any selected angle of rotation about the central axis of the objective lens, whereby to set the angle α for minimum cross-light exposure to an ambient source which might otherwise affect the clarity of microscope viewing. And having thus selected the angle of rotation about the central axis of the objective lens, the selected angle serves both of the ocular-viewing axes with substantially equal effectiveness. There may of course be a marker 59 cooperating with marker 61 on the microscope 11 and corresponding to a desired preselected angle of rotation.
The embodiments of FIGS. 2 and 5 are recognizably useful for microscope applications wherein laser radiation utilizes microscope optics, the transparent elements 22, 57 being removable for such usage.
From the foregoing description and the drawings, the invention will be seen to provide drape structure which has the inherent capability of correctly orienting the transparent element 22 with respect to the ocular-viewing axes and the illumination axis of projected field illumination, all for the case of a stereopticaly binocular viewing system having convergent viewing axes through a single objective lens, wherein one end of the barrel of the objective lens is externally exposed. The viewing axes establish a first geometric plane through said objective lens, and the illumination axis and the central axis of the objective lens establish a second geometric plane through the objective lens wherein the second geometric plane is perpendicular to the first geometric plane and bisects the convergence of the viewing axes. The drape is an elongate bag-like protective device forming an envelope of pliant plastic material which has an upper open end adapted to receive the microscope and which is adapted to be closed for completion of bag-enclosure of the microscope, and the drape having a formed localized lower region of the lens-barrel engageability. The formed lower region comprises a tubular body peripherally assembled to the pliant plastic material at a local lower-end opening in the envelope, and the tubular body has a flat optically transparent element peripherally closing the tubular body. The flat optically transparent element is acutely inclined to the viewing and illumination axes at passage of these axes through the optically transparent material. The envelope has a lateral-side opening facing in one direction of offset away from the elongate direction of the envelope and is removably adapted for protective closure of said lateral-side opening around the viewing oculars. The direction of acute-angle inclination of the flat optically transparent element is symmetrical with respect to the said direction of offset of the lateral-side opening, whereby upon assembly of the drape to the microscope, the inclination of the flat optically transparent element substantially symmetrically accommodates the viewing axes to the illumination axis. For greater precision, a local angular indicium mark on the lens barrel is in angular register with a local angular indicium mark on the tubular body when the inclination of the flat optically transparent element precisely symmetrically accommodates the viewing axes to the illumination axis. | A surgical drape construction wherein a tubular body, peripherally assembled to a local lens aperture in a drape, is adapted for removable concentric engagement to the exposed end of the objective-lens barrel of a microscope, wherein the tubular body mounts a flat optically transparent element which closes the body, and wherein the flat transparent element is fixedly so inclined that a geometric normal to the flat transparent element is at an acute angle to the axis of concentric engagement. Would-be reflections are thereby deflected off-axis, and microscope viewing is materially enhanced for all subject-matter aspects with respect to incident light. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
In an optical system an optical element may need to be rotated about an axis and require one or two other axes for alignment. The present invention is a device and method for providing such alignment by gimbaling the axis of rotation of the optical element.
2. Description of the Prior Art
Typically in the prior art, an optical element required to rotate about one axis and be adjustable for alignment purposes about the other one or two axes is held in a mount which is coupled directly to the rotational axis. The optical element is aligned about the other one or two axes relative to this mount. That is, in the prior art the axis of rotation is fixed and the optical element is moved by its mount relative to the axis of rotation.
This prior art approach is satisfactory for some systems. However, in other systems it is important for the purposes of the system of which the Optical element is a component that the optical element be rotated very quickly and accurately. In these systems the prior art is deficient because the mass of the mounting substantially increases the mass moment of inertia of the optical element, and so makes fast and accurate rotation difficult. FIG. 1 illustrates a typical prior art mount 20 for a diffraction grating 24, having diffraction surface 26. The axis of rotation of grating 24 is A R . Two screws 28A, 28B (only one of which 28A is fully shown) provide adjustment of grating 24 about one axis. A screw 30 provides adjustment about a second axis.
Other commercially available prior art mounts used for non-rotating optical elements (not shown) are gimbal mounts for optical elements which allow adjustment of the optical plane of the optical element about two axes independently by fine pitch micrometer screws. However, these mounts do not provide any axis of rotation for the optical element. That is to say, these commercially available mounts are adjustable but not rotatable.
SUMMARY OF THE INVENTION SUMMARY OF THE
Therefore, for some applications it is desirable to have the optical element fixed to the rotational axis without use of the prior art mount so as to decrease the inertia of the components being rotated, to occupy less space, and to simplify the connection between the driving and driven components.
Prior art mountings do not permit this combination of a mounting with the optical element fixed to the axis of rotation, while permitting necessary adjustments of the position of the optical element relative to the optical system.
The present invention does achieve the object of eliminating the mounting of the optical element while directly coupling the optical element to the rotating means.
The optical element in the preferred embodiment of the present invention is a diffraction grating. Rotation of the grating is used conventionally to selectively aim a portion of a diffracted spectrum of light to a desired point. The two adjustable axes of the optical element make the entire diffracted spectrum pass through this point as the diffraction grating is rotated. In this application the speed and accuracy of moving the diffraction grating from one position to another about its rotational axis is important. Thus direct coupling between the diffraction grating and the output shaft of the driving device is necessary to achieve the low inertia, balanced configuration required for the speed and accuracy.
In the gimballing system in accordance with the present invention, adjustment about one axis causes the spectrum to translate roughly perpendicular to the optical plane of dispersion and adjustment about the other axis causes the spectrum to rotate.
Thus in accordance with the present invention, the optical element is directly coupled to the rotating means and the rotating means is gimbal mounted so as to be adjustable in two dimensions relative to the optical system. Thus the optical plane of the optical element can be adjusted so as to pass through a desired point when the element is rotated.
In another embodiment, the optical element is gimbal mounted so as to be adjustable in one dimension relative to the optical systems.
Since the gimbal mount is attached to the rotating means, no adjustable mounting need be rotated with the optical element, thus minimizing the mass moment of inertia of the optical element.
Thus in accordance with the present invention, the axis of rotation is moved relative to the optical system, which results in the benefits of better balance and less mass moment of inertia compared to the prior art method of moving the optical element relative to the axis of rotation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a prior art diffraction grating mounting.
FIG. 2 shows an exploded view of the preferred embodiment of the present invention.
FIG. 3 shows a side view of the preferred embodiment of the present invention.
Similar reference numerals in different figures refer to similar or identical structures.
DETAILED DESCRIPTION OF THE INVENTION
Shown in an exploded view in FIG. 2 is a galvanometer assembly 30 which applies the gimballing principle in accordance with the invention to align the optical plane of a concave holographic diffraction grating. The galvanometer 9 is a special motor conventionally used to rotate the diffraction grating 10. Galvanometer 9 is preferably commercially available part no. G325DT from General Scanning. The diffraction grating 10 (preferably a custom made concave grating) is directly coupled to the shaft of the galvanometer 9 by use of nut 3, collet 15, and sleeve 16. The galvanometer 9 is attached to the top plate 13 by four screws 8. Insulators 4 and insulator 12 conventionally thermally insulate the galvanometer 9 from the top plate 13. The top plate 13 is attached to the bottom plate 14 by the screw 1 and separated from bottom plate 14 by pivot spacer 5. Top plate 13 and bottom plate 14 are both preferably circular and about 2.5 inches (6.3 cm) in diameter, and both preferably are conventionally fabricated from aluminum with a black anodized finish. Top plate 13 is preferably about 0.25 inches (6.3 mm) thick; bottom plate 14 is preferably about 0.125 inches (3.1 mm) thick.
Gasket 11 is a gasket used to prevent light from entering between the top plate 13 and bottom plate 14. The top plate 13 is forced toward the bottom plate 14 opposite the pivot spacer 5 by the spring 6 and shoulder screw 2. Two adjustment screws 7A are preferably threaded through the top plate 13 and push off the bottom plate 14 in opposition to the spring 6 separating the two plates 13, 14. These two adjustment screws 7A are located midway between the pivot spacer 5 and spring 6, and on opposite sides of the galvanometer 9. Use of these two adjustment screws 7A in opposition to the spring 6 tilts the top plate 13 relative to the bottom plate 14 and allows for alignment about two axes. The two axes A1, A2 pass through the point established by the spacer 5 and screw 1, and the locations of adjustment screws 7A.
Axis Al is the axis of rotation for optical dispersion translation, and axis A2 is the axis of rotation for optical dispersion rotation. Thus, with the bottom plate 14 mounted to the optical system the alignment can be made with respect to the optical system and the desired aiming of the spectrum achieved. Adjacent to the previously described adjustment screws 7A are two additional adjustment screws 7B which pass through the top plate 13 and thread into the bottom plate 14 to lock the alignment. The top plate 13 has a clearance hole and the bottom plate 14 is threaded. Two dowel pins 17 maintain the orientation between the top 13 and bottom plates 14. The dowel pins 17 are also used to align the galvanometer assembly with the optical system.
FIG. 3 shows the galvanometer assembly assembled, in side view. Visible are diffraction grating 10, collet 15, nut 3, sleeve 16, dowel pins 17, bottom plate 14, top plate 13, spring 6, shoulder screw 2, screws 7A, 7B, and galvanometer 9.
Galvanometer 9 is thus firmly attached to top plate 13, and galvanometer 9 and top plate 13 are gimballed relative to bottom plate 14, which is attached to the framework 32 of the optical system (i.e., a spectrophotometer instrument, not shown).
The adjustment of the galvanometer assembly in the preferred embodiment is made at the factory when the optical system is assembled. The adjustment is made by adjusting the adjustment screws 7A. Then the adjustment screws 7B are tightened to hold the adjustment just made against shock. The object of the adjustment is to make the plane of optical dispersion of the grating parallel to the plane of the bottom plate 14, and pass through a desired point when the grating 10 is rotated via collet 15 which is fixed to the output shaft of galvanometer 9.
In alternate embodiments, instead of using a spring loaded mechanism and adjustment screws, the top 13 and bottom plate 14 are adjusted relative to each other by means of wedges, shims, or cams. Any other kind of conventional one or two dimensional mechanical adjustment is used in other embodiments of the invention.
The present invention, in yet other embodiments, is not limited to diffraction gratings or spectrophotometry but is applicable to any rotating optical element where the optical plane is to be adjusted relative to the axis of rotation of the optical element. | An improved mounting for a rotating diffraction grating assembly as used in a spectrophotometer directly connects the grating to the galvanometer that rotates the grating. The galvanometer is gimbally mounted on a plate so that its position, and that of the grating, can be adjusted so that the plane of dispersion of the grating passes through a desired point when the grating is rotated. | 8 |
BACKGROUND OF THE INVENTION
The invention relates to an apparatus for the inspection of containers, particularly bottles, which are transported on a carousel conveyor and from which gas samples are taken to check for contamination.
Such an apparatus is known from EP-A 0579952, which corresponds to U.S. Pat. No. 5,365,771 and is assigned to the assignee of the present invention. In the apparatus described in that publication, the lines running from the sampling probes to the distributor head are connected to the moving part of the distributor head in two concentric circles. Two testing instruments, usually mass spectrometers, are connected to the fixed part, each being permanently assigned to one of the circles of connections. With the apparatus known from EP-A 0579952, operation is possible only when both mass spectrometers are functioning. If one of the instruments need servicing, the apparatus is immobilized.
SUMMARY OF THE INVENTION
The principal object of the invention is to avoid this drawback. This is achieved, in an apparatus of the above-mentioned kind, by modifying the connections from the fixed part of the distributor head to the mass spectrometers to enable either or both of the spectrometers to be used.
By enabling a single mass spectrometer to be optionally connected to both circles of connections, it becomes possible to inspect all bottles with a single test instrument or mass spectrometer. If a second mass spectrometer is provided, it can be serviced, and, after it has been serviced, operation with two mass spectrometers can easily be restored. If desired, it is also possible to operate with one mass spectrometer for an extended period until it becomes necessary to increase the bottle throughput, when the second mass spectrometer can easily be brought into use.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention will now be described in detail, by way of example, with reference to the drawings, in which:
FIG. 1 is a view, partly in section, of a distributor head;
FIG. 2 is a top view of the rotating disk of the distributor head;
FIG. 3 is a view of the fixed disk of the distributor head;
FIG. 4 is a detail view, partly in section, of the distributor head, with a first embodiment of the distributor plug;
FIG. 5 is a detail view, partly in section, of the distributor head, with a second embodiment of the distributor plug;
FIG. 6 is a partial view of the fixed disk for the embodiments shown in FIGS. 4 and 5;
FIG. 7 shows one embodiment of the fixed part of the distributor head, drawn partly in section;
FIG. 8 is a view of the fixed part of the distributor head according to the embodiment in FIG. 7; and
FIG. 9 is a schematic view of a further embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a distributor head for the gas samples withdrawn from the bottles to be inspected, basically as known from EP-A 579952. The bottles run in a carousel (not shown) arranged underneath the distributor head, and sampling probes dip into the bottles to remove samples of gas. These gas samples pass via pipes and connections, four of which (2, 3, 4, 5) can be seen in FIG. 1, to the lower disk 7 of the distributor head, which rotates with the carousel. FIG. 2 is a top view of this disk, showing the arrangement of the connections and of the corresponding passageways (8, 9, 10, 11 in FIG. 1) in the disk. The upper disk 12 of the distributor head, which is fixed, has a suction connection 13 leading to a suction pump (not shown) and two connections 14 and 15 each for a pipe leading to the respective inlet of a mass spectrometer, of which there are two (these are not shown in the drawings). The suction connection communicates with two concentric suction chambers 17 and 18. In FIG. 3, these suction chambers 17 and 18 are represented by broken lines. It will be seen that the suction connection communicates with the chambers 17 and 18 at three points. This is preferable to a single point of communication. The suction chambers extend almost around the entire disk, but stop short of a sector in which the connections 14 and 15 for the mass spectrometers are located and in which two passageways 19 and 20 assigned to these connections extend.
The function of the distributor head is basically similar to that of the distributor head known from EP-A 0579952, U.S. Pat. No. 5,365,771. At any given time, two connections (2, 3 in FIG. 1) are in communication via the passageways 19 and 20 with the connections 14 and 15 ie. with the mass spectrometers, and the individual gas samples pass to the mass spectrometers. At the same time all other connections (4, and 5 in FIG. 1) are in communication with the suction pump via the passageways 17 and 18, so that gas is drawn into the distributor head from the bottles coupled to them. Upon further rotation of the lower disk 7 with respect to the fixed upper disk 12, the next two connections are then brought into communication with the passageways 19 and 20 and the gas samples pass from the corresponding bottles to the mass spectrometers etc. Thus the action of the distributor head means that at any given time two adjacent gas samples are being routed to the two mass spectrometers, while gas samples are being extracted from the other bottles and are being made ready for transmission to the mass spectrometers.
In the example shown, the passageways 19,20 are arranged in a replaceable plug 22 which is inserted laterally into the fixed disk 12. The plug 22 can be removed and replaced by a plug 21 having a different arrangement of passageways 23,24, as seen in FIG. 4, which shows a detail view of the distributor head 1, with the same reference numbers designating the same parts as before. Here, the passageways 23,24 are formed so that the gas samples pass only to the mass spectrometer communicating with the connection 14. The mass spectrometer communicating with the connection 15 is therefore not in use, and can be serviced or repaired. FIG. 5 shows another embodiment with a plug 21' and passageways 23' and 24', with gas samples passing to the mass spectrometer communicating with the connection 15. To prevent the gas samples from the connections 2,3 from reaching the mass spectrometer simultaneously, it is necessary to shorten the passageways 19 and 20 in the example shown, so that the angular offset of the connections (cf. FIG. 2) between the two concentric circles of connections is sufficient to ensure a sequential feed of gas samples from the two circles of connections to the single mass spectrometer.
FIG. 6 shows the shortening of the passageways 19,20 by means of studs 25,26 and 25',26', inserted in the disk 12, which form part of the passageways 19 and 20 respectively, and can be turned about a vertical axis (parallel with the carousel axis) so that the respective passageways 19 and 20 is lengthened or shortened. FIG. 6 shows the setting with short passageways; FIG. 3, the setting with long passageways.
FIG. 7 shows a further embodiment of the invention, illustrating the upper, fixed disk 27 of the distributor head in a partly sectioned view; the lower disk 28 is shown in outline only. The same reference numbers denote the same parts as in the preceding embodiment. In this example the upper, fixed disk has only a connection 29 for one mass spectrometer, and passageways 30 and 31 are provided in the disk 27 to connect both concentric circles of connections to the single mass spectrometer by the shortest route. Here again, the angular offset of the connections on the lower disk ensures a sequential connection of the individual gas sampling lines to the mass spectrometer. The disk 27 is installed on the distributor head in place of a disk of the form previously described with two separate passageways and two connections for two mass spectrometers, and one of the two mass spectrometers can communicate with the connection 29 whilst the other mass spectrometer is available for servicing. After servicing, the disk 27 can be replaced with a disk with two passageways (as known from EP-A 0579952). FIG. 8 shows a view of the fixed disk 27 from above, in which the passageways 17,18 and 19,20 are clearly seen.
By providing a sufficient angular offset of the connections and shortened passageways 19,20, it is possible to ensure that eg. the connection on the inner circle of connections does not reach the passageway 20 until the preceding connection on the outer circle has moved away from the passageway 19. In this way, a controlled succession of gas samples is assured, with no intermingling. A blind connection 33 may be provided on the disk for parking the redundant connecting line for a mass spectrometer which is not in use, thus protecting the line from contamination. Instead of the two converging passageways 30 and 31, the disk could be provided with eg. a horizontal link between the passageways 19 and 20, with a link to the connection 29, in an inverted T arrangement.
Instead of mass spectrometers, other testing instruments for gas analysis can of course be provided, eg. pulse fluorescence spectrometers.
FIG. 9 shows a variant of the invention in which, instead of a replacement part on the distributor head, an electrically controllable valve 35 is connected between the connections 14 and 15 on the fixed disk 12 and test instrument MS1 (the first mass spectrometer) for the period of repair or servicing of test instrument MS2 (the second mass spectrometer). The valve 35 is in place during the period of repair or servicing, and is subsequently removed, in a similar fashion to the replaceable plug arrangement (the latter is depicted in FIG. 9, but is not needed here; in place of the plug, the fixed disk 12 would in this case extend to the moving disk 7). The gas paths are switched by means of the electrically controllable valve to divert the gas samples from the connections 2,3 alternately to the operative analysing instrument MS1 in a timed (triggered) manner. In place of the valve 35 which is put in place only when the need arises, it is possible to provide a valve arrangement 36 (FIG. 10) which is permanently connected to the connections 14,15 and to the two test instruments, with valves for switching the gas samples to both test instruments or to one test instrument only, as | On a distributor head for distributing gas samples removed from bottles requiring inspection to the connections for two mass spectrometers, the feed passageways form alternative paths. These different paths are contained in a replaceable part or a switchable valve arrangement. This allows easy changeover from operation with two mass spectrometers to operation with one mass spectrometer, so facilitating servicing of the mass spectrometers. | 6 |
This is a continuation of application Ser. No. 07/851,871 filed on Mar. 16, 1992 now abandoned.
TECHNICAL FIELD
This invention relates generally to metal surface finishing and more particularly to an apparatus for microfinishing metal surfaces on various machine components.
BACKGROUND OF THE INVENTION
"Microfinishing" or "superfinishing" as it is known in the art, is a surface finishing process wherein a grinding means is brought to bear against a workpiece which has been previously rough ground. Microfinishing is a low velocity abrading process which generally follows rough grinding. Because microfinishing incorporates lower cutting speeds than grinding, heat and pressure variants may be minimized to provide improved size and geometry control. Those skilled in the art recognize that surface quality or roughness is measured in roughness average values (R a ) wherein R a is the arithmetical average deviation of minute surface irregularities from hypothetical perfect surfaces. Microfinishing can provide surface quality of approximately 1 to 10μ in. (0.025 to 0.25 μm). Bearing surfaces of crankshafts, cam shafts, power transmission shafts in similar machine components that rotate on journal bearing surfaces generally require this surface finish for satisfactory operation.
Conventional mass production microfinishing machines have the ability to finish all the bearing surfaces on a workpiece in one operation. These machines contain a plurality of abrasive tape segments which are aligned with respect to the bearing surfaces. In operation, the workpieces are rotated as the microfinishing machine causes abrasive tape segments to contact and thus finish the bearing surfaces. These large multi-abrading machines are capable of successive steps in one operation including rough grinding, grinding and microfinishing.
As is common in large scale production, failures may occur at one or more of the grinding areas or abrasive tape positions. As a result, workpieces may be produced with one or more bearing surfaces (but less than all bearing surfaces) which are not finished to the required surface quality specifications. In such cases, the grinding machine operator must then remove and scrap the defective workpiece. Because microfinishing is the final stage in surface treatment operations, i.e. after rough grinding and grinding, the scrapping of microfinished parts results in a substantial loss of both material and labor to the machinist.
Microfinishing processes are used in automotive applications in the manufacture, repair and rebuilding of internal combustion (IC) engines. Such engines not only require finely finished bearing surfaces for engine efficiency, but also for increased durability and longevity. In the initial manufacturing stage, crankshaft and camshaft bearing surfaces are microfinished to particular roughness specifications by previously mentioned, conventional mass production microfinishing machines.
In the repair or rebuilding stages, engine components such as crankshafts and cam shafts from faulty engines or older engines, are removed and reground to remove ten to thirty-thousandths of an inch of stock from the existing bearing surfaces. The bearing surfaces of these components are then polished or microfinished by placing the respective workpieces on a lathe and manually bringing a microfinishing material in contact with the rotating bearing surfaces. This microfinishing material is often a section of abrasive material mounted on a support correspondingly shaped to the bearing surface. It is generally recognized in the industry that these manual finishing operations are inadequate for achieving finished surfaces of standard quality.
Automotive repair and rebuilding operations microfinish very low volumes of engine components with respect to standard manufacturing operations. Special purpose crankshaft finishing machines such as disclosed in U.S. Pat. No. Re. 31,593 to Judge, Jr., reissued Jun. 5, 1984, are designed for low and medium volume workpiece production. These manufacturing machines are expensive and inappropriate for very low volume workpiece production or repair. Finishing machines of the type disclosed in the Judge, Jr. patent require programming of a computer controller for each different workpiece that requires finishing.
Automotive repair and rebuilding operations reclaim and refinish workpieces from hundreds of various internal combustion engines with different designs. Programmably controlling a finishing machine to accept each individual workpiece that requires microfinishing from different internal combustion engines is uneconomical and inefficient.
SUMMARY OF THE INVENTION
The surface polishing assembly of the present invention has been developed to meet the need for a manually controlled, low volume microfinishing machine that is capable of achieving finished surfaces of consistent quality on selected surfaces of previously incorrectly finished or worn workpieces. The surface polishing assembly has the versatility to accept many various families of machine components or workpieces which require bearing surface control finishing. The present invention, for example, can accept various families of cam shafts, crank shafts, axle shafts, transmission shafts, and compressor shafts without the need for programming of control sequences.
The present invention is also uniquely capable of serving as a manufacturing repair machine for correcting bearing surfaces on machine components previously microfinished by large, high volume microfinishing machines or as a very low volume microfinishing machine for automotive service repair and rebuilding operations.
The polishing assembly includes a pair of polishing arms pivotably affixed to a polishing body and adapted to receive various surface grinding materials for finishing bearing surfaces on workpieces. The polishing body is attached to a base which is movable with respect to the workpiece along the axis of rotation of the workpiece. A pair of stabilizing plates are employed to restrict the polishing arms to movement in a plane substantially perpendicular to the axis of rotation of the workpiece and are adjustably attached to the base.
In operation, the polishing assembly is manually indexed, bringing the polishing arms to a position adjacent the bearing surface to be microfinished. This manual indexing affords accurate and rapid operation and also allows for the accommodation of many families of machine components. The microfinishing machine operates without the need for time-consuming and expensive pre-programming of numerical control systems needed to index and operate automotive microfinishing machines.
Accordingly, it is an object of the present invention to provide a manually controlled surface polishing repair tool that is capable of microfinishing selected surfaces of previously incorrectly or worn finished bearing surfaces on a machine component or workpieces to process and tolerance specifications equal or exceeding automatic control equipment.
Another object of the present invention is to provide a surface polishing assembly including a surface polishing tool that is capable of accepting various families of machine components or workpieces that require microfinishing of selected bearing surfaces without modification.
A further object of the present invention is to provide a surface polishing assembly capable of microfinishing selected bearing surfaces on a previously machined workpiece without requiring pre-programmed computer instructions.
It is a still further object of the present invention to provide an improved surface polishing machine including a surface polishing assembly that is inexpensive to manufacture and operate in medium and low volume production microfinishing processes.
A more specific object of the present invention is to provide a surface polishing tool for use with a power means for rotating a workpiece about an axis having a body defining a track adapted to be positioned adjacent a workpiece including a first and second pivot means, a slide movable on the track, and first and second polishing arms pivotable on a respective pivot means. The polishing arms have a first end adapted to receive a surface grinding means for finishing a workpiece and a second end. A link means connects the slide to the respective second end of the first and second polishing arms for moving the arms about the first and second pivot means from a respective treatment, enabling position adjacent the workpiece to a respective treatment position where the surface grinding means engages the workpiece. The surfacing polishing tool also has an actuating means for movably engaging the slide to move the arms between the respective treatment enabling position and the respective treatment position.
Another more specific object of the present invention is to provide an improved surface polishing machine having a polishing assembly for microfinishing a surface of a workpiece rotatable about an axis having a base movable with respect to the workpiece along and adjacent the axis, a body having polishing arms pivotably affixed to said body and adapted to receive a surface grinding means on one end for finishing the workpiece, a support means affixable to the base for pivotably supporting the body with respect to the workpiece and a pair of stabilizing plates adjustably affixed to the base adjacent the body such that the stabilizing plate sufficiently restrict the body to movement in the plane substantially perpendicular to the axis of the workpiece.
The above objects and other objects, features and advantages of the present invention are readily apparent from the following detailed description of the best mode for carrying out the invention to be taken in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary perspective view of the surface polishing tool of the present invention, partly broken away to show the operation of a polishing arm;
FIG. 2 is a fragmentary elevational view of the polishing tool of the present invention, including a head stock and tail stock for rotating a workpiece;
FIG. 3 is a fragmentary sectional view of the polishing tool of the present invention taken along line 3--3 in FIG. 1 and broken away to show the polishing tool in a treatment position (solid line) and in a pivoted position (phantom line) in response to rotation of the workpiece being treated; and
DETAILED DESCRIPTION OF THE INVENTION
With reference to FIG. 1, a surface polishing tool is shown generally designated by reference numeral 10. Polishing tool 10 is incorporated in the polishing assembly designated by reference numeral 12. Polishing tool 10 is shown having top and bottom polishing arms 14 and 16 which are both pivotally connected to the polishing tool body 18. The polishing arms 14 and 16 are shown in FIG. 1 in a treatment enabling position located above the bearing surface 20 of an automotive cam shaft 22.
Polishing arms 14 and 16 have first ends 24 and 26 adapted to be pivotably connected to body 18 and second ends 28 and 30 which are constructed to accept various families of grinding means depending on the workpiece and the extent of surface finishing required. Various grinding means may be attached to the second ends 28 and 30 of the polishing arms 14 and 16 by any suitable fastening means. FIG. 1 shows one example of a grinding means, an abrasive-coated tape grinding system using tape back-up shoes 32 and coated abrasive tape 34. Common abrasive tape feed and take-up mechanisms are not shown. Other grinding materials include honing stones using diamond, carborundum, garnet, cubic boron nitride and other like substances.
Referring now to FIGS. 1 and 3, there is shown a pair of abrasive-coated tape back-up shoes 32 adapted to receive the bearing surfaces of a workpiece such as cam shaft 22. Abrasive-coated tape 34 is shown adjacent tape back-up shoes 32 to further illustrate the relative positions of back-up shoes 32, abrasive-coated tape 34 and bearing surface 20 during operation of the polishing assembly. Disposed between first ends 24 and 26 and second ends 28 and 30 of top and bottom polishing arms 14 and 16 are identical pairs of connecting members 36 and 38 which extend from respective arms 14 and 16. Connecting members 36 and 38 have throughbores 40 and 42, respectively, which accept pivot pins 44 and 46, respectively.
Polishing arms 14 and 16 have hollowed recesses 48 and 50 disposed between the pairs of connecting members 36 and 38. Upper polishing arm 14 has a handle 52 for bringing upper polishing arm 14 and lower polishing arm 16 forward to the treatment position.
Still referring to FIGS. 1-3, polishing tool body 18 is shown having a pair of extending sections 54 and 56 which have respective throughbores 58 and 60 disposed thereon. The connecting members of the polishing arms are adapted to cooperate with the extending sections of the tool body. Throughbores 40 and 42 are of the same diameter as the throughbores 58 and 60 of the polishing arms to allow pivot pins 44 and 46 to be located inside the throughbores and the polishing arm bores.
The polishing arms 14 and 16 are thus pivotably connected to the polishing tool body 18 by placing the connecting members 36 and 38 of polishing arms within the extending sections 54 and 56. Extending sections 54 and 56 have recesses 62 and 64 for receiving the connecting members of the polishing arms 14 and 16. Pivot pins 44 and 46 are press fit inside the throughbores and work as pivoting members for the polishing arms. The surface polishing tool 10 of the present invention is designed to operate with two polishing arms connected to the polishing tool body but it is contemplated that microfinishing may also be accomplished with just one polishing arm.
Referring to FIGS. 1 and 3, the second ends 28 and 30 of the polishing arms 14 and 16 are pivotally connected to two pairs of metal links 66 and 68. The pairs of metal links 66 and 68 are identical and are disposed on opposite sides of the second ends 28 and 30 of the polishing arms. The pairs of metal links 66 and 68 are connected at their other end to slide block 70 forming a push type toggle mechanism. Slide block 70 is disposed within hollow track 72 defined within polishing tool body 18.
Hollow track 72 is configured to allow sliding engagement between slide block 70 and track 72. Slide block 70 has a threaded hole 74 for receiving and connecting to tie rod 76. Tie rod 76 extends within hollow chamber 78 of sleeve 80 which is attached at one end 82 to track 72.
The actuating end 84 of tie rod 76 is positioned in a fluid motor such as either a regulated hydraulic or regulated pneumatic cylinder, generally indicated as 86 which is attached to the other end 88 of the sleeve 80. This regulated cylinder 86 is operated by a manual control, not shown, to extend the actuating piston 90 of the regulated cylinder 86 to which the tie rod end 84 is connected. As the actuating piston 90 is reciprocated according to the manual operation of the regulated cylinder, the tie rod is reciprocated moving the slide block within track 72. Tie rod 76 and regulated cylinder 86 act in conjunction with slide block 70 as an actuating means for moving the arms to embrace the surface on the workpiece to be finished.
Referring to FIGS. 1 and 3, as slide block 70 moves laterally in a first direction toward the workpiece from a first starting position to a second end position (shown in FIG. 3), it forces the pairs of metal links 66 and 68 to move to a vertical position and thus force polishing arms 14 and 16 to pivot around pivot pins 44 and 46. This brings first ends 24 and 26 having a grinding means to bear upon the workpiece bearing surface. Movement of the slide block 70 in a second direction opposite said first direction, correspondingly opens polishing arms 14 and 16 as shown in FIG. 1.
Different regulated cylinders with different bores and different stroke lengths produce different finishing pressures on the machine component. The pneumatic regulated cylinder 86 shown in FIGS. 1 and 3 has a one-and-one-half inch bore with a two inch stroke length. Using this size cylinder in cooperation with the predetermined pivot position of each polishing arm and the links, the finishing pressure at the grinding means position using approximately 60 psi of line pressure is approximately 200-300 pounds per square inch.
Compressive contact between the grinding means contained on the polishing arms 14 and 16 and the workpiece surface as the workpiece is being rotated about its longitudinal axis creates the microfinishing action that finishes the surface of the workpiece. FIG. 3 shows a polishing assembly of the present invention with one surface polishing tool 10 affixed. Surface polishing tool 10 is pivotally supported upon polishing assembly 12 by a spherical bearing 92 having an aperture 94 adapted to slidably receive sleeve 80. Spherical bearing 92 is journaled within housing 96 which is connected to base 98 of polishing assembly 12.
Still referring to FIG. 3, sleeve 80 is journaled within aperture 94 of spherical bearing 92. Spherical bearing 92 and housing 96 act as a support means for pivotably supporting the surface polishing tool 10 and allows for movement of the polishing tool. Specifically, the use of spherical bearing 92 and housing 96 allow for vertical, pivotal movement of surface polishing tool 10. This vertical movement is important when microfinishing crank shaft pin surfaces. As shown in FIG. 2, crank shaft 100 includes a plurality of cylindrical pin bearing surfaces 102 and main bearing surfaces 140 which must be correctly microfinished for correct operation. Adjustable positive stop 104 is located directly below sleeve 80 to prevent the polishing tool assembly from travelling too far down in the idle position.
For adequate microfinishing of pin bearing surfaces the entire polishing tool 10 must be movable with respect to the throw of the crank shaft pin bearings. This flexibility is necessary because the bearing surfaces of the pin bearings are positioned eccentrically with respect to the center of rotation of the crankshaft. As shown in FIG. 3, the polishing tool 10 can pivot vertically corresponding to the orbit of most crank shafts. The pivotal connection between the spherical bearing 92 and the sleeve 80 allows for surface polishing tool 10 to orbit with conventional pin bearing surfaces located on most crank shafts.
As shown in FIGS. 1 and 3, a pair of stabilizing plates 106 are located directly adjacent the surface polishing tool 10. Stabilizing plates 106 stabilize the surface polishing tool 10 against lateral and angular movement during the finishing operation. Stabilizing plates 106 are positioned adjacent the surface polishing tool 10 with a minimum running clearance between surface polishing tool 10 and the inner walls 108 of the stabilizing plates. This minimum running clearance is achieved by locating the stabilizing plates adjacent the surface polishing tool to a point where sliding contact is made between the surface polishing tool and the stabilizing plates. Spacers 110 are disposed between stabilizing plates 106 to allow for stabilizing pressure to be uniformly applied along the stabilizing plates. The stabilizing plates 106 are affixable to spacers 110 by fastening screws 112.
FIG. 2 shows an alternative embodiment of the present invention with adjustable clamping fixtures 114 and 116 located directly adjacent the stabilizing plates. These clamping fixtures may be utilized to provide additional lateral support during the microfinishing process. Screw fasteners 118 are disposed within adjustment slots 120 as shown in FIG. 1, and are used to lock the clamping fixtures not fully shown in FIG. 1 in place.
The addition of multiple arms and stabilizing plates allows the polishing assembly to go from a single surface polishing assembly to a multiple surface polishing assembly where more than one surface has previously been incorrectly finished. Polishing assembly base 98 may be manufactured in any dimension to accept as many surface polishing tools as needed. Additional stabilizing plates 86 can be positioned adjacent the additional surface polishing tools.
Base 98 incorporates ball bushings or bearings 122 positioned within slide bores 124 within the base 98. These bearings allow the entire polishing assembly 12 to slide along rails 126 contained on polishing support table 128 as shown in FIG. 2.
A handle 130 is affixed to base 98 to aid in sliding the polishing assembly 12 along rails 126. The mobility of polishing assembly 12 is integral to the operation of the polishing assembly. When only one surface polishing tool is being utilized on the polishing assembly 12, successive bearing surfaces can be microfinished on one workpiece by simply indexing the polishing assembly along the axis of the workpiece and finishing a new surface each time. Polishing assembly 12 can be adapted to be affixed to any lathe type rotational grinding machine which is capable of affording lateral movement of the base.
In addition, handle 130 includes a threaded portion 132 that extends into tapped bore 134 which extends into contact with slide rail 126. This handle 130 may be used as a locking means for securing polishing assembly 12 in one location along slide rails 126. Handle 130 can be rotated to a position wherein threaded portion 132 contacts slide rail 126 and acts as a set screw in securing the polishing assembly in one location. This locking means is particularly useful for microfinishing a series of machine components wherein a particular bearing surface along the length of a machine component is out of specification in a number of machine components.
Handle 130 is also utilized when an operator wishes to induce an oscillating lateral movement in the polishing assembly. This lateral oscillating movement is used by the operator to control the resulting surface tool pattern that is created on the bearing or process surface being finished by the grinding means being used. A handle 130 is also used to move the polishing tool assembly laterally along a predetermined length of process surface of the workpiece when the surface to be finished has a greater width than the grinding means.
The surface polishing machine of the present invention as shown in FIG. 2, includes a head stock 136 and a tail stock 138 which together cooperate to rotate a machine component or workpiece such as a crankshaft 100 about its longitudinal center axis. To microfinish the crank shaft shown in FIG. 2, the regulated cylinder must be operated so as to retract (FIG. 1) the actuating piston 90 which in turn retracts the tie rod 76 within the hollow chamber 78. As the tie rod 76 retracts, slide block 70 moves laterally towards the regulated cylinder which in turn moves metal links 66 and 68 such that polishing arms 14 and 16 separate. Crank shaft 100 is next placed within head stock 136 and tail stock 138.
Regulated cylinder 86 is next activated to move actuating piston 90 out and toward polishing tool body 18. Actuating piston 90 moves laterally and thus moves tie rod 76 and slide block 70. As slide block 70 moves toward crank shaft 100, polishing arm 14 and 16 encircle or embrace the bearing surface of crank shaft 100. The operator of the machine regulates the pressure of cylinder 86 until the requisite amount of pressure is supplied upon abrasive-coated tape 34 contained on polishing arms 14 and 16.
This amount will vary according to different polishing surface diameters and widths of the bearing on the machine component. The speed that the workpiece is being rotated by the head stock and the duration the grinding means contacts the bearing surface also effects the roughness average values achieved on the bearing surface. Using a common abrasive tape grinding means with a roughness rating of 20 μm, and rotating the workpiece at 100 rpms, a pressure of approximately 100 psi for 15 seconds induces a roughness value of approximately 15 R a .
The surface polishing assembly according to the present invention, as stated earlier, can be used in large scale manufacturing processes in the industry to recover workpieces scrapped at the microfinishing stage. This is accomplished by removing the scrapped workpiece from the microfinishing machine after an out of specification or incorrect bearing surface has been identified and installing it within the surface polishing assembly of the present invention.
The machine operator may then microfinish the particular bearing surface to the required specification, and thus reclaim the workpiece from scrap. As is known in the industry, machine components that are at the microfinishing stage represent the highest economic investment in the manufacturing process and it is thus very desirable to reclaim the workpiece at these late stages.
Manual microfinishing procedures of the prior art are inherently subjective to the operator performing the procedure and thus may be inadequate in achieving standard surface finishes required for modern internal combustion engine components. The surface finishing assembly of the present invention is able to achieve standard surface finishes on a consistent basis, with consistent quality, and are able to achieve microfinishing levels suitable for modern internal combustion engine components.
Automotive repair and rebuild operations, as stated previously, often remove machine components from engines and microfinish bearing surfaces contained on those components. The surface polishing assembly of the present invention can be utilized to microfinish these various components with a degree of standardization that is higher than prior art procedures. In addition, the surface polishing assembly is configured to accept machine components from many different internal combustion engines. The surface polishing assembly can thus accept crankshafts and camshafts from single cylinder, to multiple cylinder engines without significant modifications.
It can be seen from the above disclosure, that the surface polishing assembly of the present invention is flexible enough to accommodate many various workpieces and can also surface finish many different surfaces on a particular workpiece. The ability to accept many different machine components and also to finish many different surfaces along the component without having to program automatic computer sequences makes the present invention economically desirable as compared to other large, dedicated microfinishing machines known in the industry.
While the best mode for carrying out the invention has been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention as defined by the following claims. | A universal surface polishing assembly movable along the longitudinal axis of a workpiece including a pair of polishing arms with a surface grinding material affixed to each end of the polishing arms respectively, a regulated cylinder for actuating the polishing arms onto the machine component bearing surface, and a pair of stabilizing plates located directly adjacent the polishing arms for stabilizing the polishing arms during the microfinishing operation. The surface polishing assembly is designed to be adapted to various machines having means for workpiece rotation such as grinders, lathes, mills etc. Many different machine components that require microfinishing of various bearing surfaces can be finished in the present invention due to the manual indexing ability inherent in the slidable polishing assembly. | 1 |
BACKGROUND OF THE INVENTION
[0001] Mobile networks have evolved such that 3rd generation mobile networks offer many different services that include multimedia messaging, streaming video, parental control, and mobile phone advertisements. The IP Multimedia Subsystem (IMS) is an architectural framework for delivering internet protocol (IP) multimedia to mobile users. The 3GPP developed IMS to evolve mobile networks beyond GSM. IMS allows service providers to deliver Internet services over a variety of networks that include, but are not limited to, GPRS, Wireless LAN, CDMA2000, and fixed line.
[0002] To ease the integration with the Internet, IMS uses Internet protocols such as Session Initiation Protocol (SIP). The purpose of IMS is to aid access of multimedia and voice applications across wireless and wireline terminals. This is done by having a service plane and a bearer plane. The service plane provides different services to wireless terminals across wireless networks. Alternatively, the bearer plane allocates the physical network recourses (i.e. network bandwidth) necessary to provide the services provisioned by the service plane. Further, IMS has allowed Application Servers to apply policies for certain applications to the bearer plane via a functional element known as the Policy and Charging Rules Function (PCRF). The policy framework defined in IMS, for example, allows a subscriber to receive appropriate bandwidth and reductions in latency for viewing of a streaming video (service application). The IMS and MMD standards define how the PCRF is used by application servers (AS) to push or pull policy information about how a user is to use the resources provided by the bearer plane (RF and IP resources at the access network).
BRIEF SUMMARY OF THE INVENTION
[0003] Aspects of the invention allow mobile network users as well as mobile network providers to define policies that are managed across several applications and services. Thus, several application servers and network elements are coordinated to implement a service policy. More specifically, aspects of the invention define service level policies for any service be within an IMS based or non-IMS based wireless network implemented by SIP or non-SIP network elements.
[0004] A service policy is a set of rules that is applied when a subscriber uses a specific service (Web Browsing, Location, Presence, MMS, SMS, PoC, etc). The policy may be applicable on a per-need, per-subscriber basis. A service policy enhances or restricts use of the service functionality by the subscriber. In addition, a service level policy allows definition of service utilization rules that constrain how the service may be used by a subscriber. For example, a parent may restrict the use of her child's cell phone to only one hour per day between the time of 12 noon to 1 pm and 4 pm to 6 pm. Thus, aspects of the inventions allow mobile service subscribers to receive a level of customization for services rendered by a mobile network service provider. Further, mobile network service providers may provide not only custom service to subscribers but also simplifies the provisioning by allowing a single-point of configuration for subscriber based service control policies. Consequently, service level policies have wider scope than bearer level policies such as quality of service in the form of on-demand bandwidth, committed rates of throughput, committed reduction in delay/jitter/latency.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
[0005] FIG. 1 is a schematic diagram illustrating an exemplary IMS network environment, wherein a mobile device communicates with an application server located in an IMS core network via one or more access networks, as contemplated by an embodiment of the present invention;
[0006] FIG. 2 is a schematic diagram illustrating an exemplary implementation of the IMS core network and access networks of FIG. 1 in more detail, in accordance with an embodiment of the invention;
[0007] FIG. 3 illustrates an exemplary implementation of a service policy authorization and utilization control function (SAUCF) that applies a service policy across several applications and services interacting with IMS and non-IMS network elements;
[0008] FIG. 4 illustrates the details in an exemplary process of requesting authorization by an Network Element to a SAUCF;
[0009] FIG. 5 illustrates an exemplary implementation of a SAUCF in network;
[0010] FIG. 6 is an exemplary SAUCF High Level Message flow chart;
[0011] FIG. 7 illustrates an exemplary binding of an individual subscriber to a “trusted group” of subscribers;
[0012] FIGS. 8-11 are flow charts that illustrate an exemplary implementation of service policy rules;
[0013] FIG. 12 is an exemplary message flow diagram that illustrates the mapping of SAUCF messages to Real Time Utilization (Ru) interface messages; and
[0014] FIG. 13 is a flow chart illustrating an exemplary application of service utilization bonuses.
DETAILED DESCRIPTION OF THE INVENTION
[0015] The following examples further illustrate the invention but, of course, should not be construed as in any way limiting its scope.
[0016] FIG. 1 is an exemplary implementation of a system contemplated by an aspect of the invention is shown with reference to an IP multimedia network environment with an IMS enabled core. Note that aspects of the invention are not limited to the type of network depicted in FIG. 1 , but may include other non-IMS networks. FIG. 1 shows one exemplary environment where mobile services are managed on a per subscriber basis. In this aspect, a user device 100 is a mobile device, such as a wireless telephone or a portable computer capable of wireless communication with a plurality of radio access networks ( 102 , 104 ), such as those employing a CDMA-based, GSM-based, or a WCDMA-based standard.
[0017] To enhance the user experience with multimedia based services, the access networks ( 102 , 104 ) are connected to an IP Multimedia Subsystem (IMS) core network 106 that manages IP network sessions in a mobile environment. The IMS core network 106 further includes an application server (AS) 108 , which hosts one or more applications available to the mobile device 100 . The applications hosted by AS 108 include multimedia applications, such as streaming media applications, as well as other applications which require the maintenance of specific quality of service (QoS) guarantees. To expand the variety of applications available to the mobile device 100 via the access networks ( 102 , 104 ), the IMS core network 106 includes a connection to the public Internet 110 . Preferably, the mobile device 100 is a multi-mode entity capable of accessing a plurality of access networks operating based on different network technologies. Examples of a mobile device include but not limited to a mobile phone, Personal Digital Assistant (PDA), and a laptop computer.
[0018] FIG. 2 illustrates an exemplary implementation of the IMS core network 200 and access networks ( 216 , 218 ) of FIG. 1 in more detail. The mobile device 220 and the application server 202 communicate via access networks ( 216 , 218 ) and the IMS core network 200 to establish and maintain a service session for an application launched by a user. In addition to the application server 202 , the IMS core network 200 includes other IMS functions, such as those described in G. Camarillo, M. Garcia-Martin, “The 3G IP Multimedia Subsystem (IMS) Merging The Internet And The Cellular Worlds,” John Wiley & Sons, Ltd., 2006 (second edition), which is incorporated herein by reference in its entirety for everything that it teaches. To this end, the AS 202 is connected to a Serving Call/Session Control Function (S-CSCF) 204 , which is a Session Initiation Protocol (SIP) server that performs session control, SIP registrar, authentication, and other IMS functions via SIP protocol signaling described in J. Rosenberg, H. Schulzrinne, G. Camarillo, A. Johnston, J. Peterson, R. Sparks, M. Handley, E. Schooler, “SIP: Session Initiation Protocol,” RFC 3261, IETF, June 2002, which is incorporated herein by reference in its entirety for everything that it teaches. The IMS core network 200 includes a number S-CSCFs, wherein each S-CSCF has a certain capacity in terms of a maximum number of supported mobile devices (MD) 220 .
[0019] The S-CSCF 204 , in turn, connects to a Proxy Call/Session Control Function (P-CSCF) 206 , which, among other IMS functions, includes user authentication functions and acts as an inbound and outbound SIP proxy server by relaying the SIP requests and responses to and from the mobile device 220 and to and from the IMS core network 200 . As with the S-CSCF 204 , the IMS core network 200 includes a number of P-CSCFs, wherein each P-CSCF has a certain capacity of being able to support a predefined number of mobile devices 220 . The Home Subscriber Server (HSS) 208 is a database of user-related information and contains user subscription data necessary for authentication and authorization of an IP multimedia session associated with a given application. The HSS serves the S-CSCF as shown in FIG. 2 . The user subscription data is contained in a user profile that indicates, among other things, the types of services to which the user subscribes. Additionally, a Policy Function (PF) 210 This in the MMD (3GPP2 specs) is the “Policy and Charging Rule Function (PCRF) is used to authorize the media plane resources and supervise the QoS over the media plane by interfacing with a plurality of Access Gateways ( 212 , 214 ), which, in turn, allocate the access network resources within the corresponding access networks ( 216 , 218 ) in accordance with the QoS constraints required by the multimedia application. Note that the PF 210 is analogous to the Policy and Charging Rule Function (PCRF) in an MMD network architecture. Finally, the Home Agent (HA) 215 is a router typically involved in the Mobile IP (MIP) session registration process, as well as in tunneling of packets when the MD 220 is roaming.
[0020] FIG. 3 illustrates an exemplary implementation of a service policy authorization and utilization control function (SAUCF) 310 that applies a service policy across several applications and services interacting with IMS and non-IMS network elements. Generally,
[0021] FIG. 3 shows a SAUCF interfacing with different network elements in the context of an IMS network. IMS application servers (AS 1 -AS n ) ( 312 , 314 ) and the CSCF 316 utilize the services of the SAUCF 310 via the unique Service Authorization & Utilization Diameter Application (SAUDA) interface. The S-CSCF 316 plays an important part in Voice over IP calls because all calls for a given subscriber traverse the S-CSCF 316 . When no AS ( 312 - 314 ) is involved in a VOIP call, the S-CSCF 316 may request service level policies for a subscriber from the SAUCF. FIG. 3 also shows legacy (non-IMS) application servers such as the MMSC 318 and a Web Proxy 308 . Legacy network elements also utilize the Service Authorization & Utilization Diameter Application interface to the SAUCF 310 to support service level policies. Finally, the services provided by the SAUCF 310 may be utilized by network elements other than application servers. For example, FIG. 3 shows a firewall 306 communicating with the SAUCF 310 that may provide restriction or privacy services to a subscriber. Note that interfaces 332 - 340 carry the Service Authorization and Utilization Diameter Application.
[0022] FIG. 3 also shows network elements and functions shown in FIG. 2 that include the PCRF 326 and HSS 324 . The SAUCF also enforces subscriber level policies for access to the Web Servers 304 through the Internet 302 across a firewall 306 . Further, the CSCF 316 routes signaling for subscribers services to one or more mobile devices 330 through a plurality of Access Gateways ( 320 - 322 ). Note that interfaces 344 - 350 are on the User Plane and carry the data between the mobile and the servers (client-server) and or other mobiles (peer-to-peer). Interfaces 360 - 362 are Tx/Ty interfaces while interfaces 356 - 358 are Sh/Cx Diameter interfaces. In addition, interfaces 352 - 354 are SIP Signaling interfaces.
[0023] FIG. 4 illustrates the details in an exemplary process of requesting authorization by a Network Element 405 to a SAUCF 420 . A Network Element (i.e. application server, firewall, etc.) 405 requests service authorization 410 from a SAUCF 420 . An SAUCF 420 may have several sub-functions that may include a Communication Authorization Sub-Function 425 , Access Authorization Sub-Function 430 , and a Charge Sub-Function 435 . Communication Authorization Sub-Function may include restrictions to certain members of a subscriber in terms of their call destination, calling minutes (time), usage, and content. For example, a family subscriber group may restrict a son's call destination to only his parents' mobile phones. Access Authorization Sub-Functions may include service access and privacy controls to certain members of a subscriber group. For example, a subscriber group may elect not to disclose to advertisers personal subscriber information for coupons on advertiser products and services. Charge Authorization Sub-Function checks the subscriber account to ensure that there are credits available to the subscriber use the requested service. The SAUCF Charging Authorization Sub-Function is used when a charging discount is applicable based on the fact that the subscriber is communicating (any form of communication) with members of the “trusted group.” For other forms of charging that do not involve the “trusted group” the SAUCF defers to the Online Charging System (See FIG. 5 ). After the SAUCF 420 determines whether to deny or authorize the requested service by the Network Element 405 , it sends a Service Authorization or Denial message 415 to the Network Element 405 .
[0024] FIG. 5 illustrates an exemplary implementation of a SAUCF in network. FIG. 5 shows two novel interfaces 555 and 515 and a unique subscriber specific data store with respect to managing mobile services on a subscriber basis. Note that the SAUCF may be implemented in any network element such as, but not limited to an AAA or a HSS. However, the SAUCF may also be implemented as a separate entity. The SAUCF 510 acts as a service manager for all services in the network between network elements for a subscriber group. With respect to the On Line Charging System (OCS) 520 the SAUCF may act as a charging proxy. Authorization requests 555 are sent by any network element (such as an application server) 505 to the SAUCF 510 . In addition, authorization requests may utilize the new “Service Authorization & Utilization Diameter Application” interface with Attribute Value Pair commands (AVPs) that will be described later in this specification. Charging based authorization requests may also be made by network elements as Credit Control Request (CCR) AVPs to describe the way a service is charged. In certain aspects of the invention, the SAUCF supports RFC 4006 (CCR/CCA) because the SAUCF may proxy for the OCS. The SAUCF 510 may pass charging requests to the OCS 520 in the form of a CCR Diameter messages. The SAUCF 510 may apply “trusted groups” discounts for subscribers that qualify. Trusted groups will be described in more details later in this specification.
[0025] FIG. 5 also shows an application server 505 that communicates with a PCRF 542 across a Tx interface 545 and a PCRF 542 that communicates to an access gateway across a Ty interface 550 . Alternatively, the SAUCF 510 uses a Ru interface 615 and bypasses the OCS 520 for network elements that do not require charging authorization but require service level utilization authorization. The Ru interface 515 maps authorization messages 555 to service utilization messages sent to a Subscriber Service Utilization Account 525 . The OCS 520 communicates with the SAUCF 510 across a standard IMS Ro interface 560 .
[0026] The Ru interface 515 may use a modified Diameter application where the Diameter protocol is defined in RFC 3588. The Diameter Ru interface allows network elements to query the service usage credit balance for a given subscriber from the Subscriber Service Utilization Account 525 and provide the ability to withdraw and deposit into the balance. The “Subscriber Service Utilization Account” 525 allows definition of service utilization “buckets” based on “bundled services”. For instance, a “message bundled service” bucket for a subscriber has defined the category “messages” as MMS and SMS. FIG. 5 also shows exemplary available subscriber service credits 530 . For example, the subscriber has service credits equal to 5 MMS/SMS messages, one hour of talk time using VOIP/PTT, and 10 MB of Browsing data.
[0027] FIG. 6 is an exemplary SAUCF High Level Message flow chart. The Service Authorization and Utilization Control Function (SAUCF) 610 becomes a repository of subscriber service level policies. These policies are defined in Policy Decision Points such as the SAUCF 610 and enforced via Policy Enforcement Points such as an Application Server or Application Policy Function (network Element 605 ).
[0028] SAUCF implements policies designed by a subscriber or subscriber group with regard to services provided to a subset of subscribers within a subscriber group. For example, a SAUCF incorporates a parental control service into its policy for a subscriber group. The parental controls include restricting all communication by children to only members of the family (father or mother). Further, parents may restrict their children to only 10 MMS or SMS messages per day between noon and 1 pm and 4 pm-6 pm. In addition parents may restrict children to voice services (such as VOIP or PTT) to only between noon and 1 pm and 4 pm-6 pm.
[0029] The SAUCF service policy may also contain rules for providing advertising services to a subscriber. For example, a subscriber may opt in for discounts or refunds by allowing reception of advertisement messages. For example, no more than 10 advertisement messages (MMS or SMS) per month. Further, SAUCF service policy may also contain rules for subscriber privacy. For example, a subscriber may opt in to disclose personal information to advertisers for a coupon/discount for given products. Subscriber may only allow no more than 10 personal location fixes or presence updates per month. In addition, the SAUCF may incorporate family charging services into its service policy for subscriber group. For example, all communication among members of the family is free, or all messages (MMS and SMS) send to members of the family is 50% off during evening hours.
[0030] As shown in FIG. 6 , a first step is to determine if a subscriber is authorized to use a service is to send a “Service Access Request” message 625 to the SAUCF 610 . The network element 605 may use a Diameter protocol via a modified Diameter Application, namely a “Service Authorization & Utilization Diameter Application”. This modified diameter application is defined with a diameter application ID assigned by the Internet Assigned Numbers Authority (IANA). This Diameter application defines a set of additional attribute-value pairs (AVP) commands to describe the set of service policies desired by the subscriber. Table 1 below describes an exemplary set of additional Diameter AVPs that is supported by the Service Authorization & Utilization Diameter Application.
[0000]
TABLE 1
Command Name
Parameters
Description
Communication-Request
This command requests communication
permission between two end points.
Source-Address
This is the IP address associated with the
subscriber.
Destination-Address
This is the IP address associated with the
destination of any communication
originating from the Source-Address.
Content
This can be a “URL” or a Media Type such
as Audio and Video.
Privacy-Request
This command requests permission to
release to the requestor subscriber (target)
specific data.
Requestor
Identity of source of this request. The
identity may be but not limited to: SIP-URI,
MDN, MIN, Email-Address, IM Address,
and NAI.
Target
Identity of target of this request. The
identity may be but not limited to: SIP-URI,
MDN, MIN, Email-Address, IM Address,
and NAI.
Location
Requestor is requesting “Location”
information about Target. Location
information such as Latitude, Longitude,
and Altitude.
Presence
Requestor is requesting “Terminal Status”
information about Target. The status may
be but not limited to Reachable,
Unreachable, and Busy.
Identity
Requestor is requesting personal
information about the target. Identity
information may be but not limited to Full
Name, Full Address, Mobile Phone
Number, Email Address, SIP-URI, and IM
Address.
Service-Authorization-
This command requests permission to use a
Request
particular service identified by Service-ID
and possibly includes the desired service
utilization.
Requestor
Identity of source of this request. The
identity may be but not limited to: SIP-URI,
MDN, MIN, Email-Address, IM Address,
and NAI.
Target-Subscriber
Identity of target of this request. The
identity may be: SIP-URI, MDN, MIN,
Email-Address, IM Address, and NAI.
Target-Service-Content
URL used to identifies the content of a
specific service.
Service-ID
ID identifying the specific service for
which authorization is being requested.
Example: MMS, LBS, PTT, etc
Utilization-Request-Type
Specifies the type of utilization request.
Exemplary session based types may be:
Initial-Request
Update-Request
Final-Request
Exemplary event based types may be:
One-Time-Event
Requested-Service-Units
Contains the amount “service” units desired
by the requestor. For example, for MMS
Requested-Service-Units may be the
number of MMS messages. Another
example may be a VOIP call where the
Requested-Service-Units may be the
number of minutes of conversation. This
parameter forces a response containing the
“Granted-Service-Units” AVP which
defines the number of service units granted
by the SAUCF.
Used-Service-Units
Contains the amount “service” units
consumed by the requestor.
Identity-Request
Subscriber-Address
This is the IP address associated with the
subscriber. If this subscriber has a live data
session for which the AAA has successfully
authenticated this subscriber then the
response to this command is the private-
identifier known as Network Access
Identifier (NAI) corresponding to the
subscriber. If no valid session exists for this
subscriber then the AAA returns an error
code.
Target -Address
This is the IP address associated with the
target of the subscriber communication. If
this target has a live data session for which
the AAA has successfully authenticated this
subscriber then the response to this
command is the private-identifier known as
Network Access Identifier (NAI)
corresponding to the target. If no valid
session exists for this target subscriber then
the AAA returns an error code.
Charge-Request
This command is required for any charge
authorization request and may include
Credit Control Diameter parameters
destined for the On Line Charging System.
Requestor
Identity of source of this request. The
identity may be but not limited to: SIP-URI,
MDN, MIN, Email-Address, IM Address,
and NAI.
Charged-Service-ID
ID identifying the specific service for
which charging is being requested.
Example: MMS, LBS, PTT, etc.
Any Additional AVPs in
Credit Control Application
as defined in RFC 4006
“Credit Control
Application”
[0031] As shown in FIG. 6 , in a step 1, a “Service Access Request” message is a subset of the Service Authorization & Utilization Diameter Application AVPs defined in Table 1. For example, when the SAUCF receives the Communication-Request AVP, the SAUCF then sends the Authentication, Authorization and Accounting (AAA) server 615 an Identity-Request, in a step 2 630 , with the Subscriber-Address and Target-Address set to be the Source-Address and the Destination-Address, respectively. These parameters may have been previously received from a Communication-Request. The AAA 615 determines whether a valid data session exists for this subscriber/target and returns the Network Address Identifier (NAI) that uniquely identifies the subscriber and target to the operator network.
[0032] The service level policies defined in the Service Authorization and Utilization Control Function are bound to a given subscriber based on the NAI. The NAI is used in the SAUCF to bind subscribers to service policy rules associated with this subscriber. Further, each NAI in the SAUCF is also bound to a set of public-identities (aliases) associated with this subscriber as shown in FIG. 7 . The following minimal aliases are defined but are not exhaustive SIP-URI, MDN, MIN, Email Address, and Instant Message Address.
[0033] Each subscriber in the SAUCF is bound to a “trusted group” of subscribers defined in FIG. 7 . Each subscriber is also identified via NAIs and aliases. Service policy rules govern the binding between a given subscriber and the trusted group as shown in FIG. 7 . In a step 3 ( 635 ) of FIG. 6 the SAUCF using the NAI for this subscriber, retrieves his/her aliases and also other aliases of the trusted group. The SAUCF then proceeds to apply the service policy rules 620 .
[0034] FIG. 7 illustrates that each subscriber is bound to a “trusted group” of subscribers. Each subscriber is also identified via NAIs and aliases. Service policy rules govern the binding between a given subscriber and the trusted group. For example, a trusted group 710 may be the mother 715 and father 720 of a subscriber group. A son 705 is bound by the service rules imposed by the mother 715 and father 720 . An exemplary service rule may be that the son may only call mother and father and no one else. Thus, if the son 705 requests to call another person, then the SAUCF implements the service rule and denies the request to the son.
[0035] FIGS. 8-11 are flow charts that illustrate an exemplary application of service policy rules. A first set of steps may be to apply communication service rules. For example, a son may be restricted to call only his parents. Consequently, at a first step 805 , a SAUCF may match the Target NAI against the Subscriber Trusted Group (parents) NAIs. If a match is not found then service access is denied 820 as shown in step 4.b 645 in FIG. 6 . If a match is found, then the SAUCF may match the allowed communication times by the requesting subscriber with the requesting time of the subscriber at a step 810 . If a match is not found then service access is denied 820 as shown in step 4.b 645 in FIG. 6 . For example, if the requesting subscriber is a son who is calling his mother at 3 pm but is only allowed to call his parents between 5 pm and 7 pm, then service access is denied to him. At a next step 815 , a SAUCF matches the requested content against the disallowed content for the subscriber. If a match is found (content disallowed) then service access is denied 820 as shown in step 4.b 645 in FIG. 6 . For example, if a subscriber requests streaming video from a particular website, and the trusted group has assigned the particular website as disallowed content, and then the subscriber is denied service 820 . However, if a match is not found, the SAUCF may continue by applying Security and Privacy Service rules 825 .
[0036] At a next step 905 , the SAUCF determines whether to apply Security and Privacy rules based on whether a Privacy Request AVP is present (See Table 1). It may then match the Location, Presence, or Identity parameter against the setting for the subscriber's trusted group. If a match is found then service access is denied 920 as shown in step 4.b 645 in FIG. 6 . Next, the SAUCF may apply Service Authorization and Utilization rules. At a next step 910 , the SAUCF matches the Service ID against the Service ID allowed for the subscriber. If a match is found and the Target Service Content parameter is present (See Table 1), then the SAUCF matches the Target Service Content against the disallowed content for the subscriber at a next step 915 . If a match is found then service access is denied 920 as shown in step 4.b 645 in FIG. 6 . However, if a match is not found the SAUCF may continue to apply further service authorization and utilization rules 925 .
[0037] A set of steps 1005 - 1025 apply further exemplary service authorization and utilization rules. At a next step 1005 , the SAUCF applies service utilization bonuses if it determines that the subscriber has not exceeded its service utilization quota. For example, if a Charging Request is present and a Charged Service ID does not match the Service ID, then the SAUCF checks if the Requested-Service-Units parameter (See Table 1) is present and a charge discount is applicable. If so, then a bonus is applied. Note that checking whether the Charging Request is present and a Charged Service ID does not match the Service ID shows that the SAUCF is a proxy for the OCS and that any charging requests are handled by the OCS. Further, it ensures that the “Subscriber Service Utilization Account” is accessed by either the SAUCF or the OCS but not both. At a next step 1010 , if the Requested Service Units or Used Service Unit AVP are present (See Table 1) then they are mapped to the Ru interface as shown in FIG. 12 to send to the Subscriber Service Utilization Account. At a next step 1015 , the SAUCF determines whether the Subscriber Service Utilization Account can satisfy the requested service. If not, then the requested service is denied 1020 . If so, then the SAUCF may apply “Trusted Group” charge service rules 1025 .
[0038] A set of steps 1105 - 1120 implement exemplary “Trusted Group” charge service rules. At a next step 1105 , the SAUCF determines whether a “Trusted Group” charge discount is applicable. At a next step 1110 , the SAUCF then applies the discount. At a next step 1115 , the request message is forwarded to the OCS. At a next step 1125 , the service is allowed as shown in Step 4.a ( 640 ) in FIG. 7 .
[0039] As discussed previously, the Ru (Real Time Utilization) interface is a modified Diameter application that allows network elements to query the service usage credit balance (held in a network element called the “Subscriber Service Utilization Account”) for a given subscriber, and provide the ability to withdraw and deposit into the balance. The “Subscriber Service Utilization Account” allows definition of service utilization “buckets” based on “bundled services”. For instance, a “message bundled service” bucket for a subscriber has messages defined as MMS and SMS.
[0040] The table below describes a modified set of Diameter AVP commands that may be supported by the Real Time Service Utilization Diameter application.
[0000]
TABLE 2
Command Name
Parameters
Description
Service-Utilization-Query
This command queries the balance of
the subscriber utilization account. The
response is the number of units
available for the requestor for this
Service-ID.
Service-ID
ID identifying the specific service for
which balance query is being requested.
Example: MMS, LBS, PTT, etc.
Requestor
Identity of source of this request. The
identity may be: SIP-URI, MDN, MIN,
Email-Address, IM Address, and NAI.
Service-Utilization-
This command request a service unit
Withdrawal
balance withdrawal from this
subscriber's utilization account. The
response is the number of units granted
for this request.
Service-ID
ID identifying the specific service for
which a balance service unit withdrawal
is being requested. Example: MMS,
LBS, PTT, etc.
Requestor
Identity of source of this request. The
identity may be: SIP-URI, MDN, MIN,
Email-Address, IM Address, and NAI.
Service-Units-Withdrawn
The number of service units to be
withdrawn from the subscriber's
utilization account
Service-Utilization-Deposit
This command requests a service unit
deposit to the balance of this
subscriber's utilization account.
Service-ID
ID identifying the specific service for
which a balance service unit deposit is
being requested. Example: MMS, LBS,
PTT, etc.
Requestor
Identity of source of this request. The
identity may be: SIP-URI, MDN, MIN,
Email-Address, IM Address, and NAI.
Service-Units-Deposited
The number of service units to be
deposited into the subscriber's
utilization account
[0041] FIG. 12 shows the service utilization messages received by the SAUCF are mapped to the Ru Interface. The Ru interface is between the SAUCF 1205 and the Subscriber Service Utilization Account 1210 . For example, a Service Authorization Request and a Requested Service Units message 1215 received by the SAUCF 1205 are mapped to the Ru interface as a Service Utilization Withdrawal message 1220 to the Subscriber Service Utilization Account 1210 . Another example is that a Service Authorization Request and a Used Service Units message 1225 received by the SAUCF are mapped to the Ru interface as a Service Utilization Deposit message 1230 to the Subscriber Service Utilization Account 1210 .
[0042] FIG. 13 is a flow chart illustrating an exemplary application of service utilization bonuses. Discounts may be defined in the SAUCF as part of the charging rules. Discounts in the SAUCF apply both to the price of the service as well as the number of units utilized for that service. For the number of units utilized for that service the discount becomes a cumulative bonus. For example, sending an MMS message may cost 10 cents and sending MMS messages to members of the family produces a 50% discount. Then sending the first MMS message costs 5 cents and sending the second also costs 5 cents but the subscriber has gained an additional MMS message as a bonus. That is, the subscriber sent two MMS messages but consumed only one. Note that the SAUCF accumulates bonuses on a per service basis. So if the 50% discount continues to apply and the subscriber sends 2 MMS messages and 2 SMS messages than the subscriber will only have consumed one MMS and one SMS messages, respectively. The SAUCF may need to maintain a per-subscriber, per-service counter called a Service-Units-Bonus to support the cumulative bonus for service unit discounts as shown in FIG. 13 . At a step 1305 . a Service-Units-Bonus counter is initialized with a value of zero (0%) units for this subscriber for this service. Each time a service unit is consumed the discount is applied. A service unit may be considered consumed when a one time service utilization or charging event is received ( 1310 ) or when a service session is over ( 1315 ). Thus, at a step 1302 , the SAUCF determines whether a completed service unit has been consumed. If so then it applies the bonus at a step 1325 , for example, Service-Units-Bonus=Service-Units-Bonus+Discount-Rate. At a step 1330 the SAUCF sets the value of “Service-Utilization-Deposit” to zero. At a step 1335 the SAUCF determines whether Service-Units-Bonus greater than or equal to 100%. If so, then at a step 1340 value of “Service-Utilization-Deposit” is incremented by 1 unit. At step 1345 , Service-Units-Bonus=Service-Units-Bonus−100%. However, if Service-Units-Bonus is less than 100%, then the SAUCF sends a “Service-Utilization-Deposit” to the Subscriber Service Utilization Account at step 1350.
[0043] A service unit is consumed when a one time service utilization or charging event occurs or when a service session is over. A one time service utilization or charging event may be the following: (a) A Service-Authorization-Request AVP with a Requested-Service-Units AVP is received by the SAUCF and the unit-type is (a) One-Time-Event; or (b) A Credit Control (RFC4006) request with “Event-Request” AVP is received. A service session is over when the following occurs: (a) the SAUCF keeps track of units consumed for Service-Authorization-Requests by tracking the “Granted-Service-Units” returned by the Subscriber Service Utilization Account; (b) the SAUCF keeps track of chargeable consumed units by tracking the “Granted-Units” returned by the On Line Charging System; (c) a service session is over when a Service-Authorization-Request AVP with a Requested-Service-Units AVP is received by the SAUCF and the unit-type is Final-Request and “Used-Service-Units” AVP; and (d) a chargeable service session is over when a Credit Control message is received with a request type of “Terminate” and Used-Units. Note that time constraints may also be included in the calculation of the discount. For example, time constraints may indicate when discounts apply.
[0044] The SAUCF may also apply charging discounts to a subscriber for being a member of Trusted Groups. The SAUCF may apply special discounts that cover multiple services tied to certain communication constraints such as the constraint of communication within a “trusted group”. This is not possible by utilizing an On Line Charging System (OCS) alone. An exemplary application of Trusted-Group discounts may be that the SAUCF on receipt of a Charge-Request AVP may do the following: (1) retrieve the price for this service from the OCS; (2) send a Credit Control message with Price-Inquiry AVP to the OCS for this Charged-Service-ID; (3) apply the Trusted-Group discount for this subscriber using price returned in the Credit Control Answer message; (4) Compute Discount=Service Price*Trusted Group Discount Rate; and (5) send a Credit Control message with Refund AVP which reflects the Discount:
[0045] 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.
[0046] 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.
[0047] 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. | An apparatus is described for managing mobile network services. The apparatus includes a service authorization and utilization control function (SAUCF) element configured to authorize a mobile network service request by acting as a service manager configured to centrally coordinate service authorizations for multiple network services associated with an individual subscriber account by evaluating a service policy defining user access spanning the multiple network services. The service policy includes (a) communication authorization controls affecting permission for a user associated with the subscriber account to access a mobile network service in accordance with one or more criteria applicable to a bundled service category; and (b) charging controls for determining whether a subscriber account includes sufficient credits to use the mobile network service. A real time utilization interface is configured to transmit messages between the SAUCF element and a subscriber service utilization account. | 7 |
FIELD OF THE INVENTION
The present invention is related to head or cervical immobilization devices and more particularly to an improved immobilizer for constraining the head and upper cervical portions of a person against movement during transport on a rigid patient support back board and during transport within a medical facility and during medical evaluation including techniques such as x-rays, CT scans and the like.
BACKGROUND ART
It has long been recognized that it is of vital importance to stabilize the head and cervical portions of accident victims or those who are suspected of having been exposed to cervical injuries. It is well understood that very serious and permanent damage can be done by movement of the head and cervical portions when damage has occurred in the cervical region. Accordingly, with accident victims or others in whom possibility of head or cervical injury exists, the paramedical staff attending the patient at the site and during transference to a medical treatment facility routinely immobilize the head and cervical spinal area of such a patient to attempt to reduce any further injury. Similarly upon arrival of accident victims or the like at a medical treatment facility, medical staff then must assess the patient while ensuring that no additional damage is done during the assessment process. Often the assessment process may involve use of other sophisticated medical equipment located in other areas of the hospital or treatment facility other than the emergency or receiving room. This may involve moving the patient to be subjected to x-ray evaluation or CT scans and the like. During the medical evaluation procedure it is important and desirable that full access be had to the head and cervical area of the patient without moving the patient.
There have been many devices intended to maintain support for the head of a patient during the transport phase from accident scene to medical treatment facility. U.S. Pat. No. 4,182,322 issued Jan. 8, 1980 to Miller discloses a durable lightweight three section cushion which is used to effectively cover and restrain the head of the accident victim when placed on a body splint or a back board. The cushion presents a substantially box-like structure extending over the top of the patient's head and along either side. Straps are positioned across the forehead and jaw of the patient.
U S. Pat. No. 4,297,994 issued Nov. 3, 1981 to Beeshaw illustrates a similar device in which a pair of relatively large rectangular blocks are positioned on either side of the patient's head extending from adjacent the shoulder to above the top of the head. A strap extending across the top of the head connects the two blocks. Immobilization straps may then be placed running across the patient's forehead and jaw extending from the outside surfaces of the square blocks.
U.S. Pat. No. 4,528,981 issued Jul. 16, 1985, to Behar illustrates a cervical immobilization device comprising a pair of cylindrical support rolls one extending on either side of the head, the axis of the roll extending substantially parallel to the spine. Straps extending from each roll cross over the patient's forehead and jaw to maintain the location of the head and to stabilize against movement.
There have also been a number of proposals for use of relatively cheap, reasonably disposable supports made from a single piece of material such as corrugated material, sheet plastic, cardboard or other material which is light in weight and which can be folded for storage and use. One example of this type of device is illustrated in U.S. Pat. No. 4,928,711 issued May 29, 1990 to Williams. The Williams device includes a pair of laterally extending side support panels. Each of the side panels includes an inner panel and an outer panel with the inner panel being conformable to a shape necessary to support the head of the patient. The inner panel also includes an opening which divides a portion of that inner panel into a pair of spaced support members which extend laterally from the base. The outer panel has inner and outer edges and is attached by a hinge to the inner panel such that it is foldable relative to the inner panel to provide a substantially rigid brace for securing the inner panel in the desired immobilizing position. The outer panel also includes a cut out portion for providing substantial access to the opening of the inner panel when in the braced configuration.
While many of the prior devices are effective to stabilize the head and cervical region of the spine against movement during transport the head supporting structure does not allow for assessment by medical staff. Typically, when there is injury in the region of the head or in the region of the neck it is desirable to have access to the ear so as to be able to view bleeding from the ear or discharge from the ear and the like which may be useful in assessing medical conditions. With prior art structures that involve rolls, blocks or panels that extend along the side of the head it becomes impossible to assess for head injuries and the like without removing the supporting structure. Thus, before any detailed assessment can be carried out the head immobilizing structure must be removed and some different structure installed in its place during that initial assessment. It is also desirable in many instances to be able to use the standard forms of cervical collar to provide support for the patient's cervical region while also immobilizing the head. It is often desirable to provide the cervical collar rather than simply immobilizing the head. Thus it is desirable that a head immobilizing structure permit the use of a cervical collar.
One of the major areas which devices as referred to above and many others of this type do not address is the question of the elevation of the head. Different body configurations will result in different alignments of the spine when the patient is placed on a hard supporting surface such as a back board or stretcher. Depending upon the configuration of the patient's back, the head may in fact tip backward thus bending the cervical spine backward before the head contacts the surface of the backboard. In these situations the paramedical staff must insert pillows, cushions or other supports underneath the back of the head in an attempt to ensure that the spine is aligned in its natural alignment when viewed horizontally. The placing of pillows, cushions or supports under the back of the head then is a further step requiring handling of the head by the paramedical staff and may interfere with the proportions, angles and other support structure of the head immobilizing device.
SUMMARY OF THE INVENTION
According to the present invention a head immobilizing device to restrain and support the human skull in conjunction with a patient support surface such as a back board or stretcher or the like comprises complimentary left and right support blocks. Each support block includes a base surface and a concave skull supporting surface. The concave skull supporting surface of each block has first and second lobes. The first lobe extends generally vertically upwardly while the second lobe extends generally horizontally and forwardly. There is a L-shaped perimeter edge to the skull supporting surface lying between the first and second lobes. The skull supporting surfaces of the complimentary left and right blocks diverge upwardly and outwardly away from one another so that in use a skull may be supported between the blocks. In order to immobilize the head of the patient the complimentary support blocks are moved from lateral positions one on either side of the head toward the head so that the skull support surface of each block contacts the skull. As the surfaces diverge outwardly and upwardly lateral movement of the blocks toward each other will act as a wedging force to lift the skull vertically upwardly so that the cervical region of the patient may be aligned and the height of the head selected as desired by the paramedical or medical staff. The first generally vertical lobe extends upwardly behind the ear of the patient while the second lobe extends generally horizontally forwardly below the ear of the patient. The L-shaped edge of the skull supporting surface is adapted to accommodate the human ear so that the ear and side of the head of the patient remains available for medical assessment.
The wedging action of the complimentary left and right blocks acting in conjunction with the skull supporting surface eliminates any side to side movement of the head and eliminates any rolling of the head while supporting the head in the vertical direction. If it is desired to prevent lifting of the head by the patient then a strap may be placed across the forehead of the patient with the strap being affixed either to the complimentary left and right blocks or to the patient support surface.
In a particularly inexpensive version which may involve disposable blocks, the complimentary left and right blocks may be manufactured from material such as expanded polystyrene foam. A base surface of each such block may be equipped with an adhesive and advantageously with a small support boss or ribs. The left and right blocks may be slid along the patient support surface along the bosses or ribs until the head is properly captured between the blocks and supported. The blocks may then be pressed vertically downwardly compressing the ribs or bosses so that the adhesive then contacts the patient support surface thereby quickly and easily immobilizing the head. This procedure can be accomplished easily by the paramedic using the two hands to support and position the head both from a side to side and up and down position as desired. Fixation occurs simply by pressing the blocks into the board and contacting the adhesive with the board.
In a more permanent form the device may include a support beam with the complimentary left and right blocks being laterally slidable along the support beam. Advantageously the support beam includes a ratchet or track system and each of the support blocks includes a pawl. With this type of set up the support beam is either in place on the stretcher before the patient or the beam is slid beneath the patient's head and the two blocks are then slide laterally toward the patient's head to similarly position the head as desired. With the left and right support blocks holding the head each pawl is released to hold the blocks in position. Such a device can be manufactured of any relatively permanent equipment that is suitable for re-use and thus may require sterilization. Such equipment can be used in a medical facility and ideally is manufactured from materials that enable use within appropriate diagnostic equipment, such as x-ray equipment, CT scanners and the like.
DETAILED DESCRIPTION OF THE INVENTION
A better and more complete understanding of the invention will be had from reference to the following drawings which illustrate by way of example a preferred embodiment of the invention and in which:
FIG. 1 illustrates a device in accordance with the invention viewed in position on a back board with the patient's head indicated in stippled lines to indicate orientation and location of the support blocks;
FIG. 2 illustrates one of the blocks of FIG. 1 showing the patient skull supporting surface;
FIG. 3 illustrates the block of FIG. 2 when viewed from the face opposite the face shown in FIG. 2;
FIG. 4 illustrates the lowermost surface of the block illustrated in FIGS. 2 and 3;
FIG. 5 is an expanded scale view of the encircled portion of FIG. 2, labelled 5;
FIG. 6 is a view of the block and board of FIG. 5 with the block having been adhered to the patient support board;
FIG. 7 is a view of an alternate embodiment of the invention similar to FIG. 1;
FIG. 8 is a cross-section through the support track and the bottom portion of the block of FIG. 7, and
FIG. 9 is a top view of the embodiment of FIG. 7 illustrating the patient's head in stippled lines.
FIG. 1 shows the complimentary left and right blocks 12 and 14. The two blocks are essentially mirror images of each other. As shown in FIG. 1 the two blocks are arranged in use to lie facing each other. Each block comprises a skull supporting surface 16 which is shown in FIGS. 1 and 2 and a base 18. Each of the skull supporting surfaces 16 is a concave surface as shown in FIGS. 1 and 2. The curvature of the concave surface is a compound curvature which is selected to generally conform with the curvature of the average skull. This will be discussed in greater detail below. Although each skull supporting surface 16 is a compound curve the general orientation of the surface is indicated in FIG. 1 by the planar element 19. The angle of the element 19 to the horizontal is approximately 60°. Thus the included angle between the skull supporting surfaces of the left and right blocks is approximately 120°.
It will be appreciated from FIG. 1 that as the complimentary blocks 12 and 14 are moved laterally toward the skull of the patient, the surfaces 16 act as a wedge to lift the skull and position the skull at the desired height. Preferably the general angle of the plane 19 to the horizontal is between 45° and 75° and most preferably is approximately 60°. This gives a good balance of the wedge action to accurately position the height while at the same time supporting the skull regardless of where on the curve the skull contacts the skull supporting surface.
FIG. 2 illustrates the skull supporting surface 16. It will be noted from review of FIG. 2 that the skull supporting surface 16 commences above the base surface 18. As the complimentary support blocks will not be brought into contact with each other there will be some vertical displacement of the point at which the skull contacts the skull supporting surface above the base surface 18. The concave curve to the skull supporting surface 16 is slightly larger than the curve of the average human skull. Thus the area of contact is relatively broad, sufficient to be comfortable and not point contact on the skull while at the same time allowing for different areas of contact on the curve between the skull supporting surface. The precise area where the skull contacts the skull contacting surface will vary depending upon the desired height location of the head above the patient support surface as well as the actual configuration of the curve of the patient's skull. However, the area of contact is significant and thus regardless of where on the surface the skull is contacted the skull cannot move from side to side once the complimentary blocks bear against either side of the skull.
Again from review of FIG. 2 it will be observed that the skull supporting surface 16 includes first lobe 30 and second lobe 32. The first lobe 30 extends generally vertically and upwardly. The second lobe 32 extends generally horizontally and forwardly. The skull supporting surface 16 includes a L-shaped perimeter edge portion 34 between the first and second lobes 30 and 32. The L-shaped perimeter edge is adapted to surround the ear of the patient so that the entire ear area is accessible for medical evaluation and treatment. FIG. 3 illustrates the same L-shaped perimeter 34 from the surface of the block which is distal to the skull and further illustrates that the ear of the patient is free for assessment when the blocks are in place immobilizing the skull.
The complimentary blocks as described above serve to fully support the head once the blocks have been positioned and fixed relative to the patient support surface 20. Several different approaches may be taken to locating the blocks with respect to the patient support surface 20. Two particularly advantageous systems however involve firstly disposable blocks which can be used by paramedical staff in ambulances and the like and secondly a much more permanent fixation system which can be used in hospitals for transferring patients to medical assessment equipment such as x-ray equipment, CT scans and the like.
One of the prime considerations in head immobilization equipment to be carried by ambulances and the like is the need to have disposable, lightweight and relatively inexpensive equipment. Particularly in respect of head injuries, it is desirable that once the patient's head has been immobilized on a back support board 20 that the head immobilizing device be left with the patient if at all possible and for as long as possible. Put another way, it is best that the patient be fully assessed without the need to remove the head immobilizing structure. This means in turn that the head immobilizing structured utilized by ambulance attendants and the like should be disposable or intended as a single use device. For these applications it is considered that a particularly advantageous form the device involves the complimentary left and right skull supporting blocks being manufactured from material such as expanded polystyrene foam. Such material is particularly cheap but maintains sufficient rigidity to position and support the head in the manner as discussed above. With disposable blocks of this type it then becomes necessary to provide a simple, cost effective, but strong method of positioning the blocks relative to the patient support surface 20.
FIG. 4 illustrates the base surface of a disposable block 12. Extending along the bottom of the base surface 18 there are two ribs 40. The two ribs 40 are also illustrated in FIG. 3. The ribs 40 extend laterally along the base surface of the block 12. Many back boards 20 used for supporting patients include a variety of holes for access, tie downs and lightweight considerations and the like. The ribs 40 advantageously extend laterally the length of the base surface 18 so as to span any holes that may be present in the back board. The ribs are outstanding from the surface 18. If a back board is used which does not have any holes, it may be possible to use circular bosses, buttons or the like outstanding from the surface 18 to provide the spacing function which is discussed hereinafter. With reference to FIG. 4 it will be noted that the base surface 18 of the support block 12 is covered with an adhesive 42. The adhesive 42 may be a pressure sensitive adhesive and is used to affix the support block to the patient support surface 20. A cross-sectional view on an enlarged scale of one of the ribs 40 is illustrated in FIG. 5. Most preferably the rib 40 is accompanied on either side by a relieved channel 44 which extends below the surface 18.
The purpose of the rib 40 is to space the adhesive 42 from the surface of the patient support surface 20 until it is desired to affix the support block to the patient support surface. Thus, the support blocks are supported on the patient support surface by the ribs 40 during the initial positioning step. When the support blocks have been positioned to appropriately support and immobilize the skull then vertical downward pressure is placed on the support blocks 12 and 14. The downward pressure is sufficient to compress the ribs 40. In order to assist in the compression of the rib 40, the channels 44 provide a void area into which the compressed rib 40 may flow under compression. The compressing of the rib 40 thus brings the pressure sensitive adhesive 42 into contact with the surface of the patient supporting device 20 and the support block is then fixed to the patient supporting device.
In many cases it may be desirable that the patient does not attempt to lift his or her head. In order to guard against this type of motion a strap 22 may be placed over the forehead of the patient and affixed to the patient supporting surface 20. The strap 22 may be affixed directly to the patient supporting surface 20 such as by adhesive, hook and loop fasteners or the like or the strap 22 may be affixed to the patient supporting surface 20 through the intermediary of the left and right support blocks. It is considered that it is most preferable to affix the strap directly to the patient support surface 20.
A reusable form of the device is illustrated in FIGS. 6, 7 and 8. In this embodiment the complimentary left and right skull supporting blocks 12 and 14 are essentially similar to those as discussed above. However, the material from which the blocks are made may differ considerably in view of the fact that the device is to be reused. Preferably the material is material which can be sterilized and which does not adversely effect various medical assessment tools such as x-ray equipment, CT scanners and the like. Ideally the entire device may be made from polyethylene which meets all of these requirements.
The device illustrated in FIG. 6 comprises complimentary skull support blocks 12 and 14 and a support beam 60.
The interrelation between the support beam 60 and the block 12 is more clearly shown in FIGS. 7, 8 and 9.
The support beam 60 comprises a track 62. The track 62 is a T-shaped projection in the upper surface of the support beam 60. With this configuration the base surface of the skull support block 12 comprises downwardly and inwardly projecting skirts 64 and 66. The interrelation of the track 62 and the skirts 64 and 66 prevents any vertical movement between the support beam 60 and the support block 12. In order to load the support block on the support beam 60, the support block must be slid from one end onto the support beam 60.
The upper surface of the track 62 advantageously comprises a plurality of serrations or teeth 70. These are shown in larger scale in FIG. 7. The teeth 80 are provided with a sloped surface 82 and a substantially vertical surface 84. The sloped surface 82 slopes upwardly and inwardly toward the middle of the support beam 60. That is to say, the sloped surface extends inwardly from each end. The teeth 80 inter-react with a pawl 86 carried by the support blocks 12 and 14. The pawl 86 may be in the form of a pin or in the form of a substantially rectangular tongue. Advantageously the pawl 86 projects upwardly through the outer surface of the blocks 12 and 14 and is spring loaded by means of a spring 88 biassing the pawl downwardly. With this structure the support blocks 12 and 14 may be loaded onto the support beam 60 by aligning the skirt 64, 66 with the track 62. As the blocks are slid inwardly towards the centre of the track, the pawl will ride up the sloped surfaces 82 and thus the support blocks can be slid freely and easily with one hand toward each other, toward the patient's skull. When it is desired to remove the skull supporting blocks 12 and 14 from adjacent the patient's skull, then the pawl 86 is lifted by inserting a finger and raising the pawl against the spring 88. The support blocks can then be slid outwardly as the pawl no longer engages the vertical surface 84 against which it was locked for outward motion.
As shown in FIGS. 7 and 9 a strap 90 may be used to further secure a patient's head against vertical motion. The strap 90 may be joined to the skull support blocks 12 and 14 by means of buckles or by hook and loop fasteners or the like. In this case the support blocks 12 and 14 are securely vertically affixed to the support beam 60 and thus the strap 90 advantageously extends only between the support blocks 12 and 14 and does not need to extend down to the support beam 60 or the patient support surface 20 on which the patient is lying.
The support beam 60 may be fastened to the patient support surface 20 by any convenient means. If the support beam is to be used with a typical back board then the support beam may include a pivoted latch 92 of either end which can grasp the edge of the back board. Where the beam is used with a stretcher, straps with buckles or other closures may be utilized.
The colours red and green are widely recognized and internationally accepted as indications of left and right sides. The colours are used in connection with ships and aircraft to identify such vessels to other vessels and as navigation aids. In the first embodiment of the device described above it was pointed out that the devices are advantageously maintained by ambulance attendants and the like for quick ready use. Because the devices are in the form of left and right complimentary blocks it is likely that ambulance attendants will wish to carry more than one set of such blocks. In order to assist in the quick and ready utilization there is an advantage in coding the left and right blocks so that they can be instantly recognized by the ambulance attendant. For this reason it is suggested that some or at least a portion of the block which is to contact the left side of the patient's skull be coloured red while a similar portion of the right side block should be coloured green. The colour indication may be in the form of complete colouration of the whole surface, a patch of colour, colour stripes or the like. In any case this will help to assist the ambulance attendant or the like, using the blocks to ensure that he has a pair of blocks and which block should be grasped by which hand in order to immobilize the patient's skull. The colour coding is less important in the more permanent version discussed in association with FIGS. 7, 8 and 9. However, even in these cases it may be advantageous to mark the left and right extremities of the device. This may include marking of the blocks themselves or by markings or the end of the support track so that the support track may be positioned correctly. While this should be obvious to the operator within a medical facility, colour marking of this type may be advantageous to ensure that the blocks are brought into contact with the skull with the orientation as illustrated in the figures herein.
While generally speaking a strap extending across the forehead region may be used as shown in FIGS. 1 and 9, a strap cannot be placed across the forehead where there is reason to suspect there has been damage to the skull in this area. Accordingly, when there is suspicion of a depressed fracture of the skull in the forehead region a strap should not be applied to that area of potential injury. In this case an immobilizing strap may be attached to the patient's head by extending around an obviously uninjured area. This may mean using these straps between the patient's jaw and the left and right blocks or the nose or cheek bones or the like, all as may be available without increasing damage which the patient may have already suffered. In such circumstances, the left and right blocks as disclosed herein provide particularly suitable anchor points for immobilization when the patient's forehead does not appear to be an acceptable choice for strap location.
From review of this description it will observed that a simple, effective device has been disclosed which serves to both locate the patient's skull with respect to side to side motion while at the same time providing a means to vertically position the skull in the most advantageous position. Quick and easy adjustment of the skull support blocks may be achieved. While the device is in place supporting and immobilizing the skull from any further movement, the head and ear remains available for further medical assessment and the patient can be placed in a standard cervical collar. It will be appreciated that many variations and changes may be made to the structure as disclosed herein without departing from the scope of the invention as defined in the appended claims. | A device for immobilizing the head to prevent further injuries such as neck injuries comprises left and right complimentary blocks. Each block has a skull supporting surface. The blocks contact the skull with the skull supporting surfaces diverging outwardly and upwardly to provide a wedging action to immobilize the skull against left and right movement as well as to position the height of the skull so that alignment of the neck is achieved. The skull supporting surface surrounds but does not cover the ear so that assessment may be made easily. The left and right blocks may be disposable for one time use or permanently mounted on a carrier for reuse. | 0 |
PRIORITY CLAIM
[0001] This application is a continuation application of U.S. patent application Ser. No. 11/975,148, filed on Oct. 18, 2007, now U.S. Pat. No. 7,883,227, which is a divisional application of U.S. patent application Ser. No. 09/755,775, filed on Jan. 4, 2001, now U.S. Pat. No. 6,773,128, which is a divisional application of U.S. patent application Ser. No. 09/139,927, filed Aug. 26, 1998, now U.S. Pat. No. 6,199,996, which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to illumination of keyboards, keypads, and other data entry devices.
[0004] 2. Description of the Relevant Art
[0005] Keyboards, keypads, mouses, and other data entry devices (hereinafter referred to generally as keyboards) are used in a variety of applications for entry of alphanumeric and other types of data into a machine such as a calculator or computer. Keyboards have been developed that are light weight, low in cost, and relatively easy to manufacture. However, difficulty has been encountered in the development of illuminated keyboards that are light weight, low in cost and easy to manufacture. For example, methods have been developed which require placement of a light source below and in proximity of each key of the keyboard, and each of these light sources must be connected to a power supply, rendering the manufacture of such a keyboard difficult and expensive. Another method for illuminating a keyboard requires a single light source that provides light to each key by means of optical light paths. The optical light paths are difficult to construct in order to illuminate the keys uniformly and efficiently. These methods have the disadvantage of requiring considerable power for illumination, an important consideration for laptop computers and calculators operating under battery power. Moreover, all of these methods are unsuitable for many of the new keyboards that have been developed which are not flat, such as ergonomic keyboards that arc upward and outward from a horizontal surface. More generally, none of the methods of the prior art are readily adaptable to existing keyboard manufacturing processes. Thus, the manufacturing process for manufacturing ordinary non-illuminated keyboards cannot readily and easily be adapted to the manufacture of illuminated keyboards.
SUMMARY OF THE INVENTION
[0006] An object of the present invention is to provide methods for manufacture of illuminated keyboards that can easily be adapted and incorporated into the manufacture processes that exist for non-illuminated keyboards.
[0007] Another object of the present invention is to provide methods for manufacture of illuminated keyboards that may be applied to keyboards of any shape, including ergonomic keyboards.
[0008] Another object of the present invention is to provide uniform illumination of the keys in a manner that does not require implementation of complex optical pathways or separate light sources for each key, and further provides illumination that consumes very low power.
[0009] Yet another object of the present invention is to provide illumination that possesses controllable visual functionality as well as aesthetic attributes.
[0010] According to one aspect of the present invention a flexible, thin, low power, inexpensive, luminescent sheet is adhered to the surface of the key board well plate of a keyboard. The key board well plate is manufactured in any manner and shape as required by the manufacturing process typically used and as required by the shape of the keyboard to be produced. The luminescent sheet may be adhered to the upper surface of the keyboard well plate. Alternatively, the luminescent sheet may be placed between the keyboard well plate and the circuit board of the keyboard. In this configuration the keyboard well plate is made from any optically transmissive material possessing sufficient rigidity to function as a key board well plate. Such materials, such as plexi-glass and other moldable plastics are well known in the art. The keys are also manufactured as required by the manufacturing process ordinarily used, except that the keys are made from an optically transmissive material, and may further contain phosphorescent material that glows residually during and after illumination. The luminescent sheet may be easily connected to a battery or any available power source, including the source that provides power to the keyboard itself. Further, the luminescent sheet may be connected to a device such as a rheostat to allow the user to vary the intensity of illumination. Also, a photo cell may be connected to the source of power of the luminescent sheet to cause the intensity of light from the sheet to automatically vary in response to the darkness of the environment in which the keyboard is used.
[0011] According to the present invention, luminescent sheets of different colors can be placed under different sections of keys to improve visual differentiation of key groups. Also, the optically transmissive keys can be tinted so that the same luminescent sheets will cause keys tinted by different colors to appear in different colors. Similarly, the top plate of the keyboard which is normally opaque can also be manufactured from an optically transmissive material so that the entire upper surface of the keyboard will be illuminated. The top plate may be tinted to provide visual contrast. Also, one luminescent sheet of one color can be applied to illuminate the top plate with a color that is different from the color of the luminescent sheet that illuminates the keys. All of these features may be combined to provide an illuminated keyboard that possesses controllable visual functionality and aesthetic attributes. Further, the methods of the present invention disclosed herein can be implemented by persons of ordinary skill in the art to convert existing keyboards into illuminated keyboards.
[0012] These and other features, aspects and advantages of the present invention will become apparent and better understood with reference to the following written description, attached drawings, and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] For a more complete understanding of the present invention, and the advantages thereof, the following description is made with reference to the accompanying drawings, in which:
[0014] FIG. 1 illustrates a construction of a typical keyboard.
[0015] FIG. 2 illustrates placement of a luminescent sheet below a well plate.
[0016] FIGS. 3 a , 3 b and 3 c illustrate construction and electrical connection of a typical luminescent sheet.
[0017] FIG. 4 illustrates an embodiment for illumination of a top plate.
[0018] FIG. 5 illustrates placement of a luminescent sheet above a well plate.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] A functional diagram of the construction of a typical keyboard is shown in FIG. 1 . Typically, a keyboard 5 is comprised of keypads 10 , keystems 11 , a keyboard top plate 20 , a keyboard well plate 30 , a circuit board 40 with key spring switches 13 and a key board bottom plate 50 . Typically all of these components are manufactured of opaque materials. Keystems 11 are inserted through holes 12 in keyboard well plate 30 . Holes 12 in keyboard well plate 30 are aligned with key spring switches 13 of circuit board 40 . Circuit board 40 is secured to key board bottom plate 50 . Key board top plate 20 fits over or otherwise attaches to key board bottom plate 50 , and thereby provides enclosure for the keyboard. Typically, keys are grouped in a keyboard according to function. For example, on a typical keyboard for typing words and data into a word processor, a set of alphabet keys, number keys, and other certain symbol keys are grouped together in a traditional typewriter key layout, herein referred to as the typewriter keys. Another separately grouped set of keys are the arrow keys which allow control of a cursor displayed on a video monitor. Function keys are separately grouped in a single line across the upper portion of the key board, etc. These separately grouped sets of keys will be referred to as key groups. Top plate 20 is designed so that when placed in position, the keypads 10 extend through top plate 20 while the areas between key groups are covered by surface 21 of top plate 20 .
[0020] A preferred embodiment of the present invention is illustrated in FIG. 2 . A flexible luminescent sheet 100 is adhered to the lower surface 32 of key board well plate 30 that faces the surface of circuit board 40 . Any suitable substance known in the art that is optically transmissive may be used to adhere luminescent sheet 100 to lower surface 32 . Alternatively, flexible luminescent sheet 100 may be placed between keyboard well plate 30 and circuit board 40 without the use of an adhering substance, if luminescent sheet 100 will be sufficiently compressed between keyboard well plate 30 and circuit board 40 to remain in place. Holes 112 are made in flexible luminescent sheet 100 to align with holes 12 in keyboard well plate 30 .
[0021] Luminescent sheet 100 is comprised of a commercially available electroluminescent (E-L) lamp. E-L lamps are solid state devices constructed of thin phosphor-coated plastic sheets with conductive surfaces. When a power source is applied to the conductive surfaces the phosphors illuminate and light is emitted from the entire surface. E-L lamps are thin, flexible and can be twisted, bent or formed into any shape. These lamps draw very little power and produce very little heat. A typical construction of luminescent sheet 100 is illustrated in FIG. 3A . Each conductive surface, metallized polyester film 131 and rear electrode 132 , is connected at an edge of sheet 100 by electric leads 105 . The upper conductive surface, metallized polyester film 131 , is an optically transmissive conductor. When leads 105 are connected to a power source 110 , the entire sheet illuminates with an intensity that is substantially uniform across the entire surface of sheet 100 . Luminescent sheets are commercially available in a variety of colors such as white, yellow, blue and green. They may be cut to order by the manufacturer, who will provide electrical tabs connected to the conductive surfaces for connection to an electrical power source. For example, flexible luminescent sheets may be obtained from SEG Corporation. SEG may be contacted through their Internet address: www.flashseg.com.
[0022] Flexible luminescent sheet 100 is connected through leads 105 to any convenient power source 110 , which may be a battery or the power source of keyboard 5 . The intensity of light from luminescent sheet 100 can be varied using an intensity control device 85 such as a rheostat in series with power source 110 , as illustrated in FIG. 3B . In addition, or in the alternative as shown in FIG. 3B , intensity may be controlled by providing a photosensitive device 90 , such as a photo-cell, and associated circuitry to control the intensity of luminescent sheet 100 in response to the intensity of light in the environment in which keyboard 5 is used. A variety of methods, devices, and circuitry for controlling the intensity of luminescent sheet 100 will readily be recognized by persons of ordinary skill in the art.
[0023] In this embodiment, keyboard well plate 30 is manufactured from an optically transmissive material. Any optically transmissive material that is sufficiently rigid to achieve the ordinary purposes of a keyboard well plate will suffice. Even a partially opaque optically transmissive material may be used as long as light of sufficient intensity is transmitted through keyboard well plate 30 to provide illumination visual to the user. Examples of materials that can be used for this purpose are plexiglass and other optically transmissive plastics. Other suitable materials will be known to persons of ordinary skill in the art. Similarly, keypads 10 and key stems 11 will be manufactured from an optically transmissive material, that is, materials that are at most only partially opaque and transmit sufficient light intensity to render the keys visual to the user. In addition, keypads 10 may comprise phosphors that will illuminate in response to the light received from luminescent sheet 100 . Thus, in this embodiment, luminescent sheet 100 transmits light through keyboard well plate 30 and through keypads 10 to provide visual illumination of keyboard 5 .
[0024] It may be desirable in some applications to provide a keyboard in which different keys, key groups and keyboard areas appear in different colors of illumination. A variety of methods can be implemented to achieve this according to the methods of the present invention. One method is to provide a plurality of luminescent sheets 100 of different colors under different portions of keyboard well plate 30 to cause different keys, keygroups and keyboard areas to be illuminated by different colors. Another method for providing keys of different colors is to tint the optically transmissive material from which the keys are made, so that when the keys are illuminated by a luminescent sheet 100 , the key color will be a composite of the light from the luminescent sheet and the tint of the keys. Also, the optically transmissive keys from which the keys are made may be mixed with phosphors of different colors when illuminated by luminescent sheet 100 .
[0025] A further variation of the method of illuminating a keyboard as described above is to manufacture top plate 20 of an optically transmissive material so that light from luminescent sheet 100 will transmit through the top plate to provide illumination of the top plate surface areas as well as the keys. Top plate 20 can be illuminated with a separate luminescent sheet 100 of a desired color by placing the separate luminescent sheet 100 under the surface area 22 of top plate 20 , such that the upper surface are 131 of luminescent sheet 100 is aligned with surface area 22 of top pate 20 , as illustrated in FIG. 4 . Top plate 20 can also be made of an optically transmissive material that is tinted with a desired color and, or, mixed with phosphors to provide luminescence in response to light received from luminescent sheet 100 .
[0026] In an alternative embodiment, luminescent sheet 100 can be adhered to the upper surface 31 of key board well plate 30 , as illustrated in FIG. 5 . In this configuration, keyboard well plate 40 can be made of any opaque material as is usually used, because light from luminescent sheet 100 illuminates the keys more directly without the necessity of transmission through key board well plate 30 . Also, the substance used to adhere luminescent sheet 100 to upper surface 31 of keyboard well plate 30 need not be an optically transmissive material in this configuration. In this configuration the keypads 10 are made of optically transmissive material, and top plate 20 can also be illuminated as described above.
[0027] An advantage of using a flexible luminescent sheet is the ability to provide illumination for non-traditional keyboards, such as ergonomic keyboards that are arcuate in shape in one or more spatial directions. Moreover, the methods of keyboard illumination disclosed herein can readily be adapted to any keyboard manufacturing process. This would enable a manufacturer of non-illuminated keyboards to quickly and inexpensively become a manufacturer of illuminated keyboards without developing an entirely new manufacturing process to accommodate specialized configurations. Further, the methods of the present invention disclosed herein can be implemented by any person of ordinary skill in the art to convert existing keyboards into illuminated keyboards. Moreover, the methods of the present invention disclosed herein can be applied to the manufacture of an illuminated mouse, by making the mouse buttons and exterior enclosure of an optically transmissive material and underlying these components with one or more luminescent sheets connected to a suitable power source.
[0028] While this invention has been described with reference to the foregoing preferred embodiments, the scope of the present invention is not limited by the foregoing written description. Rather, the scope of the present invention is defined by the following claims and equivalents thereof. | Methods are provided for adapting existing manufacturing processes for non-illuminated data-entry devices and mouses to the manufacture of illuminated data-entry devices. Luminescent sheets of one or more colors underlying optically transmissive device components provide illumination of the components visual to a user of the device. The optically transmissive components may be doped with phosphors or tinted to provide components that emit light of different colors. The intensity of illumination of the luminescent sheet may be controlled by the user and may vary in response to the background light of the environment. | 7 |
DETAILED DESCRIPTION OF THE INVENTION
This invention relates to an improvement in the process for producing the antineoplastic agent THIOTEPA; N,N',N"-triethylenethiophosphoramide. Heretofore, this compound has been prepared from a thiophosphoryl halide and ethyleneimine as set forth in the following reaction scheme: ##STR1## wherein X is chloro or bromo. This reaction is preferably carried out in an organic solvent such as benzene, diethyl ether, dioxane, and the like. It is also necessary to have present an acid acceptor which may be tertiary amine such as triethylamine, N-methylmorpholine or pyridine. The reaction can also be carried out in water or in a substantially aqueous solution in which case acid acceptors are also required to neutralize the hydrohalic acid formed. Under these circumstances, the acid acceptor may be an alkaline substance such as an alkali metal carbonate or bicarbonate. Isolation of the product from the organic solvent may be accomplished by filtration of the tertiary amine hydrohalide salt followed by evaporation of the organic solvent from the filtrate. When the compound is prepared in an aqueous medium, then it may be extracted from the aqueous solution by means of organic solvents. The reaction is generally carried out at a temperature within the range of 0° C. to about 60° C. At this temperature range, the reaction is usually complete within a period of 30 minutes to about 5-6 hours.
Ethyleneimine (aziridine) is a strongly alkaline liquid which polymerizes easily and has an intense odor of ammonia. The LD 50 orally in rats is only 15 mg./kg. of body of weight, and the F.D.A. has declared this substance a carcinogen. It is strongly irritating to eyes, skin and mucous membranes, and can also be a skin sensitizer. This extremely toxic chemical requires extra-ordinary precautions in use.
It has now been discovered that ethyleneimine can be generated in situ in the preparation of THIOTEPA, thus eliminating the external handling and introduction of this dangerously toxic chemical. The novel process of the present invention is carried out by first cyclizing a β-haloethylamine with an alkali metal hydroxide in aqueous medium. Suitable starting materials are 2-chloroethyamine, 2-bromoethylamine or 2-iodoethylamine, either as the free bases or the acid-addition salts thereof, while suitable bases are NaOH or KOH. This cyclization is carried out by adding an aqueous solution of the β-haloethylamine to an aqueous solution of NaOH or KOH over a period of time of from about 30 minutes to about 2 hours, all at a temperature of -10° C. to +10° C. When the addition is complete, the temperature of the mixture is adjusted to 30° C.-60° C. and the reaction mixture is stirred for 30-90 minutes. The temperature of the reaction mixture is then lowered to -10° to +10° C. and a stoichiometric excess of an alkali metal carbonate or bicarbonate is added, with stirring. This is followed by the addition of a stoichiometric amount of a thiophosphoryl halide, with stirring. The reaction mixture is then stirred for an additional 1-2 hours at -10° C. to +10° C. to complete the conversion to THIOTEPA followed by extraction of the product from the reaction mixture with a suitable water immiscible organic solvent such as benzene, diethyl ether, dioxane, and the like.
The invention will be described in greater detail in conjunction with the following specific example.
EXAMPLE 1
A reactor is charged with 7,700 to 8,300 parts of water, 7,600 to 8,600 parts of anhydrous potassium hydroxide are added and the solution is stirred and cooled to -10° C. to +10° C. While agitating, a solution of 10,400 to 11,400 parts of 2-bromoethylamine hydrobromide in 5,200 to 5,700 parts of water is charged to the reactor over 30 to 90 minutes, while maintaining the temperature at -10° C. to +10° C. When the addition is complete, the temperature is adjusted to 40° C. to 50° C. and the mixture is stirred for 40 to 70 minutes. The temperature is then lowered to -10° C. to +10° C. and 5,000 to 5,700 parts of anhydrous potassium carbonate are added with stirring. The ethylenimine thus generated in situ is further reacted with phosphorus sulfochloride to produce the desired THIOTEPA. | This disclosure describes an improved process for preparing N,N', N"-triethylenethiophosphoramide by the in situ generation of ethyleneimine. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation of the U.S. patent application Ser. No. 11/533,102, entitled “METHOD OF MANAGING STORAGE AND RETRIEVAL OF DATA OBJECTS,” which is hereby incorporated herein by reference in its entirety and for all purposes.
BACKGROUND
[0002] Computer systems generally include one or more processors interfaced to a temporary data storage device such as a memory device and one or more persistent data storage devices such as disk drives. Each disk drive generally has an associated disk controller. Data is transferred from the disk drives to the disk controller and is then transferred to the memory device over a communications bus or similar. In many computer applications, the speed at which data can be accessed on the disk drives is a limiter to performance.
[0003] Data compression has the capability to reduce the size of data and increase the speeds with which data can be written to and read from the disk drives. A sequential access device does not have directly addressable storage and hence it is possible to use compression to both increase performance and reduce the size of the data on media. Since sequential devices are not directly addressable, the compression module is free to redefine the format of data on media and can add compression headers in which to store useful information that will be needed when the data is uncompressed. In this way, compression for sequential access storage is able to be transparent to the application.
[0004] It is more difficult to compress data for random access devices in a manner that is transparent to the application. Compression with these systems having addressable storage requires a virtualization layer in the compression module that allows application addresses to be translated to device addresses. The virtualization also permits a compression layer to add useful metadata to the compressed objects. Using this method, a compression module can both produce capacity and increase performance for data transfer.
[0005] In certain applications, it is desirable to have a compression module for random access addressable storage that operates without a complex compression module that performs virtual address translation, garbage collection and optimal packing. In some of these applications, it is not necessary to conserve storage capacity but merely to reduce the time to write and/or read data to or from media such as disk drives. An example of a device that would benefit from write time reduction are memory devices that have write data rates orders of magnitude slower than read data rates.
SUMMARY
[0006] Described below are methods of managing retrieval of data objects from a storage device and methods of managing storage of data objects in a storage device.
[0007] One technique described below involving managing storage of a data object in a storage device first receives the data object (A) to store in the storage device, the data object having an indicator bit pattern (P). Successive compression data transformations or algorithms are applied to data object A to obtain respective corresponding compressed data objects. The compressed data object that has the shortest length with respect to the remaining compressed data objects is then selected and compression information (I) is generated that is associated with the compression data transformation used to generate the selected data object (C). A threshold value T is calculated at least partly from the length of compression information I. If the selected compression data transformation has the effect of reducing the bit size of the data object A by a threshold value T, then an indicator bit pattern of data object C is set to indicate that the object has been compressed, and compression information I is added to the data object C. The data object C is then written to the storage device. Otherwise, if the compression algorithm does not result in the required threshold reduction, then the indicator bit pattern of data object A is reset to indicate that the object has not been compressed and the uncompressed data object A is written to the storage device.
[0008] Another technique described below involves managing storage of data objects in a storage device. A data object (A) is received to store in the storage device, the data object having an indicator bit pattern. A data transformation is applied to data object A to generate compressed data object (C). A threshold value T is calculated. If length (C)+T≧length (A), then the indicator bit pattern of data object A is reset and the data object A is written to the storage device. If length (C)+T<length (A), then the indicator bit pattern of data object C is set and the data object C to the storage device.
[0009] Another technique described below involves managing storage of a data object in a storage device. The method involves receiving the data object (A) to store in the storage device. Successive compression data transformations are applied to data object A to obtain respective corresponding compressed data objects. One of the compressed data objects is selected, such that the selected compressed data object (C) has the shortest length with respect to the remaining compressed data objects. Compression information (I) is generated associated with the compression data transformation used to generate data object C. A threshold value T is calculated at least partly from the length of compression information I. If length (C)+T≧length (A), then the data object A is written to the storage device. If length (C)+T<length (A), then an indicator bit pattern (P) is incorporated into data object C, compression information I is incorporated into data object C, and data object C is then written to the storage device.
[0010] Yet another technique described below involves managing storage of a data object in a storage device. The method involves receiving the data object (A) to store in the storage device. A compression data transformation is applied to data object A to obtain a compressed data object (C). A threshold value T is calculated. If length (C)+T≧length (A), then the data object A is written to the storage device. If length (C)+T<length (A), then an indicator bit pattern (P) is incorporated into data object C and data object C is written to the storage device.
[0011] Further techniques described below cover retrieving data objects from a storage device.
[0012] Also described are systems and computer programs for managing storage and retrieval of data objects.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a block diagram of a computer system in which the techniques described below are implemented.
[0014] FIG. 2 is a flow chart of one technique for writing a data object to a storage device.
[0015] FIG. 3 is a flow chart of another technique for writing a data object to a storage device.
[0016] FIG. 4 is a flow chart of one technique for retrieving a data object from a storage device that has been stored by the techniques of FIG. 2 or 3 .
[0017] FIG. 5 is a flow chart of another technique for retrieving a data object from a storage device that has been stored by the technique of FIG. 2 or 3 .
[0018] FIG. 6 is a diagram of data objects handled by the technique of FIG. 2 .
[0019] FIG. 7 is a diagram of data objects handled by the technique of FIG. 3 .
[0020] FIG. 8 is a block diagram of an exemplary large computer system in which the techniques described below are implemented.
DETAILED DESCRIPTION
[0021] FIG. 1 shows a computer system 100 suitable for implementation of a method of managing storage and retrieval of data objects. The system 100 includes one or more processors 105 that receive data and program instructions from a temporary data storage device, such as a memory device 110 , over a communications bus 115 . A memory controller 120 governs the flow of data into and out of the memory device 110 . The system 100 also includes one or more persistent data storage devices, such as disk drives 125 1 and 125 2 that store chunks of data or data objects in a manner prescribed by one or more disk controllers 130 . One or more input devices 135 , such as a mouse and a keyboard, and output devices 140 , such as a monitor and a printer, allow the computer system to interact with a human user and with other computers.
[0022] The disk controller 130 receives requests from the memory controller 120 to store data objects on the disk drives 125 and to retrieve data objects from the disk drives. Repeated requests for data to be transferred to or from the disk drives has the potential to create a bottleneck between the disk drives 125 and the disk controller(s) 130 . Such a bottleneck can affect performance of the computer system 100 due to the delay in transmitting or transferring data objects from the disk drives to the disk controller for subsequent transfer over the communications bus 115 .
[0023] The techniques described below involve reducing the amount of data that is written to the disk drives 125 by the disk controller 130 and reducing the amount of data retrieved from the disk drives 125 by the disk controller 130 . The technique is best implemented in an application-specific integrated circuit (ASIC) 145 that is configured to selectively compress data objects to be written to the disk drives 125 and to uncompress data objects received from the disk drives 125 that have been compressed. In one form, the ASIC 145 is associated with a disk controller 130 .
[0024] FIG. 2 shows an example of one technique for writing a data object to a storage device with the intention of reducing data traffic between the disk drives and the disk controller. The disk controller 130 first receives an instruction from an application to write a data object to disk drives 125 (step 200 ). The application that has transmitted the data object to the disk controller dedicates to the compression function a single bit within each data object at a known offset from the start of the data object. This single bit functions as an indicator bit pattern. As will be apparent from the description below, this indicator bit pattern indicates whether or not a data object subsequently retrieved from the disk drives 125 has been compressed.
[0025] The ASIC 145 has available to it a plurality of compression data transformations or algorithms. These compression data transformations include Huffman encoding and run length encoding, and any other compression techniques suitable for the data in the data objects. These compression data transformations are applied successively to the data object received by the disk controller (step 205 ). This process generates a plurality of compressed data objects, each of the data objects generated by a different compression data transformation.
[0026] If a compression algorithm is applied to a data set, it is not guaranteed that the compression will reduce the size of the data set. It is possible in some cases for the data set to remain the same size or even to increase in size. One of the generated compressed data objects is selected such that the selected compressed data object has the shortest length with respect to the remaining compressed data objects (step 210 ). In other words, the data object of shortest length is selected from the store of generated compressed data objects.
[0027] The technique in one form generates compression information (I). This compression information represents metadata, one purpose of which is to identify the compression algorithm used to generate the selected compressed data object. This compression information in one form simply consists of a compression data transformation identifier to identify the compression data transformation used to generate the shortest compressed data object. The compression information alternatively also includes a symbol table for use by the compression data transformation and the length in bits of the compressed data object.
[0028] Having identified the most effective compression algorithm and generated compression information associated with the compression algorithm, the technique then calculates a threshold value T at least partly from the length of compression information I. In one form of the technique, this threshold value T is the length in bits of the compression information plus 1.
[0029] It is desirable to store the compression information with each data object that has been compressed. The compression information I represents an overhead. To be effective, the selected compression algorithm must reduce the size of the data object by an amount such that the length of the compressed object once the threshold value T is added to it remains smaller in size than the original uncompressed data object. If so, the indicator bit pattern of the compressed data object is then set, for example by setting the value of the bit in the indicator bit pattern position to “1” and the data object C is written to the disk drives 125 together with compression information I. Viewing this process another way, the compression information I is incorporated into the data object C and the combined data is written to the disk drives 125 . Compression information I in one form is simply concatenated to data object C although the compression information in other forms is inserted in other positions within data object C.
[0030] Referring to FIG. 2 , the effectiveness of the selected compression algorithm is tested (step 215 ). If there are sufficient gains in reducing the size of the data object as measured by the test described above, then the indicator pattern in the compressed object is set to indicate that the data object has been compressed (step 220 ), the compression information I is incorporated into the compressed object (step 225 ) and the compressed object is written to the disk drives (step 230 ).
[0031] Alternatively, if there is not sufficient advantage in applying the most effective compression algorithm, then the indicator bit in the original data object is then reset or cleared to the value “0” to indicate that the data object has not been compressed (step 235 ). The uncompressed data object is then written to the disk drives (step 240 ).
[0032] FIG. 3 shows an example of another technique for writing a data object to a storage device with the intention of reducing the data traffic between the disk drives and the disk controller. The disk controller receives an instruction from an application to write a data object to the disk drives (step 300 ). The application that has transmitted the data object to the disk controller guarantees that a certain pattern will never occur in a particular set of bits at known offsets within each data object. The set of bits are otherwise usable by the application. This collection of bits functions as an indicator bit pattern. In common with the technique described above with reference to FIG. 2 , the indicator bit pattern indicates whether or not a data object subsequently retrieved from the disk drives has been compressed.
[0033] As described above, the ASIC has available to it a plurality of compression data transformations or algorithms. These compression data transformations are applied successively to the data object received by the disk controller (step 305 ). This process generates a plurality of compressed data objects, each of the data objects generated by a different compression data transformation. The technique then selects the most effective compression algorithm by selecting the data object of the shortest length from the store of generated compressed data objects (step 310 ) as described above.
[0034] The technique in one form also generates compression information (I) that identifies the compression data transformation used to generate the shortest compressed data object, a symbol table for use by the compression data transformation, and/or the length in bits of the compressed data object.
[0035] Having identified the most effective compression algorithm and generated compression information associated with the compression algorithm, the technique then calculates a threshold T at least partly from the length of compression information I. In one form of the technique, this threshold value will be the sum of the length of the compression information (I) and the length of the indicator bit pattern (P). As described above, it is desirable to store the compression information with each data object that has been compressed. The selected compression algorithm must reduce the size of the data object by an amount such that the length of the compressed object once the threshold number of bits is added to it, remains smaller in size than the original uncompressed data object.
[0036] If the sum of the length of the compressed object, the length of the threshold T and the length of the indicator bit pattern P is less than the length of the uncompressed object (step 315 ), then the indicator bit pattern P is incorporated into the compressed data object (step 320 ), the compression information I is incorporated into the compressed data object (step 325 ), and the combined data is written to the disk drives (step 330 ).
[0037] Alternatively, if there is not sufficient advantage in applying the most effective compression algorithm, then the uncompressed data object is written to the disk drives (step 335 ).
[0038] FIG. 4 and FIG. 5 show examples of techniques for retrieving data objects from a storage device that have been stored by the techniques of FIG. 2 or 3 above. The technique described in FIG. 4 is best suited to systems where it is not efficient to retrieve data objects piece-wise, and FIG. 5 is better suited to systems where there is no additional overhead associated with reading a data object piece-wise.
[0039] In FIG. 4 a disk controller first receives an instruction from an application to retrieve a data object from the disk drives (step 400 ). The entire data object is then retrieved from the disk drives (step 405 ).
[0040] The indicator bit pattern of the retrieved data object is then examined (step 410 ). If the indicator bit pattern is set, this indicates that the retrieved data object has been compressed and that a decompression algorithm must be applied to the data object. If the data object has been stored using the technique of FIG. 2 , this indicator bit pattern will be a single bit at a known offset within the data object. If this single bit has the value “1”, then this indicates that the data object has been compressed. Alternatively, if the data object has been stored by the technique of FIG. 3 , the value of certain bits within the data object at known offsets will indicate that the data object has been compressed.
[0041] If the data object has not been compressed, the retrieved data object is simply returned to the requestor (step 415 ).
[0042] Alternatively, if the data object has been compressed, compression information (I) is obtained or retrieved from the compressed object (step 420 ). The compression information I specifies the decompression data transformation selected from a set of decompression data transformations to be applied to the data object and any information needed for decompression such as symbol tables. The specified decompression algorithm is applied to the retrieved data object (step 425 ) and the uncompressed data object is returned to the requestor (step 430 ).
[0043] In FIG. 5 , the technique receives a request to retrieve a data object (step 500 ). As described above, the technique of FIG. 5 is best suited to devices on which there is no additional overhead associated with reading a data block or data object piece-wise.
[0044] The data object is located on the disk drive and the indicator bit pattern and compression information are retrieved from the disk drives (step 505 ).
[0045] The indicator bit pattern of the data object is examined (step 510 ). If the indicator bit pattern shows that the data object has not been compressed, then the entire data object is retrieved from the disk drives (step 515 ) and the data object returned to the requestor (step 520 ).
[0046] If the indicator bit pattern shows that the data object has been compressed, the compressed portion of the data object is then retrieved from the disk drives (step 525 ) the appropriate decompression algorithm is identified from the compression information associated with the data object and the selected decompression algorithm applied to the data object (step 530 ). Following decompression, the uncompressed data object is then returned to the requestor (step 535 ).
[0047] FIG. 6 shows an example of a data object stored or handled by the technique of FIG. 2 .
[0048] A data object 600 having bits a 1 to a 11 has the technique of FIG. 2 applied to it. If there is no compression algorithm that reduces the size of the data object by a threshold amount, then the uncompressed data object 605 is written to the disk drives. In this example, bit a 3 is the bit allocated by the application to be the indicator bit. Bit a 3 of data object 605 is cleared by setting the value to “0”.
[0049] If an appropriate compression algorithm can be identified, the data object written to the disk drives is data object 610 . In this example, the compressed data object is 5 bits in length, consisting of bits c 1 to c 5 . The compression information consisting of bits i 1 , i 2 and i 3 are incorporated into the compressed object and the indicator bit pattern at position 3 within the combined data object is “set” by setting the value to “1”.
[0050] FIG. 7 is a diagram of a data object handled by the technique of FIG. 3 described above.
[0051] A data object 700 is received by the application. In this example, bits a 2 and a 4 are reserved for use as an indicator bit pattern, and the application guarantees that a certain pattern, in this case “0 0”, will never occur.
[0052] If no appropriate data compression algorithm can be applied, the data object 705 is written to the disk drives.
[0053] Alternatively, if an appropriate compression algorithm can be found, this is applied to data object 700 resulting in a compressed data object of length 5 bits, c 1 to c 5 . Compression information bits i 1 , i 2 and i 3 are incorporated into the compressed object, as is the indicator bit pattern 715 A at position 2 and 715 B at position 4 showing that the data object has been compressed. The combined compressed data object 710 is then written to the disk drives.
[0054] In further alternative forms of the techniques of FIGS. 2 and 3 , the ASIC does not have available to it a plurality of compression data transformations or algorithms. The ASIC simply has one compression data transformation that could be preselected depending on the nature of the data to which the compression technique is to be applied. The single compression data transformation is applied to a received data object. If the compression data transformation reduces the size of the data set by a threshold amount, then the compressed data object is stored in accordance with the techniques of FIG. 2 or 3 above.
[0055] Maintaining a single data compression transformation has the potential to avoid the need to store with the data object compression information I and therefore further reduce the data transferred between the disk drives and the disk controller. One purpose of compression information I is to identify the compression data transformation used to generate the shortest compressed data object. Where the ASIC has available to it only a single compression data transformation, then the need to store separate compression information I can be reduced except in cases where the compression data transformation requires a symbol table or other data.
[0056] FIG. 8 shows an example of one type of computer system in which the above techniques of managing storage and retrieval of data objects are implemented. The computer system is a data warehousing system 800 , such as a TERADATA data warehousing system sold by NCR Corporation, in which vast amounts of data are stored on many disk-storage facilities that are managed by many processing units. In this example, the data warehouse 800 includes a relationship database management system (RDMS) built upon a massively parallel processing (MPP) platform. Other types of database systems, such as object-relational database management systems (ORDMS) or those built on symmetric multi-processing (SMP) platforms, are also suited for use here.
[0057] As shown here, the data warehouse 800 includes one or more processing modules 805 1 . . . y that manage the storage and retrieval of data in data storage facilities 810 1 . . . y . Each of the processing modules 805 1 . . . y manages a portion of the database that is stored in a corresponding one of the data storage facilities 810 1 . . . y . Each of the data storage facilities 810 1 . . . y includes one or more disk drives.
[0058] A parsing engine 820 organizes the storage of data and the distribution of data objects stored in the disk drives among the processing modules 805 1 . . . y . The parsing engine 820 also coordinates the retrieval of data from the data storage facilities 810 1 . . . y over communications bus 825 in response to queries received from a user at a mainframe 830 or a client computer 835 through a wired or wireless network 840 . An application-specific integrated circuit (ASIC) is associated with one or more disk controllers (not shown). The goal of the ASIC is to reduce the amount of data transferred between data storage 810 and the processing modules 805 .
[0059] The text above describes one or more specific embodiments of a broader invention. The invention also is carried out in a variety of alternative embodiments and thus is not limited to those described here. Those other embodiments are also within the scope of the following claims. | A technique for managing storage of a data object in a storage device involves receiving the data object (A) to store in the storage device, where the data object has an indicator bit pattern (P). Successive compression data transformations are applied to data object A to obtain respective corresponding compressed data objects, and one of these compressed data objects is selected, such that the selected compressed data object (C) has the shortest length with respect to the remaining compressed data objects. Compression information (I) is then associated with the compression data transformation used to generate data object C, and a threshold value T is calculated at least partly from the length of compression information I. If length (C)+T.gtoreq.length (A), then the indicator bit pattern of data object A is reset and the data object A is written to the storage device. If length (C)+T<length (A), then the indicator bit pattern of data object C is set, compression information I is incorporated into data object C, and data object C is written to the storage device. | 7 |
TECHNICAL FIELD
The present invention relates to a process for the combustion of a hydrocarbon fuel in a combustion zone and, more particularly, to a method for improving the solids inventory in the combustion zone of a circulating fluidized bed combustor.
BACKGROUND OF THE INVENTION
Operation of a combustion zone such as that found in a circulating fluidized bed combustor requires that the inventory of solids in the combustion zone be maintained at a specified level. The particle size distribution of the bed material in the combustion zone is also critical for proper operation. Because the feed, typically a solid hydrocarbon material as the fuel and an alkaline material as an adsorbent for sulfur capture, contains non-combustible ash components, there is a constant need to withdraw ash from the combustion zone. Finer ash particles are typically elutriated from the combustion zone and lost as fly ash. The elutriation rate for fly ash is generally difficult to adjust, and tends to remain invariant for a given combustor design. Consequently, the quantity of bed inventory typically is maintained by adjusting the rate at which additional ash is withdrawn from the combustion zone. This material is usually designated as bottom ash. The particle size distribution of the bed material will generally be a consequence of the uncontrolled fly ash elutriation rate, and the intrinsic agglomeration and attrition rates of the feedstocks. It can be influenced indirectly by the feed size distributions and the bottom ash withdraw rate.
The conventional operating practice of controlling the inventory of solids through control of the bottom ash withdraw rate, coupled with a lack of direct control on the particle size distribution of the bed inventory, results in several problems. Due to the intense mixing inherent in the design of a circulating fluidized bed combustor, the bottom ash withdrawn from the combustion zone is typically well mixed; i.e. its composition is similar to that of the average bed inventory. This material will necessarily include some fuel and adsorbent particles, as well as inert ash particles. While it is desirable to remove the inert ash particles from the combustion zone, it is inevitable that some fuel and adsorbent particles will also be rejected. Consequently, the bottom ash can contain a significant amount of unreacted feedstock, i.e. fuel and adsorbent materials. Recent investigations have shown further that the coarser bottom ash particles are relatively rich in unreacted fuel. Adsorbent losses can also increase when large limestone particles are used for sulfur capture. As is known in the art, the sulfation of larger limestone particles tends to cause plugging of the exterior particle pores, leaving an interior region which is unreacted. Hence the current methods of controlling the solids inventory results in a loss of unreacted fuel and adsorbent, which increases the operating cost for feeds, as well as costs for ash disposal. In addition, these techniques do not allow direct control of the particle size distribution of the bed inventory.
A further problem in the operation of a circulating fluidized bed combustor is the need to selectively remove large particles from the solids inventory in the combustion zone. It is generally known in the art that excessively large particles in the bed inventory can be detrimental to operation, even in small concentrations. These particles contribute disproportionately to erosion in the lower portions of the combustion zone. In addition, their inherently reduced heat transfer characteristics can allow them to act as nucleation sites for agglomeration. Once the agglomeration process begins, its rate tends to increase exponentially with particle size. In severe cases, agglomeration can cause the process to shut down completely. Consequently, there is a need to be able to remove undesirable large particles that are fed or which may form in the combustion zone, even if they are present in small quantities. Because the current methods for bottom ash withdraw are generally not size specific, these procedures can only remove the harmful size fractions by gross purging of the solids inventory. This practice will usually require an excessively high bottom ash withdraw rate, which will deplete the bed inventory and adversely affect the process operation. Hence, current methods do not permit excessively large particles to be practically purged from the combustion zone.
Thus there is a need to be able to independently control the quantity of the solids inventory and the particle size distribution of the solids inventory to permit recovery of unreacted feedstocks from the bottom ash and selectively remove detrimental size fractions from the combustion zone. The use of this invention will meet this need, thereby providing several operational benefits for the operation of a combustion zone such as that found in a circulating fluidized bed combustor. It will decrease the amount of feed materials which are lost in the bottom ash, thus saving both feedstock costs and ash disposal. It will also permit control of the particle size distribution of the solids inventory independent of the quantity of bed inventory. Consequently, excessively large particles can be purged from the bed inventory without adverse operation effects. This feature will reduce erosion in the combustion zone, and provide a method for controlling agglomeration. In addition, it can extend the operability range of the technology to use certain types of fuels and adsorbents which were previously too difficult to utilize in these combustors because their ash content is either too low, resulting in an insufficient quantity of bed material; or their ash is too friable, resulting in the too fine a particle size distribution. With such feedstocks, it is difficult to establish or maintain the solids inventory without direct, independent control of the particle size distribution of the bed material.
The need to control both the quantity and particle size distribution of the solids inventory in a circulating fluidized bed combustor has lead to several techniques which tend to cause these two parameters to be coupled, as discussed above. The individual problems, such as feedstock losses, erosion control, and prevention of agglomeration are also addressed by several methods. Feedstock losses in the fly ash have been addressed in the prior art, including the use of fly ash re-injection taught in U.S. Pat. No. 4,981,111 by Bennett et al. Losses in the bottom ash are typically minimized by design and operation considerations. For example, the particle size distribution for the fuel and adsorbent is usually specified to reduce the amount of unreacted material rejected from the combustion zone. Size specifications for fuel and adsorbent can help to reduce losses in the bottom ash. However, other considerations, such as pressure drop through the combustor, heat transfer requirements, and combustor stability usually are also considered in the specification of feed size distribution. As a result, the feed size can not often be optimized to minimize feed losses in the bottom ash. Indeed, some losses through the bottom ash are inevitable due to the inherent mixing of the solid phase in a circulating fluidized bed combustor.
In some installations, bottom ash is classified, i.e. separated by size fraction, prior to final discharge from the combustion zone in an attempt to strip the finer particle sizes from the bottom ash stream. Usually these classifiers strip the finer particles by contacting them countercurrently with an air stream. See for example U.S. Pat. No. 4,829,912 by Alliston et al. While this technique reduces the losses associated with the finer particles in the bottom ash, it does not recover the fuel or adsorbent lost in larger particles. Depending on the nature of the feed and operating conditions, the feed losses in the larger particles in the bottom ash can be comparable or greater than the losses in the finer particles in the bottom ash.
There have been several investigations into recovering unreacted adsorbent from bottom ash. These typically involve a chemical treatment of the ash, such as contacting with alkali or hydration. The chemical action is used to increase the availability of adsorbent inside the bed particles to the gas phase reactants.
Erosion problems are usually handled by placing sacrificial or wear-resistant materials in erosion-sensitive areas of the combustion zone. Typical examples include spray coatings or refractory applied to heat transfer tubes, or the use of high grade alloys to construct the heat transfer tubes for the lower regions of the combustion zone.
SUMMARY OF THE INVENTION
The present invention is a process for combusting a hydrocarbon fuel comprising:
(a) introducing a feed stream comprising oxygen gas, an adsorbent for sulfur capture and the hydrocarbon fuel into a combustion zone;
(b) combusting the fuel in the presence of the oxygen gas to form gaseous combustion products and solid combustion products consisting of fly ash and bottom ash wherein the fly ash is entrained within the gaseous combustion products and wherein the solid combustion products contained within the combustion zone at any one time constitutes the solids inventory;
(c) withdrawing at least a portion of the gaseous combustion products containing the entrained fly ash through the top of the combustion zone; and
(d) withdrawing at least a portion of the bottom ash through the bottom of the combustion zone;
(e) reducing the size of at least a portion of the bottom ash withdrawn in step (d);
(f) classifying the bottom ash from step (e) according to size;
(g) re-injecting a portion of the bottom ash classified in step (f) into the combustion zone; and
(h) discarding the remaining portion of the bottom ash classified in step (f).
In a preferred embodiment of the present invention, the bottom ash withdrawn in step (d) is size classified prior to particle size reduction in step (e) in order to remove size fractions which do not contain significant amounts of unreacted fuel or adsorbent.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram depicting one general embodiment of the process of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The process of the present invention is best illustrated with reference to a general embodiment thereof such as FIG. 1's embodiment. FIG. 1's process configuration consists of a combustion zone CZ1, a first particles size classifier PSC1, a particle size reducer PSR and a second particle size classifier PSC2. Referring now to FIG. 1, feed stream 10 comprising oxygen gas and a hydrocarbon fuel is introduced into combustion zone CZ1. The fuel is combusted in the presence of the oxygen gas to form gaseous combustion products and solid combustion products consisting of fly ash and bottom ash wherein the fly ash is entrained within the gaseous combustion products and wherein the solid combustion products contained within the combustion zone at any one time constitutes the solids inventory. At least a portion of the gaseous combustion products containing the entrained fly ash is withdrawn through the top of the combustion zone in line 12. Similarly, at least a portion of the bottom ash is withdrawn through the bottom of the combustion zone in line 14. As shown by the dotted lines in FIG. 1, a portion of line 14 can be optionally discarded in line 16 without regard to size or composition and/or optionally discarded in line 18 after being classified according to size in particle size classifier PSC1 in order to remove size fractions which do not contain significant amounts of unreacted fuel or adsorbent. The remaining withdrawn bottom ash in line 20 is subject to particle size reduction in particle size reducer PSR1 to produce an optimal particle size distribution. The effluent from PSR1 in line 22 is then classified according to size in particle size classifier PSC2. A portion of this classified ash is re-injected into the combustion zone in line 26 while the remaining portion is discarded in line 24.
The amount of bottom ash which can be reduced in particle size, classified and re-injected will depend on the design of the combustor facility. In principle, it is possible to process all bottom ash and recycle it to extinction. However, this mode requires that all ash be rejected from the system as fly ash. Consequently, the fly ash removal system must be designed to handle the entire load. This operating mode will maximize feedstock utilization for a facility. In addition, it could potentially reduce erosion in the combustion zone, since it reduces the population of larger particles in the combustion zone, which are known to be more erosive. In some cases, it may not be optimal to process all of the bottom ash. For some installations, the incremental savings in feedstock costs will not justify additional costs for increasing the capacity of the fly ash system to handle all the ash. In these cases, only a portion of the bottom ash should be processed. As shown in FIG. 1, there are three options for discarding a portion of the bottom ash before it is processed. In the first option, the total bottom ash stream is split without regard for particle size or composition as represented by line 16 in FIG. 1. The preferred second option is to classify the bottom ash according to size as represented by particle size classifier PSC1 in FIG. 1 in order to isolate those size fractions which have particular beneficial or detrimental characteristics. For example, it is known that larger bottom ash size fractions can be enriched in unreacted feedstocks. Only the beneficial fractions are then processed. Classifying the bottom ash stream prior to processing reduces the amount of inert material which is returned to the boiler. This step reduces heat losses associated with reheating the ash, decreases the burden on the fly ash removal system, and reduces the feed to the size reduction unit. A third option for discarding a portion of the bottom ash before it is processed would involve first discarding a portion of the bottom ash via the first option followed by discarding an additional portion of bottom ash via the second option.
An essential feature of the present invention is the ability to control the particle size distribution of the re-injected bottom ash. It is essential to recognize that the solid inventory in a circulating fluidized bed combustor is heterogeneous in terms of its size distribution and composition. The residence times for particles in the combustion system is very sensitive to the size of the particles. Since it is widely recognized that feedstock conversion will depend on the length of time that a particle stays in the combustor, it follows that feedstock utilization is also very sensitive to particle size. Consequently, it is essential that the particle size distribution of the bottom ash stream be altered prior to re-injection. In order to enhance the utilization of the larger particles, which are enriched in unreacted feedstocks, it is necessary to reduce their size so that their residence times will be increased when they are re-injected. However, it is essential that the bottom ash size not be reduced too much, since extremely small particles also have residence times too short for the complete utilization of the unreacted feedstocks. Due to the variation in residence time with size, there will generally be an optimal particle size distribution for the re-injected bottom ash which approximates the particle size distribution of the solid inventory in the combustion zone.
Many types of devices are known to achieve particle size reduction. Typical among these are hammermills, single- and double-roll crushers, and roller mills. The type of device which is most advantageous will depend on the nature of the bottom ash, and the desired size distribution of the product. Some devices, such as air-swept mills, are advantageous because they permit classification and size reduction of the ash to be completed in a single device, and are particularly useful for preventing excessive size reduction of the bottom ash.
The following examples are offered to demonstrate the efficacy of the present invention. These examples illustrate the benefits from recovering the unreacted fuel which is typically lost in the bottom ash, and the reduction in erosion which results from selectively removing coarser bed materials. All examples are based on data obtained from experimentation conducted at a commercial coal fired cogeneration facility in Stockton, Calif.
EXAMPLE 1
A 50 MWe circulating fluidized bed (CFB) boiler is fired with low sulfur (0.5 wt %) and low ash (6 wt %) bituminous coal. Limestone is fed to the combustor to capture sulfur oxides as calcium sulfate. Bottom ash and fly ash are withdrawn from the combustion zone with a portion of the fly ash re-injected into the combustion zone. The flowrates of feedstocks and ash, and amount of unburned carbon in the bottom ash are listed in Table 1. Lost fuel in the bottom ash in the three runs ranges from 52 to 143 lb/hr.
TABLE 1______________________________________Feedstock and ash flowrates for a 50 MWe CFB Facility(All flowrates in lb/hr) Fly Bottom Unreacted Fuel inRun Coal Limestone Ash Ash Bottom Ash______________________________________1 51900 2359 4610 1585 1432 51700 2039 5283 1017 1013 51400 1501 4794 626 52______________________________________
The heterogeneous nature of the bottom ash from these runs is shown in Table 2, which summarizes the distribution of mass and unreacted fuel as a function of particle size. It shows that essentially all of the mass of bottom ash is comprised of particles greater than 90 μm in size, and most is larger than 425 μm. Furthermore, most of the unreacted fuel is present in particles ranging from 425 μm to 9500 μm. Although the finest particles have fairly high concentrations of unreacted fuel, their mass is fairly small.
TABLE 2__________________________________________________________________________Bottom ash mass and unreacted fuel (UF) distribution as a functionof particle size for a 50 MWe CFB Facility (All data in wt %)Run 0-45 μm 45-63 μm 63-88 μm 88-420 μm 420-3350 μm 3350-9500 μm >9500 μm__________________________________________________________________________1 Mass 1.1 1.1 0 41.6 16.2 25.5 14.51 UF 40.6 10.3 0 2.6 17.7 16.4 3.32 Mass 1.5 1.1 0 33.4 17.3 31.7 152 UF ND ND 0 2.4 16.1 18 3.83 Mass 1.4 1.2 0 33.0 18.1 28.0 18.33 UF ND ND 0 3.5 13.2 17.91 3.2__________________________________________________________________________ ND: not determined
EXAMPLE 2
A representative sample of bottom ash from the combustor of Example 1 was processed without prescreening in a Williams Patent Crusher hammermill Model GP-1512 (TRADEMARK). The hammermill reduced the average particle size of the bottom ash from approximately 600 microns to between 100 and 200 microns. The amount of fines (passing U.S. Standard Sieve #200) increased from approximately 0 wt % in the bottom ash to between 16 wt % and 32 wt %. Top size of the material decreased from greater than three-quarter-inch to less than one-eighth-inch. As seen in the following Example 3, the size reduction achieved in these runs is sufficient to permit recovery of up to 85% of the unreacted fuel upon re-injection of the processed bottom ash.
EXAMPLE 3
A simulation of bottom ash re-injection was made for the combustor of Example 1, using the ash analysis from Run 1 of Example 1 and the results of the hammermill tests in Example 2. The calculations show the amount of fuel that could be recovered from the bottom ash. Calculations were made assuming that 50%, 75%, and 100% of the bottom ash is fed to the hammermill with no size classification prior to size reduction. Results are summarized in Table 3. The results show that up to 85% of the unreacted fuel can be recovered from the bottom ash. However, increasing recovery results in a greater fly ash flow rate.
TABLE 3______________________________________Improvements to facility per Run 1, as a function of bottom ashre-injection rate (All flowrates in lb/hr)Hamermill Net Fly Fuel Saved FromFeed Ash Net Bottom Ash Bottom Ash______________________________________ 0 (0% of 4610 1585 0bottom ash) 792 (50% of 5403 792 61 (43%)bottom ash)1189 (75% of 5006 396 92 (64%)bottom ash)1585 (100% of 6195 0 122 (85%)bottom ash)______________________________________
EXAMPLE 4
A second series of calculations following the method of Example 3 was made for a system in which bottom ash is classified prior to being fed to the hammermill. For these cases, classification is assumed to be done with mechanical screens, although other processes are available. Classification allows the operator to remove particles with fuel contents that are not economical to recover. Results are presented for single screening, which rejects those bottom ash fraction passing through the sieve; and for double screening, which rejects bottom ash fractions either too fine or too coarse. The calculations were made using various U.S. Standard Sieve sizes, which are familiar in the art. The results show that size classification prior to size reduction can allow a substantial fraction of the unreacted fuel to be recovered without the large increase in fly ash flow rate, and with less total feed to the hammermill, as found in Example 3. Results are summarized in Table 4.
TABLE 4______________________________________Improvements to facility per Run 1, with screening of bottom ashprior to size reduction (All flowrates in lb/hr) Processed Net Net Fuel SavedSieve Ash Size Hammermill Fly Bottom fromSize(s) (μm) Feed Ash Ash Bottom Ash______________________________________#170 >88 1500 6160 35 114 (80%)#400 >420 890 5501 694 114 (80%)#40 × 420 < X < 661 5270 924 108 (76%)3/8-inch 9500______________________________________
Results from the above Examples 3 and 4 show that the process of this invention allows unreacted fuel to be recovered from the bottom ash, which reduces operating costs. A second benefit of this invention is that it provides a means to purge larger particles from the combustor without depleting the bed inventory. This benefit is achieved by increasing the bed ash removal rate, and processing the bed ash to remove undesirable particles. The processing may involve simple size classification, or it may involve a combination of size selection and size reduction, depending on the nature of the combustor and the fuel. Removing the larger particles from the bed can reduce the erosion rates in the combustor, and decrease the potential for agglomeration. The following example illustrates potential reduction of erosion in the combustor.
EXAMPLE 5
Investigations have shown that erosivity, as measured by thickness loss, increases approximately linearly with particle size for the conditions of the study. These findings indicate that the relative erosivity of the bed material in a combustor will decrease as the amount of material withdrawn from the bed, processed for size reduction, and re-introduced into the bed increases. Using the data of Example 1, Run I as a base case, and the results of Example 2, the relative erosivity of the bed is estimated to decrease approximately 10% after processing.
The present invention has been described with reference to a general embodiment thereof. This embodiment should not be seen as a limitation of the scope of the present invention; the scope of such being ascertained by the following claims. | A process is set forth for directly controlling the quantity and particle size distribution of the solid inventory inside a circulating fluidized bed combustor. A portion of the bed ash is withdrawn from the combustor as bottom ash. The particle size distribution of the stream is adjusted, such as by a hammermill, to a specified distribution. Finally, a portion of the adjusted ash is re-injected into the combustor. The process may be facilitated by size classifying the bottom ash prior to size reduction. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/793,297 filed Apr. 18, 2006; the disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The invention generally relates to media storage containers and, more particularly, to promotional packaging for a media storage container. Specifically, the invention relates to promotional packaging for a media storage container that allows the user to physically interact with the packaging.
[0004] 2. Background Information
[0005] Various media storage containers are known in the art. Some of the most common storage containers for recorded media are book-like containers having a lid connected to a base with a hinge. These containers typically allow a printed promotional slip sheet to be connected to the lid, hinge, and base where one surface of the sheet is viewable by the user. Those who manufacture and sell recorded media desire innovative packaging that attracts the consumer's attention while also providing space for printed information and the opportunity for consumer interaction with the packaging.
BRIEF SUMMARY OF THE INVENTION
[0006] The invention provides a media storage and display sleeve that is adapted to fit over a media storage container to provide a unique interactive marketing piece to be viewed and handled by the consumer. The sleeve includes an inner sleeve that receives the traditional media storage container and a pair of outer sleeves that slide back and forth over the inner sleeve between closed and open configurations. Stops are used to prevent the outer sleeves from being readily removed from the inner sleeve.
[0007] In one configuration, the media storage and display sleeve includes an inner sleeve that receives a media storage container and a pair of outer sleeves that slide back and forth over the inner sleeve. Stops prevent the outer sleeves from sliding directly off the inner sleeve. The stops include cantilevered tabs that engage to limit the relative movement of the sleeves. In an alternative embodiment of this configuration, one of the tabs is double thickness. The double thickness of the tab prevents pinching.
[0008] The invention provides another configuration wherein a media storage container functions as the inner sleeve and the outer sleeves slide back and forth directly over the storage container. Stops are used to limit the movement of the outer sleeves.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0009] FIG. 1 is a perspective view of one configuration for a media storage and display sleeve with the two outer sleeves in the closed configuration.
[0010] FIG. 2 is a perspective view of the FIG. 1 configuration with the two outer sleeves in the open configuration.
[0011] FIG. 3 is a section view taken along line 3 - 3 of FIG. 2 .
[0012] FIG. 4 is an enlarged section view of the interlocking tabs encircled in FIG. 3 .
[0013] FIG. 5 includes FIGS. 5-5E which depicts a series of complementary end wall configurations.
[0014] FIG. 6 is a view similar to FIG. 3 of an alternative embodiment of the invention.
[0015] FIG. 7 is an enlarged section view of a stop of the FIG. 6 alternative embodiment.
[0016] Similar numbers refer to similar parts throughout the specification.
DETAILED DESCRIPTION OF THE INVENTION
[0017] A first configuration of the media storage and display sleeve is indicated generally by the numeral 2 in the accompanying drawings. The first configuration of sleeve 2 is configured to receive a traditional media storage container 4 such as a DVD container, a CD container, a VHS box, a video game cartridge container, a UMD container, or the like. Container 4 holds an item of recorded media 5 in the manner for which it was designed. For example, a DVD container 4 may include a hub 7 adapted to snap through the central opening in the DVD to hold the DVD in place. Sleeve 2 does not interfere or enhance the manner in which container 4 operates. Sleeve 2 is used to provide a plurality of interactive graphic display areas 6 . Areas 6 may be used to display information related to the item of recorded media stored within container 4 . Areas 6 also may be used to display information or graphics related to the manufacturer of sleeve 2 , the distributor of container 4 , the retailer who is selling container 4 , or other promotional material such as a sweepstakes game or an instant-win game.
[0018] Sleeve 2 generally includes an inner sleeve 8 adapted to closely surround container 4 and a pair of outer sleeves 10 that closely surround and slide against inner sleeve 8 . Sleeves 8 and 10 may be fabricated from paper-based (such as paperboard) materials. Sleeves 8 and 10 also may be fabricated from other materials such as plastics, metals, glass, or recyclable materials. Sleeves 8 and 10 may be formed (cut from sheets of material) flat and folded into the erected configurations shown in the drawings. When cut from blanks, the locations where sleeves 8 and 10 are folded may be scored or indented to make it easier to fold the flat blanks into sleeves 8 and 10 .
[0019] Inner sleeve 8 defines a chamber that is configured to receive at least a substantial portion of container 4 . Container 4 may be secured inside sleeve 8 with a connector which may be a mechanical or adhesive connector. In another configuration, inner sleeve 8 is configured to frictionally receive container 4 tightly enough to prevent container 4 from easily slipping from inner sleeve 8 . In the configuration shown in the drawings, inner sleeve 8 is configured to be disposed tightly enough around container 4 to allow container 4 to be forced out of sleeve 8 with the user's fingers or a tool. In another configuration, container 4 may be held within sleeve 8 by appropriate holders. Such holders may include tape, clips, friction members, shrink wrap and other such devices. In another configuration, container 4 may be integrated with sleeve 8 such that sleeve 8 functions as part of container 4 .
[0020] Outer sleeves 10 slide over inner sleeve 8 between closed ( FIG. 1 ) and open ( FIG. 2 ) configurations. In the closed configuration, outer sleeves 10 may completely hide the top, bottom, and side walls of inner sleeve 8 . Outer sleeves 10 may frictionally engage inner sleeve 8 so that the relative position of outer sleeves 10 is frictionally maintained. Holders or ratchets also may be used to maintain the positions of outer sleeves 10 . Each outer sleeve 10 has an inner end wall 12 that may abut each other when the outer sleeves 10 are in the closed configuration. End walls 12 may complement each other when outer sleeves 10 are in the closed configuration as shown if FIG. 5 . In the exemplary configuration of FIGS. 1-4 , end walls 12 are both perpendicular to the longitudinal direction of inner sleeve 8 and abut each other when outer sleeves 10 are closed. Other end wall configurations may be curved ( FIG. 5 ), wavy ( FIG. 5A , crenulated or interlocking ( FIGS. 5B, 5D , and 5 E), and wavy ( FIG. 5C ).
[0021] Display sleeve 2 includes a pair of stops 20 that impede outer sleeves 10 from sliding off the outer ends of inner sleeve 8 . In the context of this application, stops 20 are considered to impede outer sleeves 10 from sliding off the ends of inner sleeve 8 even though stops 20 or sleeves 8 / 10 may be manipulated to allow complete separation of sleeves 8 and 10 . Stops 20 may be in the form of cooperating tabs 22 and 24 that are integrally formed from sleeves 8 and 10 . One or both or tabs 22 and 24 may be doubled over to prevent pinching. In the exemplary embodiment, tab 24 has two layers to increase the strength of tab 24 and to prevent tab 24 from becoming pinched inside tab 22 . This configuration provides allows sleeve 10 to operate smoothly. Stops 20 also may be provided in alternative configurations such as stop walls, clips, or interlocking projections and depressions. Stops 20 are depicted on locations the top of sleeve 2 but may be disposed on the bottom, sides, or a combination of these locations.
[0022] In the exemplary embodiment of the invention, tabs 22 and 24 are formed by folding sections of material integral to sleeves 8 and 10 . These sections are defined when sleeves 8 and 10 are cut into blanks from raw material sheets. Tab 22 is defined by creating a fold 23 to place tab 22 inwardly of the end of sleeve 10 . In the embodiment of FIGS. 1-4 , fold 23 defines inner end wall 12 . When other end wall 12 configurations are used, tab 22 may be folded or connected with a connector such as an adhesive or a mechanical connector. Tab 24 is defined by creating at least one fold 25 to place tab 24 back over the top of sleeve 8 as shown in FIG. 4 . A second fold 26 may be formed to double the thickness of tab 24 .
[0023] Sleeve 2 provides graphic areas on the four outer surfaces of the inner sleeve 8 in addition to the four outer surfaces of both outer sleeves 10 . This configuration essentially doubles the available surface for printing information as compared sleeve 8 alone. This configuration allows the inner and outer graphic areas to be related and creatively used to engage or entertain the user. In one example, the inner graphic can be an extension of the two outer graphics such that the inner and outer graphic areas combine to form a single graphic when the outer sleeves 10 are in the open configuration. The inner graphic may also be a graphic image that is logically subsequent to the outer image such that the user first comprehends the outer image and then opens the sleeves to see what the subsequent image reveals (such as a riddle and an answer—or different steps of a storyboard). Another configuration provides graphic images on the outer sleeves with text information about a company or a product on the inner sleeve (or vice versa).
[0024] FIGS. 6 and 7 depict an alternative embodiment 28 of the invention wherein container 4 functions as inner sleeve 8 . Sleeve 28 includes container 4 and both outer sleeves 10 which slide back and forth between the open and closed configurations. In this embodiment, container 4 includes a projection 30 that functions as part of stop 20 to impede the removal of outer sleeve 10 from container 4 .
[0025] In the foregoing description, certain terms have been used for brevity, clearness, and understanding. No unnecessary limitations are to be implied therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed.
[0026] Moreover, the description and illustration of the invention is an example and the invention is not limited to the exact details shown or described. | A media storage and display sleeve is adapted to fit over a media storage container to provide a unique interactive marketing piece to be viewed and handled by the consumer. The sleeve includes an inner sleeve that receives the traditional media storage container and a pair of outer sleeves that slide back and forth over the inner sleeve between closed and open configurations. Stops are used to impede the outer sleeves from being readily removed from the inner sleeve. | 6 |
PRIORITY CLAIM
[0001] This application claims the benefit of U.S. Provisional Application No. 60/472,970 entitled “SEMICONDUCTOR ELECTRONIC DEVICES AND METHODS,” filed May 23, 2003.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] Embodiments disclosed herein generally relate to semiconductor devices. More particularly, embodiments relate to transistors having certain desired properties and methods of manufacturing such transistors.
[0004] 2. Description of the Relevant Art
[0005] During the past few years, there has been interest in the use of wide-bandgap semiconductors, e.g., SiC and GaN, for applications in high-power and high-temperature electronic devices (e.g., p-i-n rectifiers, heterojunction bipolar transistors (HBTs), heterojunction field-effect transistors (HFETs), and Schottky barriers). For some applications, GaN devices are predicted to out-perform Si and SiC devices for power applications. Consequently, Group III-nitride materials are receiving attention for high-power electronic applications owing to their promising material properties. While there have recently been demonstrations of Group III-V nitride-based HFETs, to date, power devices performing at or near the theoretical limits for GaN do not appear to have been reported.
[0006] It is believed that microwave power devices based on GaAs have almost reached their power limits, whereas the needs for higher microwave power densities are increasing. One of the possibilities for improving power performance at X-band and higher frequencies is to use new material systems. Group III-nitride materials may be attractive for high-power and high-temperature devices because of their intrinsic properties: large energy bandgap, high breakdown voltage, and high peak electron velocity. Microwave power devices such as AlGaN/GaN HEMTs have demonstrated impressive output power density, greater than those of GaAs. For microwave power high electron mobility transistors (HEMTs), a high current gain cut off frequency along with a high saturation current may be desirable. A high drain current of 1,500 mA/mm with a transconductance of 300 mS/mm has been reported with a classic modulation-doped HEMT structure.
SUMMARY OF THE INVENTION
[0007] AlGaN/GaN HFETs may be candidates for future applications in high power, high-frequency, high power, and high-temperature electronics (e.g., BMD-class X-band radar systems) because of the fundamental characteristics of Group III-nitride materials. For example, in certain embodiments, a transistor having desired performance characteristics may include one or more AlN layers and/or one or more SMASH superlattice barriers combined with one or more n-type delta-doped regions. Alternately, in certain embodiments, one or more AlN and one or more SMASH superlattice barriers may be combined without the n-type delta-doped regions.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the accompanying drawings in which:
[0009] FIG. 1 a : depicts a schematic diagram of an energy-band diagram for a SMASH in the InAlP/InGaP materials system, according to an embodiment;
[0010] FIG. 1 b : depicts a schematic diagram of an energy-band diagram for multiple-quantum barrier in the InAlP/InGaP materials system, according to an embodiment;
[0011] FIG. 2 a : depicts a schematic diagram of a SMASH barrier HFET structure showing superlattice charge layers with an AlN barrier, according to an embodiment;
[0012] FIG. 2 b : depicts a schematic expanded view of the conduction band structure of an AlN/AlxGal-xN SMASH barrier for enhanced carrier confinement in the channel, according to an embodiment;
[0013] FIG. 3 : depicts a diagram of drain current to drain voltage for a D 2 B 2 AlGaN/AlN/GaN HFET, according to one embodiment;
[0014] FIG. 4 : depicts a diagram transconductance to gate voltage for a D 2 B 2 AlGaN/AlN/GaN HFET, according to one embodiment;
[0015] FIG. 5 : depicts a diagram of drain current to drain voltage for a D 2 B 2 AlGaN/AlN/GaN HFET, according to one embodiment;
[0016] FIG. 6 : depicts a diagram of current gain to frequency for a D 2 B 2 AlGaN/AlN/GaN HFET, according to one embodiment;
[0017] FIG. 7 : depicts a diagram of minimum noise and associated gain to frequency for a D 2 B 2 AlGaN/AlN/GaN HFET, according to one embodiment;
[0018] FIG. 8 : depicts a diagram of drain current to drain voltage for a D 2 B 2 AlGaN/AlN/GaN HFET, according to one embodiment;
[0019] FIG. 9 : depicts a diagram of drain current and g m to gate voltage for a D 2 B 2 AlGaN/AlN/GaN HFET, according to one embodiment;
[0020] FIG. 10 : depicts a diagram frequency response for a D 2 B 2 AlGaN/AlN/GaN HFET, according to one embodiment;
[0021] FIG. 11 : depicts a diagram of drain current to drain voltage for a D 2 B 2 AlGaN/AlN/GaN HFET, according to one embodiment;
[0022] FIG. 12 : depicts a diagram of drain current and g m to gate voltage for a D 2 B 2 AlGaN/AlN/GaN HFET, according to one embodiment;
[0023] FIG. 13 : depicts a HFET with AlN barrier and delta-doped charge layer, according to an embodiment;
[0024] FIG. 14 : depicts a HFET with AlN/GaN superlattice charge and buffer layer, according to an embodiment; and
[0025] FIG. 15 : depicts a HFET with SMASH barrier layer, according to an embodiment.
[0026] While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the drawing and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] In an embodiment, AlGaN/GaN heterojunction field-effect transistors (HFETs) may be used in high-power, high-frequency, and high-temperature electronics, because of the fundamental characteristics of Group III-nitride materials. Improved high-power HFET performance has been recently achieved and a power density of 10.7 W/mm at 10 GHz has been demonstrated. For high-power device applications, a high drain-source current, I DS , along with a high transconductance and a large source-drain breakdown voltage may be desirable.
[0028] In an embodiment, a large source-drain current, I DS , may be achieved if the sheet charge density, n s , the carrier mobility, μ n , and the saturation drift velocity, v s , in the channel have relatively large values. Currently, a large source-drain current may be achieved by using undoped or modulation-doped AlGaN/GaN structures. Another method of achieving a large source-drain current may include increasing the aluminum mole fraction (and therefore, the bandgap) in an AlGaN barrier. Although, increasing the Al mole fraction in the AlGaN cap layer may lead to higher n s , it may also lead to a decrease in μ n . As a result, n s μ n product improvement may be limited.
[0029] Large source-drain current devices may be referred to as “high-electron mobility transistors” or HEMTs. Recently, the use of a binary barrier of AlN was reported to increase the low-field electron mobility, μ n , and n s in the channel, yielding an n s μ n product of 2.28×10 16 V-s. However, the FET device performance (e.g., I DSmax and g m ) did not appear to be improved compared to the performance achieved by a “standard” modulation-doped HFET.
[0030] Embodiments disclosed herein include delta-doped heterostructure FET designs. Such designs may include the use of one or more AlN barriers. Additionally, one or more superlattice barriers may be included in delta-doped heterostructure FET designs disclosed herein. One or more AlN and/or one or more superlattice barriers may be combined with one or more n-type delta-doped regions. Alternately, in certain embodiments, one or more AlN and one or more superlattice barriers may be combined without the n-type delta-doped regions. In embodiments that include n-type delta-doped regions, the n-type delta-doped regions may improve the current carrying capabilities of the HFET. In certain embodiments, n-type delta-doped regions have the additional benefits of reduced gate leakage, low noise, high g m , and capability of sustaining a large voltage across the drain source region (large V DS ) prior to breakdown of the device. The structures described above may demonstrate relatively high n s μ n product, relatively large drain currents, relatively high values of extrinsic transconductance, relatively low noise figures at 17 GHz, and/or transconductance values close to the state-of-the-art.
[0031] An superlattice heterostructure includes a series of alternating layers of smaller-bandgap “quantum well layer” and larger-bandgap “barrier layers.” Quantum mechanics predicts that an electron has a non-zero reflection probability from a barrier lower than the energy of the electron. With appropriate design of the barriers and wells, the reflected wave may be made to interfere destructively with the incident electron wave. A propagation matrix is calculated for each interface that calculates the ratio of incident wave, reflected wave and transmitted wave. For a multi-period heterostructure, these propagation matrices are multiplied together yielding the effective propagation matrix for the superlattice. Such an superlattice structure effectively increases the heterojunction barrier while reducing the lattice mismatch and alloy scattering.
[0032] In one embodiment, the super lattice structure may be improved by growing a specially designed superlattice heterobarrier that has a non-periodic structure. An example of one such barrier with a special increased electron reflectivity design we have developed is called a “strain-modulated aperiodic superlattice heterobarrier” (SMASH™) and will be described in further detail below.
[0033] Embodiments disclosed herein include methods to improve performance of Group III-N HFET devices in terms of power, frequency response, noise and stability. Specifically, a number of HFET device structures are disclosed. For example, a first HFET device structure including delta-doped AlGaN/AlN/GaN HFETs using an ultra-thin AlN binary superlattice barrier layer is depicted in FIG. 2A . Other examples of HFET device structures include delta-doped and undoped strain-modulated aperiodic superlattice heterobarrier (SMASH) electron donor and confinement structures.
[0034] In an embodiment, a specially designed SMASH barrier may be used in an HFET device to improve carrier confinement and to reduce the leakage current for high-power devices. Such SMASH barriers may include quantum-mechanically designed barriers, which reflect electrons back into the channel. Such SMASH barriers may further provide a high carrier density from the combined effects of the piezoelectric and polarization charges and the carriers provided by delta doping. As used herein a SMASH barrier generally refers to a barrier in which successive well layers generally have an increasing band gap in the conduction band energy diagram.
[0035] In a strain-modulated aperiodic superlattice heterobarrier, successive well layers have an increasing band gap in the conduction band energy diagram for the SMASH as shown in FIG. 1A for the InAlP/InGaP/GAAs system. A schematic drawing of the conduction band energy of a conventional multiple quantum barrier structure is shown in FIG. 1B . For the InAlP/InGaP/GaAs system, this corresponds to an increasing amount of strain in the consecutive wells of the superlattice. If a single quantum well is sandwich between a pair of SMASHs, the tendency of the electrons to thermalize into the well will be enhanced significantly because of the decreasing potential of the superlattice well layers towards the single quantum well. Once confined in the quantum well, the thermionic emission of the electrons will be greatly reduced due to the increased electron reflectivity of the SMASH. Therefore, the SMASH enhances the collection and confinement of the carriers. These arguments are confirmed both by theoretical calculations and by experimental observations.
[0036] A schematic diagram of an HFET device including a SMASH barrier is depicted in FIG. 2A , and generally referenced by numeral 100 . HFET device 100 includes superlattice charge layers and at least one AlN barrier. As used herein a superlattice structure refers to a stack of repeating alternate layers.
[0037] The HFET device is formed on a substrate. Suitable substrates for the formation of an HFET include, but are not limited to c-plane (0001) Al 2 O 3 (sapphire), 4H—SiC, 6H—SiC, thick AlN/sapphire, bulk GaN, AlN substrates, etc. While (0001) sapphire may be used for GaN growth because of its availability and relatively low cost, the lattice and thermal expansion coefficients are quite different from those of the Group III-N materials. It is believed that SiC has better thermal and lattice match to the Group III-N compounds, particularly to AlN, yet the crystalline quality of 6H— and 4H—SiC substrates is still not as high as sapphire. Furthermore, the surface roughness and subsurface damage for “typical” commercial SiC substrates are believed to be inferior to that of sapphire. While the cost of 2.0 in. diameter semi-insulating 4H—SiC substrates on the “open market” may be about forty times that of a 2.0 in. diameter sapphire substrate, the performance advantages of electronic devices fabricated from heteroepitaxial GaN/SiC films are documented.
[0038] In forming a device as disclosed herein, the quality of Group III-N epitaxial layers may be directly related to the quality and lattice constant of the substrate on which the Group III-N material is grown. For the growth of Group III-N epitaxial layers on sapphire or SiC substrates for high-power devices, low-pressure metalorganic chemical vapor deposition (MOCVD) or molecular-beam epitaxy (MBE) may be employed. For example, in an embodiment, GaN epitaxial layers may be grown in an EMCORE D125 reactor at pressures of ˜200 Torr. In another embodiment, a Thomas Swan Close Coupled Showerhead (CCS) MOCVD reactor system with a seven wafer capacity may be used. Other reactor systems may also be suitably used to grow such structures. AlGaN layers may be grown in the same MOCVD reactor at ˜50 Torr in order to avoid adduct formation as much as possible. Device structures may be grown in a H 2 ambient using adduct-purified trimethylgallium (TMGa) and trimethylaluminum (TMAl) as metal alkyl sources, and NH 3 as the nitrogen source. Silane (SiH 4 ) and bis(cyclopentadienyl)-magnesium (Cp 2 Mg) may be employed as n-type and p-type dopants, respectively. Other metalorganic, hydride and dopant sources may also be used, as are known in the art. A two-temperature growth process may be employed with a low-temperature thin AlN buffer layer (BL) for SiC substrates, and with high-temperature (HT) layers grown for the device active region. The MOCVD growth of GaN on SiC may begin with a ˜100 nm high temperature (Tg˜1050° C.) AlN buffer layer, although various “graded AlGaN” conducting buffer layers have been developed for the growth of optoelectronic devices on SiC. In embodiments disclosed herein, it may be desirable to grow these layers without creating cracks in the epitaxial structure (e.g., by the use of various types of stress-relieving buffer layer structures).
[0039] In FIG. 2A , an undoped GaN layer is formed on a substrate of SiC. Undoped GaN layer may be formed from trimethyl gallium and ammonia in a MOCVD reactor at about 1050° C.
[0040] A superlattice structure may be formed on top of the undoped GaN layer. In one embodiment, a SMASH superlattice structure is formed that includes alternating layers of undoped AlN and n-type doped AlGaN layers, as depicted in FIG. 2A . In FIG. 2A , superlattice includes 8 layers of alternating AlN and AlGaN layers. AlN layers are undoped and are formed by an epitaxial growth process. The AlGaN layer is then formed on top of the AlN process, with doping of the AlGaN layer occurring by introducing SiH 4 during into the reactor during the growth process. The layers are designed to create a superlattice heterobarrier that has a non-periodic structure. FIG. 2B depicts a schematic representation of the conduction band structure of HFET device 100 .
[0041] Delta-doped binary-barrier (D 2 B 2 ) HFET structures, and SMASH-FETs, may have several significant features. In an embodiment, a basic D 2 B 2 HFET structure incorporates a binary AlN barrier and a delta-doped charge layer in the AlGaN near this AlN barrier. Such a structure may allow electrons to tunnel through this barrier and to enhance the free charge in the channel. Such structures may also reduce alloy scattering at the AlN—GaN interface as compared to an AlGaN—GaN interface.
[0042] AlGaN/GaN HFETs having a gate length of 0.2-0.5 μm have been fabricated. Using the D 2 B 2 structure, improved n s ×mobility product has been measured for electrons in the channel of an AlGaN/GaN HEMT. For example, in one experiment using a D 2 B 2 AlGaN/GaN HFET structure, including a binary AlN barrier and an AlGaN delta-doped charge layer, a two-dimensional electron gas having a carrier mobility of μ n =1,058 cm2/V−s and a sheet carrier density of n s =2.35×10 13 cm −2 at room temperature were obtained, resulting in a n s μ n product of 2.49×10 16 /V−s. In experiments, AlGaN/AlN/GaN HFET devices with 0.15 μm gate lengths exhibited maximum current densities as high as I DSmax =1.8 A/mm at V G =+1 V. FIG. 3 depicts a plot of I DS vs. V DS for an L G =0.15 μm D 2 B 2 AlGaN/AlN/GaN HFET. FIG. 4 depicts a plot of Transconductance vs. Gate Voltage for an L G =0.15 μm D 2 B 2 AlGaN/AlN/GaN HFET. FIG. 4 shows that such devices may exhibited peak transconductance of up to g m =350 mS/mm. FIG. 5 shows a plot of I DS vs. V DS for an L G =0.25 μm D 2 B 2 AlGaN/AlN/GaN HFET. FIG. 5 shows that AlGaN/AlN/GaN HFET devices with 0.25 μm gate lengths exhibited g m =240 mS/mm. FIG. 6 depicts frequency response data for an L G =0.25 μm D 2 B 2 AlGaN/AlN/GaN HFET showing a current gain (h 21 ) and unilateral figure of merit (U) and indicating f T =50 GHz and f max =130 GHz.
[0043] L G =0.25 μm devices have demonstrated a record low-noise power for this gate length, as demonstrated in FIG. 7 . FIG. 7 depicts the minimum noise figure and associated gain vs. frequency for V DS =10 V and 15V. The noise characteristics of these devices have been measured to be about 1.6 dB at 10 GHz, an exceptionally low value. Noise characterization was performed for the frequency range of 2-18 GHz to determine Γ opt , the noise resistance (R n ), the minimum noise figure (F min ), and the associated gain (G a ). For L G =0.25 μm D 2 B 2 HFETs, a state-of-the-art minimum noise figure of F min =0.93 dB with 7 dB of associated gain was obtained at 17 GHz and at 10 GHz, the noise figure of the D 2 B 2 HFET was 1.1 dB with 10 dB associated gain. These results indicate that the D 2 B 2 structure may be compatible with high current densities, as well as with high-frequency and low-noise performance desired for X-band BMD-class receivers.
[0044] D 2 B 2 devices having gate lengths of between about L G =0.15 μm and about 0.5 μm have been formed. The devices may approximate short-gate lengths (e.g., for high-frequency applications) and longer-gate lengths (e.g., for high power devices). The formed devices have been used to evaluate the performance of the materials used to form the devices. In experiments, AlGaN/AlN/GaN HFET. FIG. 8 depicts a plot of I DS vs. V DS for an L G =0.5 μm D 2 B 2 AlGaN/AlN/GaN HFET. As shown in FIG. 8 , devices with 0.5 μm gate lengths exhibited maximum current densities as high as I DSmax =1.5 A/mm at V DS =9 V. FIG. 9 depicts a plot of I DS and g m vs. V G for an L G =0.5 μm D 2 B 2 AlGaN/AlN/GaN HFET. As shown in FIG. 9 , the I DS -V G curves are nearly linear, corresponding to a large, relatively flat g m vs. V G curve. The peak I Dsmax =1.4 A/mm and g m exceeds 230 mS/mm. It is believed that these values are record numbers for the performance of AlGaN/GaN HFETs with L G approximately 0.5 μm (e.g., in the range of about 0.3 to 0.7 μm). FIG. 10 shows the frequency response data for an L G =0.5 μm D 2 B 2 AlGaN/AlN/GaN HFET indicating f T =20 GHz and f max =about 75 GHz.
[0045] FIG. 12 depicts a plot of I DS vs. V DS for an L G =0.15 μm D 2 B 2 AlGaN/AlN/GaN HFET after metalization. As shown in FIG. 12 , devices with 0.15 μm gate lengths exhibited maximum current densities as high as I DSmax >1.8 A/mm at V DS =9 V. FIGS. 12 and 13 , the L G =0.15 μm devices exhibit even higher values of I DSmax greater than 1.8 A/mm and g m values as high as 330 mS/mm. It is believed that these values are record numbers for the performance of AlGaN/GaN HFETs with L G approximately 0.15 μm. FIG. 13 depicts a plot of I DS and g m vs. V G for an L G =0.15 μm D 2 B 2 AlGaN/AlN/GaN HFET after metalization. As shown in FIG. 13 , the I DS -V G curves at V DS are nearly linear, corresponding to a large, relatively flat g m vs. V G curve. The peak I Dsmax >1.8 A/mm and g m exceeds 330 mS/mm.
[0046] Some known designs for high-power Group III-N gallium-nitride-based FETs employ a single AlGaN barrier layer to confine the electrons to the channel. This channel carries the current when the device is “ON.” At high currents, high-energy charge carriers may be injected into this barrier reducing the current in the channel, lowering the effective mobility, and/or reducing the effect of the gate voltage on the current flow. In certain embodiments disclosed herein, the effective energy barrier may be increased by a significant amount due to quantum-mechanical reflection of carriers. Such reflections may enhance the performance of the device by maintaining the charge in the channel even for the high-current situations. Reflection may also improve the high-frequency performance. Certain embodiments may include both a superlattice and delta doping, which may provide more free charge carriers (electrons) to the channel than a conventional doped or undoped AlGaN charge layer.
[0047] An additional embodiment of an HFET design is represented schematically in FIG. 13 . FIG. 13 depicts an embodiment of an HFET that includes an AlN barrier and delta-doped charge layer. While FIG. 13 depicts a SiC substrate, it should be understood that the HFET depicted in FIG. 13 may be formed on any other type of substrate as described previously. The process of forming an HFET as depicted in FIG. 13 includes forming a buffer layer of AlN on the substrate. As shown the buffer layer may be about 100 nm in thickness. Next a Si doped GaN layer is formed, the GaN layer may be doped with SiH 4 during epitaxial growth of the layer. A binary AlN and delta-doped AlGaN layer is then formed on top of the doped GaN layer. In one embodiment, the AlN barrier is a thin (<about 5 nm) layer. The doped AlGaN layer is formed on top of the barrier layer. In one embodiment, the doped AlGaN layer has a composition of Al x Ga 1-x N where x is about 0.2 to about 0.3. The AlGaN layer may be about 20 to 30 nm thick.
[0048] An additional embodiment of an HFET design is represented schematically in FIG. 14 . FIG. 14 depicts an embodiment of an HFET that includes an AlN/GaN superlattice charge and buffer layer. While FIG. 14 depicts a SiC substrate, it should be understood that the HFET depicted in FIG. 14 may be formed on any other type of substrate as described previously. The process of forming an HFET as depicted in FIG. 14 includes forming a buffer layer of AlN on the substrate. As shown the buffer layer may be about 100 nm in thickness. An AlN/GaN superlattice buffer layer is formed. The superlattice buffer layer includes alternate layers of undoped AlN and GaN. Each of the layers may be about 2 nm or less in thickness. Next a Si doped GaN layer is formed, the GaN layer may be doped with SiH 4 during epitaxial growth of the layer. An AlN/GaN superlattice charge layer is formed on top of the doped GaN layer. The superlattice buffer layer includes alternate layers of undoped AlN and n-type doped GaN. Each of the layers may be about 2 nm or less in thickness.
[0049] An additional embodiment of an HFET design is represented schematically in FIG. 15 . FIG. 15 depicts an embodiment of an HFET that includes an AlN barrier and delta-doped charge layer. While FIG. 15 depicts a SiC substrate, it should be understood that the HFET depicted in FIG. 15 may be formed on any other type of substrate as described previously. The process of forming an HFET as depicted in FIG. 5 includes forming a buffer layer of AlN on the substrate. As shown the buffer layer may be about 100 nm in thickness. Next a thin GaN layer is formed. A thin (<5 nm) AlN barrier layer may be formed on the GaN layer. A superlattice structure may be formed on top of the undoped GaN layer. In one embodiment, a SMASH superlattice structure is formed that includes alternating layers of undoped AlN and n-type doped AlGaN layers. Doping of the AlGaN layer occurring by introducing SiH 4 during into the reactor during the growth process. The layers are designed to create a superlattice heterobarrier that has a non-periodic structure.
[0050] The HFET device performance, particularly for high-power operation, depends on many factors, including the source and drain Ohmic contact resistance. Generally, this contact is placed upon the “top” of the AlGaN “charge layer.” In some embodiments, the AlGaN layer has been selectively removed to provide a more direct contact. For n-type GaN:Si and AlGaN:Si layers, both Ti/Al/Pt/Au and Ti/Ag/Au systems may be used to form contacts. In one embodiment, an n-type Ti/Al/Pt/Au contact scheme reproducibly shows the lowest TLM specific contact resistance using a 850C/30s anneal. These n-type Ohmic contacts have a specific contact resistance to n-type GaN:Si (n−2×10 18 cm ) of Rc<1×10 −6 Q-cm 2 . Ohmic contact resistance to undoped AlGaN (typical of the electron barrier in HFETs) is generally higher. Recently, we have identified an new Ohmic contact scheme employing vanadium-based contacts for n-type AlGaN films which may improve Ohmic contacts to high Al-composition Al x Gal 1-x N films with specific contact resistances as low as 4×10 −5 Ohm-cm 2 for x=about 0.60 films. SiN x may be used as an amorphous dielectric insulator to improve the leakage characteristics and stability of the Gate for AlGaN/GaN HFETs. This film may be deposited immediately after the growth of the AlGaN charge layer in the MOCVD reactor. This “in-situ” passivation and Gate layer may provide a stable, low-leakage dielectric film to stabilize the surface charges due to the “free AlGaN” surface. It is widely known that GaN films “dissociate” during the “cool-down” process when the wafer is exposed to elevated temperatures in an H 2 +NH 3 environment. AlGaN also degrades in the same way, albeit at a somewhat reduced rate. This process may be especially rapid near a screw or edge dislocation. A stable, amorphous SiN x film may be grown directly on the AlGaN layer-this will stabilize the AlGaN surface and inhibit the increase in leakage currents and Gate breakdown under high-stress operating conditions. The gate metal may be deposited upon this thin SiN x layer, creating an insulated gate structure. The in-situ SiN x layer may be capped with an additional plasma-enhanced chemical vapor deposition (PECVD) SiN x film in the regions between the Gate and the Source and the Gate and the Drain to improve the stability of the surfaces in these regions as well. The in-situ-deposited SiN x film may reduce the leakage contributions from these areas as well.
[0051] Cl-based inductively coupled plasma (ICP) etching may be used for the device isolation processing. This is a relatively low-damage etching process. Alternatively, wet etching with KOH solutions is known to improve the leakage current density for p-i-n diodes and may be used for device isolation etching of HFETs as well. The stability of the mesa surfaces may play a role in the operation of the device under high-power conditions.
[0052] The commonly used gate metal for an HFET is Ni/Au because it is convenient and is compatible with submicron processing. Other gate metals may be used including W or WSi.
EXAMPLE
[0053] An unpassivated delta-doped, binary barrier (D 2 B 2 ) HFET device with 0.15 μm-gate length was formed. The Al x Ga 1-x N/GaN (x≈0.2, 1.0) heterostructures of this work were grown by low-pressure metalorganic chemical vapor deposition (MOCVD) in an EMCORE TurboDisc D125 UTM high-speed rotating-disk reactor on 2.0 in. diameter 4H semi-insulating SiC substrates. The GaN epitaxial layer is grown at pressures of about 200 Torr and the AlGaN epitaxial layers are grown at about 50 Torr in a hydrogen ambient using adduct-purified trimethyl gallium (TMGa), trimethylaluminum (TMAl), and ammonia (NH 3 ). Silane (SiH 4 ) was used for the n-type dopant. The growth process begins with a high-temperature (about 1070° C.) AlN buffer layer, 100 nm in thickness. The subsequent device layers are grown at about 1050° C., beginning with 3 μm of undoped GaN. On top of this is a 1 nm AlN barrier layer, followed by a 30 nm layer of Al x Ga 1-x N (x is about 0.2). The delta doping occurs after 5 nm of growth of this last layer, with an expected Si dopant concentration >1×10 19 cm −3 (as measured by secondary ion mass spectroscopy (SIMS) analysis on similarly doped structures). Room-temperature Hall-effect measurements yield an electron mobility of 1,066 cm 2 /V−s and a sheet carrier density of 2.30×10 13 cm −2 , resulting in a large n s μ product of 2.45×10 16 /V−s. This is a large improvement over a similar structure without the barrier layer and delta doping: Hall results were 1,308 cm 2 /V−s, 1.18×10 13 cm −2 , and 1.54×10 16 V−s, for mobility, sheet charge, and n s μ product, respectively. Variable-temperature Hall-effect measurements were also performed over the temperature range from 77 K to 290 K. The sheet carrier density remained fairly constant over the measured temperature range, while the mobility steadily increased for lower temperatures, indicating that the 2DEG dominated the electrical transport characteristics.
[0054] D 2 B 2 HFET devices were then fabricated from the epitaxial heterostructures. Using chlorine as the active species, a dry etch to a depth of 250 nm was performed for device isolation. A metallization scheme consisting of Ti/Al/Ti/Au was deposited by a conventional lift-off process and rapid thermal annealed at 950° C. to obtain Ohmic contacts. From standard TLM measurements, the contact resistance was calculated to range from 0.68 to 0.87 Ohms-mm. The Ni/Au Schottky-barrier T-gate was defined by electron-beam lithography with a tri-layer resist structure (5.5% PMMA/8.5% P(MMA-MAA)/4% PMMA). HFET devices with gate lengths of 0.5 μm and 0.15 μm have been fabricated to investigate power device performance and high-frequency performance, respectively. The standard device has two parallel gate fingers, with a gate width of 75 μm. No passivation has been used for the devices reported here.
[0055] References:
[0056] The following references are hereby incorporated by reference as though fully set forth herein:
1) L. Shen, S. Heikman, B. Moran, R. Coffie, N. Q. Zhang, D. Buttari, I. P. Smorchkova, S. Keller, S. P. DenBaars and U. K. Mishra, IEEE Electron Device Lett. 22,457 (2001). 2) A. Ping, E. Piner, J. Redwing, M. Khan, and I. Adesida, Electron. Lett. 36, 175 (2000). 3) W. Lu, J. Yang, M. Khan, and I. Adesida, IEEE Trans. Elect. Dev. 48, 581 (2001). 4) K. J. Schoen, J. M. Woodall, J. A. Cooper, and M. R. Melloch, IEEE Trans. Electron. Dev. 45, 1595 (1998). 5) M. Trivedi, and K. Shenai, J. Appl. Phys. 85, 6889 (1999). 6) Q. Wahab, T. Kimoto, A. Ellison, C. Hallin, M. Tuominen, R. Yakimova, A. Henry, J. P. Bergman, and E. Janzen, Appl. Phys. Lett. 72, 445 (1998). 7) K. G. Irvire, R. Singh, M. J. Paisley, J. W. Palmour, O. Kordina, and C. H. Carter, Jr., Mat. Res. Soc. Symp. Proc. 512, 119 (1998). 8) Z. Z. Bandic, P. M. Bridger, E. C. Piqutte, T. C. McGill, R. P. Vaudo, V. M. Phanse, and J. M. Redwing, Appl. Phys. Lett. 74, 1266 (1999). 9) G. T. Dang, A. P. Zhang, F. Ren, X. A. Cao, S. J. Pearton, H. Cho, J. Han, J. I. Chyi, C. M. Lee C. C. Chuo, S. N. G. Chu, R. G. Wilson, IEEE Trans. Electron Dev. 47, 692 (2000). 10) F. Ren, A. P. Zhang, G. T. Dang, X. A. Cao, H. Cho, S. J. Pearton, J. I. Chyi, C. M. Lee, and C. C. Chuo, Sol. State Electron. 44, 619 (2000). 11) T. G. Zhu, D. J. H. Lambert, B. S. Shelton, M. M. Wong, U. Chowdhury and R. D. Dupuis, “High-Voltage GaN Vertical p-i-n Rectifier with a 2 μm-Thick i-Layer,” Electron. Lett. 36, 1971 (2000). 12) V. Tilak, B. Green, V. Kaper, H. Kim, T. Prunty, J. Smart, J. Shealy and L. Eastman, IEEE Electron Devices Lett. 22, 504 (2001) 13) Y. F. Wu, D. Kapolnek, J. P. Ibbetson, P. Parikh, B. P. Keller and U. Y. Mishra, IEEE Trans. Elect. Devices 48, 586 (2001) 14) A. T. Ping, Q. Chen, J. W. Yang, M. A. Khan and I. Adesida, IEEE Electron Device Lett. 19, 54 (1998). 15) A. Vescan, R. Dietrich, A. Wieszt, A. Schurr, H. Leier, E. L. Piner and J. M. Redwing, Elect. Lett. 36, 1234 (2000). 16) Y. F. Wu, D. Kapolnek, J. lbbetson, N. Q. Zhang, P. Parikh, B. P. Keller and U. K. Mishra, 1999 IEDM Tech. Dig., IEEE Press, Piscataway, N.J., 1999, pp. 925-927. 17) S. T. Sheppard, K. Doverspike, W. L. Pribble, S. T. Allen, J. W. Palmour, L. T. Kehias, and T. J. Jenkins, IEEE Electron. Dev. Lett. 20, 160 (1999).
[0074] In this patent, certain publications have been incorporated by reference. The text of such publications is, however, only incorporated by reference to the extent that no conflict exists between such text and the other statements and drawings set forth herein. In the event of such conflict, then any such conflicting text in such incorporated by reference publications is specifically not incorporated by reference in this patent.
[0075] While the present invention has been described with reference to particular embodiments, it will be understood that the embodiments are illustrated and that the invention scope is not so limited. Any variations, modifications, additions and improvements to the embodiments described are possible. These variations, modifications, additions and improvements may fall within the scope of the invention as detailed within the following claims. | Embodiments disclosed herein include electronic device designs based upon electronic properties of Group III-N materials and quantum-mechanical effects of specialized heterostructures. Such electronic device designs may include, for example, heterojunction field-effect transistors (HFETs) and high-electron-mobility transistors (HEMTs). The design concepts permit high power, high-frequency, and high-temperature operation of advanced electronic circuits, including devices for radar, collision-avoidance systems, and wireless communications. Designs disclosed may include one or more AlN layers and/or one or more SMASH superlattice barriers combined with one or more n-type delta-doped regions. Alternately, in certain embodiments, one or more AlN layers and one or more SMASH superlattice barriers may be combined without the n-type delta-doped regions. | 7 |
This is a division of application Ser. No. 07/024,746, filed on Mar. 11, 1987, U.S. Pat. No. 4,761,485.
BACKGROUND OF THE INVENTION
The present invention is directed to a two-step process for certain indol-2(3H)-ones (otherwise known as oxindoles, 2-oxindoles, 2-oxoindolines, or in their tautomeric form, as 2-hydroxyindoles), and to the intermediate 3,3-dibromoindol-2(3H)-ones employed in that process. Those of the present indol-2(3H)-ones which are monosubstituted on the benzene ring with (C 1 -C 3 )alkyl, (C 1 -C 3 )alkoxy or halogen are reported to have utility in the treatment of anxiety and tension (Molloy, U.S. Pat. No. 3,882,236). More particularly, all of the presently synthesized indol-2(3H)-ones are useful as intermediates in the synthesis of the analgesic/antiinflammatory 3-substituted 2-oxindole-1-carboxamides of Kadin, U.S. Pat. No. 4,556,672. Throughout the present text the products of the present invention are alternatively named as indol-2(3H)-ones (the more systematic name, based on Rigaudy et al. "IUPAC Nomenclature of Organic Chemistry", Pergammon Press, 1979, pp. 58, 172-173) and as oxindoles (a name finding common use in the literature).
Prior syntheses of present oxindoles have been reviewed, for example, by Sumpter et al., "The Chemistry of Heterocyclic Compounds", vol. 8, Weissberger, ed., Interscience Publishers, Inc., 1954, pp. 134-138; and by Livingstone, in "Rodd's Chemistry of Carbon Compounds" 2nd. Edition, vol. 4, part A, S. Coffey, ed., Elsevier Scientific Publishing Co., 1973, pp. 448-451 and in "Supplements to the 2nd Edition of Rodd's Chemistry of Carbon Compounds", vol. 4, part A, M. F. Ansell, ed., Elsevier, 1984, pp. 440-441. For the most part by far, the synthetic methods for said oxindoles reflect cyclization of suitably substituted benzene derivatives. However, Beckett et al., Tetrahedron, vol. 24, pp. 6093-6109 (1968) prepared indol-2(3H)-one itself by the hydrogenation of an acidic ethanol solution of isatin over 10% Pd/C catalyst. Michaelis, Chem. Ber., vol. 30, pp. 2809-2821 (1897) and Coleman, Ann., vol. 248, pp. 114-120 (1888) converted N-alkylindoles to N-alkyloxindoles via 3,3-dibromo-N-alkyloxindoles, using sodium hypobromite for the first step and zinc/HCl reduction for the second.
Some of the present class of 3,3-dibromoindol-2(3H)-ones are known in the literature, but are of no specified utility. These are 3,3-dibromoindol-2(3H)-one itself and corresponding 5-bromo, 5,6-dibromo, 5,7-dibromo and 4,7-dimethoxy analogs; Sumpter et al., J. Am. Chem. Soc., vol. 67, pp. 1656-1657 (1945); DaSettimo, J. Org. Chem., vol. 39, pp. 1995-1998 (1974); and Parrick et al., Tetrahedron Lett., vol. 25, pp. 3099-3100 (1984). The earliest reference obtained these 3,3-dibromoccompounds from the desired oxindole; the intermediate one by bromination of 2,3-dibromoindoles; and the latest by the action of N-bromosuccinimide (not pyridinium perbromide) on indoles or 3-bromoindoles.
SUMMARY OF THE INVENTION
The present invention is directed to a process for the preparation of an oxindole of the formula ##STR1## wherein X and Y are each independently hydrogen, (C 1 -C 3 )alkyl, (C 1 -C 3 )alkoxy, fluoro, chloro or bromo, which comprises the sequential steps of
(a) reacting an indole of the formula ##STR2## with substantially 3 molar equivalents of pyridinium bromide perbromide in a reaction-inert solvent to yield an intermediate dibromooxindole of the formula ##STR3## and either (b 1 ) hydrogenating said dibromooxindole over a noble metal catalyst in a reaction-inert solvent to yield said oxindole of the formula (I); or
(b 2 ) debrominating said dibromooxindole with zinc dust in a lower aliphatic carboxylic acid to yield said oxindole of the formula (I).
As used above and elsewhere herein, the expression "reaction-inert solvent" refers to a solvent which does not significantly reduce the yield of the desired product by interaction with the starting materials, reagents, intermediates or products. The expression "lower aliphatic carboxylic acid" refers to a straight or branched chain (C 2 -C 6 )alkanoic acid.
When step (b 1 ) is employed, the preferred noble metal catalyst is palladium, more preferably palladium supported on carbon, most preferably using ethanol as solvent. When step (b 2 ) is employed, the preferred carboxylic acid is acetic acid. In any case, the preferred solvent in step (a) is t-butanol.
It is particularly advantageous to carry out the present process on commercially available 5-chlorindole, producing 5-chloroindol-2(3H)-one, an intermediate for Kadin's particularly valuable 5-chloro-3-(2-thenoyl)-2-oxindole-l-carboxamide (Kadin, loc. cit.).
The present invention is also directed to the intermediate compounds of the formula (III), excluding the prior known compounds of this class which are listed above.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is readily carried out. In the first step, the indole of the formula (II) is treated with substantially 3 molar equivalents of pyridinium bromide perbromide in a reaction inert solvent. t-Butanol is the preferred solvent for this purpose. The temperature is not critical. For example, temperatures in the range of 0°-50° C. are generally satisfactory. Ambient temperatures, e.g., 17°-30° C. avoiding the cost of external heating or cooling, are most convenient. The resulting 3,3-dibromo intermediate, of the formula III, is isolated by standard methods of solvent evaporation, extraction, crystallization and chromatography.
The second step didebromination to form the indol-2(3H)-one (oxindole) of the formula (I) is optionally carried out by hydrogenation over a noble metal catalyst in a reaction-inert solvent. The noble metal catalysts employed in the present invention include platinum, palladium, rhodium and ruthenium, either of the supported or non-supported type, as well as the known catalytic compounds thereof such as the oxides, chlorides, etc. Examples of suitable catalyst supports include carbon, silica, calcium carbonate and barium sulfate. The catalysts may be performed or formed in situ by prereduction of an appropriate salt of the catalytic compound. The preferred noble metal in the present case is palladium. Most preferred is 5-10% palladium supported on carbon. The temperature of the present hydrogenation is not critical, temperatures in the range 0°-60° C. being generally satisfactory. Ambient temperatures, for the reasons stated above in the halogenation step, are most convenient. Likewise, hydrogenation pressure is not critical, pressures in the range of 1-100 atmospheres being generally satisfactory. However, to avoid the undue expense of high pressure equipment, pressures in the range of 1 to about 10 atmospheres are preferred. Once hydrogenolysis of the 3,3-dibromo groups is complete, the valuable catalyst is generally recovered by filtration and recycled in the hydrogenation if still active, or reprocessed to recover to the noble metal and/or convert it to fresh catalyst. The desired oxindole is then recovered from catalyst mother liquors and purified by standard methods of concentration, extraction and crystallization.
Alternatively, the second step didebromination to form the indol-2(3H)-one of the formula (I) is carried out by the action of zinc in a lower aliphatic carboxylic acid, preferably acetic acid. Again, temperature is not critical, temperatures in the range 0°-50° C. being generally satisfactory, and ambient temperatures most convenient and least costly.
Many of the indoles required for the present synthesis of indol-2(3H)-ones are available commercially. For example, indole, 5-bromoindole, 4-, 5- and 6-chloroindoles, 5-fluoroindole, 4-, 5-, 6- and 7-methylindoles, 4- and 5-methoxyindoles and 5,6-dimethoxyindole are available from Aldrich Chemical Co., Inc., 940 West Saint Paul Avenue, Milwaukee, Wisconsin 53233, U.S.A. Those for which a commercial source is not identified are available by one or more of an estensive number of literature methods, as summarized, for example in "Rodd's Chemistry of Carbon Compounds", 2nd Edition, S. Coffey, editor, Volume IVA, Elsevier Scientific Publishing Co., 1973, pp. 397-405; Sundberg, "Comprehensive Heterocyclic Chemistry", vol. 4, Katritzky et al., eds., Pergammon Press, 1984, pp. 313-369; and Sumpter et al., "The Chemistry of Heterocyclic Compounds", vol. 8, Weissberger, ed., Interscience Publishers, Inc., 1954, pp. 3-23.
The present invention is illustrated by the following examples, but not limited to the specific details thereof.
EXAMPLE 1
3,3-Dibromo-5-chloroindol-2(3H)-one
To a solution of 5-chloroindole (1.00 g) in t-butanol (65 ml) was added portionwise over 0.5 hr 6.9 g of pyridinium bromide perbromide. The reaction mixture was stirred at room temperature for 2 hours after which TLC analysis (1:1 ethyl acetate/hexane) indicated complete conversion of starting material to several products. The reaction mixture was diluted with ethyl acetate (400 ml) and H 2 O (400 ml). The organic layer was separated and the aqueous layer extracted with ethyl acetate (300 ml). The combined organic extracts were washed with H 2 O (2×400 ml) and brine, dried (Na 2 SO 4 ) and concentrated in vacuo to a yellow-green oil. Purification on a silica gel column eluted with 40% ethyl acetate/hexane afforded the more polar product (3,3-dibromo-5-chlorooxindole) as a brown solid (1.26 g, 60%).
In like manner, indole and 4-, 5- and 6-chloro-, 5-fluoro, 4-, 5-, 6- and 7-methyl, 4- and 5-methoxyand 5,6-dimethoxy-indoles are converted to indole-2(3H)-one and corresponding substituted indol-2(3H)-ones, respectively.
EXAMPLE 2
5-Chloroindol-2(3H)-one
(5-Chloro-2-Oxinole)
Method A
A mixture of title product of the preceding Example (1.28 g) in absolute ethanol (100 ml) was hydrogenated at 5 psi in the presence of 10% palladium on carbon (800 mg). After 20 minutes TLC analysis (10% ethyl acetate/CH 2 Cl 2 ) indicated complete conversion of starting material to a single more polar product. The reaction mixture was filtered over diatomaceous earth, the filter cake washed with ethanol and then methanol, and the filtrate concentrated in vacuo to a tan solid (870 mg). Purification on a silica gel column eluted with 5% CH 3 OH/CH 2 Cl 2 afforded 520 mg (79%) of title product, mp=196°-198° C. (lit. mp=195°-196° C.; Can. J. Chem. vol. 41, 2399, 1963).
Method B
To a solution of title product of the preceding Example (1.5 g) in glacial acetic acid (40 ml) was added 3.02 g (10 equiv.) of zinc dust (325 mesh). The reaction mixture, which turned slightly exothermic, was stirred at room temperature. TLC analysis (5% CH 3 OH/CH 2 Cl 2 ) after 0.5 hr indicated complete conversion of starting material to the more polar product. The reaction mixture was filtered, washed well with ethyl acetate, and the filtrate concentrated in vacuo to a light tan semisolid. This was redissolved in ethyl acetate (200 ml), washed with H 2 O (2x) and brine (1x), dried over Na 2 SO 4 , and concentrated in vacuo to give 0.77 g of light tan crystalline product.
Recrystallization from 30 ml ethanol afforded 0.57 g of purified title product, mp=196°-198° C., identical to the product of Method A.
By the same alternative methods, the other products of the preceding Example are converted to indol-2(3H)-one and corresponding indol-2(3H)-ones substituted on the aromatic ring. | A two-step process for the synthesis of certain indol-2(3H)-ones from indoles, and the 3,3-dibromoindol-2-(3H)-ones which are intermediates in that process. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Application No. 60/840,127, filed Aug. 25, 2006.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
This work was supported by the Institutional ACS (USA) Grant IRG-02-197-01. The United States Government may have certain rights in this invention.
BACKGROUND OF THE INVENTION
The standard treatment for metastatic renal cell carcinoma (RCC) includes cytokine therapy with interferon-alpha (IFN-α) or interleukin-2 (IL2), which produce 15-20% response rates. These modest response rates highlight the need for more effective treatments; however, they also indicate that RCC is immunoresponsive. An effective tumor vaccine targets antigens that are highly expressed on tumor cells. Recombinant heat shock proteins (HSP) can be used to stimulate the immune system to target tumor-specific antigens, leading to tumor killing. HSP are one of the most abundant proteins found inside a cell. They have the ability to bind and protect intracellular proteins in the presence of cellular stress, such as heat and glucose depravation.
Recombinant HSP, such as hsp100 and grp170, can be complexed to a tumor-specific antigen. Depending on the tumor antigen, the HSP-target antigen complex forms at room temperature or when heated. The complex is then administered as a vaccine that targets the tumor.
Heat shock proteins (HSP) are some of the most abundant intracellular proteins. They normally function as molecular chaperones, assisting with protein folding and formation of multi-subunit complexes. They are induced by cellular stress and protect intracellular proteins by binding and preventing denaturation. HSP are broadly categorized as hsps (designated here using small characters) or glucose regulated proteins (grps) based on their subcellular localization and the stressors that induce their expression ((Shen, J. et al., Coinduction of glucose-regulated proteins and doxorubicin resistance in Chinese hamster cells. Proc Natl Acad Sci USA 84, 3278-82 (1987)) ((Srivastava, P., Roles of heat-shock proteins in innate and adaptive immunity. Nat Rev Immunol 2, 185-94 (2002)). For example, hsps (families of hsps: small hsps, hsp40, calreticulin, hsp60, hsp70, hsp90, hsp110) are induced by heat and oxidizing agents, and localize to the nucleus, cytoplasm and mitochondria. Grps (family of grps: grp78, grp94, grp170) are induced by hypoxia and glucose deprivation, and localize to the endoplasmic reticulum.
Experiments performed in the early 1900s demonstrated that tumor cells and lysates can protect mice against subsequent tumor challenges. Follow up experiments using tumor fractions identified HSP as the “active ingredient” providing immune protection (Udono, H. & Srivastava, P. K., Comparison of tumor-specific immunogenicities of stress-induced proteins gp96, hsp90, and hsp70. J Immunol 152, 5398-403 (1994)). The HSP may be promiscuously bound to a number of tumor antigens, which may produce a tumor-specific immune response; although, it is not yet possible to specifically predict with any certainty that that such a response will in fact occur with a particular HSP bound to a particular antigen without actual tests (Castelli, C. et al. Human heat shock protein 70 peptide complexes specifically activate antimelanoma T cells. Cancer Res 61, 222-7 (2001)).
It has been postulated that HSP found outside a cell are recognized as a danger signal, indicating to the immune system the presence of damaged or diseased tissue. Receptors for HSP have been identified on dendritic cells (DC), which are professional antigen presenting cells (APC). Using solubilized APC membrane applied to a gp96 affinity column, CD91 was identified as a receptor for HSP; CD91 binds hsp90, hsp70 and calreticulin. Various scavenger receptors including CD14, TLR-2 and TLR4 have been shown to bind and internalize hsp70 and hsp60. The binding of HSP and DC leads to NF-κB signaling, which has previously been shown to regulate cytokines and DC maturation.
In certain cases, microgram quantities of HSP bound to peptides may serve as a powerful immune adjuvant, activating both an antigen-specific and an innate immune response. While the majority of exogenous antigens produce a MHC class II response, proteins and peptides bound to HSP may elicit a MHC class I mediated CD8+ T cell response as well as a MHC class II response (Udono, H., Levey, D. L. & Srivastava, P. K., Cellular requirements for tumor-specific immunity elicited by heat shock proteins: tumor rejection antigen gp96 primes CD8+ T cells in vivo. Proc Natl Acad Sci USA 91, 3077-81 (1994)) (Matsutake, T. & Srivastava, P. K., The immunoprotective MHC II epitope of a chemically induced tumor harbors a unique mutation in a ribosomal protein. Proc Natl Acad Sci USA 98, 3992-7 (2001)). The mechanism of cross presentation is the subject of active research; however, it known that cross presentation of peptides bound to HSP requires functional proteosomes and transporter associated with antigen processing (TAP). HSP uncomplexed to peptide might stimulate an innate immune response by stimulating the secretion of various cytokines including, TNFα, IL-1α, IL-6, IL-12, and GM-CSF (Basu, S., Binder, R. J., Suto, R., Anderson, K. M. & Srivastava, P. K., Necrotic but not apoptotic cell death releases heat shock proteins, which deliver a partial maturation signal to dendritic cells and activate the NF-kappa B pathway. Int Immunol 12, 1539-46 (2000).) (Kol, A., Lichtman, A. H., Finberg, R. W., Libby, P. & Kurt-Jones, E. A., Cutting edge: heat shock protein (HSP) 60 activates the innate immune response: CD14 is an essential receptor for HSP60 activation of mononuclear cells. J Immunol 164, 13-7 (2000)). Both the antigen-specific and the innate immune responses contribute to the final anti-tumor effect.
HSP vaccine strategies have been reported by others. HSPs are complexed to a wide spectrum of intracellular tumor proteins. It is therefore possible to isolate these HSPs and administer them as a tumor-specific, autologous vaccine. In principle, this approach is similar to using tumor lysate as a vaccine; however, the extraction of tumor HSPs produces a more concentrated vaccine enriched for the “active ingredient”. Using this approach, a phase III clinical trial for metastatic melanoma and a phase III adjuvant therapy trial for kidney cancer have completed enrollment. In two different phase II trials for metastatic kidney cancer, approximately 35% of patients had a clinical response. No significant toxicities were observed, and no autoimmune effects were noted (Amato, R. et al. in ASCO A1782 (2000)) (Assikis, V. J. et al. in ASCO A1552 (2003)).
There unfortunately are limitations to using tumor derived HSPs. Surgically obtained tumor tissue is not available for all patients. Even when tumor tissue is available, a vaccine can not be prepared in approximately 10% of cases. Finally, only a small fraction of relevant tumor peptides in the vaccine produce an antitumor effect. Therefore, in an effort to produce a highly concentrated vaccine against a known tumor antigen, genetically engineered proteins consisting of HSP fused to the C or N terminus of a tumor protein were synthesized (Udono, H., Yamano, T., Kawabata, Y., Ueda, M. & Yui, K., Generation of cytotoxic T lymphocytes by MHC class I ligands fused to heat shock cognate protein 70. Int Immunol 13, 1233-42 (2001)) (Suzue, K., Zhou, X., Eisen, H. N. & Young, R. A., Heat shock fusion proteins as vehicles for antigen delivery into the major histocompatibility complex class I presentation pathway. Proc Natl Acad Sci U S A 94, 13146-51 (1997)) (Anthony, L. S. et al., Priming of CD8+ CTL effector cells in mice by immunization with a stress protein-influenza virus nucleoprotein fusion molecule. Vaccine 17, 373-83 (1999)). In most cases the HSP is of microbial origin and can itself produce an immune response. Although an unlimited supply of vaccine can be produced, this approach does not produce an immune response in all cases. A HPV 16-E7 (cervical cancer antigen)-hsp110 fusion vaccine was, for example, created that did not produce a CD8+ CTL response in vivo (unpublished data). A possible explanation for this negative result is that a fusion protein is an unnatural construct and interactions with APC depend on proper positioning and steric changes associated with noncovalent complexing of HSP and tumor antigen.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a Coomassie blue-gel staining of whole cell lysate (center 2 lanes) and purified recombinant CA9 (right lane). CA9 cDNA was subcloned into the pRSETA vector. The plasmid was transformed into Escherichia coli cells and the protein was purified using a nickel nitriloacetic acid-agarose column.
FIG. 2 is a gel showing that HSP binds CA9 at 45° and 55° C., but not at room temperature (RT). The hsp110-CA9 complex was immunoprecipitated using anti-hsp110 antibody. After SDS-PAGE (10%) electrophoresis, a western blot analysis was performed using anti-His antibody.
FIG. 3 is a bar graph showing that immunization with hsp110-CA9 complex elicits CA9-specific immune responses measured using an ELISPOT assay. Balb/c mice (3 mice/group) were immunized intradermally (i.d.) with PBS, CA9, or hsp110-CA9 complex. The splenocytes were harvested 10 d after 2 immunizations performed 10 days apart. IFN-γ spots were counted using the KS Elispot System (version 4.3.56) from Zeiss Microscopy.
FIG. 4 is a line graph showing that immunization with hsp110-CA9 complex elicits CA9-specific humoral response measured using ELISA. Balb/c mice (3 mice/group) were immunized intradermally (i.d.) with PBS, CA9, or hsp110-CA9 complex. Five-fold serial dilutions of blood were tested for CA9 specific antibodies using CA9 coated microtiter plates (10 μg/ml).
FIG. 5A . is a graph showing essentially no antitumor effect when 2×10 5 RENCA-CA9 tumor cells were injected subcutaneously 7 days after 3 immunizations with PBS administered 14 days apart (control; A)
FIG. 5B is a graph showing significant antitumor effect when 2×10 5 RENCA-CA9 tumor cells were injected subcutaneously 7 days after 3 immunizations with hsp110-CA9 (B) administered 14 days apart. Each line represents tumor growth in a single mouse. Immunization with hsp110-CA9 has an antitumor effect.
BRIEF DESCRIPTION OF THE INVENTION
Carbonic anhydrase IX (CA9) has been identified recently as a potential target for immunotherapy. CA9 is present in 95-100% of clear renal carcinoma cells (RCC) and it is not present in normal, nonmucosal tissue. We have now found that HSP proteins, normally found inside a cell, are powerful immune activators when found outside a cell that are capable of stimulating an immune response against proteins complexed to the HSP.
DETAILED DESCRIPTION OF THE INVENTION
We have now demonstrated in an animal model that recombinant CA9 complexed to HSP can serve as an effective RCC vaccine.
As an example, in accordance with the invention, mouse hsp110 was cloned into pBacPAK-his vector (BD Biosciences Clontech, Palo Alto, Calif.) and expressed using a BacPAK baculovirus system using methods known to those skilled in the art. A known CA9 cDNA in accordance with the present invention was subcloned into the pRSETA vector (Invitrogen, Carlsbad, Calif.). The plasmid was transformed into Escherichia coli JM109 (DE3) cells and protein was purified ( FIG. 1 ) using a nickel nitriloacetic acid-agarose column (Qiagen, Valencia, Calif.). Renal carcinoma (RENCA) cells, which are syngeneic with BALB/c mice, are used for the murine studies. RENCA does not normally express CA9, thus RENCA cells stably transduced by known methods to express human CA9 (RENCA-CA9) were obtained and used.
Preliminary data from our laboratory demonstrates that a HSP based vaccine can produce a CA9 specific immune response in vivo. HSP is capable of binding partially denatured protein, and preventing further protein denaturation and aggregation. It is possible to take advantage of this feature by heat shock complexing HSP and CA9 in vitro ( FIG. 2 ). This complex can then be administered as a vaccine. In a mouse model, the HSP/CA9 complex administered intradermally (i.d.) led to cross presentation and generated a CA9 specific cytotoxic T-lymphocyte (CTL) response measured using an Elispot assay ( FIG. 3 ). Vaccination with HSP/CA9 complex also produced a humoral response and generated CA9 specific antibodies ( FIG. 4 ). Our data demonstrates that vaccination with HSP/CA9 complex in a murine model produces an antitumor effect ( FIG. 5 ).
The vaccine strategy described here takes advantage of the in vivo function of HSP for use in a kidney cancer vaccine, and was first proposed by John Subjeck's group (Manjili, M. H. et al., Cancer immunotherapy: stress proteins and hyperthermia. Int J Hyperthermia 18, 506-20 (2002)) (Manjili, M. H. et al., Development of a recombinant HSP110-HER-2/neu vaccine using the chaperoning properties of HSP110. Cancer Res 62, 1737-42 (2002)) (Wang, X. Y. et al., Targeted immunotherapy using reconstituted chaperone complexes of heat shock protein 110 and melanoma-associated antigen gp100. Cancer Res 63, 2553-60 (2003)). Recombinant HSP and a target tumor protein/antigen can be combined at room temperature or heat shocked in vitro to produce a noncovalent complex. The temperature (amount of heat) necessary for forming a “chaperone complex” of HSP110 with a protein antigen depends on the antigen. Different antigens/proteins have different melting temperatures. This complex provides the same danger signal provided by intracellular HSP released in various disease states associated with cellular damage. Advantages include the following:
1) This preparation is a highly concentrated vaccine directed at a known tumor target. 2) This preparation can be produced in unlimited quantity. 3) This preparation has the potential to be effective against all tumors expressing the target. 4) If the full length protein is used, the vaccine can be used in all patients, regardless of HLA restrictions. 5) There are currently no immune adjuvants approved for human use that are effective in stimulating a cell-mediate immune response. The only immune adjuvants currently approved for human use are aluminum, calcium phosphate, and a squalene formulation, which effectively stimulate a humoral response, but are poor stimulants of a cellular response (Binder, R. J., Anderson, K. M., Basu, S. & Srivastava, P. K., Cutting edge: heat shock protein gp96 induces maturation and migration of CD11c+ cells in vivo. J Immunol 165, 6029-35 (2000)).
The following specific examples serve to illustrate and not limit the present invention:
Mice and Cell Lines
6-8 week old female BALB/c mice were purchased from the NCI (Frederick, Md.) and housed under pathogen-free conditions. Parental RENCA cells and RENCA cells stably transduced to express human CA9 (RENCA-CA9) were provided by Dr. Arie Belldegrun (University of California, Los Angeles). CA9 expression in RENCA-CA9 was confirmed using western blot and monoclonal antibody against CA9, obtained from Dr. Egbert Oosterwijk (University Hospital of Nijmegen, Nijmegen, Netherlands). The RENCA lines were maintained in RPMI 1640, 10% heat-inactivated fetal calf serum, 1% glutamine, 1% nonessential amino acids, 1% sodium pyruvate, 1% penicillin/streptomycin, and 1% HEPES buffer.
Expression and Purification of Recombinant Proteins
Mouse Hsp110 and human CA9 cDNA (obtained from Dr. Belldegrun) were cloned into pBacPAK-his vector (BD Biosciences Clontech, Palo Alto, Calif.), transformed into monolayer Sf21 cells using replication defective virus, and expressed using the BacPAK baculovirus system. Proteins were purified using a nickel nitriloacetic acid-agarose column (Qiagen, Valencia, Calif.). Protein concentrations were measured using a Protein Assay Kit (Bio-Rad, Hercules, Calif.). Protein purity was assessed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Coomassie Blue staining. Endotoxin levels in recombinant proteins were assessed using a Limulus Amebocyte lysate kit (Biowhittaker, Walkersville, Md.) and noted to be 10-25 endotoxin units/ng protein.
Reconstitution of Heat Shock Protein and Antigen Complex
Recombinant hsp110 and CA9 were complexed at 1:1 molar ratio and incubated for 30 minutes at room temperature (RT) or at heat shock temperatures of 45 or 55 degrees Celsius. It is understood that similar results can be obtained at comparable molar ratios, e.g. about 0.8:1 to about 1:0.8. The complex was immunoprecipitated using anti-hsp110 antibody to verify noncovalent binding between hsp110 and CA9. After SDS-PAGE (10%) electrophoresis, western blot analysis was performed using anti-His antibody (Amersham, Piscataway, N.J.). For the in vivo studies, hsp110 and CA9 were complexed at RT. CA9 peptide (A Y E Q L L S R L) was ordered from Alpha Diagnostics (San Antonio, Tex.) and similarly complexed to hsp110.
Construction of DNA Vaccine
A DNA vaccine consisting of pcDNA3.1 vector (Invitrogen, Carlsbad, Calif.) carrying CA9 fused to the N terminus of grp170 was constructed. Control vaccines included pcDNA3.1 carrying CA9 alone or grp170 alone. All genes were inserted behind a CMV promoter and sequence was verified. Protein expression was verified in transfected COS cells.
Tumor Prevention Study
For the tumor prevention studies, mice (5 per group) were immunized 3 times, 14 days apart, with 100 μl of vaccine. 7 days after the last immunization, 2×105 RENCA-CA9 cells were injected intradermally. Tumor growth ((shortest diameter2×longest diameter)/2) was monitored every 2 days using an electronic caliper. The complete set of experiments was repeated 3 times. The vaccination groups for the protein vaccines included PBS (control), CA9 (25 μg) alone, hsp110 (50 μg) alone, CA9 (25 μg)+50 μl Freud's Adjuvant (CA9+FA), and hsp110 complexed to CA9 (hsp110+CA9; 75 μg). The vaccination groups for the CA9 peptide-based vaccines included PBS (control), CA9 peptide (50 μg), hsp110 complexed to CA9 peptide (hsp110+CA9 peptide; 100 μg). The vaccination groups for the DNA vaccine included pcDNA3.1 carrying CA9 (10 μg) alone, grp170 (10 μg) alone, and CA9-grp170 (10 μg). CA9+FA vaccine was injected subcutaneously and all other vaccines were injected intradermally.
Tumor Treatment Study
This study was similar to the tumor prevention assay except that mice were injected intradermally with 2×105 RENCA-CA9 cells and after tumor implantation the vaccines were injected on days 3, 9, and 14 after tumor implantation. Tumor growth was monitored as previously described.
ELISPOT
Splenocytes were harvested 2 weeks after immunization and stimulated in vitro with irradiated RENCA-CA9 for 5 days. Filtration plates (Millipore, Bedford, Mass.) were coated with 10 μg/ml rat antimouse IFN-γ (clone R4-6A2; PharMingen, San Diego, Calif.) at 4° C. overnight, washed and blocked. Splenocytes (5×105/well) were incubated with CA9 (20 μg/ml) at 37° C. for 24 hours, then washed. A biotinylated IFN-γ antibody (5 μg/ml; clone XMG1.2; PharMingen), avidin-alkaline phosphatase D (0.2 unit/ml; Vector Labs, Burlingame, Calif.) and 5-bromo-4-chloro-3-indolyl phosphate/nitroblue tetrazolium (Boehringer Mannheim, Indianapolis, Ind.) were used to detect IFN-γ secretion. IFN-γ spots were counted using the KS Elispot System (version 4.3.56) from Zeiss Microscopy.
ELISA
Five-fold serial dilutions starting at 1:200 of serial bleedings from immunized mice were tested for CA9-specific antibodies using CA9 coated microtiter plates (10 μg/ml). Antibodies were detected using biotinylated anti-mouse IgG1 or IgG2a, avidin-alkaline phosphatase D (0.2 unit/ml; Vector Labs) and 5-bromo-4-chloro-3-indolyl phosphate/nitroblue tetrazolium (Boehringer Mannheim). Binding specificity was assessed by testing the sera using a control protein coated on the microtiter plates and by testing preimmune sera. Optical densities (OD) were read at 450 nm in a Titertek Multiscan MCC/340 plate scanner. For ELISA assays, the OD at 450 nm and 1:200 dilution is reported.
Statistical Analysis
Differences in tumor growth were assessed by repeating measure ANOVA. A p-value <0.05 was considered significant. All statistical analysis was performed using Stata 8.0 (College Station, Tex.).
Results
Hsp110 binds CA9 in vitro. Recombinant hsp110 and CA9 were combined at 1:1 molar ratio and noncovalent binding was confirmed by immunoprecipitating the complex using anti-hsp110 antibody ( FIG. 2 ). After SDS-PAGE (10%) electrophoresis, western blot analysis was performed using anti-His antibody. HSP binds CA9 at room temperature, and binding increases at 45° and 55° C.
Hsp110+CA9 was evaluated as a tumor vaccine in a RENCA murine model. In a tumor prevention assay, BALB/c mice were immunized prior to injection of RENCA-CA9. Hsp110+CA9 prevented tumor growth in all animals. Although both CA9 alone and hsp110 alone decreased tumor growth, the effect was not statistically significant when compared to the control group that was immunized with PBS. When the mice challenged with RENCA-CA9 were observed for 40 days, none of the mice immunized with hsp110+CA9 developed tumors ( FIG. 3 ). At 40 days, one of 5 mice immunized with hsp110 was tumor free. All other mice developed palpable tumors at the site of tumor injection.
Immunization with hsp110+CA9 produced both cellular and humoral immune responses. Hsp110+CA9 generated a CA9-specific cytotoxic T-lymphocyte (CTL) response measured using Elispot assay. CA9 alone and CA9 with complete FA produced lesser CTL responses. Vaccination with hsp110+CA9 also produced CA9 specific antibodies as measured by Elisa assay ( FIG. 4 b ).
Alternative heat shock protein based tumor vaccine targeting CA9 were evaluated. A vaccine consisting of hsp110 complexed to an immunodominant CA9 peptide decreased growth of RENCA-CA9 in a tumor prevention assay. Hsp110+CA9 peptide vaccination generated CA9 specific CTLs, but produced no CA9 specific antibodies. A DNA vaccine consisting of pcDNA3.1 vector carrying CA9 fused to the N terminus of grp170 produced no antitumor effects in a tumor prevention assay. The vaccine produced no CA9 specific CTLs or CA9 specific antibodies.
Hsp110+CA9 is effective against established RENCA tumors. Of the 3 vaccine strategies evaluated, a complex of recombinant hsp110 and CA9 produced the most effect antitumor effect. Therefore, the vaccine employing full length proteins was evaluated in a tumor treatment assay. Balb/c mice were first injected intradermally with RENCA-CA9 to establish palpable tumors prior to treatment. Immunization with hsp110+CA9 significantly decreased tumor growth when compared to immunization with PBS. CA9 alone decreased tumor growth; however, the difference when compared to the PBS control did not reach statistical significance.
The most common histologic subtype of RCC is the clear cell variant. Von Hippel-Lindau (VHL) mutations and deletions are found in over 50% of sporadic clear cell RCCs.(18, 19) Hypermethylation represents an additional mechanism for VHL inactivation(19, 20). In clear cell RCC the overexpression of CA9 is the direct consequence of the defect in VHL function, which normally functions to degrade and suppress HIF-1α. CA9 expression is positively regulated by HIF-1α. Therefore, in the majority of clear cell RCCs, both HIF-1α and CA9 are constitutively expressed and no longer regulated by oxygen tension. CA9 expression is found in 95% of clear cell renal tumors with no expression in normal kidney. Expression in other normal tissue is limited to basal cells of hair follicles, gonadal epithelium, choroid plexus, and some gastrointestinal mucosa
HSPs normally function as molecular chaperones, assisting with protein folding and formation of multi-subunit complexes. Experiments performed in the early 1900s demonstrated that tumor cells and lysates can protect mice against subsequent tumor challenges. Followup experiments using tumor fractions identified HSPs as the “active ingredient” providing immune protection. The HSPs are promiscuously bound to a large repertoire of tumor antigens, which produces a tumor-specific immune response. It is therefore possible to isolate these HSPs and administer them as a tumor-specific, autologous vaccine. Using this approach, a phase III clinical trial for metastatic melanoma and a phase III adjuvant therapy trial for kidney cancer have completed enrollment. In two different phase II trials for metastatic kidney cancer, approximately 35% of patients had a clinical response. No significant toxicities were observed, and no autoimmune effects were noted.
There are limitations to using tumor derived HSPs. Surgically obtained tumor tissue is not available for all patients. Even when tumor tissue is available, a vaccine can not be prepared in approximately 10% of cases. Finally, only a small fraction of relevant tumor peptides in the vaccine produce an antitumor effect. Recombinant HSP and a target tumor protein can be combined in vitro to produce a noncovalent complex. This complex provides the same danger signal provided by intracellular HSPs released in various disease states associated with cellular damage. Advantages to this approach include the following:
1) This preparation is a highly concentrated vaccine directed at a known tumor target. 2) This preparation is produced in unlimited quantity. 3) Although this vaccine would not be patient specific, it has the potential to be effective against all tumors expressing the target. 4) By using the full length protein, the vaccine can be used in all patients, regardless of HLA restrictions.
In this study, three HSP based tumor vaccines targeting CA9 were evaluated. All three strategies were screening using an in vivo tumor prevention model where vaccination was followed by tumor challenge. A vaccine using full-length, recombinant CA9 and hsp110 was most effect in preventing tumor growth, and produced robust cellular and humoral immune responses. A vaccine combining hsp110 and an immunodominant CA9 peptide also prevented tumor growth. As expected, a peptide based vaccine produced a cellular response but no humoral response. More effective antitumor effects may be possible with use of additional immunodominant peptides.
The final vaccine strategy evaluated was a DNA vaccine. A DNA vaccine obviates the technical challenges associated with production of recombinant proteins. However, a plasmid vector designed to express grp170 linked to CA9 had no antitumor effects and failed to produce a cellular or humor immune response. In unpublished work from our laboratory, a plasmid vector linking hsp110 and HPV 16-E7 was not effective as a tumor vaccine in a murine, cervical cancer model. Therefore, in the present study, a plasmid containing grp170 was constructed. Both large members of the hsp70 superfamily failed to produce an immune response against the linked antigen. A possible explanation is that a fusion protein is an unnatural construct and interactions with APCs depend on proper positioning and steric changes associated with noncovalent complexing of HSP and tumor antigen.
A tumor prevention model is analogous to the clinical setting in which adjuvant therapy is utilized. Adjuvant therapy is provided to patients at high risk for recurrence following resection of clinically localized RCC. These patients have no radiographically detectable disease following surgery, and the goal of adjuvant therapy is to prevent disease recurrence. This study suggests that a HSP based tumor vaccine targeting CA9 may be an effective adjuvant therapy. This vaccine strategy may also be effective in the treatment of metastatic RCC. To explore this possibility, the vaccine strategy shown to be most effective in the tumor prevention model was tested in a tumor treatment model where vaccine was administered after palpable, intradermal tumors were established. The recombinant protein vaccine combining hsp110 and CA9 was effective in decreasing the growth of established tumor.
In an animal model, recombinant hsp110 complexed to CA9 is an effective treatment for RCC, and produces a more effective antitumor effect than HSP-based strategies utilizing CA9 peptide or plasmid construct. | A heat shock protein in combination with carbonic anhydrase IX and a method for improving immune response to carbonic anhydrase IX in a mammal by complexing it with a heat shock protein prior to administration to the mammal. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of our earlier filed U.S. patent application Ser. No. 08/051,413 filed Apr. 23, 1993 and now U.S. Pat. No. 5,340,745 issued Aug. 23, 1994, and which in turn is a Continuation-in-Part of Ser. No. 07/833,182 filed Feb. 10, 1992 and now abandoned.
FIELD OF INVENTION
This invention relates to a method for determining rates of reaction in a chemical reactor system.
BACKGROUND OF INVENTION
The acquisition of kinetic data from a chemical reaction system is usually a laborious, time consuming and expensive undertaking. As a consequence, evaluation of catalysts and reaction conditions, in the chemical industry, for example, is often carried out with scanty data which does not allow for a full understanding of the system under study. Conventional methods generally include collecting iso-thermal conversion data at steady state for a number of feed rates. Because of operating requirements, such as waiting for steady state, start-up, shutdown etc., it is usually only possible to make 1-5 runs per day in any given system. At least 30 runs are needed over a range of 3 or 4 temperatures. About 8-10 space velocities are required at each temperature, and hence it will be seen that such a study will take about two months to complete. This time period may be considerably increased if repeat runs are required to verify catalyst stability over this length of time or to obtain a statistical measure of variance or if feed composition of reactant concentration are to be varied. Frequently, therefore, there may be as much as one person-year required for a full research study. There is, therefore, a considerable need for an improved method of acquiring kinetic rate data for chemical reactors.
OBJECT OF THE INVENTION
An object of the present invention is to provide a method for determining kinetic rate data for chemical reactors which is at least an order of magnitude faster than conventional methods.
BRIEF STATEMENT OF INVENTION
Thus, by one aspect of this invention there is provided a method for rapid collection of kinetic rate data from a temperature scanning reactor in which a feed stock is reacted under non-steady state thermal conditions to form a conversion product and which method comprises,
ramping the temperature of said feed stock over a selected range of temperature,
continuously monitoring conversion and temperature data of said feed stock and said conversion product while changing temperature in said reactor and determining therefrom a reaction rate which is representative of steady-state conditions said data is obtained during said non-steady state operation of the reactor.
By another aspect of this invention there is provided a method for obtaining kinetic data from a batch reactor, a continuous stirred tank reactor, a stream swept reactor and a plug flow reactor.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a graph showing constant rate curves of methanol formation;
FIG. 2 is a graph showing methanol conversion versus rate -1 ;
FIG. 3 is a graph showing methanol conversion versus input temperature T i at three constant space velocities or space times; WHSV=0.1 (r=10); WHSV=1.1 (r=0.91) and WHSV=2.1 (r=0.48);
FIG. 4 is a graph showing methanol conversion versus output temperature T o at the same space velocities as in FIG. 3;
FIG. 5 are conversion curves X A versus output temperature T o at constant space time r but varying input temperatures T i superimposed on the equilibrium curve for the system;
FIG. 6 is a graph showing methanol conversion versus rate constant input temperatures T i
T.sub.1 =536.7° K., T.sub.2 =570.7° K. and T.sub.3 =581.3° K.;
FIG. 7 is a graph of stimulated behaviour of output temperature T o as a function of input temperature in an adiabatic reactor for methanol synthesis operating under the conditions of FIG. 1 at space velocities of FIG. 3;
FIG. 8 is a graph of methanol conversion versus temperature for the initial temperatures T 1 =536.7° K., T 2 =570.7° K., determined in FIG. 3; and FIG. 9 is a schematic diagram of a temperature scanning reactor used in the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 shows an equilibrium curve for methanol synthesis at 333 atmospheres, two constant rate curves, and an adiabatic operating line, on coordinates showing the fraction converted versus the reaction-system temperature. Curve (A) corresponds to a rate of 10 -8 kmol (kg cat) -1 h -1 and in essence represents the equilibrium for this system. Curve B corresponds to a rate of 2×10 -3 kmol (kg cat) -1 h -1 , and, curve C corresponds to a rate of to 5×10 -3 kmol (kg cat) -1 h -1 . The feed composition has CO:H 2 :N 2 :He:CO 2 in the ratio 1:5:1:2:1 at 333 atmospheres. The curves here and in the other figures were obtained using RESIM, an adiabatic reactor simulation program for the PC which uses the kinetics and parameters quoted by Capelli et al in "Mathematical Model for Simulating Behaviour of Fauser-Montecatini Industrial Reactors for Methanol Synthesis", I. & EC. Proc. Des. Dev. II(2), (1972) p. 184-190. These data were obtained using established kinetics. An adiabatic reactor whose feed enters at the temperature where the operating line crosses X A =0 will yield an output at steady state which will invariably fall on this operating line. Exactly how far up this line the output will fall depends on the space velocity used. In the ideal case, all features of FIG. 1 are fixed for each pressure, catalyst, and feed composition including changes in inerts.
The equation of the operating line in this simplest case is:
X.sub.A =C.sub.p T/-H.sub.r (1)
Thus, X A is directly proportional to T. This is true in systems which do not have significant secondary reactions or parallel reactions of different orders and do not lose heat to the reactor components or the surroundings. The matter becomes somewhat more complicated in the real world when the reactor and catalyst have finite heat capacities and heat loss may be unavoidable. In that case, the basic heat balance equation becomes:
heat input=heat output
+heat generated by reaction
+heat accumulated in the reactor
+heat lost to surroundings
Because a scanning reactor will be examined, which operates in a transient or nonsteady state mode, the accumulation term cannot be ignored. By convention, the input condition is the enthalpy datum: i.e. heat input=0.
The heat output term will depend on the composition of the products and can be written:
heat output=C.sub.p (T.sub.o -T.sub.i)(1-X.sub.A)+C.sub.pp1 (T.sub.o -T.sub.i)(X.sub.A -X.sub.p)(X.sub.A -X.sub.p)+C.sub.pp2 (T.sub.o -T.sub.i X.sub.p)
where only one primary product p1 and one secondary product p2 are postulated. More complex systems can be envisioned without changing the overall conclusions.
In accounting for heats of reaction, the heat of conversion of reactant to primary product p1 and the heat of conversion of that product to the secondary product p2 must be considered:
heat generation by reaction=H.sub.ri X.sub.A H.sub.pi X.sub.p
where X p is the fraction of conversion of the reactant A to secondary products p2 while X A is the total fraction of reactant A converted. The subscripts ri and pi refer to heats of reaction of the feed A to p1 and p2 at the inlet temperature T i .
In considering the accumulation terms, the heat capacity and mass of each of the components of the reactor must be considered. These will include walls, the catalyst charge and any other items present in the reactor: ##EQU1## where the term T S is the temperature difference between the reactor walls etc. and the reactants and the subscript s indicates the component of the reactor. The heat capacity C ps is expressed in units commensurate with those of m, the quantity of a solid component in the reactor. Since at the beginning of a temperature scan the reactor is all at T i , T s is a function of both time and position in the reactor.
Finally, heat losses from the reactor will take the form:
heat loss=Σh.sub.f S.sub.2 fT.sub.f
where h is the heat transfer coefficient, s is the heat transfer surface and T f is the driving force due to temperature difference between the reactor component f and its surroundings. Again, T f will be a function of time. These terms are collected to present a more complete form of equation 1 ##EQU2##
It can be seen that Equation 1a reduces to Equation 1 when all of the following are true:
a) secondary reaction does not occur and X p =0
b) the heat capacity of the reactor is very small and C ps →0 or when heat transfer to the reactor material is very slow, or at steady state when T S =0
c) heat loss from the reactor components is small because
1) h f are all very small
2) T f is minimized by appropriate instrument design.
Under appropriate conditions, there will exist a unique operating line for every real reactor under a prescribed set of operating conditions and, in the case of the adiabatic reactor, it is obvious that the operating line is unique. The reaction rate curves, on the other hand, are independent of the heat effects and will depend only on temperature, feed composition, catalyst activity and pressure regardless of adiabaticity.
To get from the input condition shown as T 1 in FIG. 1 to an output condition at B 1 using a plug flow reactor (PFR) will require a certain space time r B1 . To reach condition C 1 from T 1 will require a different space time rC 1 >rB 1 , etc. In a PFR, each point on the operating line is reached at a unique space time.
At the space velocity which results in rB 1 , an output conversion X AB1 will be achieved which will be changing at a rate corresponding to constant rate curve B, regardless of how this point is reached either along an ideal operating line given by equation 1 or along a more complicated path given by equation 1a or its elaborations. If space velocity is decreased, i.e. increase r to rC 1 , condition C 1 will be reached which is the maximum rate achievable on the operating line starting at T 1 and lies on constant rate curve C. Further increases in r will result in higher conversions but at decreasing rates. On the way to equilibrium conversion on Curve A, curve B will be encountered again at condition B 2 . The rate at B 1 and B 2 will be the same; at B 1 it will occur at low conversion and low temperature while at B 2 it will take place at high conversion and high temperature. It is clear therefore, that the reactor can be operating at B 1 or B 2 under non-steady state conditions, and it is apparent that the temperature profile along the length of the reactor, before the condition at B 1 or B 2 is reached, need not be the same as that which would result if input temperature was constant. It will be appreciated that, in contrast, a steady state condition is one which would eventually be reached at a sufficiently long time from the beginning of the observation if the input temperature, composition etc. is maintained at a constant value. If this constant value is changed, a finite amount of time must elapse before a new steady state is achieved. Nevertheless, at each instant during the transient the instantaneous rate of reaction of a system at point B 1 or B 2 is defined by the temperature and conversion alone. That condition is completely independent of the conditions along the reactor proceeding or succeeding that condition and hence is independent of whether the system as a whole is at steady state or not.
FIG. 2 shows a plot of the reciprocal rate versus conversion. From reactor design, theory, this information is used to size the reactor using the general equation: ##EQU3##
The area under the curve on FIG. 2 between X A =0 and X A =X Af is ##EQU4## Equation 3 is valid whether the temperature of the system is constant or not. At constant temperature T: ##EQU5## In order to obtain the rate at a given reaction temperature;, the value of dX A /dr at that temperature is required. This information is routinely obtained in isothermal reactors, however, in TS-PFRs, it may be most readily obtained, not by the procedure of incrementing the input space velocity, but by the simple procedure of ramping the input temperature at constant space velocity and composition, so as to scan an input temperature range from T min to T max and observing the conversion X A and temperature T o at the outlet of the reactor at each instant during the scan.
The temperature scanning procedure is equivalent to investigating the output condition, at constant r, on a succession of operating lines, as identified for the 2.1 WHSV curve on FIGS. 3 and 8 by points 3, 4, and 5. In FIG. 3 a series of curves showing how X A varies with the input temperature (T i ) as a result of scans for various constant values of r, all at constant composition and pressure are shown. In practise, the input temperature is ramped until a preset maximum output temperature T omax is recorded, to protect the reactor or the catalyst or simply to avoid reaching equilibrium conversion. After each scan, a data set consisting of triplets of readings of T i , T o and X A at corresponding times during the scan is collected.
Such a data set was used to produce FIG. 3 and can also be plotted in another form by plotting X A versus T o as shown in FIG. 4. There is little point in pushing the inlet temperature too high as can be seen by superimposing FIG. 4 on the rate curves of FIG. 1 as shown in FIG. 5. At input temperatures above a certain value, the equilibrium condition at the output, as indicated by the uppermost curve corresponding to WHSV=0.1 is obtained. To investigate the kinetics of a reaction it is preferable to stay below, in fact well away from equilibriums.
In FIG. 3, it can be seen that at any T i values of X A at as many values of r as have been investigated can be obtained. In fact, many sets of such values at various inlet temperatures T i , within the range of temperature studied can be obtained. Each such set can then be plotted as shown in FIG. 6. The curves on FIG. 6 are curves of conversion vs space time along operating lines starting at the various temperatures indicated. Differentiating the curves on FIG. 6 produces dX A /dr at constant T i and the information necessary to plot FIG. 2. These are the rates which might be observed along an operating line starting at a given T i if such a measurement were possible. The functional form of the operating line does not matter, as long as there exists a unique operating line for the conditions used.
From a family of curves such as those shown on FIG. 2, the constant rate curves shown on FIG. 1 can be constructed and hence all the information necessary for kinetic model fitting can be obtained. Experimental operating lines which can be used to evaluate the heat effects involved in the reaction can also be generated. For each X A and T i from FIG. 3, at T o can be read off, for the same r, on FIG. 4. These give a set of values of X A and T o at constant T i . This data, when plotted as X A vs T o , will produce an experimental operating line.
If the experimental operating lines are almost straight, it can be assumed that the reaction products either are stable or do not have a significant heat of reaction during conversion to secondary products and that the heat loss and accumulation terms in equation 1a are unimportant. If the primary products react to secondary products endothermally, the operating lines will be concave or tend to curl up. Large temperature effects in the heat capacities of products and reactants can also induce curvature in the operating lines. Other effects, such as heat transfer from the reactants to the catalyst or other materials in the reactor, will also induce a concave curvature of the operating lines in ways which in some cases can be quantified. Careful determination of reactor and catalyst heat capacities, of the heats of reaction for secondary reactions and minimization of heat loss in order to approach adiabatic conditions, can be used to derive a fuller description of the observed operating lines. The time-dependent terms of Equation 1a can also be evaluated by suitable instrument calibration procedures.
Even if nothing of the chemistry, thermodynamics or kinetics of the reaction is known, useful qualitative information about the reaction from data such as that shown in FIG. 3 can be obtained. A Temperature Scanning Reactor (TSR) run plotted on the coordinates of FIG. 3, when repeated on a different catalyst formulation, will show if the new catalyst is more active. The curves for the more active catalyst would lie above those for the less active. There is nothing to prevent two such curves, obtained on different catalysts, from crossing. This would simply indicate that the activation energies or mechanisms of reaction are different on the two catalysts, thereby providing additional useful information.
Experimental Procedure
An automated temperature scanning reactor 1 apparatus, as seen in FIG. 9, can be set up in such a way that feed space velocity is maintained at a constant value, while reactant input temperature T i at gas inlet 2 is ramped over a range of temperatures ending at some input temperature which results in a maximum allowed output temperature T omax at gas outlet 3. The reactor 1 is then cooled, equilibrated at its initial input temperature T imin and a new space velocity selected. The ramping of the temperature is repeated and stopped again when T omax is reached. The procedure is repeated at as many space velocities as necessary, say about 10. The data gathered during each temperature scan consist of a set of T i and corresponding T o . If necessary, X A is followed at the same time using on-line FTIR or MS analysis using a mass spectrometer 4 or other analytical facility for continuous monitoring of output conversion. In the best of cases, X A may be related to T by calculation or by auxiliary experiments.
An experimental setup which approaches an ideal adiabatic reactor is useful for simplifying the measurement of X A . In the ideal case, equation 1 will apply and X A can be calculated from the difference between T o and T i . Departures from the adiabatic condition may necessitate the evaluation of the correction terms in equation 1a. If the necessary terms can be quantified, an instantaneous conversion monitoring detector at the outlet of the reactor is unnecessary. Thus a series of temperature scans will yield for each space velocity a set of data consisting of the triplets T i , T o and X A .
The data logging, temperature scanning and space velocity changes can all be put under the control of a computer 5. The experimental data consisting of sets of T i and T o and X A at various will be logged numerically or presented graphically on recorder 6 to look like the curves shown in FIG. 3, 4 or 7. These are the raw data presentations.
Using X A data in the form shown in FIG. 4, one or more output temperatures, at which isothermal rate constants are required are selected. In this example T=640K is selected and it is found that the output conversions which occur at this temperature at the three space velocities of 0.1, 1.1 and 2.1 hr -1 are 0.39, 0.27 and 0.23. The corresponding conditions are labelled with circled 1, 2 and 3 for cross reference with other figures. These conversions are used in FIG. 3 to find the input temperatures T i which lead to these output conditions.
Now, the values for T i thus determined lie at X A =0 on the operating lines shown on FIG. 8 and X A values form the FIG. 4 should all occur at 640K on the appropriate operating lines, as they clearly do.
If enough scans at various values of r are made it is possible to draw curves such as those shown in FIG. 6 to an arbitrary degree of precision by plotting X A vs r at each T i . FIG. 6 is simply a new representation of the experimental data obtained by remapping the raw data. Differentiating the curves on FIG. 6 produces values for plotting FIG. 2. FIG. 2 is also derived from the experimental data and represents the rates of reaction along operating lines. Because it is necessary to differentiate the data on FIG. 6 to obtain FIG. 2, it is clear that enough runs with appropriate values of r to make the numerical differentiation accurate will be required.
All that remains is to read the rates from the appropriate curves on FIG. 2 or from a plot of X A vs rate for the X A values at the 640K selected on FIG. 4. This produces a set of rates and corresponding conversions at the selected reaction temperature T=640K. This isothermal rate data can be treated in a conventional fashion by fitting it to postulated kinetic models using graphical or statistical methods.
If the feed contains more than one component, this procedure should be repeated at a number of feed compositions in order to determine the kinetic effect of each component in the system. This can be automated and need not complicate data gathering or interpretation beyond what is described above.
Data Handling Formalism
All of the above can be readily programmed on a computer by applying the following transformations of the basic T i , T o and X A data set.
Let T i (i) be the set of input temperatures with i=1 to m
r(j) be the set of space times (or 1/WHSV) with j=1 to n
T o (i,j) be the set of output temperatures
X A (i,j) be the set of output conversions.
In practice the set of input and output temperatures will be dense, and linear interpolations between adjacent measured results in the i direction can be applied. The space velocity set will, for reasons of economy of effort, be much sparser and necessitate second order interpolations.
When the rate of reaction is considered, and if the data in the j direction are sparse, a quadratic interpolation might be used: ##EQU6## for all j=2, . . . , n-1 while for the end members of the set ##EQU7## In the above, C A0 is the initial feed concentration of the base component A whose conversion we are tracking. The formulas can be simplified somewhat by carrying out the experimental program so that for all j the step size in space time is the same:
r.sub.j -r.sub.j-1 =constant (10)
Alternately spline functions may be fitted and differentiated directly.
A complete table of rates r(i,j) can therefore be assembled in one-to-one correspondence with the measurements of T o and X A . This can then be used in a program which simultaneously evaluates all rate constants and their Arrhenius parameters.
If the density in the i direction is high, rates at any desired temperature can be interpolated within the range of the scan by linear interpolation and rate constants at selected isothermal conditions can be evaluated. In the linear case, an output temperature T o (k,j) such that k is constant for all j is selected. Output temperatures which bracket the desired T o at each r are identified. Let these output temperatures be:
lower value=T.sub.o (l,j)
higher value=T.sub.o (h,j)
where l and h correspond to actually measured values of T o at conditions l and h. Each of these conditions has a corresponding rate r(l,j) and r(h,j). These can be linearly interpolated to give the new rates at k enlarging the set of available temperature conditions to m+1: ##EQU8## The corresponding conversion is: ##EQU9## In this way, a set of r(k,j) and corresponding X A (k,j) values is calculated. Such sets of isothermal rates and corresponding conversions can be obtained at many temperatures. They can be processed further by well-known means to determine the best kinetic expression and its parameters using model discrimination techniques or, in cases when the rate expression is known, to produce rate parameters, activation energies, etc. As FIG. 6 makes plain, the important experimental requirement is that enough space velocities must be used to define the curves of X A versus r in sufficient detail so that equations 8-10, or other fitting procedures, are applicable within tolerable limits. The policy of keeping (r j -r j-1 ) constant, though it simplifies computation, may require a large number of experiments to determine each X A versus r curve with adequate precision. In general, it may be best to vary (r j -r j-1 ) in order to minimize experimental effort and define each curve in as much detail as is necessary.
If each value of r can be scanned in 30 minutes, and if 10 values of r will suffice for a given investigation, and if it takes 30 minutes to reset T i rain and change the space velocity, then a typical completely automated kinetic investigation using the TSAR should produce a best-fit model and its full set of kinetic parameters in something like a 24-hour period of automated data collection.
The data will yield, in principle, an unlimited number of isothermal data sets of r A and X A between the limits of the scans with something in the order of 10 space velocities at each temperature. This abundance of information, available in 24 hours, should be compared to the small set of data normally generated in months-long kinetic investigations.
It will be appreciated that while this invention has been described with reference to a plug flow reactor (PFR) and particularly an adiabatic plug flow reactor (APFR), the principles thereof are equally applicable to Continuous Stirred Tank Reactors (CSTR), Batch Reactors (BR), and Stream Swept Reactors (SSR).
The operating procedures for the CSTR are the same as for the Plug Flow Reactor i.e. ramping input temperature and recording output temperature and conversion. The equations required to calculate rates from CSTR data are simpler than those described above for the PFR and this alone may make the use of a suitable CSTR preferred in the application of the experimental methods described above. The CSTR has other attractive features such as better temperature control and lack of thermal gradients which may make its application even more attractive.
Also, since different runs of a CSTR do not, unlike the PFR, need to have identical temperature rampings, it is possible to adopt much more flexible temperature ramping schemes; this makes it much easier to obtain data in any desired region of the Conversion-Temperature (X-T) Plane. For instance, although linear ramping may be easier to automate, non-linear ramping may be preferable in some cases, and is equally satisfactory for data analysis purposes.
More elaborately, since during a CSTR run the operator may freely vary any or all of input temperature, reactor temperature, and feed space velocity, it may be advantageous to use current output conversion and temperature conditions while a run is in progress to allow the operator, either manually or with feedback software, to vary any of these parameters so as to drive the system into any desired region of the X-T Plane, or in fact to drive it along any desired curve in the X-T Plane.
In the case of Batch Reactors (BR) it is possible to maintain uniform temperature in the reactor while ramping the temperature over a selected range. The advantage of this type of reactor is that high pressure reactions or the reactions of solids may be investigated by ramping the temperature of reactor contents while observing the degree of conversion and the temperature of the contents. This operation is advantageous in cases where kinetics are at present being studied in batch autoclaves or in atmospheric pressure batch reactors.
As with the CSTR, different runs of a batch reactor do not need to have identical temperature rampings. It is possible therefore to similarly adopt much more flexible temperature ramping schemes, making it much easier to obtain data in any desired region of the Conversion--Temperature Plane. Two such schemes easily automated are:
(a) repeatedly ramping the temperature of the batch reactor rapidly over a selected ranges of temperatures, starting at the same low initial temperature and using different ramping rates; and;
(b) maintaining the external temperature of the batch reactor at a series of fixed temperatures while allowing the heat of reaction to drive the internal reactor temperature where it will.
More elaborately, one may also use feedback from current conditions to vary the temperature so as to drive the system as desired. It is noted however that fewer control parameters are available than with the CSTR, namely just the exterior temperature of the reactor.
It is also clear that it is not necessary to operate the reactor isothermally. Instead, the temperature is ramped, either by external heaters or by the heat of reaction itself; the exact form of the temperature ramping is not important. The temperature is recorded continuously (or at short time intervals). Also the concentration C A is measured continuously or at short time intervals (e.g., using a mass spectrometer or other suitable measuring device). dC A /dt can then be calculated at any time by numerical differentiation, and the rate r A calculated from the Equation r A =dC A /dt. This is the rate corresponding to the current temperature and conversion at that instant during the ramp.
From such a single run of the batch reactor, rates along some curve in the Conversion-Temperature (X-T) plane can be obtained. This may then be repeated for several runs of the batch reactor with different temperature control policies, to obtain several curves in the X-T plane. From this family of curves, isothermal rate data can be extracted by "reading across" the curves at some selected temperature. The usual data fitting for a proposed rate expression can then be performed to obtain isothermal rate constants at this selected temperature. In addition, since the same family of curves can be used to obtain isothermal rate constants for any temperature encountered during the runs, it would be easy to plot and examine the temperature dependence of these isothermal rate constants.
In the case of Stream Swept Reactors, consider an experiment with some material A in a reactor being swept by a fluid and either reacting, or adsorbing, or desorbing to produce some product B. Denote by N o the total amount of A present in the solid at the beginning of a run, and by N(t) the amount of A left at time t (in convenient units--moles, grams, etc). Consider the rate of reaction:
r.sub.A (t)=-(1/N.sub.o)(dN/dt) (2)
Supposing all of A eventually reacts or desorbs, so N(∞)=0, then: ##EQU10## Then Equation 2 becomes ##EQU11##
Now consider two cases:
(i) where the material in the reactor can be measured directly (e.g. by weighing), and
(ii) where the product B can be measured as it exits the reactor. In either of these cases it is easy to calculate reaction rates, as follows.
In case (i), let W be the amount of inert material in the reactor, and M(t) the total amount of reactive sample in the reactor, so:
M(t)=W+N(t). (5)
If M(t) is measured and recorded continuously then at the end of the run one may calculate:
N.sub.o =M(O)-M(∞), (6)
and
N(t)=M(t)-M(∞). (7)
If N(t) can be measured and recorded directly, then the above steps are unnecessary. In any case, N(t) or M(t) may be numerically differentiated to calculate dN/dt=dM/dt. From this, Equation 2 may be used to calculate r A .
In case (ii), let P(t) measure the rate at which the product B exits the reactor at time t. P(t) might for instance be the concentration of B in the exit stream. P(t) is proportional to dN/dt; the proportionality constant will depend on the stoichiometry of the reaction, on the rate of flow of the fluid through the reactor, and on the units of measurement used for A, B, and P(t), but there will be some constant p such that
dN/dt=-pP(t). (8)
Then from Equation 3: ##EQU12## and hence from Equation 4 it follows that: ##EQU13##
Note that neither case (i) nor case (ii) require any calibration of measuring instruments, or knowledge of the stoichiometry of the reaction, or even knowledge of the flow rate; any such factors cancel out in Equations 2 and 10, yielding quantitative rates from relative measurements.
The physical set-up for a Stream-Swept Reactor experiment is the same as for a Temperature-Programmed Desorption (TPD) experiment, and in both cases the temperature of the sweeping fluid and of the sample is ramped. However, in a TPD experiment the data is collected as N(T) vs T disregarding the time dimension. For a Stream-Swept Reactor experiment, on the other hand, it is essential to record the temperature (T) and conversion (N(t) as functions of time (t). The stream can be temperature-ramped in any convenient way; the specifics do not affect Equations 2 or 10. At any time t the fraction of A converted is (for case (i) and case (ii) respectively): ##EQU14##
Thus for each time t some temperature T, conversion X, and the corresponding rate rA given by Equation 2 or 10 is obtained. A single run thus produces rates along some curve in the X-T plane. As in the BR discussed above, several of these curves, for different ramping rates of the reactor, can be combined to yield sets of isothermal rates. Again as above, from this isothermal rate constants and their temperature dependence can be obtained.
The rate of data acquisition can be doubled over and above that available by means of the procedures described above by the simple expedient of ramping the temperature up to a selected limit at a fixed space velocity and, instead of cooling back to the initial condition before the next data acquisition run, proceeding to change the space velocity at the high temperature limit and cooling the reactor with feed being supplied at the new space velocity. Data can then be acquired both on the temperature up-ramp and on the down-ramp. The space velocity is once again changed at the bottom of the ramp and a new up-ramp initiated. In this procedure there is essentially no "idle time" for the reactor and productivity of the apparatus is maximized.
Note also that the methods outlined in the above are applicable with minor alterations to cases where the reactor is not operated in an adiabatic manner, cases where the volume of the reacting mixture changes due to conversion and a number of other complications which are known to occur in such systems.
There are also two special conditions which apply to PFRs and BRs, wherein heat transfer is either very slow or very fast.
(i) If heat transfer is very slow, then in the limit, when heat transfer rates are zero, an adiabatic reactor is achieved. Conversion is then proportional to temperature change ΔT along (or in) the reactor, and the operating lines are normally found to be straight.
(ii) If heat transfer is very rapid through the reactor wall and/or into the catalyst, then at each moment during the run the reactor (PFR or BR) is operating isothermally at the temperature of the surroundings, and throughout the run in the PFR, exit temperature is equal to inlet temperature. For a PFR this also implies that throughout a run exit temperature is equal to inlet temperature. Consequently, although in the TSR technique data from PFR runs is ordinarily used to plot outlet conversion X vs r for a given inlet temperature (as described previously), in this special case we may equivalently pick some outlet (=inlet) temperature T and plot X vs r gathered from different runs at the selected T. This simplified procedure uses the same TSR data according to the methods described hereinabove. The slope of this new X vs r curve gives the isothermal rates r A (X,T) for this temperature directly.
These two extreme cases, adiabatic and isothermal, are the cases traditionally used. With the TSR technique and the recognition that thermal equilibrium is not necessary, all the middle ground between these extremes is available for use. In particular, although it may be desirable for various reasons to approximate adiabatic or isothermal conditions, it is not necessary to achieve them exactly for meaningful results to be obtained.
It will be appreciated that the above procedure only works when the condition of T in =T out applies. Incorrect rates will be obtained in all cases except the special case where the reactor is operating isothermally over the reactor length at each instant during the ramping procedure.
Adiabatic operation with a constant input temperature has, heretofore rarely been used as it is difficult to build a perfectly adiabatic reactor. The concept of scanning the input temperature of such a reactor is the subject matter of our earlier filed application. | A method for rapidly collecting kinetic rate data from a temperature scanning reactor for chemical reactions. The method, which is particularly useful for studying catalytic reactions, involves ramping (scanning) of the input temperature to a reactor and recording of output conversion and bed temperature without waiting for isothermal steady state to be established. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention generally relates to shared memory buffer management in network nodes. More specifically, the invention relates to the use of dynamic spare buffering for multi-class network traffic.
[0003] 2. Background Art
[0004] Data networks are used to transmit information between two or more endpoints connected to the network. The data is transmitted in packets, with each packet containing a header describing, among other things, the source and destination of the data packet, and a body containing the actual data. The data can represent various forms of information, such as text, graphics, audio, or video.
[0005] Data networks are generally made up of multiple network nodes connected by links. The data packets travel between endpoints by traversing the various nodes and links of the network. Thus, when a data packet enters a network node, the destination information in the header of the packet instructs the node as to the next destination for that data packet. A single data packet may traverse many network nodes prior to reaching its final destination.
[0006] Each network node may have multiple input ports and output ports. As a data packet is received at a network node, it is transmitted to its next destination in the network via an appropriate output port of the node. Depending on the amount and nature of the data packets entering a network node, it is possible that the node will not be able to output the data packets at a rate sufficient to keep up with the rate that the data packets are received. In the simplest design of a network node, newly arriving data packets may simply be discarded if the output rate of the node cannot keep up with the rate of receipt of new packets.
[0007] More advanced network nodes have a buffer stored in a memory of the network node such that data packets may be held in a queue prior to being output from the node. In such a configuration, if data packets are received at a rate faster than the node is able to output the data packets, the newly received data packets are queued in a memory buffer of the node until such time as they may be transmitted. However, since the buffer is of a finite size, it is still possible that the rate of receipt will be such that the buffer will become full. One solution is to drop any new incoming data packets when the buffer is full. However, one problem with this solution is that it may be desirable to give different types of data packets different priorities. For example, if data packets are carrying a residential telephone call, it may be acceptable to drop a data packet periodically because the degradation in service may not be noticeable by the people engaging in the conversation. However, if the data packets are carrying data for a high-speed computer application, the loss of even one data packet may corrupt the data resulting in a severe problem.
[0008] As a result of the need to differentiate the types of data packets, different data packets may be associated with different traffic classes. A traffic class is a description of the type of service the data packets are providing, and each traffic class may be associated with a different loss priority. For example, a traffic class of “residential telephone” may have a relatively low loss priority as compared with a traffic class of “high speed data”.
[0009] Buffer management due to traffic congestion is an important aspect of networking and communication systems such as routers and switches. The first line of defense against congestions is to have sufficiently large buffering available. Sufficiently large buffering is necessary to minimize packet loss and to maximize the utilization of the network links. However, switches/routers have fixed amount of memory (DRAM) and therefore their buffers have limited size. As the link capacity increases, for example from 1 Gbit/sec to 10 Gbit/sec, effective buffer management becomes even more imperative as significantly large buffers will have a major cost increase on the system. The cost impact of large buffers is even more significant when the system has to support multiple traffic classes for diversified user traffic in order to provide different classes of QoS (Quality of Service). In such systems, packets are assigned into various queue classes based on their application types. However, due to the unpredictability nature of traffic patterns, it is not feasible to accurately size each queue class. Therefore in time of congestion, some queues overflow and as a result packet loss occurs. A typical approach to minimize packet loss is to use sufficiently large queues (i.e., large memory) to minimize packet loss.
SUMMARY OF THE INVENTION
[0010] An object of this invention is to improve buffering methods for multi-class network traffic.
[0011] Another object of the invention is to provide a dynamic spare buffering method for support of multi-class traffic, which avoids requiring large queues in the presence of unpredictable traffic patterns.
[0012] These and other objectives are attained with a method of and system for allocating a buffer. The method comprises the steps of partitioning less than the total buffer storage capacity to a plurality of queue classes, allocating the remaining buffer storage as a spare buffer, and assigning incoming packets into said queue classes based on the packet type. When a queue becomes congested, incoming packets are tagged with the assigned queue class and these additional incoming packets are sent to said spare buffer. When the congested queue class has space available, the additional incoming packets in said spare buffer are pushed into the tail of the congested queue class.
[0013] Further benefits and advantages of the invention will become apparent from a consideration of the following detailed description, given with reference to the accompanying drawings which specify and show preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a block diagram of a network node with which the present invention may be used.
[0015] FIG. 2 is a more detailed diagram illustrating the preferred buffering method of this invention.
[0016] FIG. 3 is a flow chart showing the packet arrival operation in accordance with the preferred embodiment of this invention.
[0017] FIG. 4 is a flow chart illustrating the packet departure operation of the preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] FIG. 1 shows a block diagram of a network node 100 in which the present invention may be utilized. Network node 100 includes input ports 102 for receiving data packets from input links 104 . Network node 100 also includes output ports 106 for transmitting data packets on output links 108 . Switching module 110 is connected to input ports 102 and output ports 106 for switching data packets received on any input link 104 to any output link 108 . A processor 112 is connected to a memory unit 114 , input ports 102 , switching module 110 , and output ports 106 . The processor controls the overall functioning of the network node 100 by executing computer program instructions stored in memory 114 . Although memory 114 is shown in FIG. 1 as a single element, memory 114 maybe made up of several memory units. Further, memory 114 may be made up of different types of memory, such as random access memory (RAM), read-only memory (ROM), magnetic disk storage, optical disk storage, or any other type of computer storage. One skilled in the art will recognize that FIG. 1 is a high level functional diagram of a network node configured to operate in accordance with the present invention. An actual network node would have additional elements in order to perform all the functions of a network node, however such additional elements are not shown in FIG. 1 for clarity.
[0019] In operation, as data packets are received at input ports 102 via input links 104 , processor 112 will determine the appropriate output link 108 on which to output the data packet, and the processor will control switch module 110 in an appropriate manner so that the data packet is sent out on the appropriate output port 106 and output link 108 . However, data packets may arrive at network node 100 at a rate, which is faster than the network node 100 can output the data packets. Therefore, at least a portion of memory 114 is configured as a buffer, so that received data packets may be stored in the buffer until ready to be output. However, it is possible that the rate of receipt of data packets will be high enough such that the buffer will fill up. In such a case, some data packets will be lost. The present invention provides a technique for managing a data packet buffer in a network node 100 for efficient use of allocated buffer memory.
[0020] FIG. 2 generally illustrates a preferred buffering method of the present invention. As in typical systems, the system memory (i.e., buffer 200 ) is partitioned into various queue classes for supporting different traffic types. As an example, three queue classes 202 , 204 , 206 are shown. In accordance with the present invention, a spare buffer 210 is also defined and is allocated some amount of memory. The system memory can be partitioned between the various queue classes and the spare buffer in different ways. For example, in one approach, the system memory can be divided up between the queues and the spare buffer in equal amount. In another approach, the system memory can be divided up between the queues based on the amount traffic expected for each traffic class with some portion set aside for the spare buffer.
[0021] The way this method with the spare buffer works is as follows. As packets 212 arrive they are assigned into various queue classes based on their type (or application type) and the queues are serviced by a scheduler 214 according to a scheduling scheme. For example, each queue can be assigned a relative weight (e.g., 35% real-time queue [class-1], 15% interactive queue [class-2], and 50% network control traffic queue [class-3]). The scheduler can then service queues in a round-robin fashion in proportion to the weights assigned to the queues.
[0022] In the normal mode of operation when no queue class is congested, the spare buffer 210 is empty. However, if a queue class gets congested, then the overflow packets, represented at 216 , are tagged with their associated class and are assigned to the spare buffer. In a sense these overflow packets are linked with the tail of the congested queue. This is like increasing the size of a congested queue dynamically in real-time by the amount of the overflow packets. As packets in a congested queue class get serviced and space becomes available in the queue, the spare buffer 210 pushes the overflow packets out into the tail of the congested queue.
[0023] In the case that the spare buffer is full and overflow packets are still arriving, the arriving overflow packets are discarded.
[0024] FIGS. 3 and 4 show in more detail the preferred buffer allocation procedure of the instant invention.
[0025] In particular, FIG. 3 illustrates a preferred operation, generally referenced at 300 , when a data packet arrives. At step 302 , a check is made to determine if a new packet has arrived. If not, the procedure loops back to repeat this step. If a packet has arrived, the procedure goes to step 304 , where the routine determines the queue class in which the packet belongs. This determination can be made based on the packet type, for example, from the information coded in the packet header.
[0026] At step 306 , the operation determines whether that queue class, to which the packet belongs, is congested (i.e., full). If that queue class is not congested, the packet is put in the queue class at step 310 , and the routine returns to step 302 . If the associated queue class is congested, the routine proceeds to step 312 , where the routine determines if the spare buffer is full. If this spare buffer is not full, then at steps 314 and 316 , the overflow packet is tagged with the associated queue class and put in the spare buffer, and the routine returns to step 302 . However, if the spare buffer is full, the overflow packet is discarded at step 320 , and the routine then returns to step 302 .
[0027] FIG. 4 shows a preferred packet departure operation, generally referenced at 400 . In this operation, at step 402 , a check is made to determine if a packet has departed (i.e., the scheduler has serviced a packet from a queue class). If there has been no departure, the routine loops back to repeat this step. If a packet has departed, the routine moves on to step 404 , where a check is made to determine if the spare buffer is empty.
[0028] If the spare buffer is empty, the routine returns to step 402 . If the spare buffer is not empty, then at step 406 , the routine checks to determine if the spare buffer contains a tagged packet indicating the same class as the departed packet. If there is no such packet, the routine returns to step 402 . However, if there is such a tagged packet, then at step 410 that packet is pushed out from the spare buffer into the tail of the queue class from which the packet departed. (Note that the spare buffer operates in a FIFO manner for each packet class in order to preserve packet order for packets belonging to the same class. A selector logic, represented at 230 in FIG. 2 , pushes the packet into the tail of the corresponding queue class.)
[0029] The packet arrival and departure operations are parallel processes, which are executed independently.
[0030] As will be readily apparent to those skilled in the art, the present invention can be realized in hardware, software, or a combination of hardware and software. Any kind of computer/server system(s)—or other apparatus adapted for carrying out the methods described herein—is suited. A typical combination of hardware and software could be a general-purpose computer system with a computer program that, when loaded and executed, carries out the respective methods described herein. Alternatively, a specific use computer, containing specialized hardware for carrying out one or more of the functional tasks of the invention, could be utilized.
[0031] The present invention, or aspects thereof, can also be embodied in a computer program product, which comprises all the respective features enabling the implementation of the methods described herein, and which—when loaded in a computer system—is able to carry out these methods. Computer program, software program, program, or software, in the present context mean any expression, in any language, code or notation, of a set of instructions intended to cause a system having an information processing capability to perform a particular function either directly or after either or both of the following: (a) conversion to another language, code or notation; and/or (b) reproduction in a different material form.
[0032] While it is apparent that the invention herein disclosed is well calculated to fulfill the objects stated above, it will be appreciated that numerous modifications and embodiments may be devised by those skilled in the art, and it is intended that the appended claims cover all such modifications and embodiments as fall within the true spirit and scope of the present invention. | Disclosed are a method of and system for allocating a buffer. The method comprises the steps of partitioning less than the total buffer storage capacity to a plurality of queue classes, allocating the remaining buffer storage as a spare buffer, and assigning incoming packets into said queue classes based on the packet type. When a queue becomes congested, incoming packets are tagged with the assigned queue class and these additional incoming packets are sent to said spare buffer. When the congested queue class has space available, the additional incoming packets in said spare buffer are pushed into the tail of the congested queue class. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates generally to automatic control systems of the on/off mode type and more specifically to improvements in on/off mode control systems for better regulation about the system set point.
A fixed-bed coal gasifier is used to produce low BTU gas from the partial combustion of granular coal. Coal is introduced into the reaction chamber above the reaction zone and must be maintained at a prescribed level above the zone to maintain the desired product gas quality.
A coal feeder of the pocket type is used to feed coal into a fixed-bed coal gasifier. The coal feeder is of the conventional rotating pocket type. The speed control of the pocket rotors of the feeder is by means of a variable sheave drive. The sheave effective diameter is changed to vary the speed ratio from a constant speed electric motor prime mover. The sheave diameter is varied by means of a positioner that is electric motor driven in an on/off control mode. By running the positioner motor in forward or reverse directions, the feeder speed is increased or decreased. When the positioner motor is stopped, the feeder speed is maintained. One problem associated with the variable speed drive for automatic control is that it can not withstand the frequent speed jogging that it would be subjected to when used in a conventional automatic control system. Frequent jogging would quickly wear out the drive system and electrical control contacts.
Another problem is that the characteristics of this type of system which uses on/off mode control is that it will not allow large integral action to be used in controlling about a set point due to the lag introduced by the inherent system deadband. In the described system, the 90° phase lag of the feeder/bed integrating response function causes control loop cycling (oscillation) when even a small amount of integral action is used.
Further, the disclosed system introduces an additional control problem due to the actuation of the gasifier stirrer approximately every 15 minutes, which corresponds to the stirrer vertical travel cycle time. This produces about a 20 percent variation in the nuclear level detector's output caused by shadowing from the stirrer and the shaft coupling the drive to the stirrer. Because of this large unavoidable cyclical variation, only a limited proportional action (gain<1) can be used without undue jogging of the feeder speed drive. A gain less than one without accompanying integral action causes a considerable offset (steady state difference between set point bed level and achieved bed level) that could normally be eliminated by adding integral action. How fast the offset is removed when integral action is used depends upon the integral rate in repeats/minute set in the controller. Also, the controller must have adequate combined proportional/integral action to react to load perturbations and upsets such that large changes will not occur in the controlled bed level. A combination of gain=0.5 and an integral rate of 0.05 repeats/minute is barely adequate but still cycles as will be shown hereinbelow. If integral action is reduced to eliminate cycling, then too little control action results or if proportional action is increased, excessive jogging of the feeder speed control occurs.
Thus, there is a need for improvements in control systems for on/off mode controllers to provide improved regulation and prevent cycling of the control loop.
SUMMARY OF THE INVENTION
In view of the above need, it is an object of this invention to provide an improved control system for use with an on/off mode controller which substantially reduces control system cycling.
Other objects, advantages, and novel features of the invention will be set forth, in part, in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
To achieve the foregoing and other objects and in accordance with the purpose of the present invention, as embodied and broadly described herein, the device on/off mode control of a system operating parameter of this invention may comprise means for detecting the deviation of the system operating level by comparison with a set first level in a primary controller. The error signal from the primary controller is compared with the system parameter feed rate within a preselected deadband in a secondary controller which adjusts the feed rate in an on/off control mode to reduce the error signal. A modulating means is provided to modulate the error signal from the primary controller at a selected amplitude and frequency to substantially reduce cycling of the control system.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a bed level control system for a coal gasifier employing the on/off mode control system according to the present invention.
FIG. 2 is a schematic diagram of the secondary controller shown in block form in FIG. 1.
FIG. 3 is a plot comparing the fluctuation of coal feeder speed and bed level with and without the use of modulation of the primary controller error signal.
DETAILED DESCRIPTION
Referring now to FIG. 1 there is shown an on/off control system according to the present invention for use in controlling the coal bed level 5 of a coal gasifier 7. The gasifier 7 is of conventional design wherein air to support combustion is introduced through a bottom inlet 9. A grate 11 supports the bed above the air inlet. The bed includes an ash zone 13 immediately above the grate, a combustion zone 15 and a layer of coal 17 above the combustion zone which must be maintained at a preselected design level by varying the coal feed from a variable speed coal feeder 19 through a supply conduit 21. The product gas is taken off through a gas exit conduit 23.
The bed is continuously agitated by means of a stirrer 25 attached to a stirrer post 27. A stirrer drive mechanism 29 engages the post 27 at the top of the gasifier to both rotate and reciprocate the stirrer 25. The stirrer travels from just above the grate 11 to a point normally above the combustion zone 15 with a travel cycle of about 15 minutes.
As pointed out above, it is necessary to maintain the bed level constant for efficient operation. To accomplish this control in accordance with the present invention a conventional nuclear level gauge including a cobalt-60 radiation source 31 positioned on one side of the gasifier and a radiation detector 33 mounted on the opposite side of the gasifier is used to monitor the coal bed level. The gauge detects the degree of attenuation of the radiation by the bed. The detector is connected to produce a 1-5 volt output signal swing which is proportional to the bed level within the control range. The output of the detector is connected to the input of a proportional/integral controller 35, such as the Beckman Corp. model #8800, Fullerton, Calif. The detector 33 is mounted so that the output signal swing is centered about the desired bed level. In the example here the 1-5 volt swing corresponds to a bed level change between 74 and 84 inches elevation above the grate 11 with a control set point of 79 inches.
The controller 35 includes a means for adjusting the set point voltage for comparison with the input signal from the detector 33. The set point voltage in this example is 3.0 volts which corresponds to the 79 inch bed level. The controller is operated to provide a selected amount of proportional and integral action to reduce the undesirable control system cycling, as will be explained hereinbelow. The output signal from the controller 35 is an error signal in the form of a current signal which varies between 4-20 milliamps. This output error signal is fed to an output resistor 37 connected between the output of the primary controller 35 and ground potential. The resistor 37 is a 250-ohm resistor which produces an error signal voltage across it of 1-5 volts. This error signal varies inversely with the bed level in the selected control range.
The error signal voltage is connected to one input of a secondary controller 39 which is a specially designed controller having at least one deadband which compares the error signal voltage from the primary controller with a signal proportional to the speed of the coal feeder 19 from a tachometer 41. The tachometer is attached to detect the rotating speed of the coal feeder which is proportional to the rate of coal delivery to the gasifier. When the error signal deviates from the speed signal from the tachometer, which is selected to vary between 1-5 volts for the control range in this application, by more than half the deadband a comparator circuit within the secondary controller will close a contact to turn a coal feeder speed adjustor 43 "on" to either increase or decrease the coal feeder speed to raise or lower, respectively, the bed level within the gasifier.
The feeder speed adjustor 43 in this application is a positioner which is driven by a reversible electric motor to adjust the sheave diameter of a variable sheave drive mechanism of the coal feeder. The positioner motor will run in the direction it is switched on by the controller 39 until the comparator output signal is back within the deadband of the controller. The speed adjustor motor is then turned "off" and the adjusted coal feeder speed is maintained until the deviation swings out to the deadband limits again. Thus, as the output from the primary controller 35 changes due to an error in bed level, the control system changes the coal feeder speed and subsequently the coal feed rate to drive the measured bed level toward the set point level and to more closely match coal consumption rate in the gasifier bed. The coal consumption rate will vary with gas demand. In addition, the bed level is also upset by ash removal and by bed settling/lifting resulting from the stirrer 25 helical motion.
Referring now to FIG. 2 the secondary controller 39 will be described in detail. The circuit includes comparators 45 and 47 which control the raising and lowering, respectively, of the coal feeder speed. The comparator 45 is connected through a diode 49 and a load resistor 51 to ground potential. A positive voltage developed across the load resistor 51 when the output of the comparator goes positive is applied to the base of a transistor switch 53 turning it "on" and thereby activating a relay R1 coil to close the relay contacts 55. The contacts 55 are connected to the reversible motor controller of feeder speed adjustor 43 to run the motor in the forward direction so as to increase the coal feed rate.
Similarly, when the comparator 47 output goes positive the signal is applied through a diode 57, resistor 59 and transistor switch 61 to activate a relay R2 thereby closing the contacts 63 to run the speed adjustor motor in the reverse direction to lower the coal feed rate.
The non-inverting (+) input of comparator 45 is connected through a resistor 65 to receive the error voltage signal across resistor 37 at the output of the primary controller 35 (FIG. 1). This voltage signal is the set point, or reference, voltage (V sp ) for the secondary controller and is further applied through a resistor 67 to the inverting input (-) of comparator 47. The tachometer output voltage (V in ) is applied to the - input of comparator 45 through a resistor 69 and to the + input of comparator 47 through a resistor 71. The comparators 45 and 47 are connected in a positive feedback arrangement by connecting their outputs through resistors 73 and 75, respectively, to the + inputs. The comparators 45 and 47 are biased at their respective reference terminals by means of constant current circuit elements 77 and 79 connected in series with the input resistors 65 and 67. This voltage divider connection provides a positive bias on the (-) reference terminal of comparator 47 and a negative bias on the (+) reference terminal of comparator 45. This bias combined with the action of the positive feedback provides a triple deadband control arrangement wihch is centered about the V sp input voltage. For example, the voltage at the + terminal of comparator 45 is V sp minus the voltage drop across resistor 65 and the negative voltage feedback which is controlled by the ratio of the input resistance 65 to the feedback resistance 73. Therefore, as long as V in is greater than the voltage at the + input of comparator 45, the output of comparator 45 is negative and the relay contacts 55 remain open. When the bed level decreases to a point that V sp causes the + terminal of comparator 45 to become more positive than V in , the - terminal voltage, the output of comparator 45 goes positive, activating relay R1 to close contacts 55 and raise the coal feeder speed. The feeder speed will increase until V in becomes more positive than the voltage at the + terminal of comparator 45. Due to the voltage hysteresis introduced by the positive feedback, V in must increase to a value greater than the voltage differential required to trip the comparator. Due to the slow integral action of the primary controller, V sp will remain essentially constant during the feeder speed adjustment. This action provides a 2nd deadband within the primary deadband so that the feeder speed is increased to a point well within the primary deadband limits.
Similarly, the comparator 47 is biased to control the speed lowering deadband limit by the fact that the voltage differential across comparator 47 is V sp plus the drop across resistor 67 and the positive feedback voltage applied to the + terminal of comparator 47. Thus, when V sp goes down to an increase of the bed level, it must go below V in by an amount greater than the bias placed across the comparator inputs before the - terminal of comparator 47 becomes less positive than the + terminal of comparator 47, to switch the output of comparator 47 positive and lower the feeder speed. Due to the positive feedback voltage hysteresis, V in must fall below the voltage differential required to trip the comparator 47, thereby creating a 3rd deadband within the primary deadband's upper voltage limit. Thus, it will be seen that the secondary triple deadband controller adjusts the feeder speed to hold it within the primary deadband limits.
It will be appreciated by those skilled in the art that the system may be operated with only the primary deadband for systems which do not require the additional control made available by the 2nd and 3rd deadbands. This is accomplished by eliminating the positive feedback resistors in the comparator circuits.
To prevent oscillations in the above-described system, the error signal (V sp ) from the primary controller 35 is modulated by means of a triangular wave modulator 81. The modulator signal is a current wave which flows through the load resistor 37. The current is about 3.2 milliamps peak-to-peak across the 250 ohm load resistor 37. This voltage signal is centered about the error signal V sp by utilizing bipolar symmetrical triangular current modulation having a zero average value.
The proportional and integral action of the primary controller 35 is adjusted to obtain the best control of the system. However, the system continues to oscillate as shown in the righthand portion of FIG. 3. In the illustrated system, a combination of gain of 0.5 and an integral rate of 0.05 repeats/minute was found to provide the best control without the addition of the error signal modulation. Various modulation frequencies and amplitudes were examined from 0.0001 to 0.002 Hz and 0.5 to 1.0 volt peak-to-peak to optimize the response. The optimum modulation frequency was found to be about 0.0004 Hz with an amplitude of about 0.8 volt peak-to-peak. The result is shown in the lefthand portion of the plot of FIG. 3. The excessive cycling of the bed level and coal feeder speed is substantially elminated without excessive jogging of the coal feeder speed.
Thus, it will be appreciated that a control device for an on/off control system has been provided which improves regulation of a system variable operating parameter.
Although the invention has been illustrated for improvement in the control of bed level in a coal gasifier, it is also useful in almost any application for automatic control that uses on/off mode such as in electrical ovens, etc. It can provide much closer control without the large deviations caused by built-in deadbands (as in electrical heater oven controls to reduce wear and tear on contacts) and eliminate cycling (oscillation) occurring as a result of attempts by increasing integral (reset) action to obtain adequate control of a capacitive type process. For example, (1) the gasifier acts as a storage for mass (coal) or (2) an oven refractory/heated charge stores thermal energy similar to the way a capacitor stores electrical charge. A further specific application would be for household and industrial heating systems for better temperature regulation and in some cases improved energy efficiency. The frequency of the modulation signal for a particular system to be controlled would be selected at about six times the frequency of oscillation (cycling frequency) and the amplitude would be about 80% of the primary deadband.
The foregoing description of a preferred embodiment of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiment was chosen and described in order to best explain the principles of the invention as its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto. | A modulated control system is provided for improving regulation of the bed level in a fixed-bed coal gasifier into which coal is fed from a rotary coal feeder. A nuclear bed level gauge using a cobalt source and an ion chamber detector is used to detect the coal bed level in the gasifier. The detector signal is compared to a bed level set point signal in a primary controller which operates in proportional/integral modes to produce an error signal. The error signal is modulated by the injection of a triangular wave signal of a frequency of about 0.0004 Hz and an amplitude of about 80% of the primary deadband. The modulated error signal is fed to a triple-deadband secondary controller which jogs the coal feeder speed up or down by on/off control of a feeder speed change driver such that the gasifier bed level is driven toward the set point while preventing excessive cycling (oscillation) common in on/off mode automatic controllers of this type. Regulation of the bed level is achieved without excessive feeder speed control jogging. | 2 |
FIELD OF THE INVENTION
The present invention relates to mounting electronic surface mount devices to a mounting structure, and more specifically relates to a solder or conductive epoxy including filler to be used to mount surface mount devices to a mounting structure.
BACKGROUND OF THE INVENTION
Typically, the process of mounting a surface mount device to a mounting structure includes placing a conductive attach material such as solder or conductive epoxy on electronic contact pads of the structure, aligning electronic contact pads of the surface mount device with the contact pads of the structure, and placing the contact pads of the surface mount device onto the attach material. Due to the placement of the surface mount device and the force of gravity, the distance between the surface mount device and the structure is difficult to control. Often, the contact pads of the surface mount device come to rest on the contact pads of the structure, which may force the attach material to disperse and possibly short the contact pads of the surface mount device. Further, any subsequent heating of the surface mount device may allow reflow of the attach material, which may also short the contact pads of the surface mount device. In addition, the unpredictable distance between the surface mount device and the mounting structure is undesirable in some radio frequency applications, as the distance may affect circuit performance.
FIG. 1 illustrates a surface mount device 10 mounted to a mounting structure 12 as commonly known in the art. Electrical contact pads 14 and 16 of the surface mount device 10 and the mounting structure 12 , respectively, are connected by attach material 18 . By electrically attaching the contact pads 14 of the surface mount device 10 to the contact pads 16 of the mounting structure 12 , the surface mount device 10 is effectively mounted to the mounting structure 12 . For exemplary purposes, the attach material 18 is solder. The solder 18 is heated such that it is in a molten state when mounting the surface mount device 10 to the mounting structure 12 . The contact pads 14 of the surface mount device 10 are then aligned with the contact pads 16 of the mounting structure 12 , and the surface mount device 10 is placed on the solder 18 , thereby mounting the surface mount device 10 to the mounting structure 12 .
Due to the molten state of the solder 18 and the placing of the surface mount device 10 , a distance d between the surface mount device 10 and the mounting structure 12 is very difficult to control. In some cases, the distance d becomes extremely small and may approach zero. Therefore, the solder 18 may be compressed such that the contact pads 14 of the surface mount device 10 are shorted.
Once the surface mount device 10 is mounted to the mounting structure 12 , the mounting structure 12 may be mounted to a second mounting structure 20 . Contact pads 22 and 24 of the mounting structure 12 and the second mounting structure 20 , respectively, are aligned and electrically connected by attach material 26 . In order to mount the mounting structure 12 to the second mounting structure 20 , the attach material 26 is heated. In the case that the attach material 26 is solder, the attach material 26 is heated into its molten state during attachment. If the attach material 26 is conductive epoxy, the attach material 26 is heated in order to cure the attach material 26 . In either case, the heating of the attach material 26 may reheat the solder 18 connecting the surface mount device 10 to the mounting structure 12 . When reheated, the solder 18 may reflow and short the contact pads 14 of the surface mount device or other conductive areas
Similarly to the distance d, a second distance (not shown) between the mounting structure 12 and the second mounting structure 20 is difficult to control. Therefore, the placement of the mounting structure 12 onto the second mounting structure 20 or the force of gravity may cause the attach material 26 to short the contact pads of the mounting structure 12 .
The above discussion focuses on using solder as the attach material 18 ; however, problems similar to those associated with solder exist for other attach materials such as conductive epoxy. Thus, there remains a need for a cost-effective method for controlling the distance d between a surface mount device 10 and a mounting structure 12 and/or between two mounting structures 12 and 20 .
SUMMARY OF THE INVENTION
The present invention relates to electrically attaching a surface mount device to a mounting structure via their respective contact pads using an attach material, such as solder or conductive epoxy, which includes a filler material. In general, the filler material is relatively solid and granular shaped, wherein the diameter of the filler material controls a mounting distance between the surface mount device and the mounting structure. The filler allows the desired distance to be maintained during initial placement of the device and any subsequent reheating. The process of mounting the surface mount device to the mounting structure is achieved by placing the attach material including the filler material on the contact pads of the surface mount device and/or the contact pads of the mounting structure. The contact pads of the surface mount device are aligned with the contact pads of the mounting structure, and the surface mount device is placed onto the mounting structure. As the surface mount device settles into the attach material, the movement of the surface mount device towards the mounting structure is limited by the filler material. Once settled, the distance between the surface mount device and the mounting structure is defined by the diameter of the filler material.
Those skilled in the art will appreciate the scope of the present invention and realize additional aspects thereof after reading the following detailed description of the preferred embodiments in association with the accompanying drawing figures.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
The accompanying drawing figures incorporated in and forming a part of this specification illustrate several aspects of the invention, and together with the description serve to explain the principles of the invention.
FIG. 1 illustrates the mounting of a surface mount device to a mounting structure using solder as is commonly known in the art;
FIG. 2 illustrates mounting a surface mount electronic device to a structure using an attach material with filler according to one embodiment of the present invention;
FIG. 3 illustrates a surface mount electronic device mounted to a structure with attach material having filler according to one embodiment of the present invention; and
FIG. 4 illustrates a surface mount electronic device mounted to a structure using an attach material with filler wherein the area between the surface mount electronic device and the structure is filled with an underfill material according to one embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The embodiments set forth below represent the necessary information to enable those skilled in the art to practice the invention and illustrate the best mode of practicing the invention. Upon reading the following description in light of the accompanying drawing figures, those skilled in the art will understand the concepts of the invention and will recognize applications of these concepts not particularly addressed herein. It should be understood that these concepts and applications fall within the scope of the disclosure and the accompanying claims.
FIG. 2 illustrates an electronic surface mount device (SMD) 10 prior to mounting to a mounting structure 12 . For simplicity, only contact pads 14 and 16 of the surface mount device 10 and the structure 12 , respectively, are illustrated. However, the surface mount device 10 and the mounting structure 12 may have any number of contact pads. Further, the contact pads 14 and 16 are conductive and have a melting point greater than temperatures reached during the mounting of the surface mount device 10 to the mounting structure 12 . In addition, the surface mount device 10 may be any semiconductor device or passive component. The mounting structure 12 may be any structure to which it is desirable to mount the surface mount device 12 such as but not limited to a circuit board, a leadframe, or another electronic device.
The surface mount device 10 is attached to the structure 12 by electrically attaching the contact pads 14 of the surface mount device 10 to the contact pads 16 of the structure 12 using attach material 28 having filler 30 . The attach material 28 may be any conductive material suitable for attachment of the surface mount device 10 to the mounting structure 12 , such as but not limited to solder or conductive epoxy. The filter 30 may be any of a number of conductive or non-conductive materials having a melting point greater than a melting point of the attach material 28 . These materials include but are not limited to silica, copper, aluminum oxide, tin, lead, gold, silver, indium, nylon, plastic, nickel, or carbon, and may be used individually or in combination. In addition, the filler 30 is preferably a relatively solid and granular shaped material having sufficient rigidity to support the surface mount device 12 in the presence of expected and/or unexpected external forces.
Mounting the surface mount device 10 to the structure 12 is achieved by placing the attach material 28 including the filler material 30 on the contact pads 14 of the surface mount device 10 . Optionally, the attach material 28 including the filler material 30 may be placed on both the contact pads 14 of the surface mount device 10 and the contact pads 16 of the mounting structure 12 . As another option, the attach material 28 including the filler material 30 may be placed only on the contact pads 16 of the mounting structure 12 . The contact pads 14 of the surface mount device 10 are aligned with the contact pads 16 of the structure 12 , and the surface mount device 10 is placed onto the mounting structure 12 . As the surface mount device 10 settles into the attach material 28 , the movement of the surface mount device 10 towards the structure 12 is limited by the filler material 30 . Once settled, a distance between the surface mount device and the structure is defined by the diameter of the filler material 30 .
FIG. 3 illustrates the surface mount device 10 attached to the mounting structure 12 via the contact pads 14 and 16 using the attach material 28 . As illustrated, the filler 30 , and more specifically the diameter of the filler 30 , defines the distance d between the surface mount device 10 and the structure 12 . The diameter of the filler 30 corresponds to the cross-sectional diameter of the filler 30 , wherein the filler 30 may have any cross-sectional shape including but not limited to circular, square, rectangular, or polygonal. In one embodiment, the diameter of the filler 30 is in the range including 50 micrometers to 100 micrometers. However, it is important to note that the filler 30 can have any diameter, and the diameter of the filler 30 depends on the details of the particular design. Therefore, according to the present invention, the distance d between the surface mount device 10 and the structure 12 is controlled by the diameter of the filler 30 in the attach material 28 .
The ability to control the distance d is advantageous for many reasons. As discussed previously, if the distance d is unpredictable, the contact pads 14 of the surface mount device 10 may become shorted. The attachment material 28 having the filler 30 controls the distance d such that the distance d is sufficient to prevent the shorting of the contact pads 14 caused by gravity and the placement of the surface mount device 10 . Controlling the distance d may also be beneficial for many radio frequency applications by reducing interference and noise. Another advantage is that the controlled distance d allows soldering residue to be cleaned from beneath the surface mount device 10 . In addition, the controlled distance d allows the area between the surface mount device 10 and the structure 12 to be accurately filled with underfill material, which will be described in detail below.
FIG. 4 illustrates another embodiment of the present invention in which the attach material 28 including the filler 30 may be used in combination with a non-conductive underfill material 32 to improve a moisture sensitivity level (MSL) performance of the surface mount device 10 . Typically, solder (not shown) without filler 30 is used for mounting the surface mount device 10 to the structure 12 via the contact pads 14 and 16 , thereby causing the distance d to be unpredictable and making it very difficult to encapsulate or insert the underfill material 32 between the surface mount device 10 and the structure 12 . The difficultly in inserting the underfill material 32 may cause an opening in the underfill material 32 that creates an open path between the contact pads 14 of the surface mount device 10 and/or the contact pads 16 of the structure 12 . The opening may allow moisture to accumulate between the surface mount device 10 and the structure 12 . When the solder is reheated, the moisture turns to steam and forces its way out of the device causing delamination and solder reflow. Further, the solder may flow through the opening when reheated and may short the contact pads 14 of the surface mount device 10 .
According to the present invention, the attach material 28 including the filler 30 controls the distance d between the surface mount device 10 and the structure 12 . By controlling the distance d, the area between the surface mount device 10 and the structure 12 can be accurately filled with underfill material 32 . The controlled distance d allows the underfill material 32 to be inserted such that there is no opening creating a path between the contact pads 14 of the surface mount device 10 and/or the contact pads 16 of the structure 12 . Therefore, the contact pads 14 of the surface mount device 10 and/or the contact pads 16 of the structure 12 cannot be shorted during reflow.
The embodiment illustrated in FIG. 4 has an area defined by the surface mount device 10 , the structure 12 , and the attach material 28 is filled with the non-conductive underfill material 32 . However, it is important to note that the underfill material 32 is optional and is not necessary to prevent the shorting of the contact pads 14 of the surface mount device 10 .
Those skilled in the art will recognize improvements and modifications to the preferred embodiments of the present invention. All such improvements and modifications are considered within the scope of the concepts disclosed herein and the claims that follow. | The present invention relates to electrically attaching a surface mount device to mounting structure via their respective contact pads using an attach material, such as solder or conductive epoxy, which includes a filler material. In general, the filler material is relatively solid and granular shaped, wherein the diameter of the filler material controls a mounting distance between the surface mount device and the mounting structure. The filler allows a desired distance to be maintained during initial placement of the surface mount device and any subsequent reheating. | 8 |
This application is a continuation of International Application No. PCT/JP2009/054857 filed Mar. 13, 2009, which claims priority to Japanese Patent Document No. 2008-071479, filed on Mar. 19, 2008. The entire disclosures of the prior applications are herein incorporated by reference in their entireties.
BACKGROUND
The present invention relates to processing apparatuses which perform a substrate processing while transferring a substrate.
Conventionally, a substrate transfer apparatus (such as, a moving stage) has been used in performing a substrate processing while moving a processing unit such as a print head, and a substrate relative to each other.
In such a substrate transfer apparatus, the flatness and smoothness of a mounting surface for mounting a substrate is required in order to control a positional relationship between the processing unit and the substrate with high accuracy. Conventionally, the required flatness was around 100 μm, while in recent years a higher flatness (50 μm or less) has been required.
A method is known wherein a material (such as, granite) having a high hardness, is polished to form a substrate-mounting table.
However, granite is heavy in weight, and in order to move the substrate-mounting table at a high speed, a high-power moving unit and a control unit are required, thereby resulting in an increase in equipment cost and running cost (driving power or the like). Moreover, with an increase in the size of the substrate in recent years, the size of the mounting table has also increased; and thus, a reduction in the weight of the mounting table has been further required.
If the thickness of the mounting table made of granite is reduced, the strength of the mounting table decreases although the weight thereof can be reduced. Moreover, if the mounting table is thinned, the mounting table will bend when the mounting table is supported by a support shaft which is disposed upright on an air bearing (or wheel).
In order to improve the flatness of the mounting surface, prior to attaching the mounting table to the support shaft, the mounting table is usually disposed in a processing table, which is wider than the mounting table so as to polish the mounting surface. However, even if the flatness of the mounting surface is set 50 μm or smaller by polishing, and when the mounting table bends due to its attachment to the support shaft, the flatness of the mounting surface will exceed 50 μm.
Such problems are disclosed in, for example, JPA No. 07-311375 and JPA No. 2005-114882.
SUMMARY OF THE INVENTION
The present invention has been made to solve the above-described problems. An object of the present invention is to provide a light-weight mounting table having high surface flatness.
In order to solve the above-described problems, according to an aspect of the present invention, a substrate transfer processing apparatus comprises a track for a substrate, a travel device for a substrate which moves along the track for a substrate and a mounting table which is attached to the travel device for a substrate and a substrate is disposed on a surface of the mounting table. The mounting table includes a plate-shaped main body made of granite and at least one recessed part which is formed by excavating a rear surface of the plate-shaped main body, and the mounting table is supported outside the recessed part, and the substrate is disposed on a surface of the plate-shaped main body opposite to a surface in which the recessed part is formed.
According to another aspect of the present invention, a substrate transfer processing apparatus further comprises a track for processing, a travel device for processing which moves along the track for processing and a processing unit attached to the travel device for processing, each of the track for a substrate and the track for processing being linear-shaped. A direction in which the track for a substrate extends and a direction in which the track for processing extends are perpendicular to each other; and an area where the substrate moves and an area where the processing unit moves overlap with each other.
According to yet another aspect of the present invention, there is provided a substrate transfer processing apparatus, wherein the processing unit includes a print head, and wherein the print head includes a discharge orifice which discharges a processing liquid toward the substrate disposed on the mounting table.
According to yet another aspect of the present invention, there is provided a substrate transfer processing apparatus such that the processing unit is an inspection unit for inspecting the substrate disposed on the mounting table.
The substrate transfer processing apparatus of the present invention is configured as described above, and the mounting table is lightweight as compared to a mounting table of which the recessed part is not formed because of the weight of the formed recessed part; and the equipment cost and running cost of a moving device for moving the mounting table are low.
Because a protruding part (rib) remains around the recessed part, the strength of the mounting table is higher than a case where the board thickness of the mounting table is simply reduced.
If the recessed part is formed in the mounting table, the mounting table is likely to bend when the mounting table is supported by a supporting member, as compared to a case where the recessed part is not formed. If the mounting table is left in the same state such that the mounting table is supported by the supporting member, and the surface of the mounting table on which a substrate is disposed is polished so as to be flat. Then, the surface of the mounting table is flat when the mounting table is actually supported by the supporting member.
Since the mounting table is lightweight, the mounting table can be easily handled and the facility cost and running cost of the moving device for moving the mounting table are also low. The strength of the mounting table is high as compared to a case where the thickness is simply reduced. Since the mounting table is made of granite, a flat and smooth mounting surface can be formed by polishing. Since the mounting surface is flat, the positional relationship between a substrate and the processing unit can be controlled with high accuracy and a desired position of the substrate can be processed accurately.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view illustrating an example of a substrate transfer processing apparatus of the present invention.
FIG. 2 is a cross-sectional view illustrating the example of the substrate transfer processing apparatus of the present invention.
FIG. 3 is a plan view illustrating a first example of a mounting table.
FIG. 4 is a plan view illustrating a second example of the mounting table.
FIG. 5 is a plan view illustrating a third example of the mounting table.
FIGS. 6( a ) to 6 ( e ) are cross-sectional views illustrating the steps of manufacturing the mounting table.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a plan view of a substrate transfer processing apparatus 1 which is an example of a processing apparatus of the present invention; and FIG. 2 is a cross-sectional view along line A-A of FIG. 1 .
The substrate transfer processing apparatus 1 includes a pedestal 10 , a track 11 for a substrate disposed on the pedestal 10 , a travel device 21 for a substrate disposed on the track 11 for a substrate, and a mounting table 40 attached to the travel device 21 for a substrate.
Each track 11 for a substrate includes at least one rail 15 .
The rail 15 of the track 11 for a substrate linearly extends on the surface of the pedestal 10 . If the number of rails 15 of the track 11 for a substrate is two or more, the extension directions of the respective rails 15 are parallel to each other.
The travel device 21 for a substrate includes an air bearing 23 disposed on the rail 15 and a support shaft (support member) 25 having a lower end which is attached to the air bearing 23 .
The number of air bearings 23 is three or more, and one or more air bearings 23 are disposed in each rail 15 .
Accordingly, the number of support shafts 25 is also at least three, and at least one support shaft 25 is disposed above the rail 15 .
The mounting table 40 is attached in contact with the upper ends of three or more support shafts 25 , and is supported above the rail 15 by the support shaft 25 .
The air bearing 23 is connected to a gas supply system 17 (such as, an air compressor); and the gas of the gas supply system 17 is supplied to the air bearing 23 .
An ejection hole (not shown) is provided in the surface of the air bearing 23 on the rail 15 side; and the gas supplied to the air bearing 23 is ejected from the ejection hole toward the surface of the rail 15 so that the air bearing 23 floats from the rail 15 and the mounting table 40 floats while being supported by the support shaft 25 .
The surface of the rail 15 on which the air bearing 23 is disposed is horizontal. The gas supply amount of the gas supply system 17 is set so that each of the lower ends of the respective air bearings 23 floats by the same distance from the surface of the rail 15 .
The height from the lower end of each air bearing 23 to the upper end of the support shaft 25 is set to be identical; and accordingly, the upper end of the support shaft 25 (i.e., a portion where the support shaft 25 is in contact with the mounting table 40 ) is located within a horizontal plane parallel to the surface of the rail 15 .
The mounting table 40 includes a plate-shaped main body 41 and a recessed part 45 formed in one surface (rear surface 47 ) of the plate-shaped main body 41 , with a front surface (mounting surface 46 ) directed upward and the rear surface 47 directed downward; and the upper end of the support shaft 25 is attached in contact with the outer portion (the protruding part around the recessed part: rib) of the recessed part 45 in the rear surface 47 .
Even if the mounting table 40 bends when the mounting table 40 is supported by the support shaft 25 , the mounting surface 46 becomes flat as discussed later. Here, the mounting surface 46 is horizontal and the substrate 7 is horizontally disposed in close contact with the mounting surface 46 .
A groove 42 is formed in an area of the mounting surface 46 where the substrate 7 is disposed; and the substrate 7 is in close contact with an outer portion of the groove 42 of the mounting surface 46 so that the opening of the groove 42 is covered with the substrate 7 . The internal space of the groove 42 is connected to an exhaust system (not shown); and if the interior of the groove 42 is evacuated by the exhaust system, the substrate 7 is sucked to the mounting surface 46 due to a pressure difference.
The travel device 21 for a substrate travels by a moving device 31 while the mounting table 40 is horizontally supported. The moving device 31 includes a stationary magnet unit 33 and a movable magnet unit 35 , for example. The stationary magnet unit 33 includes a plurality of magnets disposed along the extension direction of the rail 15 ; and magnetic poles with different polarities are formed on the surfaces of adjacent magnets to each other.
The movable magnet unit 35 (motor coil) is attached to the mounting table 40 . The movable magnet unit 35 faces a part of the stationary magnet unit 33 . If an AC voltage is applied to the movable magnet unit 35 in a state such that the mounting table 40 is floated, the mounting table 40 moves along the extension direction of the track 11 for a substrate above the track 11 for a substrate.
The surface of the air bearing 23 is horizontal. The gas supply amount from the gas supply system 17 is set such that the distance between the air bearing 23 and the surface of the rail 15 always becomes constant. Accordingly, the mounting table 40 moves within the horizontal plane; and the substrate 7 also moves within the horizontal plane. If the application of an AC voltage to the movable magnet unit 35 is stopped, the mounting table 40 stops.
A track for processing 55 is disposed at a position above the mounting table 40 . The track for processing 55 includes at least one rail 56 ; and the extension direction of each rail 56 is perpendicular to the extension direction of the rail 15 of the track 11 for a substrate.
A travel device for processing 22 is disposed on the track for processing 55 , and a processing unit 50 (here, a print head) is attached to the travel device for processing 22 . The travel device for processing 22 travels on the rail 56 by a moving device 32 ; and the processing unit 50 moves along the extension direction of the rail 56 . Accordingly, the moving direction of the mounting table 40 is perpendicular to the moving direction of the processing unit 50 .
The track 11 for a substrate crosses the track for processing 55 under the track for processing 55 and both ends of the track 11 in the extension direction protrude from an area where the processing unit 50 moves.
Reference numeral 6 of FIG. 1 denotes a processing area which is a part of an area where the processing apparatus 50 moves, and located right above the track 11 for the substrate.
Among two portions protruding from the processed area 6 of the track 11 for a substrate, one portion is defined as a start position and the other one is defined as a turn-back position, wherein the mounting table 40 moves back and forth between the start position and the turn-back position.
A substrate lifting mechanism (not shown) is disposed at the start position. For example, the substrate lifting mechanism includes a lifting pin (not shown); and the mounting table 40 has through-holes (not shown) into which the lifting pin can be inserted. The lifting pins move vertically inside the through-holes of the mounting table 40 which stands still at the start position; and the substrate 7 is placed on the upper end of the lifting pin and is detached from the mounting table 40 .
The substrate 7 is placed on the mounting surface 46 at the start position, and the mounting table 40 moves back and forth under the processed area 6 ; and then, the substrate 7 is removed after its return to the start position. Accordingly, an area where the substrate 7 travels overlaps with an area where the processing unit 50 travels; and the substrate 7 crosses the processed area 6 under the processed area 6 .
The track for processing 55 crosses the track 11 for a substrate above the track 11 for a substrate; and both ends thereof in the extension direction protrude from the track 11 for a substrate. The processing unit 50 moves back and forth between one of the portions of the track for processing 55 protruding from the track 11 for a substrate and the other portion; and the processing unit 50 faces the substrate 7 which crosses the processed area 6 while moving back and forth.
The processing unit 50 includes a head main body 51 and at least one print head 52 . The print head 52 includes at least one discharge orifice 53 and is attached to the head main body 51 with the discharge orifice 53 directed downward.
Each print head 52 is connected to a coating liquid supply system 58 ; and coating liquid (such as, ink, spacer dispersion liquid, or the like) supplied from the coating liquid supply system 58 is supplied to each print head 52 and is discharged from the discharge orifice 53 .
The substrate 7 faces the processing unit 50 under the processed area 6 ; and the coating liquid lands on the surface of the substrate 7 so as to coat the same. On the surface of the substrate 7 , a portion to be processed to which the coating liquid is to be applied is determined in advance.
The length of the portion to be processed along the moving direction of the processing unit 50 is longer than the length of an area where the processing unit 50 can apply the coating liquid at a time.
The substrate 7 is disposed under the travel area of the processing unit 50 , and the processing unit 50 is caused to travel so as to cross the travel area above the substrate 7 (forward movement) while discharging coating liquid, then the coating liquid is applied from one end of the portion to be processed in the moving direction of the processing unit 50 to the other end.
If the length of portion to be processed along the moving direction of the substrate 7 is longer than the length of an area where the processing unit 50 can apply the coating liquid at a time, after the processing unit 50 is moved forward, the substrate 7 is moved so as to dispose an unprocessed part in the portion to be processed to which the coating liquid has not been applied at just under the travel area of the processing unit 50 .
In such a state, when the processing unit 50 is caused to travel in the backward direction which is an inverse direction to the forward movement and crosses the portion to be processed (return movement) while discharging the coating liquid, the coating liquid is applied to the unprocessed part in the portion to be processed.
When the processing unit 50 crosses the portion to be processed and the movement of the substrate 7 are repeated, the coating liquid can be applied to the whole portion to be processed.
For the processing unit's 50 crossing of the portion to be processed, the processing unit 50 may be caused to travel while discharging the coating liquid, or the discharging of the coating liquid and the traveling of the processing unit 50 may be alternately repeated.
The printing unit is not limited in particular, and other coating unit (such as, a roll coater or a dispenser) can be used as long as it can apply the coating liquid while moving. Furthermore, the processing unit 50 is not limited to the printing unit; and the portion to be processed of the substrate 7 may be inspected (observed) using an inspection unit (such as, a microscope or a camera).
Next, the recessed part 45 of the mounting table 40 and an installation place of the support shaft 25 will be described in detail. FIG. 3 to FIG. 5 are plan views showing the recessed part 45 and an installation place P of the support shaft 25 .
As shown in FIG. 3 and FIG. 4 , the planar shape of the recessed parts 45 , 62 may be rectangular (including square or rectangle), and as shown in FIG. 5 , the planar shape of the recessed part 63 may be circular (including true circle or ellipse). Furthermore, the planar shape of the recessed part may be triangular or polygonal.
Moreover, as shown in FIG. 5 , the recessed parts 45 , 63 having different shapes may be formed in one plate-shaped main body 41 , and the recessed parts 45 , 64 having different sizes may be formed in one plate-shaped main body 41 .
The number of recessed parts 45 , 62 , and 63 may be plural as shown in FIGS. 3 and 5 , or may be one as shown in FIG. 4 .
It is preferable that the shape and size of the recessed part are determined in consideration of the center of gravity thereof and balance of the mounting table 40 . Specifically, the shape and size of the recessed part are determined so that the load on the support shafts 25 becomes uniform. Alternatively, they are preferably determined such that a rotation moment does not occur at the time of acceleration or deceleration.
The installation place where the support shaft 25 is installed is not limited in particular as long as it is in the rear surface of the plate-shaped main body 41 . However, the support shaft 25 is preferably provided in a protruding part on the outer side of the recessed part 45 because the bottom surface of the recessed part 45 is thin and its strength is poor.
As shown in FIGS. 3 and 5 , if a place where protruding parts extending between the recessed parts 45 and 63 intersect with each other is set as the installation place P, the strength will increase.
In order to stably hold the mounting table 40 , at least three installation places P are necessary, and more preferably, four or more installation places P are required. In order to provide four or more installation places P in places where the protruding parts intersect with each other, nine or more recessed parts 45 , 63 are required.
Next, a manufacturing process of the mounting table 40 will be described.
FIG. 6( a ) shows the plate-shaped main body 41 before the recessed part 45 is formed therein. The plate-shaped main body 41 is made of a granite plate.
In one surface (rear surface 47 ) of the plate-shaped main body 41 , the installation place P of the support shaft 25 described above is determined in advance. In the rear surface 47 of the plate-shaped main body 41 , a portion excluding the installation place P and the edge part is excavated in order to form the recessed part 45 ; and the installation place P and edge part are left without being excavated ( FIG. 6 ( b )). It is noted that the depth of each recessed part 45 may be the same or may be different from each other.
The number of support shafts 25 attached to the mounting table 40 is determined in advance. The same number of support shafts for polishing (support member for polishing) 12 as the support shafts 25 are disposed upright so as to locate the upper end thereof within the same flat surface (the same horizontal plane), and the plate-shaped main body 41 is placed on the support shaft for polishing 12 such that each installation place P is in contact with the support shaft for polishing 12 ( FIG. 6( c )).
Because the contact area between the support shaft for polishing 12 and the plate-shaped main body 41 is smaller than the rear surface of the plate-shaped main body 41 , a portion around the installation place P of the plate-shaped main body 41 drops below the installation place P and the plate-shaped main body 41 bends.
The shape and size of a portion (upper end) of the support shaft for polishing 12 where the support shaft for polishing 12 is in contact with the plate-shaped main body 41 have the same shape and size as that of the support shaft 25 of a portion (upper end) where the support shaft 25 is in contact with the plate-shaped main body 41 . Accordingly, the bend when the plate-shaped main body 41 is supported by the support shaft for polishing 12 is the same as that when the plate-shaped main body 41 is supported by the support shaft 25 .
In a state such that when the plate-shaped main body 41 is supported by the support shaft for polishing 12 , the mounting surface 46 is polished so as to set the flatness of the mounting surface 46 to be 16 μm or less (the height from a reference plane is in the range of +8 μm to −8 μm) (the lapping process in FIG. 6( d )).
When it is necessary to form the groove 42 and/or a hole for connecting groove 42 to the exhaust system or, the like, the mounting surface 46 is excavated so as to form groove 42 or the hole after the lapping process in a state such that the plate-shaped main body 41 is supported by the support shafts for polishing 12 ( FIG. 6( e )).
The flatness of the surface of the mounting surface 46 is measured after the formation of the groove 42 or the hole. If needed, the mounting surface 46 is polished so as to set the flatness to be 16 μm or less (finish lapping process) in a state such that the plate-shaped main body 41 is supported by the support shaft for polishing 12 . It is noted that, if the groove 42 or the hole is formed in the mounting surface 46 , the flatness of a portion where the mounting surface 46 is in contact with the substrate 7 (i.e., the flatness of a portion of an outer part of the groove 42 or hole) is set to be 16 μm or less.
The support shaft for polishing 12 is removed from the installation place P of the mounting table 40 which has been manufactured in the above-discussed processes; and the upper end of each support shaft 25 is in contact with the installation place P, thereby the mounting table 40 being attached to the support shaft 25 .
As discussed above, the shape and size of a portion where the support shaft for polishing 12 is in contact with the mounting table 40 are similar to the shape and the size of the support shaft 25 ; and the installation place P where the support shaft for polishing 12 is attached to the mounting table 40 is also similar to the installation place P of the support shaft 25 . Accordingly, when the mounting table 40 is supported by the support shaft 25 , the mounting surface 46 has a flat surface having the flatness of 16 μm or less.
The grinding method in the lapping process and finish lapping process is not limited in particular. One example of such grinding method is a wet lapping method in which the polishing tool and the mounting surface 46 are rubbed with each other in a state such that a polishing liquid formed by dispersing abrasive grains into a solution (water, an organic solvent or the like) is interposed between a polishing tool (lapping tool) and the mounting surface 46 .
The abrasive grain is also not limited in particular, and a fine powder of diamond, silicon carbide, alumina, or the like, or a hydrophilic oxide-based abrasive grain (such as, silicon oxide, cerium oxide, zirconia, or chromium oxide) can be used.
The plate-shaped main body 41 used in the present invention is made of granite.
Metal has a high coefficient of thermal expansion and is likely to deform. If the plate-shaped main body 41 is made of a metal, even if the surface is polished to be flatten and smoothened, a deformation or a residual stress that has occurred during polishing causes a swell on the surface, and it cannot be eliminated. Moreover, ceramic is not suitable for the present invention because the surface thereof is difficult to be made flat and smooth by polishing.
Stone (mineral) (such as, granite) is most suitable for the material of the plate-shaped main body 41 of the present invention because it has a coefficient of thermal expansion lower than metal and can be polished easier than ceramic.
The material of the plate-shaped main body 41 is not limited in particular as long as it is a hard stone which does not cause a crack or the like by being excavated; and granite, marble, or the like can be used. However, granite is most suitable in terms ease in polishing.
If the plate-shaped main body 41 is made of granite, even when the recessed part 45 is excavated and also polished, the plate-shaped main body 41 will not be damaged; and further, the mounting surface 46 which is flatter and smoother than the one made of other materials can be obtained by the polishing.
The type of granite is not limited in particular, and various types (such as, China black, Indian black, Rustenburg, or Kurnool) can be used.
If a part of the plate-shaped main body 41 is made of a different material, the strength significantly decreases, and deformation is likely to occur due to a difference in the coefficients of thermal expansion. Therefore, in the plate-shaped main body 41 , all the parts from the mounting surface 46 to the rear surface 47 are preferably made of granite.
The substrate 7 can be held on the mouthing table 40 being pushed to the mounting surface 46 by a pressing member, instead of sucking.
The intersecting angle between the extension direction of the track 11 for a substrate and the extension direction of the track for processing 55 may not be the right angle as long as these extension directions intersect with each other.
The travel device for processing 22 attached to the processing unit 50 is not limited in particular. For example, similar to the travel device 21 for a substrate, the travel device for processing 22 includes the air bearing 24 disposed on the rail 56 and the support shaft (support member) 26 having its lower end attached to the air bearing 24 , the upper end of the support shaft 26 being attached to the processing unit 50 .
Moreover, the moving device 32 of the processing unit 50 is also not limited in particular; and for example, a stationary magnet unit 34 and movable magnet unit 36 similar to those of the moving device 31 of the mounting table 40 may be attached to the rail 56 and the processing unit 50 , respectively, so as to constitute the moving device 32 .
As discussed above, a case has been described where the mounting table 40 and the processing unit 50 are attached to the upper ends of the support shafts 25 , 26 so as to travel on the rails 15 , 56 , respectively. However, the present invention is not limited thereto.
For example, the sides of the support shafts 25 , 26 and opposite side to the air bearings 23 , 24 (or wheels) may be folded downward and upward, respectively; and on their folded ends, the mounting table 40 and the processing unit 50 may be placed so that the mounting table 40 and the processing unit 50 are disposed below the rails 15 , 56 .
Also in this case, a full weight load of the mounting table 40 is applied to the support shaft 25 ; and therefore, when the mounting table 40 is manufactured, the support shaft for polishing 12 is attached to the installation place P, to which the support shaft 25 is to be attached, and polishing is performed in such a state that the mounting table 40 is supported by the support shaft for polishing 12 .
The configurations of the travel device 21 for a substrate and the travel device for processing 22 are also not limited in particular; and instead of the air bearings 23 and 24 , a wheel may be attached to the support shafts 25 and 26 , respectively. If the wheel is used instead of the air bearings 23 and 24 , the moving devices 31 and 32 are set as motors for rotating this wheel.
As discussed above, a case has been described such that each of the substrate 7 and the processing unit 50 is moved. However, the present invention is not limited thereto. For example, a rail is extended on the surface of the pedestal 10 , and the track 11 for a substrate is disposed so as to be perpendicular to this rail. If the track 11 for a substrate is moved along a rail perpendicular to the extension direction of the track 11 , then the substrate 7 will move in two directions (i.e., the direction along the track 11 for a substrate and the direction perpendicular to the track 11 for a substrate); and therefore, it is not necessary to move the processing unit 50 .
In order to prevent the occurrence of the derailment from the track 11 for a substrate, a derailment-preventing device 27 as shown in FIG. 2 may be attached to the mounting table 40 . The derailment-preventing device 27 includes two or more air bearings 29 attached to the mounting table 40 , for example. Since the air bearing 29 is located on both sides of the rail 15 and is pushed against the rail 15 by a spring member 28 from both sides, the mounting table 40 does not derail from the rail 15 . | A substrate transfer processing apparatus capable of processing a substrate at high speed is provided. A mounting table on which a substrate is mounted includes a plate-shaped main body and a recessed part formed in a rear surface of the plate-shaped main body. Since the mounting table is lightweight as compared to the mounting table before the recessed part is formed therein, the load on a motor is small and the running cost is low even when the mounting table is moved at high speed. Because the plate-shaped main body is made of granite, the mounting surface can be made flat and smooth by polishing. Since the mounting surface is flat and smooth, the accuracy in positioning the substrate is high. | 8 |
CROSS REFERENCE TO RELATED PATENT APPLICATIONS
[0001] The present application is a divisional patent application of U.S. patent application Ser. No. 10/644,130 filed on Aug. 20, 2003 for a “Single Piece Packaging Container and Device for Making Same.”
BACKGROUND OF THE INVENTION
[0002] The present invention is directed to packaging containers and a device for making the containers. More particularly, the present invention pertains to configurations for a packing container having self-formed end closures, created from a single piece of material. The present invention also pertains to a device for forming the containers.
[0003] Packaging for lengthy items takes many forms. One construction includes a pair of corrugated, laminated paperboard top and bottom U-shaped channels configured for one to fit within the other. Most packages formed in this manner require separate end closures or caps, usually manufactured from cardboard or wood. These caps generally are stapled to adjacent package walls. Not only does this method necessitate close-fit manufacturing, but it is also very cumbersome at installation, and may cause content damage due to incompletely formed or off-positioned staples.
[0004] In another variety of packaging container, one of the top and bottom U-shaped channels has a notch cut into opposing side walls of the “U,” so that the “U” portion may be folded over at a 90 degree angle. In such a configuration, channel ends are closed by the folded base portion and the side walls of the “U,” which are folded over adjacent side walls. To seal such a package, tape or a like strip-type adhesive sealant must be extended over the flaps that then are folded over the adjacent side walls. Even though a seal may be formed, openings may remain at the juncture of the folded-over base portion and the cover portion, seriously weakening the package. This design is disclosed in U.S. Pat. No. 4,976,374.
[0005] Another existing packaging container, disclosed in Loeschen, U.S. Pat. No. 6,382,447, resolves the above-referenced problems by providing a packaging container in which the entirety of the end closure is formed from the packaging material itself. However, the container base unit, which forms end closures for the packaging container, features mitered corners. These mitered corners require complex die-cutting with mirrored tools, and mandatory strapping at specific positions to restrain the miter flaps. The patent to Loeschen, which is commonly assigned herewith, is incorporated herein by reference.
[0006] A new, single-piece packaging container cut without miters is disclosed in application Ser. No. 10/264,506, filed Oct. 4, 2002, assigned to the assignee of the present invention and incorporated herein by reference. The end closures of this packaging container are formed from the packaging material itself. The container allows for no gaps at its closure locations, because its end closures meet or overlap along the container's main body portion, providing a high degree of structural strength and package integrity. Manufacturing the container is extremely simple and cost-effective, requiring only two straight saw-cuts on each package end.
[0007] Occasionally, packaging containers must accommodate objects with varied local height elevations, or objects that require segregation during shipping or storage. Normally, shippers rely on foam fillers or container partitions to protect such irregularly shaped or fragile objects. Foam fillers may compress, leak, or shift, and container partitions may shift or break during shipping, rendering shippers' attempts to protect their products worthless. Accordingly, there exists a need for specialized configurations for a single-piece packaging container having self-formed end closures, providing better protection for fragile and/or irregularly shaped objects than undependable foam fillers or container partitions.
BRIEF SUMMARY OF THE INVENTION
[0008] Configurations for a packing container formed from a single, preformed, rigid unit of U-shaped cross-section having a main body portion with a bottom wall and opposing side walls, and having self-formed end closures are disclosed. The unit forms a plurality of end closures, at each end of the packaging container. Each end closure is formed from a plurality of closure panels extending from and adjacent to each end of the main body portion. The main body portion and the plurality of end closures are separated from one another by fold lines.
[0009] For purposes of the present disclosure, the package material, although defined as having a U-shaped cross-section is, in fact, formed from a material having a channel-like or squared U-shape having a flat or near-flat bottom wall. The corners may be formed having a radius of curvature (i.e., rounded) or they may be formed having relatively sharp angles. However, again, for purposes of the present disclosure, the container material is referred to as “U-shaped.”
[0010] The main body portion and the plurality of closure panels all have straight-cut corners at their junctions with each other. Some closure panels are configured for folding generally perpendicular to each other and to the main body bottom wall, and others are configured for folding generally parallel to each other and to the main body bottom wall.
[0011] In one embodiment, the packaging container is configured to enclose an object with an elevated end (e.g., a support post with an attached asymmetrical flange). One of the end closure's closure panels has approximately the same height as the elevated end of the object to be packaged. Another embodiment is configured to enclose an object with an elevated mid-section (e.g., a crankshaft with integrated cam). Additional closure panels are included with this configuration, to accommodate the “bulge” made by the object's elevated mid-section.
[0012] In another embodiment, the packaging container is configured to enclose an object with random elevations. Two of the end closure's closure panels have approximately the same height as the highest elevation of the object to be packaged. A fourth embodiment is configured to enclose two or more dissimilar objects that should be prevented from touching or intermingling during shipping in separate compartments. Another embodiment is configured to combine elements of the four above-referenced configurations, allowing a user to ship objects with elevated ends, elevated mid-sections, or random elevations in separate compartments. A sixth embodiment is configured to enclose one or more objects with a set of two closure panels that are about equal in length to one another.
[0013] These and other features and advantages of the present invention will be apparent from the following detailed description, in conjunction with the appended claims.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0014] The benefits and advantages of the present invention will become more readily apparent to those of ordinary skill in the relevant art after reviewing the following detailed description and accompanying drawings, wherein:
[0015] FIG. 1 is a side view of a configuration for a single-piece packaging container with straight-cut end closures constructed in accordance with the principles of the present invention, the container being shown with its first, second, and third closure panels laid open, prior to folding and securing;
[0016] FIG. 2 is a side view of the configuration of FIG. 1 , showing the packaging container enclosing an object with an elevated end;
[0017] FIG. 3 is a side view of another configuration for single piece packaging container with straight-cut end closures constructed in accordance with the principles of the present invention, the container being shown with its first, second, and third closure panels laid open, prior to folding and securing;
[0018] FIG. 4 is a side view of the configuration of FIG. 3 , showing the packaging container enclosing an object with an elevated mid-section;
[0019] FIG. 5 is a side view of another configuration of a single piece packaging container with straight-cut end closures constructed in accordance with the principles of the present invention, the container being shown with its first and second closure panels laid open, prior to folding and securing;
[0020] FIG. 6 is a side view of the configuration of FIG. 5 , showing the packaging container enclosing an object with random elevations;
[0021] FIG. 7 is a front view of the configuration of FIG. 5 along line 7 - 7 , showing the packaging container enclosing an object with random elevations;
[0022] FIG. 8 is a side view of another configuration of a single piece packaging container with straight-cut end closures constructed in accordance with the principles of the present invention, the container being shown with its first, second, and third closure panels laid open, prior to folding and securing;
[0023] FIG. 9 is a side view of the configuration of FIG. 8 , showing the packaging container enclosing two objects in two separate compartments;
[0024] FIG. 10 is a side view of another configuration of a single piece packaging container with straight-cut end closures constructed in accordance with the principles of the present invention, the container shown enclosing two objects, one with an elevated end, and the other with an elevated mid-section, in two separate compartments;
[0025] FIG. 11 is a side view of another configuration of a single piece packaging container with straight-cut end closures constructed in accordance with the principles of the present invention, the container being shown with its first and second closure panels laid open, prior to folding and securing;
[0026] FIG. 12 is a side view of the configuration of FIG. 11 , showing the packaging container enclosing an object;
[0027] FIG. 13 is a perspective view of one device for forming the cuts in the packaging container material;
[0028] FIG. 14 is a perspective view of one exemplary container having cuts formed therein;
[0029] FIG. 15 is a cross-sectional view taken along line 15 - 15 of FIG. 14 , illustrating a pair of embossings formed in the container material for enhanced container formation;
[0030] FIG. 16 is a perspective view of the cutter carriage shown with the carriage in the up or loading position;
[0031] FIG. 17 is a side view of the cutter carriage of FIG. 16 shown with the carriage moving into the down or cutting position;
[0032] FIG. 18 is a partial side view of the cutter shown with a container loaded therein and with the holding pins securing the container within the cutter;
[0033] FIG. 19 is a cross-sectional view taken along line 19 - 19 of FIG. 18 ;
[0034] FIG. 20 is a partial side view of the carriage;
[0035] FIG. 21 is a perspective view of the cutter showing the indexing assembly in the retracted position;
[0036] FIG. 22 is a perspective view of the cutter similar to FIG. 21 but showing the indexing assembly in the extended position; and
[0037] FIG. 23 is a front view of the cutter showing the scale windows through a lower portion of the carriage and the scale visible therethrough.
DETAILED DESCRIPTION OF THE INVENTION
[0038] While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described presently preferred embodiments with the understanding that the present disclosures are to be considered exemplifications of the invention and are not intended to limit the invention to the specific embodiments illustrated.
[0039] It should be further understood that the title of this section of this specification, namely, “Detailed Description Of The Invention,” relates to a requirement of the United States Patent Office, and does not imply, nor should be inferred to limit the subject matter disclosed herein.
[0040] Referring now to the figures and in particular FIG. 1 , there is shown a packaging container 10 , configured to enclose an object with an elevated end (e.g., a support post with an attached asymmetrical flange) in one of the embodiments of the present invention. The packaging container is formed in a U-shaped cross-section. Preferably, the packaging container is formed from laminated paperboard material. The packaging container includes a main body portion 12 , first closure panels 14 , 16 , second closure panels 18 , 20 , and a third closure panel 22 . The straight-cut first, second, and third closure panels are formed from an extension of the main body portion 12 . The main body portion has a bottom wall 24 and side walls 26 . The first, second, and third closure panels 14 , 16 , 18 , 20 , and 22 , also have bottom walls 28 , 30 , and 32 , and side walls 34 , 36 , and 38 .
[0041] The first closure panels 14 , 16 are formed adjacent to and at either end of the main body portion 12 . The side walls 34 of the first closure panels 14 , 16 have first straight-cut corners 40 . The main body side walls 26 also have straight-cut corners 42 , immediately adjacent to the first panels' straight-cut corners 40 . First fold lines or creases 44 can be formed between the main body bottom wall 24 and the firs closure panels' bottom walls 28 at the junctures of the straight-cut corners 42 , 44 to facilitate folding.
[0042] The second closure panels 18 , 20 are adjacent to the first closure panels 14 , 16 . The second closure panels 18 , 20 are separated from the first panels 14 , 16 by second fold or crease lines 46 formed between the first closure panels' bottom walls 28 and the second closure panels' bottom walls 30 , parallel to the first fold lines 44 . The side walls 36 of the second closure panels 18 , 20 include first straight-cut corners 48 at the junctures with the first closure panels 14 , 16 . The side walls 34 of the first closure panels 14 , 16 include second straight-cut corners 50 adjacent to the second closure panels 18 , 20 .
[0043] The third closure panel 22 is adjacent to one of the second closure panels 18 . The third closure panel 22 is separated from the second panel 18 by third fold or crease lines 52 formed between the second closure panel's bottom walls 30 and the third closure panel's bottom walls 32 , parallel to the first and second fold lines 44 , 46 . The side walls 38 of the third closure panel 22 include straight-cut corners 54 at the junctures with the second closure panel 18 . The side walls 36 of the second closure panel 18 include second straight-cut corners 56 adjacent to the third closure panel 22 .
[0044] The height h 26 of the main body side walls 26 is about equal to the heights h 34 , h 36 , and h 38 of the first closure panels side walls 34 , second closure panels side walls 36 , and third closure panels side walls 38 . The length l 14 of one of the first closure panels 14 is approximately equal to the height h 52 of the object 52 (see FIG. 2 ) with an elevated end enclosed within the package 10 . The length l 16 of the other first closure panels 16 is approximately equal to the heights h 20 , h 34 , h 36 , and h 38 of the main body, first closure panels, second closure panels, and third closure panel side walls 20 , 34 , 36 , and 38 .
[0045] Referring to FIG. 2 , assembling the package 10 is straightforward and readily carried out. The package 10 is placed on a surface, with the main body 12 , and the first, second, and third closure panels 14 , 16 , 18 , 20 , and 22 , laid out flat. The article to be packaged 58 is placed in the main body portion 12 . The first panels 14 , 16 are then folded upwardly, so that the first panels 14 , 16 are perpendicular to the bottom wall 24 of the main body portion 12 . As the first panels 14 , 16 are folded, their side walls 34 can be inserted between the main body side walls 26 . The second panels 18 , 20 are then folded over, perpendicular to the first panels 14 , 16 , so that the bottom walls 30 of the second panels 18 , 20 lie substantially parallel to the bottom wall 24 of the main body portion 12 . As the second panels 18 , 20 are folded, their side walls 36 can be inserted between the side walls 34 of the first panels 14 , 16 . Finally, the third panel 22 is folded, generally perpendicular to the first closure panels 14 , 16 , generally parallel to the main body bottom wall 24 , and overlapping one of the second closure panels 20 . As the third panel 22 is folded, its side walls 38 can be inserted between the side walls 26 of the main body portion 12 . FIG. 2 shows the package 10 fully assembled and enclosing an object 58 with an elevated end. One of the corners 50 of one of the first closure panels 14 and one of the corners 48 of one of the second closure panels 18 may be trimmed to facilitate package forming.
[0046] Another embodiment of the present invention is displayed in FIGS. 3 and 4 , which show a packaging container configuration designed to enclose an object with an elevated mid-section 60 (e.g., a crankshaft with an integrated cam). Similar to the configuration shown in FIGS. 1 and 2 , the packaging container 10 includes a main body portion 12 , first closure panels 14 , 16 , and second closure panels 18 , 20 , but the present embodiment incorporates two third closure panels 22 , 23 instead of one. The lengths l 14 , l 16 of the first closure panels 14 , 16 are approximately equal to the heights h 26 , h 34 , h 36 , and h 38 of the main body, first closure panels, second closure panels, and third closure panel side walls 26 , 34 , 36 , and 38 .
[0047] Referring to FIG. 4 , to assemble the package, the main body 12 , and the first, second, and third closure panels 14 , 16 , 18 , 20 , 22 , and 23 are laid out flat on a surface. The article to be packaged 60 is placed in the main body portion 12 . The first panels 14 , 16 are then folded upwardly, so that the first panels 14 , 16 are perpendicular to the bottom wall 24 of the main body portion 12 . As the first panels 14 , 16 are folded, their side walls 34 can be inserted between the main body side walls 26 . The second panels 18 , 20 are then folded over at roughly a 45-degree angle to the first panels 14 , 16 , so that the bottom walls 30 of the second panels 18 , 20 lie at substantially at 45-degree angle to the bottom wall 24 of the main body portion 12 . As the second panels 18 , 20 are folded, their side walls 36 can be inserted between the side walls 34 of the first panels 14 , 16 . Finally, the third panels 22 , 23 are folded, generally at a 45-degree angle to the second closure panels 14 , 16 , parallel to the main body bottom wall 24 , and overlapping one another to accommodate the mid-section bulge of the object 60 . As the third panels 22 , 23 are folded, their side walls 38 can be inserted between the side walls 26 of the main body portion 12 . The second closure panels 18 , 20 may vary in length l 18 , l 20 , but together should always be equal to the length l 12 of the main body portion 12 . FIG. 4 shows the package 10 fully assembled and enclosing an object 60 with an elevated mid-section.
[0048] A third embodiment of the present invention is illustrated in FIGS. 5-7 , which show a packaging container configuration designed to enclose an object with random elevations 62 . Similar to the configurations shown in FIGS. 1-4 , the packaging container 10 includes a main body portion 12 , first closure panels 14 , 16 , and second closure panels 18 , 20 , but no third closure panels. The lengths l 14 , l 16 of the first closure panels 14 , 16 are approximately equal to the highest height of the object 62 with random elevations enclosed within the package 10 .
[0049] Two additional short slits 64 , 66 are cut into the side walls 26 of the main body portion 12 , creating small support wedges 68 , 70 . The slits 64 , 66 are positioned close to the center of the main body portion side walls 26 , and are spaced approximately two inches apart. The height h 64 , h 66 of the slits is approximately half the height h 26 of the main body portion 12 side walls 26 . Both support wedges 68 , 70 are slightly deformed inward, allowing the second closure panels 18 , 20 to rest upon them (see FIGS. 6 and 7 ) when closed.
[0050] FIGS. 6 and 7 show the packaging container 10 as assembled. The main body 12 , and the first and second closure panels 14 , 16 , 18 , and 20 are laid out flat on a surface. The article to be packaged 62 is placed in the main body portion 12 . The first panels 14 , 16 are then folded upwardly, so that the first panels 14 , 16 are perpendicular to the bottom wall 24 of the main body portion 12 . As the first panels 14 , 16 are folded, their side walls 34 can be inserted between the main body side walls 26 . The second panels 18 , 20 are then folded over, perpendicular to the first panels 14 , 16 so that the bottom walls 30 of the second panels 18 , 20 lie substantially parallel to the bottom wall 24 of the main body portion 12 . As the second panels 18 , 20 are folded, their side walls 36 can be inserted between the side walls 34 of the first panels 14 , 16 . The side walls 36 of the second closure panels 18 , 20 rest on the support wedges 68 , 70 formed in the main body side walls 26 . FIG. 6 shows the package 10 fully assembled and enclosing an object 62 with random elevations. FIG. 7 shows a front cut-away view of the package 10 fully assembled and enclosing an object 62 with random elevations.
[0051] A fourth embodiment of the present invention is demonstrated in FIGS. 8 and 9 , which show a packaging container configuration designed to enclose two related but dissimilar objects or groups of objects 72 , 74 , which should be prevented from touching or intermixing during shipping. Similar to the configurations shown in FIGS. 3 and 4 , the packaging container 10 includes a main body portion 12 , first closure panels 14 , 16 , second closure panels 18 , 20 , and third closure panels 22 , 23 . The lengths l 14 , l 16 of the first closure panels 14 , 16 and l 22 , l 23 of the third closure panels 22 , 23 are approximately equal to the heights h 20 , h 34 , h 36 , and h 38 of the main body, first closure panels, second closure panels, and third closure panel side walls 20 , 34 , 36 , and 38 .
[0052] Referring to FIG. 9 , to assemble the package, the main body 12 , and the first, second, and third closure panels 14 , 16 , 18 , 20 , 22 , and 23 are laid out flat on a surface. The articles to be packaged 72 , 74 are placed on either end of the main body portion 12 . The first panels 14 , 16 are then folded upwardly, so that the first panels 14 , 16 are perpendicular to the bottom wall 24 of the main body portion 12 . As the first panels 14 , 16 are folded, their side walls 34 can be inserted between the main body side walls 26 . The second panels 18 , 20 are then folded over, perpendicular to the first panels 14 , 16 , so that the bottom walls 30 of the second panels 18 , 20 lie substantially parallel to the bottom wall 24 of the main body portion 12 . As the second panels 18 , 20 are folded, their side walls 26 can be inserted between the side walls 34 of the first panels 14 , 16 . Finally the third panels 22 , 23 are folded, generally perpendicular to the second closure panels 18 , 20 and the main body bottom wall 24 , and generally parallel to the first closure panels 14 , 16 . As the third closure panels 22 , 23 are folded, their side walls 38 can be inserted between the side walls 36 of the second closure panels 18 , 20 . When folded, the third closure panels 22 , 23 form a double-thick divider, separating the packaged objects 72 , 74 . The second closure panels 18 , 20 may vary in length l 18 , l 20 , but together should always be equal to the length l 12 of the main body portion 12 . FIG. 9 shows the package 10 fully assembled and enclosing objects 72 , 74 that should be prohibited from touching or intermixing during shipping.
[0053] The present configuration additionally may be used as a packaging container with a built-in spacer. Frequently, objects are somewhat shorter than the length of available shipping containers. For example, it would be economical to ship an object four feet to five-and-a-half feet in length in a six-foot-long standard box. Usually, such an object would be randomly placed in a too-large box and covered with foam fillers or other, similar protective materials. However, fillers may compress, leak, or shift, leaving shipped objects without protection. Conversely, using the packaging container 10 described in FIGS. 8 and 9 , the short object could be placed against one end of the container 10 , and then custom enclosed into a segregated side, with a double-thick divider separating it from the other, fully-formed, hollow chamber. The present configuration allows shippers to customize packaging containers by creating a segregated, perfectly-sized compartment within a standard-sized box.
[0054] A fifth embodiment of the present invention is demonstrated in FIG. 10 , which shows a packaging container configuration designed to combine all four of the above described configurations. As described in detail above, the packaging container 10 exhibited in FIG. 10 can accommodate and object with an elevated end 58 , an object with an elevated mid-section 60 , an object with random elevations 62 (not shown), and objects that must be segregated during shipping 72 , 74 . To accomplish the composition of FIG. 10 , the side of the main body portion 12 containing the object with an elevated end requires four closure panels ( 14 , 18 , 22 , 76 ), and the side of the main body portion 12 containing the object with an elevated mid-section requires five closure panels ( 16 , 20 , 23 , 78 , 80 ). All of the closure panels are folded and inserted according to the above descriptions, resulting in completely object coverage and a double thick divider. If an object with random elevations 62 was packaged as part of a combination container, four closure panels would be required for its end of the container.
[0055] A sixth embodiment is presented in FIGS. 11 and 12 , which show a packaging container configuration designed to enclose one or more objects 82 . Similar to the configuration shown in FIGS. 5 and 6 , the packaging container 10 includes a main body portion 12 , first closure panels 14 , 16 , and second closure panels 18 , 20 , but no third closure panels. The lengths l 14 , l 16 of the first closure panels 14 , 16 are approximately equal to the heights h 26 , h 34 , and h 36 of the main body, first closure panels, and second closure panels side walls 26 , 34 , and 36 . In that this is a “seamless” container, the second closure panel 20 has a length l 20 that is about equal to the length l 12 of the main body portion 12 .
[0056] FIG. 12 shows the packaging container 10 as assembled. The main body 12 , and the first and second closure panels 14 , 16 , 18 , and 20 are laid out flat on a surface. The article to be packaged 82 is placed in the main body portion 12 . The first panels 14 , 16 are then folded upwardly, so that the first panels 14 , 16 are perpendicular to the bottom wall 24 of the main body portion 12 . As the first panels 14 , 16 are folded, their side walls 34 can be inserted between the main body side walls 26 . The second panels 18 , 20 are then folded over, perpendicular to the first panels 14 , 16 so that the bottom walls 30 of the second panels 18 , 20 lie substantially parallel to the bottom wall 24 of the main body portion 12 . As the second panels 18 , 20 are folded, their side walls 36 can be inserted between the side walls 34 of the first panels 14 , 16 . In that the length l 20 is about equal to the length l 12 of the main body portion 12 , the container appears to be “seamless”; that is, the container appears to be without a mid container seam across the top (which is panel 20 ) or the main body portion 12 .
[0057] Referring now to FIG. 13 , there is shown one cutter device 102 for forming or making the side wall cuts in the container 10 material. The cutter 102 includes a frame 104 , a container support 106 and a carriage 108 that moves in a reciprocating manner in the direction of the cut. As illustrated, the container support 106 includes beam 110 on which are mounted stand-offs 112 for receiving the container 10 . The container 10 rests on the stand-offs 112 to define a base surface 114 and side surfaces 116 for supporting the container 10 as it is cut.
[0058] The carriage 108 is configured to move down and up, toward and away from the container 10 as it rests on the support 106 . The carriage 108 is configured to support a pair of rotary cutters 118 , for example, circular saws, one each mounted a carriage side wall 120 . In this manner, as the carriage 108 moves up and down (as indicated by the arrow at 122 ), the cutters 118 move up and down for cutting through the side walls of the container 10 .
[0059] As best seen in FIGS. 16 and 20 , a cutting anvil 124 is positioned on the support 106 at the location at which the cutters 118 move into the container 10 . The anvil 124 includes channels 126 formed in the side walls to permit movement of the cutters 118 through the container side walls without contacting the anvil 124 side walls. In addition, the anvil 124 can include a raised portion or ridge 128 that extends transversely across the top wall 129 of the anvil 124 between the side wall channels 126 .
[0060] In a present embodiment, the carriage 108 is moved up and down by action of a drive 130 , such as the exemplary pneumatic cylinder. The pneumatic cylinder 130 is mounted to an upper carriage plate 132 to which the carriage side plates or walls 120 (mounting the cutters 118 to the carriage 108 ) are mounted. In this manner, reciprocating movement of the cylinder 130 moves the carriage 108 which moves the cutters 118 into and out of contact with the container 10 . Other drives will be recognized by those skilled in the art and are within the scope and spirit of the present invention.
[0061] The cutters 118 are fixedly mounted to the carriage 108 to permit readily moving the carriage 108 up and down for cutting the container side walls. To facilitate holding or maintaining the container 10 in place as the carriage 108 moves downward and the cutters 118 move into contact with the container side walls, a pair of holding pins 134 can be mounted to the support 106 . The holding pins 134 move outwardly to hold the container 10 side walls against the carriage side surfaces 116 as the cutters 118 make contact with the container 10 . In a present embodiment, the pins 134 are pneumatically actuated.
[0062] To further provide a “clean” container 10 appearance, the cutting device 102 is configured to emboss the container top or bottom wall 24 at fold or crease lines between the side wall cuts. As seen in FIGS. 15 and 19 , the upper carriage plate 132 includes a transverse groove 136 formed therein that corresponds to the top wall ridge 128 . In this manner as the carriage 108 moves down to move the cutters 118 into contact with the container 10 side walls, the upper plate 132 “presses” the container top (or bottom) wall 24 between the upper carriage plate 132 and the support top wall 129 , sandwiching the container wall 24 between the ridge 128 and the groove 136 , thus “embossing” a groove into the wall 24 .
[0063] To provide the appropriate spacing between cuts (e.g., to form appropriate sized panels 12 , 14 , 16 ), the cutter device 102 can include an indexing assembly 138 . The indexing assembly 138 includes a drive 140 , such as the exemplary pneumatic cylinder, to move the container 10 a desired distance once a first cut is made to position the container 10 for a second cut. To effect movement, the cylinder 140 cycles between a retracted position ( FIG. 21 ) and an extended position ( FIG. 22 ). The extension length or distance of the cylinder 140 can be set to correspond to the desired distance between cuts.
[0064] As seen in FIG. 23 , the carriage 108 can include openings or windows 142 in a side thereof that overlie a scale 144 that is applied to the support beam 110 . In this manner, the distance along the length of the container 10 at which the cut or cuts are formed can be precisely set and controlled.
[0065] All patents referred to herein, are hereby incorporated herein by reference, whether or not specifically done so within the text of this disclosure.
[0066] In the present disclosure, the words “a” or “an” are to be taken to include both the singular and the plural. Conversely, any reference to plural items shall, where appropriate, include the singular.
[0067] From the foregoing, it will be observed that numerous modifications and variations can be effected without departing from the true spirit and scope of the novel concepts of the present invention. It is to be understood that no limitation with respect to the specific embodiments illustrated is intended or should be inferred. The disclosure is intended to cover by the appended claims all such modifications as fall within the scope of the claims. | Configurations for a packing container formed from a single, preformed, rigid unit of generally U-shaped cross-section are disclosed. One configuration utilizes three end closures to enclose an object with an elevated end. Another configuration employs three end closures to enclose an object with an elevated mid-section. A third configuration uses two end closures to enclose an object with random elevations. With three end closures, a fourth configuration encloses two or more dissimilar objects in separate compartments. The fourth configuration is especially useful for items that should be prevented from touching or intermingling during shipping. A fifth configuration combines elements of the other four configurations, allowing a user to ship objects with elevated ends, elevated mid-sections, or random elevations in separate compartments. A sixth configuration encloses one or more objects with two end closures that are about equal in length to one another. A device for forming the container is also disclosed. | 8 |
This is a continuation-in-part of my application Ser. No. 09/048,964 filed Mar. 26, 1998 now U.S. Pat. No. 6,079,956.
BACKGROUND OF THE INVENTION
Manual hydraulic pumps are used in many applications in the field where electrical or other power operated pumps are not practical or economical. One such usage is in the installation of shoring which is the support structure which holds the sides of trenches during construction. The support structure consists of vertical support rails connected together by horizontal cylinders into which fluid, usually water mixed with a soluble oil or other lubricating fluid, is pumped until a desired pressure is reached, to press the vertical rails against the sides of the trench. A series of these support rail structures may be placed along the length of the trench. Each rail support structure must be individually filled with fluid and brought to a pressure to properly press against the sides of the trench to hold it in place and prevent its collapse.
This filling of the horizontal cylinders to the proper pressure is now most often done by a single cylinder manual pump submerged in a container of fluid. A quick connect coupling attaches a hose from the output of the pump to the horizontal cylinder. The pump handle is then pumped to bring the fluid. from the container into the horizontal cylinder. Until the horizontal cylinder is filled with fluid the manual pumping is quite easy. However, when the vertical rails make contact with the trench walls, the manual pumping becomes very difficult. A pressure of from 700 up to about 6000 psi, or higher, may be required, depending upon the nature of the soil, to properly put the shoring in place. It may be very difficult, for one individual to pump the fluid to the pressure required. A need exists for a pump which allows an individual operator to easily fill the fluid in the shoring to the required pressure using a small manual pump which fits into the container of fluid which is to be pumped into the shoring structure.
SUMMARY OF THE INVENTION
This invention comprises an improvement to the multi-stage manual hydraulic pump described in my parent application referenced above. It comprises a plurality of cylinders, pistons, and blocks in tandem. A block holds each cylinder assembly. One or more cylinders comprise the high volume stage, one or more cylinders comprise the medium volume stage and one or more cylinders comprise the low volume, high pressure stage. The pump may comprise as few as two stages or as many as is required to reach the desired pressure. The pump utilizes check valves built into flow tubes that control the direction of fluid. A pressure adjustable hydraulic device operated by air, fluid or a mixture thereof, in each higher volume block, automatically turns off the vacuum and flow of fluid to each higher volume cylinder at a designated pressure of pounds per square inch (psi). At the point of highest pressure only the smallest cylinder or cylinders are pumping fluid, where the effort expended is significantly reduced and the operator may effortlessly pump the amount of fluid required to reach the desired pressure in a very short span of time. The uniqueness of the pump of this invention lies in the ease and quickness in which the pump reaches its designated pressure (psi) and required volume of fluid. Using a pressure adjustable hydraulic device in each higher volume block to automatically turn off the vacuum and flow of fluid to each higher volume cylinder at a designated, but adjustable psi, allows each cylinder to switch from pumping fluid to pumping air. The hydraulic device is contolled by air, fluid or a mixture thereof, with an air and/or fluid intake valve, which allows adjustment of the resistance of the device, to change the psi at which each higher volume cylinder is disabled. The pressure can be adjusted, with each job if necessary, to minimize the work performed by the operator and the time it takes to reach optimum pressure. The highest volume cylinder assembly reaches its designated low pressure and automatically turns off first, the succeeding lower volume cylinders continue to pump fluid.
In turn, the next highest volume cylinders automatically turn off when the desired next higher pressure is reached. Thus, at the point of highest pressure, only the highest pressure, smallest volume cylinder or cylinders are pumping fluid. Because the diameter of the high pressure cylinders is relatively small, the effort expended is reduced significantly. As the pressure increases, the pump becomes increasingly easier to operate. Thus, the operation of the pump of this invention at high pressure is the opposite of what is found in existing manual pumps.
OBJECTS OF THE INVENTION
Accordingly, several objects and advantages of the invention are as follows:
It is an object of the present invention to provide a manual hydraulic pump which allows an individual to easily pump fluid to a high pressure.
Another object of the invention is to provide a simple and small manual hydraulic pump in which a single operator can pump fluid into shoring to a preselected high pressure.
Yet another object of the invention is to provide a simple, small and inexpensive manual hydraulic pump which fits into a container of liquid used to hold shoring in place in construction trenches.
Yet another object of the invention is to provide a simple, small and inexpensive multi-stage manual hydraulic pump which is adjustable as to the psi at which each higher volume cylinder is disabled.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the pump of this invention;
FIG. 2 is a perspective view of the pump of this invention, taken from the opposite side;
FIG. 3 is a side view;
FIG. 4 is a cross-section taken on lines 4--4 of FIG. 3;
FIG. 5 is a cross-section taken on lines 5--5 of FIG. 3;
FIG. 6 is a cross-section taken on lines 6--6 of FIG. 4;
FIG. 7 is a cross-section taken on lines 7--7 of FIG. 3;
FIG. 8 is a cross-section taken on lines 8--8 of FIG. 3;
FIG. 9 is a cross-section taken on lines 9--9 of FIG. 3; and
FIG. 10 is a cross-section taken on lines 10--10 of FIG. 3, after piston displacement.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings there is shown the multi-stage pump 10 of this invention placed in a vented hydraulic fluid container 11. The standard fluid container in use today in the shoring industry, holds about 5 to 7 gallons of fluid. The pump, as shown in this embodiment, comprises four blocks, upper block 12, second stage block 14, first stage block 16, third stage block 18, plus base 20. The pump as shown has three stages but could have from two to as many stages as are required to reach the desired volume and pressure. Blocks 12, 14, 16, 18, and base 20 are held together by a plurality of long bolts 30, 31, 32 and 33 which run the entire length of the pump. Spacers may be used between each block to maintain separation distances.
The pump also comprises three cyliders, the first stage or high volume cylinder 22, the second stage or medium volume cylinder 24, and the high pressure, low volume cylinder 26.
As explained in my parent application, the pump, for best operation, is bolted, by a plurality of bolts, see bolt holes 28, to the top of container 11 and container 11 is filled with a fluid such as water containing hydraulic oil, or other fluid, submerging the pump partially in the fluid. A hydraulic hose is attached, at one end to output port 35 of the pump and at the opposite end to the working shore. The description of the pump will be made with reference to its use in expanding and pressurizing shoring, although the pump could obviously be used for other purposes which require a fluid to be pumped to a high pressure.
When handle 34 is lifted (up-stroke) piston rod 36 is pulled upward, creating a vacuum in the system, exerting a compression force on spring 38 of check valve 40 in intake port 42 located in high pressure intake tube 41, opening check valve 40, allowing fluid to fill high pressure cylinder 26.
Also, on the up-stroke of piston rod 36, which has piston head 78 in cylinder 24 and piston head 80 in cylinder 22, fluid similarly also enters via intake port 68, through check valve 39, which may optionally have a spring, to tubes 54, 52, and 50 and through ports 58 and 64 into cylinders 22 and 24. When the up-stroke of piston rod 36 reaches its highest point, all of the cylinders 22, 24 and 26 are then filled with fluid, as well as tubes 50, 52 and 54 which are also filled with fluid.
On the down-stroke, fluid passes into blocks 14 and 16 through ports 55 and 61 and against pistons 56 and 62. Also on the down-stroke, fluid is pushed from cylinders 22 and 24 back through ports 58 and 64, and through check valves 63 and 65, up tubes 52 and 50 into block 12 and out output port 35. Also, on the down stroke, fluid is pushed from cylinder 26 through communication line 45 in block 18, through port 108, and through check valves 59 and 61, up tubes 48, 46, and 44 into block 12 and out output port 35.
Check valves 59, 61, 63, and 65 prevent fluid from passing back down the tubes and cylinders. Check valves 39 and 40 similarly prevent fluid from passing back through ports 42 and 68.
In the first stage of the manual pumping process all three cylinders 22, 24 and 26 are pumping high volumes of fluid into the shore to expand it as fast as possible, with the least amount of strokes. At this time the horizontal tubing of the shore is expanding quickly to meet the walls of the trench, without any resistance. Once the shore reaches the walls of the trench, the pressure inside of the pump cylinders begins to build up.
The improvement in the pump in this disclosure is that, when the fluid pressure reaches a preset level, such as 300 psi, as shown in FIG. 10, the first stage pressure control piston 56 located inside of block 16 displaces against adjustable gas and/or fluid controlled piston 90 to close input port 58 preventing all fluid from entering into high volume cylinder 22 and opens exhaust pressure release port 60 to exhaust the fluid into exhaust tubes 51 and 49, and out exhaust port 110, thus disabling high volume cylinder 22. Exhaust port 60 will remain open until the pressure falls below the predetermined fluid pressure. After all fluid has been exhausted through exhaust tube 51, only air will be pumped into and out of cylinder 22 on succeeding strokes. Exhaust port 110 may be located anywhere along the line of tubes 49 and 51.
With the first stage complete and cylinder 22 disabled, cylinders 24 and 26 continue to pump fluid. As the pump handle continues to be actuated, cylinders 24 and 26 continue to increase the system pressure until the fluid pressure reaches another level, such as 1,200 psi. When that pressure is reached, similarly to the process shown in FIG. 10, second stage pressure release piston 62 in block 14 is displaced against gas or fluid controlled piston 92 to close input port 64 preventing all fluid from entering into medium volume cylinder 24 and opens exhaust pressure release port 66 to exhaust the fluid into exhaust tube 51 and 49 and out exhaust port 110, thus disabling medium volume cylinder 24. This completes the second stage.
Optionally, pistons 90 and 92 can be replaced by a sealing device, such as an O-ring on pistons 56 and 62, sealing the gas and/or fluid on the gas and/or fluid side of pistons 56 and 62, preventing the gas and/or fluid from exiting exhaust ports 60 and 66.
The third and final stage comprises low volume, high pressure cylinder 26 continuing to pump fluid as the operator continues to pump handle 34, increasing the pressure of the system from 1,200 psi up to the required final pressure desired, which can be as high as 6000 psi, or even higher.
The difference in volume of the three stages of the pump are dependent on the exact design of the pump, however, in the embodiment shown, the high volume cylinder 22 is from about 5 cubic inches to about 7 cubic inches, the medium volume cylinder 24 from about 1 cubic inch to about 2 cubic inches and the high pressure cylinder 26 from about 0.5 cubic inches to about 1 cubic inch. The volume stated is measured by the total volume of the cylinder less the volume taken up by piston 36 located in cylinders 22 and 24 only.
Referring to FIG. 9 there is shown block 18 with high pressure cylinder 26, port 108 connected to tube 48 and communication line 45 to pass fluid from high pressure cylinder 26 through communication line 45 up tubes 48, 46, and 44 and out output port 35. Passageway 47 is needed only to machine communication line 45 and passageway 47 is plugged, once communicaion line 45 has been machined.
Input ports 42 and 68 are shown in the vertical position rather than the horizontal position shown in my parent application, however they could be in the horizontal position. All input ports may contain filters to filter out unwanted impurities that might negatively affect the operation of the pump. In the alternative, a filter could be placed around the entire outside perimeter of the pump, from block 18 down to base 20.
Gas and/or fluid input control valves 94 and 96, fitted through caps 104 and 106 are filled through lines 98 and 100, with air and/or fluid, to the pressure desired. By introducing or releasing air and/or fluid, the pressure at which each of the larger volume cylinders is disabled is adjustable within a wide range. Optionally, control valves 94 and 96 may be placed on the top of the higher volume blocks, rather than on the side as shown, which would reduce the width of the pump, providing greater clearance.
Once the shore has reached the desired pressure, the pump can be removed, so that it can be used elsewhere, by releasing the fitting on the shore, which has a check valve to hold the fluid pressure in the shore.
When it is time to remove the working shore from the trench, the pressure inside the horizontal shore cylinders is released by reattaching pump 10, then the fluid returns from the shore via port 35, through valve 74, releasing the pressure and allowing the shore to retract. To accomplish this, exhaust valve 74 located on the top of block 12 is opened to allow the fluid to flow through exhaust tubes 49 and 51 and out exhaust port 110, back into container 11. Pressure gauge 76 is provided on block 12 to constantly measure the pressure in the pump in order to achieve the preselected desired pressure in the shore.
The shore equipment must be inserted in the trench and brought to a specific preselected pressure. Too little pressure or too much pressure both will have a negative effect on maintaining the sides of the trench in a safe condition. | A multi-stage manual hydraulic pump comprising a plurality of cylinders in tandem. A block holds each cylinder assembly. One or more cylinders are the high volume stage, one or more cylinders are the medium volume stage and the final cylinders are the low volume, high pressure stage. The pump utilizes check valves built into flow tubes that control the direction of fluid. A variable hydraulic piston and cylinder assembly in each high volume block and each medium volume block automatically turns off the vacuum and flow of fluid to each cylinder at a designated pressure. At the point of highest pressure only the smallest cylinder or cylinders are pumping fluid, where the effort expended is significantly reduced. | 5 |
RELATED APPLICATION
[0001] This application is based upon prior filed copending provisional application Serial No. 60/115,532 filed Jan. 12, 1999.
FIELD OF THE INVENTION
[0002] The present invention relates to the field of semiconductor devices, and, more particularly, to a capacitor.
BACKGROUND OF THE INVENTION
[0003] Capacitors are used extensively in electronic devices for storing an electric charge. A capacitor includes two conductive plates or electrodes separated by an insulator. The capacitance, or amount of charge held by the capacitor per applied voltage, depends upon the area of the plates, the distance between them, and the dielectric value of the insulator. Capacitors may be formed within a semiconductor device, such as, for example, a dynamic random access memory (DRAM) or an embedded DRAM.
[0004] As semiconductor memory devices become more highly integrated, the area occupied by the capacitor of a DRAM storage cell is reduced, thus decreasing the capacitance of the capacitor due to a smaller electrode surface area. However, a relatively large capacitance is desired to prevent loss of stored information. Therefore, it is desirable to reduce the cell dimensions and yet obtain a high capacitance, which achieves both high cell integration and reliable operation.
[0005] Instead of forming the capacitor on the substrate surface, capacitors are also formed above the substrate, i.e., they are stacked above the substrate. The surface area of the substrate can then be used for forming transistors. For example, U.S. Pat. No. 5,903,493 to Lee discloses a capacitor formed above a tungsten plug. The tungsten plug interfaces with an interconnection line, thus allowing different layers formed above the substrate to be connected. Such plugs may be anchored or tapered to secure the plug in the dielectric layer.
[0006] Current 0.25 and 0.2 micron semiconductor technology uses metal-oxide-metal (MOM) capacitors that are formed above tungsten plugs. However, these plugs can have surface defects such as seams, recesses, bulges or other topographical features which may cause MOM capacitor reliability and yield problems. For example, when the dielectric adjacent the tungsten plug is polished during a chemical mechanical polishing (CMP) step, the resulting tungsten plug may protrude or bulge upwardly above the dielectric layer.
SUMMARY OF THE INVENTION
[0007] In view of the foregoing background, it is therefore an object of the present invention to provide an integrated circuit capacitor with metal electrodes and with increased reliability of the capacitor.
[0008] This and other advantages, features and objects in accordance with the present invention are provided by an integrated circuit capacitor including a metal plug in a dielectric layer adjacent a substrate, with the metal plug having at least one topographical defect in an uppermost surface portion thereof. A lower metal electrode overlies the dielectric layer and the metal plug. The lower metal electrode preferably comprises, in stacked relation, a metal layer, a lower metal nitride layer, an aluminum layer, and an upper metal nitride layer. A capacitor dielectric layer overlies the lower metal electrode, and an upper metal electrode overlies the capacitor dielectric layer. An advantage of this structure is that the stack of metal layers of the lower metal electrode, will prevent undesired defects at the surface of the metal plug from adversely effecting device reliability or manufacturing yield. The aluminum and metal nitride layers may also desirably provide an etch stop layer to facilitate manufacturing.
[0009] The metal plug preferably comprises tungsten, and the at least one topographical defect may include at least one of a recess, a seam and a bulge. The metal layer of the lower metal electrode preferably comprises a refractory metal such as titanium. Each of the lower and upper metal nitride layers of the lower metal electrode preferably comprises a refractory metal nitride, such as titanium nitride. Also, the upper metal electrode may comprise, in stacked relation, a lower metal nitride layer, an aluminum layer, and an upper metal nitride layer. Each of the lower and upper metal nitride layers of the upper metal electrode may also comprise titanium nitride.
[0010] The advantages, features and objects in accordance with the present invention are also provided by a method of making an integrated circuit capacitor including the steps of forming a dielectric layer adjacent a substrate and forming a metal plug in the dielectric layer. The forming of the metal plug creates at least one undesirable topographical defect in an uppermost surface portion of the metal plug. The method further includes the step of forming a lower metal electrode overlying the dielectric layer and the metal plug. The lower metal electrode may comprise, in stacked relation, a metal layer, a lower metal nitride layer, an aluminum layer, and an upper metal nitride layer. A capacitor dielectric layer is formed over the lower metal electrode, and an upper metal electrode is formed over the capacitor dielectric layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] [0011]FIG. 1 is a cross-sectional view of an integrated circuit capacitor in accordance with the present invention.
[0012] [0012]FIGS. 2, 3 and 7 - 9 are cross-sectional views illustrating the process steps for forming a capacitor in accordance with the present invention.
[0013] FIGS. 4 - 6 are enlarged cross-sectional views illustrating examples of possible defects in the surface of the metal plug of the capacitor in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, 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 be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout. The dimensions of layers and regions may be exaggerated in the figures for clarity.
[0015] Referring initially to FIG. 1, the integrated circuit MOM capacitor 20 including multilevel metal electrodes 36 , 40 above a metal plug 32 , is now described. The integrated circuit capacitor 20 is formed above a substrate 24 with an interconnect line 26 adjacent the substrate, and a dielectric layer 28 is on the interconnection line. The plug 32 is disposed in the dielectric layer 28 . The capacitor 20 includes lower and upper multilevel metal electrodes 36 , 40 and a capacitor dielectric layer 38 therebetween. The lower metal electrode 36 contacts the metal plug 32 . The second or capacitor dielectric layer 38 overlies the lower metal electrode 36 , and the upper metal electrode 40 overlies the second dielectric layer.
[0016] The lower metal electrode 36 includes multiple metal layers 52 - 58 in stacked relation. The stack includes a first metal layer 52 and preferably is formed of titanium. The first metal nitride layer 54 is preferably formed of a refractory metal nitride, such as titanium nitride. Layer 56 is a first aluminum layer and layer 58 is a second metal nitride layer also preferably formed of titanium nitride. Also, the upper metal electrode 40 also illustratively includes multiple metal layers 62 - 66 in stacked relation. Layer 62 is a third metal nitride layer and preferably is formed of a refractory metal nitride such as titanium nitride. Layer 64 is a second aluminum layer and layer 66 is a fourth metal nitride layer also preferably formed of titanium nitride.
[0017] The capacitor dielectric layer 38 overlies the lower metal electrode 36 and is formed from any suitable dielectric, e.g., silicon dioxide, silicon nitride and/or any material or alloy of material having a suitably large dielectric constant. Other suitable materials include tantalum pentoxide and barium strontium titantate, for example.
[0018] As will be described in more detail below, an advantage of this structure is that the stack of metal layers 52 - 58 of the lower metal electrode 36 , will compensate for undesired defects at the surface of the metal plug 32 . The stack will increase integrated circuit device yield, reduce MOM capacitor leakage and thus increase the reliability of the MOM capacitor 20 . Additionally, as will also be described below, the first aluminum layer 56 and the second metal nitride layer 58 are used as an etch stop when patterning and etching the capacitor dielectric layer 38 . Furthermore, the second aluminum layer 64 and the fourth metal nitride layer 66 can be used as an etch stop for a subsequent via etch.
[0019] The interconnect line 26 may include a multilayer interconnect formed on an insulating layer 42 . The insulating layer 42 is formed on or above the semiconductor substrate 24 . The semiconductor substrate 24 may include a plurality of active devices, such as transistors, which are connected together into functional circuits by the interconnect line 26 . The multilayer interconnect may include a conductive capping layer, a bulk conductor, and an electromigration barrier layer (not shown) as would readily be appreciated by those skilled in the art. Additionally, an anti-reflective coating (ARC), such as titanium nitride, may be formed on the interconnect line 26 .
[0020] The integrated capacitor 20 is electrically connected to the interconnect line 26 by the metal plug 32 . The metal plug 32 preferably includes tungsten or any suitable, electrically conductive material such as aluminum, titanium or titanium nitride.
[0021] A method for making the integrated circuit MOM capacitor 20 including the multilevel metal electrodes 36 , 40 above a metal plug 32 , as described above, will now be further discussed with reference to FIGS. 2 - 9 . Referring to FIG. 2, the semiconductor substrate 24 is preferably silicon, or may be silicon or a polysilicon layer or structure formed on the substrate. A plurality of devices, such as transistors (not shown), are formed in the substrate 24 using well known techniques. Next, the dielectric layer 42 , such as a doped or undoped silicon dioxide, is formed over the substrate 24 with well known techniques, such as thermal growth or deposition.
[0022] Next, the interconnection line 26 is formed on the dielectric layer 42 . As an example, an approximately 450 nm thick aluminum alloy layer comprising approximately 1% copper may be formed on a titanum layer using well known techniques, such as sputtering. An aluminum alloy layer has low resistivity and is readily procured; however, other low resistance materials may be used as a bulk conductor in the interconnect line 26 , as will be appreciated by those skilled in the art. As discussed above, the interconnect line 26 may be a multilayer interconnect as would readily be appreciated by those skilled in the art. Additionally, an anti-reflective coating (ARC), such as titanium nitride, may be formed on the interconnect line 26 .
[0023] The dielectric layer 28 , such as a doped silicon dioxide, is formed over the interconnect line 26 . Any well known technique can be used to form the dielectric layer 28 , such as chemical vapor deposition (CVD). Referring to FIG. 3, a photoresist layer (not shown) is formed and patterned over the dielectric layer 28 using well known photolithography techniques to define the location where a via hole 50 is to be formed. Next, the exposed portions of the dielectric layer 28 are etched. The via hole 50 is etched until the interconnect line 26 is exposed. In one embodiment, a directional reactive ion etch (RIE) is used to form the via hole 50 . The via hole 50 could be etched using standard etch conditions. Typical etchants are C 4 F 8 /CO/Ar/O 2 mixtures.
[0024] The via hole 50 is filled with a conductive material, preferably tungsten, using well known techniques for forming the metal plug 32 . Prior to forming the plug 32 , a nucleation layer, such as titanium nitride or tantalum nitride, may be sputter deposited on the side walls of the via hole 50 , as would be appreciated by those skilled in the art. Also, a thin adhesion/barrier layer, such as titanium or titanium nitride can be blanket deposited into the via hole 50 using well known techniques such as sputtering. The conductive material is deposited into the via hole 50 until the via hole 50 is filled. A chemical-mechanical polishing technique may be used to etch back the adhesion/barrier metals and any conductive material deposited on the dielectric layer 28 . Alternatively, a metal layer may be deposited on the interconnect line 26 and then patterned and etched to form the metal plug 32 . Here, the dielectric layer 28 would then be formed over the metal plug 32 .
[0025] The dielectric layer 28 is preferably planarized at this time by chemical-mechanical polishing or etch back to form a planar top surface. The resulting thickness of the dielectric layer 28 should be thick enough after planarization to provide adequate electrical isolation of the interconnect line 26 from a subsequent level of metallization. For example, an approximate thickness of 400 to 600 nm provides suitable isolation.
[0026] Referring now to FIGS. 4 - 6 , after the formation of the metal plug 32 and the dielectric layer 28 , defects d may be exist at the surface of the metal plug 32 . For example, as shown in FIGS. 4 and 6, a seam or recess d may exist at the boundary of the metal plug 32 and the dielectric layer 28 . As illustrated in FIG. 5, a bulge or hump d may be formed at the boundary of the metal plug 32 and the dielectric layer 28 from over polishing of the dielectric layer 28 . These defects such as seams, recesses, bulges or other topographical features would typically cause MOM capacitor reliability and yield problems.
[0027] The lower metal electrode 36 of the capacitor 20 is formed by depositing electrically conductive metal layers 52 - 58 on the dielectric layer 28 and the metal plug 32 , as illustrated in FIG. 7. The lower metal electrode 36 is selectively formed by an appropriate technique, such as chemical vapor deposition (CVD). Other methods of depositing the lower metal electrode 36 may include sputtering, reactive sputter etching (RSE), and plasma enhanced chemical vapor deposition (PECVD). The lower electrode 36 includes multiple metal layers 52 - 58 in stacked relation to each other. Layer 52 acts as a seed layer and is a first metal layer preferably formed of titanium. Layer 54 is a first metal nitride layer and preferably is formed of a refractory metal nitride such as titanium nitride. Layer 56 is a first aluminum layer and layer 58 is a second metal nitride layer also preferably formed of titanium nitride.
[0028] The capacitor dielectric layer 38 is selectively formed over the lower metal electrode 36 using an appropriate technique. The capacitor dielectric layer 38 may be deposited using CVD or any of the other techniques referenced with respect to depositing the lower metal electrode 36 . As shown in FIG. 7, a photoresist layer or mask M 1 is formed and patterned over the capacitor dielectric layer 38 using well known photolithography techniques before an etching step is performed. The first aluminum layer 56 and the second metal nitride layer 58 are used as an etch stop when patterning and etching the capacitor dielectric layer 38 .
[0029] Referring to FIG. 8, the upper metal electrode 40 is then deposited by CVD, for example. Other methods of depositing the upper metal electrode 40 include physical vapor deposition (PVD), sputtering, reactive sputter etching (RSE), and plasma enhanced chemical vapor deposition (PECVD). The upper metal electrode 40 includes multiple metal layers 62 - 66 formed in stacked relation. Layer 62 is a third metal nitride layer and preferably is formed of a refractory metal nitride, such as titanium nitride. Layer 64 is a second aluminum layer and layer 66 is a fourth metal nitride layer also preferably formed of titanium nitride. Here, the second aluminum layer 64 is relatively thinner that the first aluminum layer 56 of the lower metal electrode 36 . The second aluminum layer 64 and the fourth metal nitride layer 66 of the second metal electrode 40 act as an etch stop for a subsequent via etch.
[0030] As shown in FIG. 9, the multilevel metal electrodes 36 and 40 are patterned with a photoresist layer or mask M 2 formed over the stack of metal layers 52 - 58 , 62 - 66 using well known photolithography techniques. The multilevel metal electrodes 36 and 40 are then etched to form the capacitor 20 . The MOM capacitor 20 thus includes the lower and upper electrodes 36 , 40 and the second dielectric layer 38 therebetween, as shown in FIG. 1.
[0031] An advantage of this method is that the stack of metal layers 52 - 58 of the lower metal electrode 36 , will compensate for defects d at the surface of the metal plug 32 . This will increase device yield, reduce MOM capacitor leakage and thus increase the reliability of the MOM capacitor 20 . Additionally, as described, the first aluminum layer 56 and the second metal nitride layer 58 can be used as an etch stop when patterning and etching the capacitor dielectric layer 38 . Furthermore, the second aluminum layer 64 and the fourth metal nitride layer 66 can be used as an etch stop for a subsequent via etch.
[0032] In another embodiment, after the capacitor dielectric layer 38 is deposited as described above with reference to FIG. 7, the stack of metal layers 6266 of the upper metal electrode 40 are deposited over the capacitor dielectric 38 and the lower electrode 36 . The stack of metal layers 62 - 66 of the upper metal electrode 40 are then patterned and etched using the capacitor dielectric layer 38 as an etch stop. Then the capacitor dielectric layer 38 and the stack of metal layers 52 - 58 of the lower metal electrode 36 are patterned and etched. Here, the second aluminum layer 64 may have about the same thickness as the first aluminum layer 56 .
[0033] Many modifications and other embodiments of the invention will come to the mind of one skilled in the art 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 embodiments are intended to be included within the scope of the appended claims. | An integrated circuit capacitor includes a metal plug in a dielectric layer adjacent a substrate. The metal plug has at least one topographical defect in an uppermost surface portion thereof. A lower metal electrode overlies the dielectric layer and the metal plug. The lower metal electrode includes, in stacked relation, a metal layer, a lower metal nitride layer, an aluminum layer, and an upper metal nitride layer. A capacitor dielectric layer overlies the lower metal electrode, and an upper metal electrode overlies the capacitor dielectric layer. An advantage of this structure is that the stack of metal layers of the lower metal electrode, will prevent undesired defects at the surface of the metal plug from adversely effecting device reliability or manufacturing yield. | 7 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to an air cleaner for the removal of pollutants from an air flow with a filter module, the filter module of which comprises at least one permeable filter layer for the accumulation of pollutants on the filter layer.
[0002] WO 2007/028176 A1 describes an air cleaner for cleaning machine exhaust air, the air cleaner of which has a filter module to remove non-air ingredients. Said filter module comprises several filter layers arranged one after another in the air flow to be cleaned. Each of these layers consists of several filter bars which are parallel but distant from each other wherein the mentioned filter bars are alternatingly set in the successively arranged filter layers in transverse position to the flow direction so that the air flow can take a serpentine-shaped way through the filter module. Said filter bars thereby consist of a porous material such as plastic foam, which is dampened by a fluid such as silicone oil so that non-air and/or undesired ingredients can be extracted from the air flow very effectively.
[0003] However, in the course of operation, such machines are susceptible to pollutant accumulations, which can occur very fast and/or after a relatively short time if the machine is used in highly contaminated air. No only microparticles can be accumulated on the air-permeable filter layers, but also bulkier pollutants such as dust fluff or even insects and leaves, which do not pass through the small spaces between the filter bars, especially on the serpentine-shaped way in case of alternatingly arranged filter bars. In addition, the ab- and/or adsorbed microparticles can agglomerate filter cake pieces after some time, which can clog the filter module and/or the filter layer. With increasing layer thickness of the filter cake, there is an improved extraction/accumulation effect but at the same time the negative effect of an increasing flow resistance of the clogging filter layer can be seen. The latter leads to an increasing performance requirement in terms of filter permeability and/or—in case of limited performance of a used air flow generation drive—to a continuous reduction of the volume flow through the filter.
SUMMARY OF THE INVENTION
[0004] Accordingly, the object of the present invention is to create an improved air cleaner of the above mentioned type, which avoids state of the art disadvantages and which advantageously improves the latter.
[0005] A reduced air permeability of the filter module is particularly critical in cases wherein the air flow to be cleaned is the cool air flow of an electronic device since reduced cooling air flow leads to an increased thermal strain of the electronic components of the electronic device which may entail a thermically induced turnoff of the device and, in the worst case, even damage. In order to avoid such thermal overloads, all ventilators for the generation of the cooling air flow and/or the filter modules have so far been significantly overdimensioned, so that, even if the required maintenance intervals are exceeded, a sufficiently strong cooling air flow is still being generated. This, in turn, leads to increased power consumption and also to troublesome excessive exhaust air flow unless expensive closed cooling air circuit with heat exchangers is used.
[0006] The object of the invention will be, above all, to achieve a permanent and sufficient cooling air flow without over-dimensioning of the ventilator while maintaining efficient removal of the air pollutants as well as simple handling and servicing.
[0007] According to the invention, this problem will be solved by an air cleaner according to the description herein. Preferred embodiments of the invention are also the subject of the description herein.
[0008] To solve the mentioned problem, it will be suggested to provide a bypass of the filter module and/or its filter layer for the air flow to be cleaned, in case that not enough air can permeate the major way through the filter layer as soon as the latter will successively be clogged, i.e. an increasing and more dense filter cake will be formed over the course of time. Instead of applying elaborate means to avoid clogging of the filter layer an increased amount of air will automatically flow through the bypass channel in the present case, even if the filter is increasingly clogged. In a filter bypass formed by this process at least a minimum air flow is maintained even if the filter layer is strongly or completely clogged. Hence, cooling is ensured and overload of the ventilator can be prevented. In other words, according to the invention a bypass channel will be provided and developed in such a way that part of the unfiltered air flow can bypass any filter layer. Surprisingly, such a bypass channel will hardly compromise the cleaning effect of the filter module, at least as long as the filter layer has not yet been clogged with pollutants, since in this case the biggest part of the air flow takes the primary way through the filter layer due to a lack of resistance. Only if the filter layer is clogged and if the resistance for the air flow will be increased air will obviously flow through the mentioned bypass channel.
[0009] In order to maintain a high cleaning effect on one hand, and having sufficient air flowing through the filter module even in case of a clogged filter layer on the other hand, in further embodiments of the invention the ratio between the cross-section of the bypass channel and the surface of the filter layer covering the air flow to be cleaned is relatively small and below 0.5. In particular, the flow cross-section area of the bypass channel may be approximately 10% up to 30%, preferably around 15% to 25% of the filter layer area wherein the mentioned filter layer area will not refer to the filter layer area which is efficiently available for the air flow, i.e. the total of the passing slots of the filter area, but rather to the actual filter area in the air flow consisting of the passing slots and the filter material, i.e. the total of the bar cross-section areas and the areas of the passing gaps between the bars as long as each of those will be located within the mentioned air flow in case of a filter layer consisting of filter bars.
[0010] The total of the cross-section area of the bypass channel and of the mentioned filter layer area is thereby equivalent to the cross-section area of the air flow in which the latter flows towards the filter module. Hence, in further embodiment of the invention the abovementioned filter layer area which is transversely situated in the air flow is smaller than the cross-section area of the air flow, i.e. the filter module will, at least with its permeable filter layer, cover only part of the air flow cross-section while the remaining part of the air flow cross-section can bypass the filter layer through the bypass channel in an unfiltered way. In total, the air flow can bypass and/or permeate the filter module either through the bypass cross-section area or through the total of the passing pores or passing gap areas of the filter layer.
[0011] In one advantageous embodiment of the invention the filter module is located adjacent to a ventilator the intake or exhaust air of which forms the cleaning air flow. If the ventilator consists of e.g. rotational rotor blades around a rotating axis the filter module will suitably be located directly in front of or behind of the mentioned rotor blades in an area which is orthogonal to the rotating axis of the rotor blades. The air flow to be cleaned thereby will be emitted from said ventilator, in particular from the rotor blades, assuming that the cross-section area of the induction or exhaust air flow which forms the air flow to be cleaned is approximately equivalent to the circular area covered by the rotor blades. Based on this assumption, further embodiments of the invention will ensure that the total of the cross-section area of the bypass channel and the area of at least one filter area of the mentioned cross-section area of the ventilator, i.e. in case of a given ventilator design, will be equivalent to the circular area covered by the rotor blades. The ratio between the bypass area and the filter layer area will suitably be within the previously mentioned range of size.
[0012] The bypass channel may be formed single-armed, so that the entire bypass cross-section area is formed by only one arm and contiguous. Alternatively, the mentioned bypass channel may also comprise two separate channel branches and/or two separate channels so that the total cross-section area of the filter layer bypass will be divided. In this case, the abovementioned dimensions, based on the total of the cross-section areas of the bypass channel branches, will apply. However, one single major bypass channel is preferred since this mechanism entails the lowest risk of occlusion in the area of the bypass channel.
[0013] In order to maximize filter performance of the filter layer that covers only a part of the air flow, further embodiments of the invention max comprise a valve system on the bypass channel which closes the bypass channel in case of the filter module being clean and not yet clogged so that the entire air is filtered whereas as soon as the filter will successively be clogged said valve system may be opened and/or activated to open the bypass channel in order to ensure a sufficient cooling air flow.
[0014] Accordingly, in alternative further embodiments of the invention such a valve system may also be omitted so that the bypass channel will permanently maintained open. Surprisingly it is known that there is hardly any reduction in terms of the cleaning performance when the bypass channel remains open, at least as long as the filter layer will not yet be increasingly clogged if the cross-section ratios of the bypass channel and the filter layer are designed appropriately. Obviously, the air flow will then pass the filter layer through the major path due to a lack of resistance, so that the cleaning effect will also occur in cases wherein said bypass channel will be open.
[0015] In further embodiments of the invention said bypass channel will be integrated into the filter module and will be formed by a slot in the filter layer wherein “slot” will not refer to any of the air passing holes and/or passing gaps of the filter layer, but to a substantially larger slot through which the unfiltered air can pass and which will not be affected by the abovementioned clogging problem.
[0016] In further embodiments of the invention at least one filter layer may be formed by a variety of elongated preferably bar-shaped filter elements arranged in regular intervals in the area of the filter layer and may constitute the latter. Hereby, several of such filter layers may preferably be arranged adjacent to each other, whereof each will be formed by elongated filter elements respectively wherein the filter elements are preferably arranged in subsequent filter layers in transverse position to the flowing direction so that the air flow which passes through the gap between adjacent filter elements needs to take a serpentine-shaped and/or meandering path and/or similarly wind itself through the various filter layers.
[0017] Said passing gaps between elongated filter elements are thereby much narrower and/or smaller than the bypass channel mentioned above, and this particularly in terms of area and clearance.
[0018] In further embodiments of the invention the bypass channel has a clearance which is formed by the circular shaped diameter and by the length of the narrower side in rectangular shape and which is at least twice, preferably more than three and suitably more than five times larger than the width of each passing gap between two adjacent filter bars. For example, the bypass channel may be formed by removing one or two filter bars from a filter area consisting of such filter bars.
[0019] In further embodiments of the invention the filter module will be established such that at least one filter layer will not be surrounded by a circumferential, closed frame but will rather be provided with at least one open, frameless circumferential section on which the circumferential edge of the filter module will be formed by the filter layer and/or the filter bars, which in turn will build up the filter themselves. This open system of the filter layer facing the side of the circumference enables the air flow to be cleaned in order to freely and laterally circumvent at least this circumferential section of the filter layer if this should be necessary, e.g. during clogging of the filter layer. In contrast to stat of the art filter modules of electronic devices, the filter layer is consequently not enclosed by a pipe-shaped flow channel. The absence of constraining elements such as walls or guiding plates, laterally enclosing the air flow results in a stronger laminar flow, even in the peripheral sections of the filter layer so that more efficient overall cleaning and accumulation of the pollutants on the filter layer is achieved. While the laterally arranged filter elements remain “clean” in conventional filter modules with a pipe-shaped, limited passing channel an accumulation of pollutant particles also occurs on the lateral filter elements in case of laterally open filter elements, which may simply be shown during operation by the fact that also the lateral filter sections become polluted.
[0020] In further embodiments of the invention at least one filter layer may be formed by freely arranged, overhanging and preferably bar-shaped filter elements having at least one unsupported free end. In further embodiments of the invention the mentioned bar-shaped filter elements may be supported by a central filter support so that the filter elements have two free ends. Alternatively, a holder may be provided by a one-sided filter support so that the filter elements have one free end and overhanging along their entire length. With such an arrangement of filter elements with free ends, the abovementioned laminar flow circumvention around the filter elements will partially be achieved wherein the filter elements show a strong cleaning performance. However, in the case that the filter bars are to achieve a higher stability by means of the holder thereof, preferably bar-shaped filter supports may be provided on opposite ends. In this case, however, the longitudinal sides of the filter layer formed by the external filter bars should preferably be designed in an open way.
[0021] In further embodiments of the invention at least one filter layer may be formed by generally straight filter bars that are parallel to each other.
[0022] In further embodiments of the invention also at least one filter layer may be formed by a bent, elongated filter element, wound in a helical, spiral or meandering shape so that adjacent filter element sections with only narrow passing gaps in between will be achieved.
[0023] Basically the filter layer may consist of different materials. The filter layer will preferably form a wet filter which may contain a chemically or physically active fluid to adsorb or absorb air pollutants. Such adsorbing or absorbing filter fluids may, for example, be oils, emulsions or liquids, depending on the type of the pollutants to be removed. Anti-bacterial anti-viral, anti-fungal or fungicidal additives may optionally be added to the fluid. Such fluids and/or fluid mixtures are preferably carried by a carrier material which is dampened by the mentioned fluid. Accordingly preferably bar-shaped and/or elongated filter elements made of porous foam and dampened by the mentioned fluid will be provided.
[0024] Alternatively filter layers may also consist of tissue layers, sandwich structures made of different porous layers such as textile tissues, fine-pored grid structures and similar materials—depending on the air pollutants to be removed.
[0025] The air cleaner according to the invention may further have a mounting frame surrounding the filter module at least in part. The mounting frame will preferably have a slot in which the filter module may be slid in the direction of the air flow, i.e. orthogonal in relation to the filter area. For this purpose the slot will preferably have a cross-section area, which is at least as big as the total of the filter cross-section area and the bypass cross-section area. In particular, the cross-section area of the mounting frame will be at least as large as the cross-section area of the filter module including the bypass section. In this case, the filter module may advantageously be completely slid into the mounting frame.
[0026] Furthermore, the air cleaner advantageously comprises a mounting system which may be connected to the filter module in a detachable manner. Advantageously, this mounting system may be the abovementioned mounting frame. However, other mounting systems are also possible as long as the filter module may be installed in a detachable way. Simple replacement of the filter module is hence possible. The respective connection will suitably be ensured through frictional closure. In this way, the filter module may be easily slid into the slot and attached with a press fit. Advantageously, the filter module may thereby be enclosed in a mounting frame and attached to it with a press fit.
[0027] Furthermore, the air cleaner according to the invention may have an enclosure through which the air flow may flow through the filter module from one input orifice to an output orifice. Ideally, the air flow will thereby be biased through the enclosure on the way from the input orifice to the filter module and/or from the filter module to the output orifice. Advantageously, circumvention by more than 45° or suitably by approx. 90° will thereby occur. The orifice and/or the walls of the enclosure are designed in such a way that the air will be not able to enter or leave the air cleaner orthogonally to the passing area of the filter module but will be circumvented before or after passing through the filter module. Advantageously, the air enters the enclosure parallel to the passing area of the filter module. This may entail a particularly space-saving arrangement which is easy to maintain.
[0028] Alternatively or additionally, a radial ventilator may be used, which may axially absorb the air flow and radially blow it to the outside. The enclosure walls may still circumvent the air flow.
[0029] In further embodiments of the invention, the filter module and/or a ventilator of the air cleaner may be mounted on a carrier element and be movable due to the latter. Thereby, filter module and ventilator are advantageously installed on separate carrier elements and are individually and independently movable by means of those. Hence, simple mounting and/or replacement is ensured.
[0030] Besides the use of the above mentioned bypass the present invention comprises a second aspect which will also be an independent object of the present application.
[0031] The present invention thereby comprises an air cleaner, in particular a cooling air cleaner of an electronic device for the removal of pollutant from an air flow with a filter module having at least one permeable filter layer for accumulation of the pollutants on the filter layer. In accordance with the invention, the second aspect will ensure that the air cleaner is designed as an air cleaning module that is reversibly attached to the input device of a machine housing so that it may be detached from the input device during replacement of the filter module. The design of the air cleaner according to the invention has the advantage of the filter module being substantially easier to replace than in conventional air cleaners which have usually been irreversibly connected to the machine housing, e.g. screwed or riveted to the latter.
[0032] Advantageously, detaching the attachment of the air cleaning module from the machine housing will be done without using any tools. Hence, to replace the filter module, the air cleaning module may be detached without tools and moved into a position wherein the filter module is accessible in an easier way. Another advantage consists in the attachment being possible without tools.
[0033] Advantageously, the air cleaning module comprises at least one mounting element to which the filter module is attached. This mounting element may be, for example, the mounting frame described above. Advantageously, the filter module may hereby be reversibly attached to the mounting frame which may itself be reversibly attached to the machine enclosure.
[0034] Another advantage is the fact that the air cleaning module further comprises a ventilator through which the air flow is moved through the filter module. Advantageously, the ventilator is thereby connected to a power source of the electronic device by means of wires that are sufficiently long to move the air cleaning module in a position in which the filter module is easily accessible for being replaced. Advantageously, the air cleaning module may be completely removed from the machine housing during this process.
[0035] Advantageously, mounting is accomplished by means of a flexible element. This will include the advantage that attachment may easily be detached manually on one hand, and that the air cleaning module may easily be removed and re-attached on the other hand. In addition, by the use of a flexible element, vibrations of the air cleaning module may be absorbed and compensated without any problem. Advantageously, the flexible element is a spiral spring having adjustable length.
[0036] Advantageously the flexible element will thus be attached to the machine housing exerting pressure to air cleaning module on the input device. Advantageously, a flexible element—i.e. a spring spiral—is stretched between two fixing points on the machine housing and thereby exerting pressure to the air cleaning module which is arranged between these two fixing points on the input device. In this way, the air cleaning module may easily be removed by means of pulling the adjustable flexible element to increase its length and hence takeout of the air cleaning module from the input device.
[0037] Advantageously the input device is provided with fixing elements that avoid lateral shifts of the air cleaning module. Advantageously the input device has an air passing orifice through which the air flows from the air cleaning module into a ventilated room.
[0038] An air cleaning module, which may be connected to the input device in a detachable way, is of advantage, irrespective of the use of a bypass, and object of the present invention. In a particularly advantageous design of the present invention, such an air cleaning module will thus be combined with a bypass according to the invention. In particular, the air cleaning module is an air cleaner as described above with regard to the bypass.
[0039] The present invention further comprises an electronic device with an air cleaner as described above. In particular, the electronic device is an entertainment, gambling and/or betting machine. Also, the electronic device has a machine housing wherein the air cleaner is located at or on the inside of the machine enclosure. If the air cleaner is an air cleaning module which is reversibly attached to the machine enclosure the machine housing has a suitable input device which for this purpose is of great advantage. Furthermore, an advantageous flexible element is installed on the machine housing as described above.
BRIEF DESCRIPTION OF THE DRAWINGS
[0040] In the following, the invention will be described in detail by means of preferred embodiment examples and corresponding drawings, wherein:
[0041] FIG. 1 : is a schematic display in perspective of the air flow to be cleaned and of the included filter module which is provided with a filter layer situated transversely alongside the air flow and a bypass channel around the filter layer if the invention is designed in an advantageous way,
[0042] FIG. 2 : is a schematic top view of the filter layer of the filter module from FIG. 1 formed by the filter bars,
[0043] FIG. 3 : is a top view of the ventilator to generate the air flow, which is partially led through the filter layer from FIG. 2 ,
[0044] FIG. 4 : is a top view of the filter module installed directly in front of the ventilator from FIG. 3 , showing the cover of filter layer and rotor blades of the ventilator and the laterally designed bypass channel,
[0045] FIG. 5 : is a lateral view of the filter module and the ventilator connected to it as a schematic representation, showing the limited cover of the filter layer of the filter module and the cooling device which generates the air flow,
[0046] FIG. 6 : is a perspective view of the two-layered filter model of the previous figures.
[0047] FIG. 7 : is a schematic top view of a filter model according to a further embodiment of the invention, in which the bypass channel is located at the center, and in which the filter support holding the filter element has a diagonal position,
[0048] FIG. 8 : is a top view of the ventilator to generate the air flow through the filter module from FIG. 7 ,
[0049] FIG. 9 : is a top view of the filter module from FIG. 7 , showing the cover of filter module and ventilator as well as the covers of the bypass channel, installed on the ventilator from FIG. 8 ,
[0050] FIG. 10 : is a scheme of the filter module after a further embodiment of the invention with helically bent, elongated filter elements which form two consecutive filter systems wherein partial view A shows a top view of the filter module and partial view B a lateral view of the filter module and the permeating air flow, and
[0051] FIG. 11 : is a lateral view of the filter module from FIG. 10 , if it is installed on a ventilator for the generation of the air flow by the filter module wherein the filter module is mounted on the back side of the ventilator which is not facing the rotor blades of the ventilator, and
[0052] FIG. 12 : is a view of a filter module with two filter layers each having straight filter bars wherein the filter bars are fixed with supports on the filter bar end sections; as well as a view of the mounting frame wherein the filter module may be installed, and
[0053] FIG. 13 : is a embodiment example of the second aspect of the present invention wherein the air cleaner is designed as an air cleaning module and reversibly attached to an input device of a machine housing, and
[0054] FIG. 14 : is a perspective of an electronic device enclosure section, concerning a ventilation system for ventilation of the electronic unit, and
[0055] FIG. 15 : is a detailed view of the arrangement shown in FIG. 14 , and
[0056] FIG. 16 : is a further top view of the arrangement shown in FIG. 14 and FIG. 15 , and
[0057] FIG. 17 : is a movable support for a filter module for the ventilation arrangement shown in FIG. 14-15 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0058] In the embodiment shown in FIGS. 2 to 6 , the air cleaner comprises a filter module 1 as well as a ventilator 2 . Ventilator 2 generates an air flow which is cleaned by the mentioned filter module 1 . Advantageously, said air cleaner will be installed on the inside of an enclosure (not shown in details here) of an electronic device such as a gambling machine wherein the mentioned air flow serves for cooling the electronic components of the mentioned machine.
[0059] It may be mentioned that the air cleaner may also be used in a computer (PC) with a big, midi or mini tower enclosure or a desktop enclosure or a server station, an industrial PC, in switchboxes or distributor boxes.
[0060] As shown in FIG. 2 , the filter module 1 may consist of elongated, bar shaped filter element 6 (in the drawn version), which—see FIG. 5 —are arranged consecutively in two spheres so that the filter module 1 has two ( 2 ) filter layers 4 which are located transversely alongside the mentioned air flow 52 . Each of the mentioned filter layers 4 thereby consists of straight, bar-shaped filter elements 6 .
[0061] Those filter elements 6 are generally parallel and adjacent (in a small distance) to each other leaving six narrow passing gaps between adjacent filter elements. An imaginary shell of such a filter layer 4 could be similar to the one of a flat cuboid wherein its thickness is generally formed by the thickness (i.e. the diameter) of the bar-shaped filter elements.
[0062] As shown in FIG. 5 , the filter elements 6 are hereby arranged alternatingly in the filter layers 4 , which are installed consecutively in the direction of the air flow and transversely to the flow direction, especially in such a way that a filter bar of the rear filter layer is installed where the front filter layer has a passing gap 53 and, vice versa, that the front filter layer has a filter bar where the rear filter layer has a transmission gap 53 . This is where the air, flowing through filter module 1 , passes through the filter layers on a serpentine-shaped and/or meandering way.
[0063] The mentioned filter elements 6 may advantageously consist—in the initially mentioned way—of porous foam and be dampened with an appropriate fluid so that the filter layers 4 form a wet filter.
[0064] The mentioned filter elements 6 of the filter layers 4 are hereby advantageously attached to a common filter support 5 , which is located transversely—in the drawn embodiment—roughly in the longitudinal center of the filter elements 6 . Accordingly, the mentioned filter elements 6 have two freely overhanging ends. Hence, each of the filter layers has, in total, 4 open circumferential sides free of guiding plates or pipes limiting the air flow, i.e. the air flow flowing past the edges of each filter layer 4 is not radially limited.
[0065] Ventilator 2 for the creation of air flow may generally be designed in different ways. According to the drawn embodiment, the ventilator 2 may comprise 2 rotor blades 15 that are arranged in a radial position of the drive axis 20 , around which the mentioned rotor blades 15 are rotatorily driven by a ventilator engine 16 .
[0066] As shown in FIGS. 1 and 4 , the filter module 1 and/or its filter layers 4 are not located alongside the entire cross-section of the generated air flow 52 and/or the entire projected cross-section of the ventilator 2 , which is defined by the circulating rotor blades 15 but leaves a bypass channel 50 , through which the air flow 52 may bypass the filter layers 4 freely and without being filtered. The mentioned bypass channel 50 amounts to approx. 15% to 20% of the filter layer surface 54 of the filter layers 4 shown in FIG. 2 .
[0067] The clearance 51 of bypass channel 50 , describing its minimum cross-section width, thereby exceeds the size of the clearance 61 of the passing gap 53 between the filter elements 6 by a multiple, as displayed in FIGS. 1 and 4 .
[0068] As shown in FIG. 5 , the filter module 1 is directly coupled with the ventilator 2 wherein the mentioned filter support 5 may be attached to the ventilator 2 by means of appropriate fixing devices 23 . According to FIG. 5 , the mentioned filter support 5 may also consist of two support bars 9 , each comprising one filter layer 4 and being able to carry a variety of filter elements 6 wherein the mentioned support bars 9 are arranged back-to-back.
[0069] As shown in FIG. 1 , the filter module 1 with its filter layers 4 covers the biggest part of the cross-section area of the air flow 52 so that in case of a fresh and still un-clogged filter, the biggest part of the air flow 52 permeates the filter layers 4 as there is no strong flow resistance. Only a small part of the air flow 52 permeates the mentioned bypass channel 50 .
[0070] If, however, the filter module 1 and/or its filter layers 4 are clogged so that a dynamic pressure arises and/or increases, the air flow 52 practically evades and an increasingly bigger part of it starts permeating the bypass channel 50 . This ensures that there is still a sufficient air flow which may be used as a cooling air flow.
[0071] As shown in FIG. 1 , the filter module 1 with its filter layers 4 advantageously covers approx. 75% to 85% of the cross-section area of the air flow 52 and/or of the cross-section area swept by the ventilator 2 and its rotor blades 15 , whereas the remaining cross-section area of the air flow 52 remains free. Thereby, the filter layers 4 with their external edges do not have to correspond to the presumably circular ventilator and/or the presumably cylindrical air flow, but the filter layers 4 may rather exceed the latter, so that the initially mentioned area proportions describe the proportion between the area of the filter layers 4 covered by the air flow and the cross-section of the bypass channel 50 .
[0072] As shown in FIG. 6 , each filter layer 4 has several open sections on the circumferential side. On one hand, the longitudinal sides, formed by the filter elements 7 and 8 on the external extremes—see FIG. 6 —are open. On the other hand, the front ends of the filter layer 4 , formed by the free ends 6 a and 6 b , are open—see FIG. 6 .
[0073] FIGS. 7 to 9 show an alternative version of the invention wherein the substantial difference to the version shown in FIGS. 1 to 6 consists in the bypass channel 50 being centrally arranged in relation to the filter layers 4 and mostly produced by the fact that at least one bar-shaped filter element 6 has been left aside in a central section of the filter layers 4 , so that a central, elongated slot is formed to provide the bypass channel 50 —see FIG. 7 .
[0074] Furthermore, FIGS. 7 and 9 show that the bar-shaped filter support 5 , to which the filter elements 6 are attached, may also be positioned diagonally so that the outer filter elements are maintained on one end respectively, whereas the filter elements arranged towards the center are kept in their central position and freely overhang on both sides. Apart from that, reference may be made to the description of the aforementioned embodiment.
[0075] FIGS. 10 and 11 show another model, in which the filter module 1 comprises two consecutive filter layers 4 with transversely arranged (with regard to the flow direction), alternating filter elements facing each other, similar to the aforementioned models. The mentioned filter elements 6 are also elongated, bar-shaped objects, which are though not developed as straight bars but as helically bent bars attached to a common central filter support 5 which basically corresponds to the axis of the helical shape of the filter elements 6 . As shown in FIG. 10 , the respective helical filter elements 6 of the to filter layers 4 a and 4 b are alternatingly arranged in such a way that they are facing each other in the flow direction to ensure that the filter element 6 of the rear filter layer 4 a is located where the front filter layer 4 b has its passing gap. The filter element of the front filter layer 4 b in turn will be respectively located where the rear filter layer 4 a has its passing gap.
[0076] As shown in FIG. 10 , however, the filter layers 4 of this model also have a bypass channel 50 through which a part for the air flow 52 may permeate freely, unhampered and without being filtered. The mentioned bypass channel may here, due to a shortcut and/or a slot, form at least one of the filter elements 6 so that a free passing slot develops in the filter layers 4 —see FIG. 10A .
[0077] As shown in FIG. 11 , the filter module 1 may, according to FIG. 10 , be advantageously be attached on the backside of the ventilator engine 16 by means of the mentioned central filter support 5 so that the filter module 1 is transversely situated in the air flow 52 with its filter layers 4 .
[0078] FIG. 12 shows a view of the filter module 1 that has two filter layer spheres 4 a , 4 b , each being provided with a number of straight filter bars 6 wherein the filter bars 6 are attached and positioned in a freely carrying manner on the filter bar end sections 6 a , 6 b , by means of carrier elements. Furthermore, FIG. 12 shows a view of a mounting frame 26 in which the filter module 1 may be installed. In the present case, the mounting frame 26 is rectangular and closed in an annular way with the four arms 31 a , 31 b , 31 c and 31 d . It also comprises an insertion slot 27 which surrounds the filter module 1 towards the air flow 52 and/or orthogonally in relation to the area that is defined by the filter layer sphere 4 . This ensures that the filter module 1 may be inserted into the mounting frame 26 and/or removed from it in a simple way.
[0079] The size and/or the dimensions of the insertion slot 27 is preferably adapted to the size and/or to the dimensions of the filter module 1 in such a way that the filter module 1 is kept press-fitted in the insertion slot 27 . In particular, the width of the insertion slot 27 is equivalent to the length of the filter module in the direction of the longitudinal center line of the straight filter bars. Consequently, the filter bars may be used as pressure elements that ensure the necessary friction at the ends of the filter bars in order to ensure fixation of the filter module 1 in the mounting frame 26 .
[0080] Alternatively or in combination, at least one of the support elements 9 could develop an appropriate press fit with its front side and the respective frame arms of the mounting frame 26 .
[0081] The mounting frame 26 is used for the indirect installation of the filter module 1 on any appropriate mounting element, for example on an enclosure of the aforementioned ventilator 2 .
[0082] FIG. 13 shows a design example of an air cleaner in which the second aspect of the present invention has been implemented. The air cleaner is hence an air cleaning module which is reversibly attached to the input device of a machine housing 80 . The input device is thereby located behind the air cleaning module in FIG. 13 , so that it may not be identified in the drawing. Advantageously, the input device has an air passing orifice with is connected to the air cleaning module and by means of which air may flow through the air cleaning module into a ventilation area.
[0083] The air cleaning module thereby has, once again, a mounting frame 26 , into which the filter module may be inserted. To replace the filter module, the entire air cleaning module may now be removed from the input device. The reversible attachment is therefore done by means of a spiral spring 60 , which is extended between two fixing points 61 and 62 on the machine enclosure. In addition, the air cleaning module is provided between the two fixing areas 61 and 62 , so that the spiral spring 60 presses the air cleaning module against the input device of the machine enclosure. The spiral spring 60 is thereby located approximately in the middle alongside the air cleaning module. In this way, the air cleaning module may easily be detached prior to input and subsequently pulled out laterally below the spiral spring.
[0084] The mounting frame 26 is thereby installed at the input device of the machine housing in such a way that the filter sphere is parallel to the wall of the enclosure on which the input for the air cleaning module is located. The spiral spring 60 thereby presses the two side bars of the mounting frame onto the enclosure.
[0085] The air cleaning module further has a ventilator that forms a component with the mounting frame. By means of the latter, the entire air cleaning module with mounting frame, filter module and ventilator may be extracted to replace the filter module. Thereby, the ventilator is connected to a power source by means of electrical wires 70 . These electrical wires 70 are long enough to enable a complete extraction of the air cleaning module from the enclosure.
[0086] The air cleaning module shown in FIG. 13 may be operated with any filter module, also with those having no bypass area. In the design example shown in FIG. 13 , the air cleaning module is though combined with a filter module that is provided with a bypass area 50 .
[0087] In this, the filter module with its general structure is equivalent to the filter module shown in FIG. 12 wherein filter elements 6 are located between two support bars 9 which serve as filter bar supports. The support bars 9 are thereby inserted into the mounting frame 26 and attached to the latter by means of a press fit.
[0088] Also, the filter module has two bypass areas 50 . The support bars 9 are therefore provided with end sections in which no filter elements will be provided. Such a filter module may of course be also used independently of the air cleaning module shown in FIG. 13 .
[0089] FIG. 14 shows a perspective of an enclosure 141 section of an electronic gambling machine, i.e. the one according to a ventilation system 142 for the ventilation of the electronic unit of the gambling machine. In the present case, the gambling machine is a “slot machine”. The electronic unit consists in this case of a processor board and may be installed in the enclosure in the appropriate electronic section 143 wherein the electronic range is encapsulated in itself and has at least one air input orifice 144 as well as at least one air exhaust orifice 145 . The ventilation system 142 generally comprises a ventilator 146 , a filter module 1 as well as an air flow channel. The ventilation system 142 is directly coupled with the air input orifice 144 . Both the filter module 1 as well as the ventilator 146 are installed on separate carrier elements and designed as movable devices by means of the latter in order to ensure easy installation and/or replaceability.
[0090] As further shown in FIG. 15 , the ventilator 146 is a radial ventilator in the present case, i.e. the air is axially aspirated, rotated by 90°, blown out radially, i.e. orthogonally to the aspiration direction, and reaches the electronic section 143 via an alteration channel 147 through the air input orifice 144 and, in a subsequent step, leaves the electronic section 143 through the air exhaust orifice 145 .
[0091] FIG. 17 shows a carrier element 170 on which the filter module 1 may be installed. The carrier element 170 further has a handle system 171 for easier handling during shifting as well as a fixation section 172 for the attachment of the carrier element 170 in a final position within the ventilation system 142 . | The present invention relates to an air cleaner for the removal of pollutants from an air flow by a filter module, the filter module of which comprises at least one permeable filter layer for the accumulation of pollutants on the filter layer. According to the invention, a bypass channel will be provided and established such that part of the unfiltered air flow may bypass any filter layer. Surprisingly, such a bypass channel does hardly compromise the cleaning effect of the filter module, at least as long as the filter layer has not yet been clogged with pollutants since in this case the biggest part of the air flow will take the major path through the filter layer due to lack of resistance. Only if the filter layer is clogged and if resistance for the air flow increases, air will obviously flow through the mentioned bypass channel. | 1 |
BACKGROUND OF THE INVENTION
The invention relates to information retrieval machines and more particularly to machines for magnetically reading and writing information on a magnetic tape.
Machines for magnetically acting on the tape held in individual cartridges or cassettes which are held by and are selectively moved out of a rotating carousel have previously been proposed. The tape used in such machines is of the relatively narrow variety, and the tape is held in the carousel with the axes of the tape spools in the cassette extending at angles to the axis of the carousel. Such machines are, for example, disclosed in the U.S. Pat. to Foelkel No. 3,617,066 and the U.S. Pat. to Raine No. 3,484,055. A similar mechanism for bringing any one of a series of motion picture film cassettes to a position wherein the film of the cassette passes through an operative position is disclosed in Kremp et al. U.S. Pat. No. 3,702,727.
Summary of the Invention
It is an object of the present invention to provide an improved machine for magnetically writing and reading information on a magnetic tape which is particularly suitable for use with relatively wide magnetic tapes such as tapes, for example, having a greater width than 21/2 inches. In this connection, it is an object of the invention to provide a carousel for receiving such tapes rolled on a spool of a tape catridge, with the spool and rolled up tapes having their axes extending parallel with the axis of rotation of the carousel, and mechanism for ejecting the cartridges from the carousel for a subsequent reading and writing action and for pulling the cartridges back into the carousel after the reading and writing actions are complete.
In a preferred embodiment, the machine of the invention comprises a pair of opposite spindles for receiving such a carousel and allowing it to rotate, a plurality of tape cartridges received in cavities in the carousel, a plunger moveable into each of the cavities as the cavity is positioned in alignment with the plunger for making a mechanical connection with the cartridge and moving the cartridge axially out of the carousel onto a drive shaft, mechanism for driving the latter shaft for partially unrolling the tape and moving its leading end onto a tape carrying bed, a read/write disk having read and write transducers in substantial alignment with the surface of the bed carrying the tape, a takeup roll for receiving the leading end of the tape, a rotatable arm for cinching the tape onto the takeup roll, motor means for driving the takeup roll and means including a nipped mandrel and pressure roll and motor means for driving the mandrel for moving the tape at a controlled speed off of the cartridge and onto the takeup spool during which time the read/write head may be effective in writing information on or reading information from the tape.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a magnetic tape cartridge useable in the tape cartridge loading machine of the invention and which includes a central spool on which magnetic tape is wound;
FIG. 2 is a sectional view taken on line 2--2 of FIG. 1 showing just the spool of the cartridge;
FIG. 3 is an end view of the spool shown in FIG. 2;
FIG. 4 is an end elevation view of a cartridge receiving cassette or carousel useable in the machine;
FIG. 5 is a plan view of the tape cartridge loading machine of the invention;
FIG. 6 is a fragmentary sectional view of the machine taken on a horizontal section plane with the carousel shown in FIG. 4 being positioned on the machine;
FIG. 7 is a side elevational view of the machine taken from line 7--7 of FIG. 5;
FIG. 8 is an end elevational view of the machine taken from line 8--8 of FIG. 5;
FIG. 9 is an end elevational view of the machine taken from line 9--9 of FIG. 5;
FIG. 10 is a sectional view on an enlarged scale taken on line 10--10 of FIG. 6 and with the carousel being removed from the machine;
FIG. 11 is a sectional view on an enlarged scale taken on line 11--11 of FIG. 6;
FIG. 12 is a sectional view on an enlarged scale taken on line 12--12 of FIG. 6;
FIG. 13 is a sectional view taken on line 13--13 of FIG. 5; and
FIG. 14 is a sectional view taken on line 14--14 of FIG. 13.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The tape cartridge loading machine of the invention utilizes a plurality of tape cartridges 30 as illustrated in FIGS. 1, 2 and 3. A tape cartridge 30 comprises a spool 32 and a length of magnetic tape 34 wound on the spool 32. The tape 34 has a relatively narrow end 34a.
The spool 32 is generally cylindrical and has a flange 36 on one end and an insert 38 within it at its other end. The end flange 36 has a central opening 40 through it, and relatively pointed teeth 42 are provided within the opening 40. The flange 36 is provided with an outwardly flaring portion 36a on its external periphery.
The insert 38 is formed with an inwardly extending rib 44 and is slitted on its end to have a series of teeth 46. The teeth 46 have tapered ends 46a and are undercut so as to provide radially extending surfaces 46b.
Six of the cartridges 30 are received and held by a cassette 48 in the form of a carousel. The carousel 48 is provided with six cavities 50 therein each of which has an outwardly flaring surface 50a on its open end. A cartridge 30 is normally disposed in each of the cavities 50 with the outwardly flaring surfaces 36a on the cartridge 30 in contact with the outwardly flaring surface 50a (see FIG. 6) of the cassette. The carousel 48 is provided with two tapered walled recesses 52 and 54 on the axis of rotation of the cassette and has on one end an axially extending flange 56 with an interruption or slot 56a (see FIG. 4) therein. Notches 58 are provided in the exterior surface of the cassette 48, and there is a notch 58 for each of the cavities 50.
Each of the cavities 50 is defined on its bottom by means of a return bent portion 60 (see FIG. 6), and a radially extending flange 62 is formed on the return bent portion 60. A washer 64 of soft yieldable material is disposed and fixed on the return bent portion 60 of each of the cavities 50.
The tape cartridge loading machine 66 for using the carousel 48 loaded with cartridges 30 is provided with a cavity 68 for receiving the loaded cassette 48 (see FIG. 5). A tapered key 72 is provided in the cavity 68, and the cassette 48 is moved into the cavity 68 with the key 72 moving through the slot 56a of the flange 56 on the cassette 48 so that the cassette 48 can be positioned in only one position within the cavity 68. The end 74 of the key 72 overlies the flange 56 in rotary positions of the cassette 48 other than that in which it is inserted into the cavity 68.
The machine 66 carries a pair of opposite tapered plungers 76 and 78, and springs 80 and 82 are provided to act on the plungers 76 and 78. The plungers 76 and 78 fit within the recesses 52 and 54 in the cassette 48 and hold the cassette 48 in proper position within the cavity 68. The machine carries a switch 84 positioned to be actuated by the plunger 78 for indicating when the cassette 48 is in proper position within the machine cavity 68.
A rounded locking member 86 (see FIGS. 6 and 10) is moveable into any of the notches 58. The locking member 86 is an integral part of a lever 88 that pivots about a shaft 90. A switch 92 is positioned opposite the locking member 86 and has an actuating arm 94 that extends into a notch provided in the end of the arm 88. The switch 92 has a built-in spring moving the actuating arm 94 counterclockwise as seen in FIG. 10, and this has the effect of moving the locking member 86 into one of the notches 58. The locking member 86 is moved out of the notch 58 due to the rounded cross section of the notch 58 when the cassette 48 is rotatably driven.
The arm 88 is acted on by a lever 96 which is also swingably mounted on the shaft 90. The lever 96 is acted on by a spring 98 and also by an electromagnet 100. The lever 96 carries a driver roller 102 on its end which is adapted to swing through an opening into driving engagement with an outer peripheral surface of the cassette 48 when the electromagnet 100 is energized. The roller 102 is rotatably driven as will be subsequently described.
A plunger 104 is slideably disposed in the machine 66 and carries a latch 106 by means of a stud 108 fixed to the plunger 104 (see FIG. 6). The latch 106 is rotatably disposed on the stud 108 by means of a bearing 110 of the ball type. Belleville spring washers 112 hold the bearing 110 against a retaining washer 114 that is fixed on the end of the stud 108. The latch 106 is serrated longitudinally to have a plurality of fingers 116 each of which is somewhat pointed as shown in FIG. 6 and has a retaining surface 116a for purposes to be hereinafter described.
The plunger 104 has a pair of notches 118 and 120 in its periphery adapted to receive a plunger 122. A switch 124 is actuated by the plunger 122.
The plunger 104 is driven from an electric motor 126 mounted on the machine (see FIGS. 5 and 11). The motor 126 drives a worm gear 128 which is in mesh with a gear 130. The gear 130 is fixed on a shaft 132, and a second gear 134 is also fixed on the shaft 132 so that there is a driving connection from the gear 130 to the gear 134. A gear rack 136 is provided in the plunger 104, and gear 134 is in mesh with the rack 136.
A cartridge receiving shaft 138 is rotatably disposed in the machine by means of bearings 140, and the shaft 138 is provided with longitudinal splines 142. The splines 142 are so spaced that they may pass between the teeth 42 in a cartridge 30. An annular flange 144 is carried by the shaft 138, and a rubber washer 146 is positioned between the flange 36 of a cartridge 30 and the flange 144 is registering depressions provided in the flanges 36 and 144.
The shaft 138 is driven from a motor 148 (see FIG. 9). A gear 150 is mounted on the shaft 138 through a one-way bearing 152 and a sleeve 154. The gear 150 has a ribbed peripheral surface 150a, and an internally toothed belt 156 extends over the ribbed portion 150a and over a correspondingly ribbed output pulley 158 of the motor 148. The sleeve 154 is fixed with respect to the shaft 138, and the one-way bearing 152 is of such construction that when the gear 150 is driven from the motor 148, the shaft 138 is correspondingly driven.
A one-way bearing 160, which is of an opposite hand with respect to that of the bearing 152, is disposed on the shaft 138 and within an annular member 162. An annular pad 164 is disposed between the member 162 and a surface 166 of the machine for braking the shaft 138 at times as will be hereinafter mentioned.
A gear 168 (see FIGS. 8 and 9) is driven from the gear 150 through a gear train including a gear 170 in mesh with the two gears 168 and 170. The gear 168 drives the roller 102 through a flexible shaft 174.
A peeler bar 176 (see FIGS. 5 and 13) for peeling the tapered end 34a of the magnetic tape 34 from the surface of a cartridge 30 is swingably mounted on a pivot shaft 178. The bar 176 has a relatively sharp tip 176a for tape peeling purposes, and a plurality of rolls 180 are carried by and are rotatably disposed within the bar 176. An electromagnet 182 is provided for swinging the bar 176 and has an armature 184 swingably disposed on the shaft 178. A rotary driving connection is provided between the armature 184 and bar 176 including a U-shaped spring 186 which is disposed in registering cavities provided in the armature 184 and bar 176. The rolls 180 are driven from the gear 170 by means of a flexible drive shaft 188 (see FIG. 6).
The machine is provided with a flat table 190 (see FIGS. 13 and 14) across which the tape 34 travels from the rolls 180, and a rotary magnetic read/write disk 192 is coextensive with the upper surface of the table 190. The read/write disk 192 is drivingly rotated from any suitable drive means (not shown) and has a pair of magnetic write heads 194 and a pair of magnetic read heads 196 spaced at 90° adjacent the outer edge of the disk 192.
A magnetic tape shield 198 extends from an end of the table 190 and overlies the table and has a rounded portion 198a extending downwardly into a circular cavity provided in the upper surface of the disk 192. A plate-like tape guide member 200 overlies and is spaced from the table 190, and an arcuate arm 202 is swingably disposed on the upper surface of the guide member 200 by means of a shaft 204 carrying the arm 202 (see FIGS. 7, 13 and 14). An arcuate opening 202a is provided in the member 200 through which the arm 202 pivots for acting on magnetic tape passing along the table 190 and over the shield 198 as will be hereinafter more fully described. An arm 206 is fixed on the shaft 204, and an electromagnet 208 actuates the arcuate arm 202 through the arm 206 and shaft 204. A spring 209 acts against the electromagnet 38 and swings the arm 202 downwardly.
A tape takeup spool 210 is rotatably disposed within shells 212 and 214 at the end of the table 190. The spool 210 is provided with a rubber covering 210a. A motor 216 (see FIG. 14) is provided for driving the spool 210 and is coupled with the spool 210 by means of a magnetic clutch 218. A pressure pad arm 220 (see FIG. 13) is pivoted on a shaft 222 in order to move toward the spool 210, and an electromagnet 224 is provided for swinging the arm 220 about the shaft 222.
A mandrel or capstan 226 is disposed at the end of the table 190 and is driven from a motor 228 (see FIG. 7). The motor 228 is drivingly coupled with the mandrel 226 by means of a worm gear 230 on the output shaft of the motor 228 in mesh with a gear 232 having a direct drive connection with the mandrel 226. Pressure rolls 234 (see FIGS. 13 and 14) carried by a swing arm 236 are disposed at the side of the mandrel 226, and an electromagnet 238 is provided for actuating the arm 236 and moving the rolls 234 to have a nip with the mandrel 226. The shells 212 and 214 have a tape entrance slot 240 between them through which the tape moves from the table 190 onto the spool 210, and spring fingers 242 are carried by the guide member 200 and extend between the rolls 234 for guiding the magnetic tape into the shells 212 and 214 and into the vicinity of the spool 210.
In operation, six of the cartridges 30 each including a spool 32 and a length of magnetic tape 34 wound on the spool, are loaded into the carousel 48. A cartridge 30 is placed in each of the cavities 50 with the teeth 46 on the end of the cartridge 30 passing through and being compressed together due to the tapered tooth ends 46a by the radially extending flange 62 of the cavity 50. The insert 38 is of relatively flexible material to allow flexing of the teeth 46 inwardly as they are moved through the flange 62. When the cartridge 30 is completely within the cavity 50, the outwardly flaring portion 36a on the spool 32 engages with the outwardly flaring surface 50a of the cavity, and the radially extending surfaces 46b engage with the surface 60a of the portion 60 to hold the cartridge 30 within the cavity 50, the teeth 46 having again sprung outwardly due to the inherent resilience of the insert 38.
The carousel 48 is then mounted in the machine so that the plungers 76 and 78 snap into and engage with the tapered sides of the recesses 52 and 54 in the ends of the carousel 48. The carousel 48 can be moved into this engagement with the plungers 76 and 78 only in one rotative position which is determined by the slot 56a through which the key 72 passes as the carousel 48 is moved to engage with the plungers 76 and 78. Thus, a particular cavity 50 and the particular cartridge 30 within that cavity are initially in alignment with the plunger 104 and shaft 138. When the carousel 48 is thus moved into position in the machine, the plungers 76 and 78 move outwardly against their springs 80 and 82 to permit this insertion of the carousel into the machine; and, when the carousel 48 is in its proper position in the machine as illustrated in FIG. 6, the plungers 76 and 78 are still slightly out of their at-rest positions. The plunger 78 in this displaced position actuates the switch 84 which may be used to control any associated electronics for in turn controlling the various motors of the machine.
The carousel 48 is then drivingly rotated about the plungers 76 and 78 acting as axles to bring the desired cavity 50 and the desired cartridge 30 into alignment with the plunger 104 and shaft 138. This rotation of the carousel 48 is by the action of the roller 102. The motor 148 is in operation at the time, and it drives the roller 102 by means of the pulley 158, the belt 156, the gears 150, 170, and 168, and the flexible shaft 174. The roller 102 is moved into engagement with the carousel 48 by energizing the electromagnet 100 which rotates the lever 96 and the roller 102 in the counterclockwise direction as seen in FIG. 10 about the shaft 90 against the action of the spring 98. The carousel 48, in its initial position in the machine has the locking member 86 extending into one of the notches 58, and the rotation of the carousel 48 under the action of the roller 102 moves the locking member 86 to the left as seen in FIG. 10 out of the notch 58 against the action of the spring within the switch 92 which functions to normally hold the actuating arm 94 of the switch in its FIG. 10 position. The electromagnet 100 is maintained in energized condition until just prior to an alignment of the desired cavity 50 and desired cartridge 30 with the plunger 104 and shaft 138; and, at this time, the electromagnet 100 is de-energized. The spring 98 moves the roller 102 back to retracted position out of driving engagement with the carousel 48, and the locking member 86 moves into the notch 58 that corresponds with the desired cavity 50 and cartridge 30 to hold the carousel 48 locked in its desired rotative position with the desired cavity 50 and desired cartridge 30 being in alignment with the plunger 104 and shaft 138.
The cartridge 30 in this cavity 50 is then moved by the plunger 104 to interengage with the shaft 138. The shaft 138 is at this time rotating in the so-called reverse direction A (see FIGS. 10 and 13), being driven by the gear 150 through the one-way engaging device 152 and the collar 154. The plunger 104 initially is in its position in which the plunger 122 is within the notch 118, and the plunger 104 is moved to the left as seen in FIG. 6 under the action of the motor 126 driving through the gears 128, 130 and 134 and the rack 136. The latch 106 moves along with the plunger 104, and its fingers 116 move through the flange 62 and into the insert 38 of the spool 32 of the cartridge 30 which is alignment with the plunger 104 and shaft 138. The fingers 116 contact the rib 44 in the spool 32 and are moved inwardly by the rib 44 on continued movement of the latch 106 and fingers 116 along with the plunger 104, and the fingers 116 move behind the rib 44 (to the left of the rib 44 as seen in FIG. 6), with the finger surfaces 116a clamping around the rib 44. The fingers 116 are of flexible material to permit them to so move within and through the internal rib 44 of the cartridge 30. At about this time, the flaring surface 106a of the latch 106 contacts the tapered surfaces 46a of the teeth 46 and cam the teeth 46 inwardly so that, with continued movement of the plunger 104 to the left as seen in FIG. 6, the cartridge 30 is unlatched with respect to the return bent portion 60 of the carousel 48. On continued movement of the plunger 104, the cartridge 30 is moved along with the plunger 104 until finally the cartridge 30 is in its illustrated position in FIG. 6 with the flange 36 of the cartridge 30 in contact with the flange 144 fixed to the shaft 138. As the teeth 42 move to the position of the splines 142 on the shaft 138, the teeth 42 interengage with the splines 142; and the cartridge 30 then begins rotation in the reverse direction A along with the shaft 138. This is in a direction so that any contact of the end 34a of the tape 34 with the surrounding structure tends to wind the magnetic tape 34 more tightly onto the spool 32 of the cartridge 30. The plunger 104 has moved to the left to the position as seen in FIG. 6 in which the plunger 122 has entered the notch 120 in the plunger 104, so that the switch 124 is actuated. The motor 148 is stopped at this time, preferably under the action of the switch 124.
It will be noted that the latch 106 is in firm engagement with the right end of the cartridge 30 when the cartridge 30 is fully seated on the shaft 138, and the shaft 138 holds the fingers 116 in their FIG. 6 positions in which they clamp around the internal rib 44 of the spool 32. At this time, the bearing 110 functions to support the right end of the cartridge 30 as seen in FIG. 6 during its rotation by the shaft 138. The springs 112 compress to hold the cartridge 30 in its position fully seated on shaft 130 with the flange 146 in contact with the flange 144.
At this time, the electromagnet 182 is energized to move the peeler bar 176 in the counterclockwise direction (see FIG. 13) to bring its sharpened tip 176 in close proximity with the exterior surface of the magnetic tape 34 on the spool 32 of the cartridge 30 and to bring the rolls 180 into engagement with the tape 34 on the spool 32. Also, at this time, the motor 148 is again energized but this time to drive in the opposite direction from its original direction of drive. The rolls 180 are driven from the motor 148 through the pulley 158, the gears 150, 170, 172 and 168, and the flexible shaft 188 (see FIG. 6); and the rolls drive the tape 34 as wound on the spool 32 in the forward direction B as seen in FIG. 13. The peeler bar 176 and particularly its sharpened end 176a, with this rotation of the cartridge 30, catches end end 34a of the tape 34 so that it moves across the bed 190 toward the mandrel 226 and takeup spool 210. The tape moves over the magnetic read/write disk 192 and the tape shield 198 and beneath the tape guide member 200. The arm 202 at this time is raised to provide no impedance to the movement of the tape.
The pressure rolls 234 at this time are raised with respect to the mandrel 226, and the forward end 34a of the tape 34 passes beneath the spring fingers 242 and through the slot 240 into a position within the shells 212 and 214 beneath the spool 210 and above the pressure pad arm 220. The spool 210 is driven in direction C (see FIG. 13) from the motor 216 through the magnetic clutch 218, and the electromagnet 224 is energized to rotate the arm 220 in the clockwise direction as seen in FIG. 13 about its pivot shaft 222. The arm 220 pinches the tape 34 between the rubber covering 210a of the spool 210 and the arm 220; and, due to the frictional difference between the rubber covering 210a of the spool 210 and the arm 220 and due to the fact that the curvature of the arm 220 closely matches the exterior curvature of the spool 210, the magnetic tape 34 cinches tightly around the spool 210 and is thus wound on the spool 210 as the motor 216 drives the spool 210 through the magnetic clutch 218. At this time, the electromagnet 224 is de-energized so that the arm 220 retracts to its position as shown in FIG. 13. The electromagnet 182 also is de-energized at this time so as to cause a retraction of the rolls 180 from the surface of the magnetic tape 34 on the spool 32, and the motor 148 may also be rendered inoperative at this time. The speed of the spool 210 as driven by the motor 216 through the magnetic clutch 218 may be such as to provide a relatively high slew speed to the tape 34 as it is being wound onto the spool 210, such as, for example, of 40 inches per second tape speed.
When the desired position in the tape 34 is reached, with the tape travelling at the relatively high slew speed, the electromagnet 238 is energized so as to move the pressure rolls 234 to have a pressure nip with the mandrel 226. The mandrel 226 is driven in direction D by the motor 228 through the gears 230 and 232 to move the tape 34 across the bed 190 toward the spool 210, and the speed of the mandrel 226 is such that the tape 234 is driven at a relatively slow processing speed, such as 1.2 inches per second. The electromagnet 208 is energized at this time, and it moves the arm 202 downwardly so as to hold the tape 34 in close proximity to the heads 194 and 196. The heads 194 and 196 may then be effective to either write information on the tape 34 magnetically or to read such information magnetically from the tape. The motor 216 is still effective to drive the takeup spool 210; however, the magnetic clutch 218 slips so that the peripheral speed of the spool 210 is the relatively low tape processing speed. The one-way bearing 160, the annular member 162 and the annular pad 164 disposed between the member 162 and the surface 166 of the machine operate as a friction brake for braking the shaft 138 and the tape spool 32 to prevent overrun of the spool 32 when the speed of the tape 30 in traversing the bed 190 is suddenly decreased from slew speed to processing speed.
When the magnetic reading and writing action has ceased, the motor 216 and the electromagnet 238 are de-energized and the motor 148 is energized to drive in its original, reverse direction. The shaft 138 and the cartridge spool 32 are then driven in the reverse direction A by means of the pulley 158, the gear 150, the one-way bearing 152 and the sleeve 154; and the magnetic tape 34 is drawn off of the spool 210 and is rewound on the cartridge spool 32.
After the tape 34 has been completely rewound onto the cartridge spool 32, the plunger 104 is moved to the right as seen in FIG. 6 to return the cartridge 30 into its cavity 50 within the carousel 48. This movement of the plunger 104 is due to the driving action of the motor 126, utilizing the gears 128, 130 and 134, and the rack 136. The fingers 116 extend around the internal rib 44 in the insert 38 of the cartridge 30, and the finger surfaces 116a contact the rib 44 and are held from moving out of contact with the rib by means of the end of the shaft 138 within the fingers 116; and, when the plunger 104 moves to the right as seen in FIG. 6, the plunger 104 draws the cartridge 30 off of the shaft 138. Eventually, the fingers 116 draw the cartridge 30 to the right as seen in FIG. 6 through such a distance that the teeth 46 pass through the flange 62. The teeth 46 bend inwardly to allow such passage, and then the teeth snap outwardly so that the tooth surfaces 46b again extend around the flange 62 and into contact with the surfaces 60a to again fasten the cartridge 30 within its cavity 50 of the carousel 48. The plunger 104 continues its movement until the fingers 116 are out of alignment with any of the parts of the carousel 48 and cartridge 30, and at this time the plunger 104 is in such position that the plunger 122 enters the notch 118 of the plunger 104. The switch 124 is again actuated so as to signal to any associated electronics that the carousel may again be rotated to bring another desired cartridge 30 into alignment with the plunger 104 and shaft 138 for processing of this particular cartridge 30.
When it is desired to remove the carousel 48 from the machine, it must be moved back into its original rotative disposition in which it was originally inserted into the machine so that the edges of the slot 56a travel around the key 72. The flange 74 overlying the flange 56 of the carousel 48 in other rotary positions of the carousel prevent the carousel 48 from being removed from the machine in other rotative dispositions. It is therefore easy to retain a count of the particular cartridge 30 that is in alignment with the plunger 104 and shaft 138 in processing position.
Advantageously, the machine utilizing the carousel 48 may be used as a magnetic tape digital recorder, more particularly as a library storage device. Each of the cartridges 30 may have a large data capacity, such as of 35 megabytes to that the total capacity of the machine using six cartridges 30 may be 210 megabytes. The tape 34 may, for example, be 2.7 inches wide and may have a useable length of 660 inches. Advantageously, any one of the six cartridges 30 can be program selected and may be automatically loaded and threaded as above described with the oxide side of the tape 34 in contact with the bed 190. The carousel 48 can be inserted into the machine in only one direction due to the action of the key 72, identifying a rotational home position and enabling cartridge selection under program control. Substitute carousels 48 can obviously be used in lieu of the illustrated carousel 48, and the carousel 48 can be designed with more than six of the cavities 50 to take more than six cartridges 30. Advantageously, the carousel 48 serves as a dust and contaminants protector for the tape 34.
The described machine advantageously provides both automatic loading and threading of the magnetic tape 34, and the machine advantageously ejects a cartridge from the carousel 48 and injects it into a threading chamber in which it is shown in FIG. 6. The arc shaped arm 202 controls the height of the tape 34 to attain the proper head to tape contact for magnetic writing and reading. The motor 228 is preferably of a variable speed hysteresis synchronous type and drives through the worm gear 230-spur gear 232 reduction to provide a smooth velocity to the tape 34 during reading and writing actions on the tape. | A machine for writing information on and reading information from a relatively wide magnetic tape including a carousel for receiving a plurality of cartridges holding such tape with the cartridges being disposed with their axes parallel with the axis of rotation of the carousel, a plunger for latching onto a cartridge in the carousel and moving the cartridge out of the carousel into a tape unwinding position, motor mechanism for unwinding the tape in this position and moving it across a bed carrying a rotatable magneitc read/write disk substantially coextensive with the face of the bed on which the tape travels, a takeup spool for receiving the tape passing across the bed and including a swingable arm for causing the tape to start winding on the spool, and a relatively slowly moving mandrel and a pressure roll cooperating with the mandrel for subsequently moving the tape across the bed so that the disk may have a magnetic reading or writing action with respect to the tape. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a combustion control apparatus for a spark ignition type 2-cycle internal combustion engine. Fresh air mixed with fuel mixed with fuel in a combustion chamber can be self-ignited at an ignition timing preferable for the operation of the internal combustion engine at least in a low load operation region to effect active thermal atmosphere combustion. When it is required to stop the internal combustion engine, the combustion control apparatus stops the internal combustion engine quickly. In addition, the combustion control apparatus provides increased starting performance for the internal combustion engine.
2. Description of Background Art
In a spark ignition type 2-cycle internal combustion engine, an exhaust port and a scavenging port opened or closed by a piston are formed on an inner peripheral face of a cylinder bore. Fresh air mixed with fuel prepressurized in a crank chamber is supplied from the scavenging port into a cylinder chamber while combustion gas in the cylinder chamber is exhausted from the exhaust port. The fresh air mixed with fuel compressed in the cylinder chamber is ignited by an ignition plug.
In such a conventional spark ignition type 2-cycle internal combustion engine, if the exhaust port is increased in size to set the output power and the efficiency in a high speed, high load operation region to values higher than high levels, then, in a low load operation region, the amount of unburned hydrocarbons in the exhaust gas is increased by blow-by of fresh air mixed with fuel or unstable combustion. In addition, the fuel consumption is increased.
In order to eliminate this, the present inventors have developed an internal combustion engine including an exhaust control valve which serves as exhaust path opening adjustment means. The exhaust control valve is driven to an exhaust path opening corresponding to an internal combustion engine speed and a throttle valve opening. Therefore, at least in a low load operation region, when an exhaust port is closed by a piston, the cylinder pressure is controlled appropriately to ignite fresh air mixed with fuel in the combustion chamber with the thermal energy of the combustion gas remaining in the combustion chamber. Therefore, the fresh air mixed with fuel in the combustion chamber is self-ignited at an ignition timing preferable for operation of the internal combustion engine. See, Japanese Patent Laid-Open Application No. Heisei 7-71279.
When ignition timing suitable for operation of an internal combustion engine is controlled positively so that active thermal atmosphere combustion occurs, the combustion is hereinafter referred to as AR combustion.
A spark ignition type 2-cycle internal combustion engine which allows AR combustion is illustrated in FIG. 11. In a low load operating region wherein the throttle valve opening θth is restricted, thermal energy included in the combustion gas in a preceding cycle is utilized sufficiently to activate fresh air mixed with fuel in the combustion chamber. The internal combustion engine can operate in a combustion condition near to complete combustion. Therefore, the spark ignition type 2-cycle internal combustion engine exhibits a higher output power than that in an ordinary combustion condition which involves irregular combustion. As a result, where the internal combustion engine is carried on a vehicle or the like, it is disadvantageous. Even if the throttle valve opening θth is restricted, while the internal combustion engine is operating in a high speed, high load operation condition, the effect of the so-called engine brake by a sudden drop of the output power of the internal combustion engine cannot be anticipated sufficiently. The above-mentioned high speed, high load operation condition may occur from attempting to stop the vehicle quickly.
Further, when the internal combustion engine rotates in a reverse direction upon starting or when a kill switch is disconnected to stop the internal combustion engine suddenly, if the internal combustion engine is in an AR combustion state, then it is difficult to quickly stop the internal combustion engine.
SUMMARY AND OBJECTS OF THE INVENTION
The present invention relates to improvements relating to a combustion control apparatus for a spark ignition type 2-cycle internal combustion engine which eliminates the drawbacks described above. A combustion control apparatus for a spark ignition type 2-cycle internal combustion engine is provided wherein fresh air mixed with fuel in a combustion chamber can be self-ignited at least in a low load operation region. The combustion control apparatus includes exhaust path opening adjustment means for adjusting the opening of an exhaust path to control the compression starting cylinder pressure. In addition, control means for driving the exhaust path opening adjustment means to an exhaust path opening corresponding at least to an internal combustion engine speed is provided. A throttle valve opening is provided to control the compression starting cylinder pressure to an aimed compression starting cylinder pressure wherein fresh air mixed with fuel in the combustion chamber can be self-ignited at an ignition timing preferable for operation of the internal combustion engine. The exhaust path opening adjustment means is driven, when, upon development of a stopping signal for the internal combustion engine, the internal combustion engine speed is higher than a predetermined speed higher than an idling speed. Therefore, the exhaust path opening may be higher than an opening at which self-ignition is impossible. In the case when the internal combustion engine stopping signal is developed, when the internal combustion engine speed drops until it becomes lower than the predetermined speed or is lower than the predetermined speed, the exhaust path opening adjustment means is driven so that the exhaust path opening may be controlled to an opening wherein ordinary combustion is possible. The active thermal atmosphere combustion speed is hereinafter referred to as AR combustion speed.
Since the present invention is constructed as described above, when a signal for stopping the internal combustion engine is developed, if the internal combustion speed is higher than the predetermined speed higher than the idling speed, then the exhaust path opening adjustment means is driven so that the exhaust path opening becomes higher than the opening at which self-ignition is impossible. In addition, an AR combustion operation condition having high output power is bypassed or the AR combustion operation condition is cancelled. Consequently, the output power of the internal combustion engine drops remarkably to allow for quick stopping of the internal combustion engine.
Further, in the present embodiment, in the case when a signal for stopping the internal combustion engine is developed, when the speed of the internal combustion engine drops until it becomes lower than the required speed or is lower than the predetermined speed, the exhaust path opening adjustment means is driven so that the exhaust path opening is controlled to an opening at which ordinary combustion is possible. Also, when the internal combustion engine is started again after the internal combustion engine is stopped, the starting performance is maintained at a high level.
In this manner, in the present invention, when it is required to stop the internal combustion engine suddenly, the internal combustion engine can be stopped suddenly. Furthermore, once the internal combustion engine is stopped, the internal combustion engine can be readily started.
Further, upon sudden stopping of the internal combustion engine, the present invention permits a high output power and prevents active thermal atmosphere combustion with a higher degree of certainty.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustn only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustn only, and thus are not limitative of the present invention, and wherein:
FIG. 1 is a vertical sectional side elevational view taken along a cylinder portion of a spark ignition type 2-cycle internal combustion engine 1 which includes a combustion control apparatus of the present invention;
FIG. 2 is a side elevational view of the cylinder portion showing a side face of the internal combustion engine illustrated in FIG. 1;
FIG. 3 is a horizontal sectional plan view taken along line III--III of FIG. 1;
FIG. 4 is a view of an entire control system of the embodiment shown in FIG. 1;
FIG. 5 is an enlarged side elevational view of a throttle valve of FIG. 1;
FIG. 6 is a vertical sectional side elevational view of FIG. 5;
FIG. 7 is a vertical sectional view taken along line VII--VII of FIG. 6;
FIG. 8 is a vertical sectional side elevational view in a condition wherein atmospheric air pressure is introduced into a diaphragm chamber of an idling opening setting diaphragm;
FIG. 9 is a vertical sectional side elevational view in a condition wherein an intake negative pressure is introduced into the diaphragm chamber of the idling opening setting diaphragm;
FIG. 10 is a characteristic diagram illustrating a relationship between the internal combustion engine speed and the exhaust path opening of the embodiment of the present invention; and
FIG. 11 is a characteristic diagram illustrating variations of an average effective pressure in an ordinary combustion condition and an AR combustion condition when a throttle valve in a spark ignition type 2-cycle internal combustion engine is varied.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following, an embodiment of the present invention shown in FIGS. 1 to 9 is described. A spark ignition type 2-cycle internal combustion engine 1 which includes a combustion control apparatus of the present invention is carried on a motorcycle not shown. In the spark ignition type 2-cycle internal combustion engine 1, a cylinder block 3 and a cylinder head 4 are placed one on the other on and integrally coupled to a crankcase 2.
A piston 6 is fitted for upward and downward sliding movement in a cylinder bore 5 formed in the cylinder block 3. The piston 6 and a crank 8 are connected to each other by a connecting rod 7 so that the crank 8 is driven to rotate as the piston 6 moves upwardly and downwardly.
Further, an intake path 10 is connected to a crank chamber 9 in the crankcase 2, and a carburetor 11 and a reed valve 13 are interposed in series in the intake path 10. As shown in FIG. 6, a throttle valve 12 of the carburetor 11 is connected to a throttle shaft 16 via a rod 14 and a link arm 15. The throttle shaft 16 is connected to a throttle drum 17 via a throttle adjustment mechanism 35 which will be hereinafter described. The throttle drum 17 is connected to a throttle grip not shown by a wire 18 so that, if the throttle grip is turned in an accelerating direction, then the throttle drum 17 is rotated in the counter-clockwise direction to lift the throttle valve 12 to increase the throttle valve opening.
Furthermore, the intake path 10 is connected to the crank chamber 9 of the crankcase 2, and a scavenging port 19 and an exhaust port 20 are open to an inner peripheral face of the cylinder bore 5. The scavenging port 19 is communicated with the crank chamber 9 by a scavenging path 21 and the exhaust port 20 is communicated with an exhaust path 22.
Meanwhile, an ignition or spark plug 24 is provided in a combustion chamber 23 at an upper portion of the cylinder bore 5. Fresh air mixed with fuel mixed with fuel which is supplied from the carburetor 11 is taken into the crank chamber 9. The crank chamber 9 is subjected to negative pressure by an upward stroke, via the reed valve 13, and compressed in a downward stroke. When the piston 6 moves down until the scavenging port 19 is opened, the compressed fresh air mixed with fuel is supplied from the scavenging port 19 into the combustion chamber 23. As a result of admission of the compressed fresh air mixed with fuel, part of the combustion gas in the combustion chamber 23 is discharged from the exhaust port 20 to the exhaust path 22. When the scavenging port 19 is closed and the exhaust port 20 is closed by upward movement of the piston 6, the fuel air mixture in the combustion chamber 23 is compressed as a result of the upward movement of the piston 6. When the piston is in the proximity of the top dead center, ignition by the ignition plug 24 or self-ignition by thermal energy of remaining gas of the preceding cycle is performed.
Further, near the exhaust port 20, an exhaust control valve 25 is provided which serves as an exhaust path opening adjustment means. The exhaust control valve 25 is fitted in a gap 28 formed by a recess 26 provided in the cylinder block 3. The recess has an arcuate vertical sectional shape. Furthermore, an exhaust path member 27 is formed in an arcuate vertical sectional shape substantially the same as that of the recess 26. The gap 28 has a substantially uniform gap width. The exhaust control value 25 is supported for upward and downward rocking motion around a center line C. A driving lever 30 shown in FIG. 2 is integrally fitted on a drive shaft 29 integral with the exhaust control valve 25. The driving lever 30 is connected to a pulley 33 of an exhaust control servo motor 32 by a driving cable 31. Consequently, the exhaust control valve 25 is driven to rock upwardly and downwardly by the exhaust control servo motor 32 so that a required exhaust path opening θe between 0% or several percent to 100% may be set.
In addition, the horizontal transverse section of the exhaust control valve 25 has a channel-like shape. The a side face arm portion 25b of the exhaust control valve 25 is fitted in a gap portion 34 positioned outwardly of the exhaust path 22 so that the side face arm portion 25b, except for the arcuate portion 25a of the exhaust control valve 25 which closes the exhaust port 20, does not improperly influence the flow of exhaust gas.
The throttle adjustment mechanism 35 interposed between the link arm 15 integral with the throttle shaft 16 and the throttle drum 17 is constructed as shown in FIGS. 7 to 9.
First, the throttle shaft 16 is supported for rotation on a carburetor operation section body 36 by a pair of bearings 37 (at the left end and the center in the figures) over an axial direction. A sleeve 38 is fitted at a substantially central portion of the throttle shaft 16 while a base end tubular portion 15a of the link arm 15 is fitted around an outer periphery of the sleeve 38 as shown in FIGS. 6 and 7. A bolt 39, extending through the base end tubular portion 15a of the link arm 15 and the sleeve 38, is screwed on the throttle shaft 16, and the link arm 15 is coupled integrally to the throttle shaft 16.
Meanwhile, a thrust receiving washer 40 is abutted with the left end (right end in FIG. 7) of the carburetor operation section body 36. The thrust receiving washer 40 is fitted on the throttle shaft 16, and a sleeve 42 is fitted leftwardly (rightwardly in FIG. 7) of the thrust receiving washer 40 for rotation on the throttle shaft 16 with a bearing 41 interposed therebetween. An oil seal housing 43 and an idling control lever 45 are coupled integrally on the sleeve 42 and an oil seal 44 is interposed between the carburetor operation section body 36 and the thrust receiving washer 40 in the oil seal housing 43. A pair of oil seals 46 are provided at the opposite ends of the throttle shaft 16 such that the throttle shaft 16 is sealed in the carburetor operation section body 36 and the sleeve 42 by the oil seals 46.
The throttle drum 17 is fitted for rotation at a left portion (right portion in FIG. 7) of the throttle shaft 16 with a bearing 47 interposed therebetween. A thrust receiving washer 48 is abutted leftwardly (rightwardly in FIG. 7) of the throttle drum 17. A throttle lever 49 is integrally fitted to the left end of the throttle shaft 16, and a throttle return spring 50 is interposed between the idling control lever 45 and the throttle drum 17 on an outer periphery of the sleeve 42.
Furthermore, a pair of stopper bosses 51a and 51b and a deceleration opening stopper 52 are provided and project on a left side face (right side face in FIG. 7) of the throttle drum 17. A pair of engaging pieces 53a and 53b are provided on the throttle lever 49 such that the throttle lever 49 may be rocked within a range of a small angle with respect to the throttle drum 17 until it is engaged with the stopper boss 51a and the stopper boss 51b. A further engaging piece 53c is provided on the throttle lever 49. The engaging piece 53c extends towards the idling control lever 45 through a window 17a of the throttle drum 17 until it is engaged with a lug 45a of the idling control lever 45.
Further, as shown in FIGS. 8 and 9, a deceleration opening screw 55 is inserted and screwed in a receiving piece 54 integral with the carburetor operation section body 36. A lock nut 56 is screwed in the deceleration opening screw 55. One end 57a of a lever return spring 57 is anchored at the receiving piece 54. The other end 57b of the lever return spring 57 is anchored at the engaging piece 53c of the throttle lever 49. Consequently, by the spring force of the lever return spring 57, the throttle lever 49 is biased in a throttle returning direction, that is, in the clockwise direction in FIGS. 8 and 9. The engaging piece 53b of the throttle lever 49 is engaged with the stopper boss 51b of the throttle drum 17 so that the throttle drum 17 is biased in the same direction. Consequently, the deceleration opening stopper 52 provided on the throttle drum 17 is arrested by an end of the deceleration opening screw 55.
Further, the idling control lever 45 extends in the rearward direction of the vehicle (in the rightward direction in FIGS. 8 and 9) and is connected at an end thereof to a lower end of a connection member 60c of an idling opening setting diaphragm 60 (a horizontal direction displacement of the connection portion from the connection member 60c caused by rocking motion of the idling control lever 45 is absorbed by a mechanism not shown). A lower engaging piece 45b of the idling control lever 45 is engaged with an end of a stop screw 59 provided on a body of the idling opening setting diaphragm 60.
Referring to FIG. 4 which illustrates essential parts of the spark ignition type 2-cycle internal combustion engine 1, a fuel tank 61 is connected to a fuel reception chamber 11a (refer to FIG. 6) of the carburetor 11 by a fuel supply tube 62. A tube 63 is connected at an end thereof to a pipe 60b which is open to a diaphragm chamber 60a of the idling opening setting diaphragm 60 and is connected at the other end thereof to an outputting portion 64a of an idling solenoid 64. An inputting portion 64b of the idling solenoid 64 is connected to an air cleaner 68 via a tube 65, a coupling 66 and another tube 67. Another inputting portion 64c of the idling solenoid 64 is connected to an end of a tube 70 in which a check valve 69 is interposed. The other end of the tube 70 is connected to the intake path 10. In an inoperative condition of the idling solenoid 64, the diaphragm chamber 60a of the idling opening setting diaphragm 60 is in communication with the air cleaner 68 so that atmospheric air pressure is introduced into the air cleaner 68. However, in an operative condition of the idling solenoid 64, the diaphragm chamber 60a is in communication with the intake path 10 so that negative pressure is introduced into the air cleaner 68.
In addition, an inputting portion 71a of a slow jet control solenoid 71 is connected to the air cleaner 68 via a tube 72, the coupling 66 and the tube 67. An outputting portion 71b of the slow jet control solenoid 71 is connected to a slow jet portion of the carburetor 11 via a tube 73. Thus, in an inoperative condition of the slow jet control solenoid 71, air is not introduced into the slow jetting portion of the carburetor 11, and fuel is not supplied into the intake path 10 from the slow jet portion of the carburetor 11. On the contrary, in an operative condition, air is introduced into the slow jet portion of the carburetor 11 and fuel is supplied into the intake path 10 from the slow jet portion of the carburetor 11.
Further, as shown in FIG. 7, a throttle opening sensor 74 formed from a potentiometer or the like is directly coupled to the throttle shaft 16 so that a throttle valve opening θth of the throttle valve 12 is inputted to an electronic control unit 80 from the throttle opening sensor 74.
Furthermore, two pursers 75 and 76 spaced from each other by a predetermined angle in a circumferential direction are disposed sidewardly in the neighborhood of the crank 8. An internal combustion engine speed Ne and a reverse rotation are detected by the pulsers 75 and 76 and inputted to the electronic control unit 80.
A water temperature gage 77 for detecting the water temperature of cooling water which flows into the spark ignition type 2-cycle internal combustion engine 1 and a shift drum 78 of a gear transmission, not shown, are additionally provided. A shift position sensor 79 for detecting the neutral, first speed, second and third speed, fourth speed, and fifth and sixth speed positions of the transmission is provided. Detection signals of the water temperature gage 77 and the shift position sensor 79 are inputted to the electronic control unit 80.
Further, a clutch switch 81 exhibits an off state when a clutch, not shown, is in a connected condition but exhibits an on state when the clutch is in a disconnected condition. A side stand switch 82 exhibits an off state when a side stand, not shown, is in an erected condition but exhibits an on state when the side stand is in a fallen condition. A combination switch 83 is switched on when a key not shown is inserted and operated. A kill switch 84 is provided for a steering handle bar not shown and exhibits an on state when the steering handle bar is not in an operated condition is provided. The above-mentioned switches are connected to the electronic control unit 80 as shown in FIG. 4.
Next, the electronic control unit 80 delivers a control signal to the exhaust control servo motor 32 so that the exhaust path opening θe may be lower than a predetermined value when the internal combustion engine speed Ne detected by the pulsers 75 and. 76 is higher than 2,500 rpm and the throttle valve opening θth detected by the throttle opening sensor 74 is within the range of 8 to 20% while the air fuel is 13 to 15. Consequently, under those conditions, the spark ignition type 2-cycle internal combustion engine 1 is controlled to an AR combustion condition.
Then, the AR combustion condition is maintained while the internal combustion engine speed Ne remains within a range having a center value substantially at 3,500 rpm and ranging 2,500 rpm to 4,500 rpm as shown in FIG. 10.
On the other hand, if the internal combustion engine speed Ne is higher than an idling speed (1,300 rpm) and
1. the combination switch 83 or the kill switch 84 is switched off in a condition wherein the combination switch 83 and the kill switch 84 are on and spark ignition type 2-cycle internal combustion engine 1 is operating,
2. a condition wherein the spark ignition type 2-cycle internal combustion engine 1 rotating in a reverse direction is detected from signals of the pulsers 75 and 76, or
3. it is detected by the side stand switch 82 that the side stand is erected in a condition wherein the gear transmission is set to a speed position other than the neutral position,
a driver will return the throttle grip to its original stopping position. In this instance, no control signal is developed from the electronic control unit 80, and the idling solenoid 64 is in an inoperative condition. Consequently, atmospheric pressure is introduced into the diaphragm chamber 60a of the idling opening setting diaphragm 60 so that the idling control lever 45 is pushed down and the throttle lever 49 and the link arm 15 are rotated in the clockwise direction in FIGS. 8 and 9 via the lug 45a of the idling control lever 45 and the engaging piece 53c. Consequently, the throttle valve 12 is restricted to a condition close to a substantially fully closed condition and the spark ignition type 2-cycle internal combustion engine 1 is decelerated suddenly.
If the internal combustion engine speed Ne becomes lower than 2,000 rpm, then the idling solenoid 64 is put into an operative condition by a control signal from the electronic control unit 80. Consequently, an intake negative pressure of the intake path 10 is introduced into the diaphragm chamber 60a of the idling opening setting diaphragm 60, and the idling control lever 45 is pulled upwardly. Thereupon, the throttle lever 49 and the link arm 15 are pivoted in the counterclockwise direction so that the throttle valve opening θth of the throttle valve 12 is increased slightly such degree that idling is possible. In addition, the exhaust control servo motor 32 is rendered operative by a PWM (pulse width adjustment) control signal from the electronic control unit 80 so that the exhaust control valve 25 is opened to an ordinary exhaust path opening θe.
On the other hand, if the exhaust control valve 25 comes into a disabled condition, then the electronic control unit 80 does not supply current to the exhaust control servo motor 32 so that the exhaust control servo motor 32 is stopped.
Further, when the gear transmission is set to the neutral position while the side stand is erected and no detection signal is developed from the side stand switch 82, the throttle valve 12 is set to a throttle valve opening θth of such a degree that idling is possible while the exhaust control valve 25 is set to a high exhaust opening oe so that idling is possible.
Furthermore, in the electronic control unit 80, when the water temperature detected by the water temperature gage 77 is lower than 60° C., a control signal is not delivered to the slow jet control solenoid 71 and a slow air jet, not shown, remains in an inoperative condition. However, if the detected water temperature of the water temperature gage 77 becomes higher than 60° C., then a control signal is delivered to the slow jet control solenoid 71 so that the slow air jet, not shown, is rendered operative and control of the requested air fuel of AR combustion is performed. Consequently, the driving stability of on-road and off-road compatibility and improvement in fuel consumption are allowed.
In addition, if the clutch, not shown, is disconnected and the clutch switch 81 is turned on, then a map for exclusive use is selected. In a no load operation of the internal combustion engine, AR combustion control is not performed.
Since the embodiment shown in the drawings is constructed in such a manner as described above, in a stopping condition of the spark ignition type 2-cycle internal combustion engine 1, the exhaust control valve 25 is restricted to a comparative low exhaust path opening θe of such a degree that idling operation is possible. Then, in a cranking condition of a starting open, since the exhaust control valve 25 is kept to this exhaust opening θe, compression of fuel air mixture in the combustion chamber 23 is performed appropriately. Further, since intake air negative pressure is introduced into the diaphragm chamber 60a and the throttle valve 12 is opened a little, supply of fresh air mixed with fuel is performed. Consequently, the startability is improved.
After starting the spark ignition type 2-cycle internal combustion engine 1, if the throttle grip is operated in an opening direction to increase the internal combustion engine speed Ne, then an AR combustion region is entered as shown in FIG. 10 and the exhaust path opening θe of the exhaust control valve 25 is slightly further restricted. Consequently, AR combustion is allowed, and the spark ignition type 2-cycle internal combustion engine 1 can be operated stably and the fuel cost is maintained at a high level.
Further, as the internal combustion engine speed Ne increases, as shown in FIG. 10, it comes out of the AR combustion region and the exhaust path opening θe of the exhaust control valve 25 increases in a corresponding relationship. Consequently, the spark ignition type 2-cycle internal combustion engine 1 can operate in an ordinary combustion condition.
Furthermore, if, in a high speed operation condition, it becomes necessary to decelerate or stop the spark ignition type 2-cycle internal combustion engine 1 urgently in such a case as 1., 2, or 3. as described hereinabove, as indicated by a dotted line in FIG. 10, the throttle valve 12 is restricted to a fully closed condition while the exhaust path opening θe of the exhaust control valve 25 is kept in a condition near to a fully open condition. When the internal combustion engine speed Ne drops to 2,000 rpm, the exhaust control servo motor 32 is rendered operative to restrict the exhaust control valve 25 and an intake air negative pressure is introduced into the diaphragm chamber 60a of the idling opening setting diaphragm 60 so that the throttle valve 12 is slightly opened. Consequently, the spark ignition type 2-cycle internal combustion engine 1 enters an idling operation allowing condition.
If the spark ignition type 2-cycle internal combustion engine 1 is stopped, then the exhaust control valve 25 is restricted and the exhaust path opening θe is set to a low value of such a degree that idling operation is possible, a condition wherein a high starting performance can be maintained.
In this manner, when it is desired to rapidly decelerate or stop the spark ignition type 2-cycle internal combustion engine 1 in a condition wherein the spark ignition type 2-cycle internal combustion engine 1 is being operated in a high speed rotation region, since the exhaust control servo motor 32 is controlled to set the exhaust control valve 25 to a fully open condition so that the AR combustion region may be bypassed, it is easy to decelerate or stop the spark ignition type 2-cycle internal combustion engine 1 suddenly. In addition, the starting performance can be maintained at a high level. In the case of sudden deceleration, idling operation can also be performed.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. | A combustion control apparatus for a spark ignition type 2-cycle internal combustion engine includes fresh air mixed with fuel in a combustion chamber which can be self-ignited at an ignition timing preferable for the operation of the internal combustion engine at least in a low load operation region to effect active thermal atmosphere combustion. When it becomes necessary to stop the internal combustion engine quickly, upon starting of the internal combustion engine again, the starting performance is high. A combustion control apparatus for a spark ignition type 2-cycle internal combustion engine includes fresh air mixed with fuel in a combustion chamber which can be self-ignited at least in a low load operation region. The exhaust path opening adjustment means is driven upon development of a stopping signal for the internal combustion engine, if the internal combustion engine speed is higher than a predetermined speed above idle, so that the exhaust path opening is higher than an opening at which self-ignition is impossible. When the internal combustion engine stopping signal is developed, when the internal combustion engine speed drops until it becomes lower than the predetermined speed, the exhaust path opening adjustment means is driven so that the exhaust path opening is controlled to an opening at which ordinary combustion is possible. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of application Ser. No. 09/031,642, filed Feb. 27, 1998 now abandoned, which is incorporated by reference herein.
TECHNICAL FIELD
The present invention relates to bacteria cultivation and dispensing systems, and more particularly to an automatic bacteria cultivation and dispensing system that is useful for incubating bacteria from a starter population to a utility population within a predetermined interval and thereafter dispensing sufficient bacteria to perform a desired utility. A preferred utility for the disclosed system is the removal of grease from grease traps in commercial food preparation establishments.
BACKGROUND OF THE INVENTION
In the environment, bacteria are constantly working to naturally break down organic materials. This natural process generally causes some organic materials to eventually degrade into carbon dioxide and water. Under normal conditions, competition for resources, limited supplies of nutrients, and natural enemies can combine to inhibit rapid bacterial growth. By isolating selected strains of bacteria and providing a food source they prefer, bacteria can be made to multiply at a very fast rate. A large quantity of bacteria can be generated in this manner within a relatively short time. The bacteria can then be used in a wide variety of applications where the breakdown of organic materials is desirable.
One application where the breakdown of organic materials is particularly useful is in the maintenance of grease traps. Grease traps are required on virtually all commercial facilities that discard liquid or solid grease into a sewer system. Grease traps generally range from a capacity of about five gallons to over several thousand gallons. The majority of fast food kitchens are equipped with grease traps of about 1000 gallons. The system of drains used for grease traps is generally separate from the drains that carry away waste products from restrooms, spent drinking water, etc. Grease traps tend to collect not only oils and fats, but also various organic waste materials such as starches and vegetable waste products. Normally, a significant flow of wastewater is also introduced into the separate grease trap drainage system from kitchen drains where grease is often found. To prevent the wastewater from flushing grease into the city sewer system, grease traps are designed with a series of weirs that trap the grease within the containment vessel and allow wastewater to pass through the vessel on to a city treatment facility.
Inevitably, however, some of the grease in the grease trap passes into the city sewage system downstream from the restaurant. This does not create problems if the amount of grease passing into the sewer system is kept at a low level. Most city standards restrict the release of grease into sewer lines to approximately 250 ppm or less. If significant amounts of grease pass into the sewage system, the grease can cause blockages in the city pipes. When this occurs, the grease trap can overflow into the street, causing health problems. City maintenance crews often have to dig up the pipes under the street to remove the blockage. The cost of this procedure is typically passed on to the restaurant that released the grease. The restaurant usually must also pay a fine. For repeat offenders, the blockage can result in closure of the facility.
To avoid such problems, the current practice is to periodically collect the solid grease that floats on the top of the grease trap. In addition, every four to eight weeks, a service company should remove grease and other solid material that has settled and accumulated in the bottom of the grease trap, and should steam strip the walls and weirs. The cost of this service varies depending on the geographical region and the contract agreed upon by the restaurant owner and the service company, but is substantially greater over time than will be required using the system and method disclosed herein. If the grease trap is not pumped out on a regular basis, the grease layer can form such a thick crust that it blocks the inlet line into the grease trap and causes wastewater to back up into the facility. Such a back-up can require closing the restaurant or facility until the problem is resolved. Because of the potential fines and the possibility of temporary or permanent closure, maintenance of grease traps is of great importance to the owners of commercial food preparations establishments.
There are currently several products on the market that purportedly reduce the number of pump-outs needed. Many of these products are solvent-based or are detergents containing enzymes that will allegedly make the grease trap maintenance free. While many of these solvents or detergent products will dissolve the grease in the grease trap, the liquified grease often resolidifies a few feet down the sewage pipes, thereby blocking the flow of wastewater.
Another known device for treating grease traps uses bacteria in an attempt to digest the grease. The device includes a five gallon bucket that contains a bacterial gel material. Water continuously flows through the bucket and into the drain system. A disadvantage of this device is that most of the bacteria is introduced into the grease trap during periods of high kitchen activity. The volume of wastewater that flows through the grease trap flushes most of the bacteria through the grease trap and into the sewer system before the bacteria is able to digest the grease. In addition, a typical grease trap is generally a poor environment for growing bacteria rapidly due to a lack of oxygen, as well as the presence of contaminants such as detergents and antibacterial chemicals used in cleaning operations.
Another known treatment is to introduce preserved bacteria into the grease trap. This type of bacteria is generally in the form of a dry powder that consists of dormant bacteria spores. Before the growth of bacterial colonies can occur, these dormant spores must go through an incubation period to form active vegetative cells. This process takes about six hours to occur. If the spores are introduced into the grease trap before this time, most of the bacteria will be flushed from the grease trap before digestion can occur.
Another known method of maintaining a grease trap is to grow large quantities of active bacteria offsite using a filtered air supply, distilled water, and a specially designed growth chamber. The large amount of bacteria needed to sufficiently digest the grease in the grease trap, however, has not been affordable because large volumes of bacteria are expensive to produce and difficult to transport.
Applicants' copending application Ser. No. 09/031,642, filed Feb. 27, 1998, discloses an inexpensive and simple system and method for producing and dispensing large quantities of selected strains of bacteria into grease traps. That system and method are used to produce bacteria onsite in a favorable growth environment and to automatically dispense a predetermined volume of liquid containing active bacteria into the grease trap drain system during the night or at other times when flow through the trap is minimal. During use of that system, however, excessive foaming can occur in the biogeneration chamber even in the presence of an antifoaming agent due to the continuous introduction of air needed for bacterial growth through a tube having its discharge end submerged in the bacteria cultivation mixture. Such excessive foaming can cause the biogeneration chamber to overflow through the vent line, causing loss of nutrients, water and cell count, thereby slowing the desired bacterial growth.
Prior art devices said to be useful for aerating a cultivation medium within a tank, vessel or container to promote fermentation or bacterial growth are disclosed, for example, in U.S. Pat. Nos. 4,051,204; 4,426,450; 4,883,759; and 4,888,294.
SUMMARY OF THE INVENTION
The present invention comprises an automated biogeneration system and method for producing and dispensing liquid concentrates of active bacteria at predetermined intervals. According to a preferred embodiment of the invention, bacteria produced in this manner can be used to digest organic material in a grease trap and to reduce the frequency of pump-outs required. The system and method of the invention can also be used to supply bacteria for many other useful applications as disclosed below.
According to one preferred embodiment of the invention, a method for growing and selectively discharging bacteria is disclosed whereby water and a predetermined quantity of a powdered mixture of dehydrated “starter” bacteria and appropriate nutrient(s) are automatically introduced into a biogeneration chamber for the purpose of growing and quickly multiplying the selected bacteria. Multiple strains of bacteria can be used as long as the nutrient package is designed to support each of the multiple strains. Pressurized air is supplied to the chamber to support aerobic bacterial reproduction, and is desirably introduced according to a special method using a vortex that controls foaming within the biogeneration chamber. After the mixture is placed in the biogeneration chamber, the bacteria are permitted to grow and reproduce for a desired time, such as about 24 hours, while continually withdrawing liquid from the bottom of the chamber, recirculating it with a pump, and reintroducing it into the chamber in a tangentially directed flow to create the desired vortex. At the end of the growing period, the active bacteria are preferably discharged from the biogeneration chamber to another holding vessel or, more preferably, directly to a use site such as a restaurant grease trap. Once the contents of the biogeneration chamber are discharged, the process is repeated. The cycle of operation is desirably controlled by an electronic timer having relays that activate and deactivate switches and valves in accordance with predetermined parameters. Significant increases in bacterial production are observed using the system and method disclosed herein as compared to applicants' previously disclosed system and method.
According to another preferred embodiment of the invention, an automated batch system for growing and selectively discharging a bacteria-containing fluid is disclosed that comprises a biogeneration chamber having a substantially cylindrical sidewall, a top and a conical bottom, a feed source communicating with a feed inlet port in the top, a water source communicating with a water inlet port in the top, a pressurized air source communicating with an air inlet port in the top, a vent line communicating with a vent port in the top, a centrally disposed outlet port in the conical bottom, an orifice element disposed in the conical bottom at or near the outlet port, a recirculated fluid inlet port positioned and directed so as to reintroduce recirculated fluid into the chamber in a substantially tangential direction relative to the inside wall, a recirculating pump, flow tubing placing the recirculating pump inlet in fluid communication with the chamber outlet port and placing the recirculating pump outlet in fluid communication with the recirculated fluid inlet port, and a valve disposed in the flow tubing between the recirculating pump and the recirculated fluid inlet port to selectively divert flow from the pump to a drain line also communicating through the pump and the valve with the chamber outlet port.
BRIEF DESCRIPTION OF THE DRAWINGS
The preferred embodiments of the invention are further described with reference to the accompanying drawings wherein:
FIG. 1 is a simplified schematic view of a biogeneration system made in accordance with the present invention;
FIG. 2 is an enlarged, simplified front elevation view of the biogeneration chamber shown in FIG. 1; and
FIG. 3 is an enlarged, simplified front perspective view, partially broken away, depicting one orifice element as installed in the bottom of a biogeneration chamber for use in the apparatus and method of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The automated biogeneration system and method of the present invention are useful for rapidly growing a relatively large supply of selected strains of bacteria using a relatively small quantity of starter bacteria. The method of the invention provides a low maintenance, hands-free process for growing bacteria that, depending upon the bacterial strains selected, are useful in a variety of applications. Although other possible applications for the system and method disclosed herein are discussed below, a particularly preferred application is the cultivation of bacteria for use in digesting grease in grease traps such as those used in the restaurant industry. If a large enough supply of suitable, active bacteria can be introduced into a grease trap on a frequent basis, the grease accumulation inside the trap can be controlled at levels that permit less frequent pump-outs and steam cleaning of the type now regularly required. This reduces service fees and facilitates compliance with regulations governing the amount of grease that can be released into municipal sewer systems.
In accordance with a preferred embodiment of the invention, an automatic system and method are disclosed for creating large batches of active bacteria that thrive on grease and other organic matter, such as starches, sugars, and proteins. The automated function reduces labor costs, and the biogeneration chamber provides a favorable environment for growing bacteria. When introduced into a grease trap, generally through a drain line downstream of the P-trap, the large volume of bacteria produced digests some of the organic materials in the grease trap, producing carbon dioxide and water as the principal waste products.
The starter bacteria and nutrients needed to support growth and reproduction of the bacteria within the biogeneration chamber are easily transported, most preferably in powder form, making the transport of large supplies of bacteria unnecessary. The subject method does not require precise control of the temperature; nor is it necessary to use a filtered air supply or distilled water. Because multiple strains of desirable bacteria can be grown simultaneously in the same biogeneration chamber, they are capable of digesting a variety of organic materials found in grease traps while simultaneously reducing odor problems. Because they are grown onsite, the useful bacteria are active upon introduction into a grease trap. Furthermore, by introducing the bacteria during periods of low kitchen activity, the bacteria's residence time in the grease trap can be maximized.
Referring to FIG. 1, system 10 of the invention preferably comprises biogeneration chamber 12 , a feed source 24 of starter bacteria and nutrients, a feed control device 26 , a water supply, a pressurized air supply, fluid recirculation pump 62 , solenoid valves 54 and 64 , timer 68 , flow conduits 27 , 29 , 31 , 61 , 63 , 65 , 66 , 82 , 84 and 86 , and control lines 70 , 72 , 74 , 76 and 78 respectively linking timer 68 to valves 54 and 64 , air pump 60 , feed control device 26 and fluid recirculation pump 62 . The water supply is preferably fresh potable water provided to biogeneration chamber 12 at ambient temperature through flow line 80 , pressure regulator 50 , flow line 82 , filter 52 , flow line 84 , water inlet solenoid valve 54 , anti-siphon vacuum breaker 56 and flow line 27 . The pressurized air supply is preferably an air pump 60 , such as an aquarium air pump, capable of delivering to biogeneration chamber 12 a sufficient supply of air to support rapid bacterial growth at a pressure sufficient to enter the biogeneration chamber without disrupting the vortex 36 created therein as discussed below. The required air flow will of course vary according to the volume of biogeneration chamber 12 and the volume of the bacteria-containing fluid mixture 38 within the chamber. Vent line 31 i s provided to prevent pressure build-up inside biogeneration chamber 12 and is preferably filtered by filter 58 , and exhausted to atmosphere or some other type of recovery unit as desired or that may be required under special circumstances. Vent line 31 can be connected to an existing drain system downstream from the P-trap to allow venting of biogeneration chamber 12 without releasing bacteria into the kitchen area. If connected to a drain, vent line 31 can also comprise a conventional diaphragm check valve or backflow preventer (not shown in FIG. 1) to prevent unwanted bacteria from entering the biogeneration chamber 12 from the drain. useful for the intended application and nutrients needed for the starter bacteria to grow and replicate rapidly within biogeneration chamber 12 . According to a particularly preferred embodiment of the invention, the starter bacteria and nutrients are provided together in a premixed powder that is activated when hydrated and mixed in the presence of air. While the use of a dry, premixed powder feed is preferred, liquid feeds can also be used in the subject system and method, and the nutrients do not necessarily have to be premixed with the starter bacteria. Feed control device 26 can be any device or combination of devices suitable for introducing starter bacteria and nutrients into biogeneration system 12 in a controlled manner and can include, for example, a rotary valve, sliding volumetric gate, vibrating roller mechanism, weigh-belt conveyor, or the like. Alternatively, premixed powder can also be aspirated into the water inlet line using a venturi arrangement. Although a single feed source 24 and feed control device 26 are depicted in FIG. 1, it is understood that a plurality of such feed sources and/or feed control devices can also be used within the scope of the invention.
Fluid recirculation pump 62 withdraws fluid mixture 38 from biogeneration chamber 12 through outlet port 22 and line 61 , and depending upon the setting of three-way solenoid valve 64 , either returns the fluid mixture to biogeneration chamber 12 through lines 63 and 65 or else discharges the fluid mixture to a drain or other receptacle through lines 63 and 66 . Fluid recirculation pump 62 is desirably a centrifugal pump, although it is understood that diaphragm pumps and other similarly effective fluid recirculation devices can also be used within the scope of the invention. Diaphragm pumps are self-priming and are less affected by excess air in the fluid mixture. Fluid recirculation pump 62 is depicted in FIG. 1 as being controlled by timer 68 , but it is understood that pump 62 can also be controlled, for example, by electrical, mechanical, optical or ultrasonic level indicators or sensors in biogeneration chamber 12 and related switches as needed.
Timer 68 is desirably a conventional electronic control device capable of timing multiple events in the cycle of operation and signaling switches in feed control device 26 , air pump 60 , solenoid valves 54 and 64 , and fluid recirculation pump 62 in accordance with the method of the invention as described below. It will appreciated upon reading this disclosure, however, that some or all of the control functions performed by timer 68 can also be performed within the scope of the invention by the use of multiple timers, a program logic controller, a custom designed programmable circuit board, a PC based controller, pneumatic controllers, level controllers and other similarly effective means. Timer 68 will desirably accept and react to inputs from conductivity sensors, mechanical floats, optical sensors, ultrasonic sensors, and the like, and may also be capable of simultaneously operating other equipment or apparatus, whether or not depicted in FIG. 1 or described herein.
A preferred biogeneration chamber 12 for use in system 10 and the method of the invention is further described and explained in relation to FIG. 2 . Biogeneration chamber 12 preferably comprises a substantially cylindrical sidewall 14 with interior surface 16 that is smoothly and continuously joined to a conical lower section 20 having a centrally disposed chamber outlet port 22 at its lower end. Top 18 may be flat, domed o r otherwise s h aped, and is desirably removable to permit periodic cleaning of inside surface 16 of biogeneration chamber 12 . Water inlet port 28 , air inlet port 30 , feed inlet port 33 and vent port 32 are desirably provided in top 18 to communicate with water inlet line 27 , air inlet line 29 , feed control device 26 and vent line 31 , respectively. Disperser nozzle 46 is preferably provided in water inlet port 28 to direct water introduced into biogeneration chamber 12 in a 360° spray against interior surface 16 , and can also function as a rinse nozzle during clean-out of chamber 12 if desired. Orifice element 34 is preferably provided in chamber outlet port 22 to assist in controlling the amount of air entering line 61 (FIG. 1) from vortex 36 in fluid medium or mixture 38 . Too great a restriction in orifice element 34 can starve fluid recirculation pump 62 and promote plugging of the orifices.
Applicants have discovered that vortex 36 within biogeneration chamber 12 is an effective tool for mixing the bacteria and nutrients in the fluid medium and for aerating fluid mixture 38 without causing the significant amount of undesirable foam that is produced in prior art systems when air is bubbled into a biogenerator beneath the surface of a fluid mixture. The amount of aeration achieved with vortex 36 also significantly surpasses the aeration achieved when air is introduced above the fluid surface without a vortex. Vortex 36 is preferably created by the continuous reintroduction into biogeneration chamber 12 of a portion of fluid mixture 38 that is withdrawn through outlet port 22 and recirculated by pump 62 through line 63 , valve 64 and line 65 to recirculated fluid outlet port 42 disposed closely adjacent to interior surface 16 , most preferably above conical section 20 . Port 42 preferably communicates with the interior of biogeneration chamber 12 in a direction and in such manner that a continuous stream of recirculated fluid mixture 38 is reintroduced into biogeneration chamber 12 and directed horizontally along interior surface 16 in a direction that is characterized herein as being “substantially tangential” to interior surface 16 . Although the term “tangential” ordinarily refers to a line tangent to a point on the circumference of a circle or cylinder that is directed away from the curve, the term is used herein to describe a curved flowpath, initially established in a substantially horizontal direction around inside surface 16 of biogeneration chamber 12 , that diverges from horizontal as it continues around interior surface 16 and creates a downwardly spiraling vortex 36 in the center of biogeneration chamber 12 . Port 42 can be disposed in a nozzle built into sidewall 14 of biogeneration chamber 12 or can be disposed at the end of a line extending interiorly past interior surface 16 as shown in FIG. 2 . Although port 42 is shown as being elliptical in shape in FIG. 2, it will be understood that other shapes can also be used within the scope of the invention.
Orifice element 34 as shown in FIG. 2 is a cylindrical body having a top with a smaller-diameter orifice 35 and a plurality of rectangular, slot-like orifices 44 circumferentially spaced around its perimeter. It is to be understood that other orifice configurations can also be used within the scope of the present invention. As discussed below in relation to the method of the invention, orifice element 34 is useful for permitting fluid mixture 38 to be drawn into and through chamber outlet port 22 without permitting vortex 36 to continue downwardly into and through outlet port 22 , which could promote cavitation on the inlet side of fluid recirculation pump 62 .
FIG. 3 discloses an alternative structure for an orifice element 90 disposed adjacent to chamber outlet port 92 inside conical section 94 of an otherwise similar biogeneration chamber 96 . Orifice element 90 further comprises a disc 98 supported by legs 100 over outlet port 92 , and has a smaller diameter, centrally disposed aperture 102 . Disc 98 desirably has a diameter greater than that of outlet port 92 and supports vortex 104 slightly above outlet port 92 , permitting fluid mixture 108 to be drawn into outlet port 92 around and beneath disc 98 , where a smaller diameter vortex 106 is created that is less likely to cause surging, or cavitation of a fluid recirculation pump.
While the components of the invention will understandably be sized, configured and constructed according to the intended manner and place of use, satisfactory results are achieved using a one gallon bioreactor chamber 12 with a conical bottom as discussed below, a fill level within the chamber corresponding to a fluid volume ranging from about 1.5 to about 3 liters, a fluid recirculation pump 62 rated at about 3 gallons per minute, and a 50 micron inlet water filter 52 . According to a particularly preferred embodiment of system 10 of the invention for use in a typical restaurant environment to generate bacteria for discharge into a grease trap, the system components as described above can be mounted inside a cabinet and locked to prohibit access except by authorized personnel. During normal operation, infrequent access to the system is needed in order to periodically replenish the starter bacteria and nutrients. Although the time for replenishing starter bacteria and nutrients will vary according to the volume of feed source 24 and the volume of biogeneration chamber 12 , monthly replenishment should be achievable in most instances. Infrequent removal and cleaning of biogeneration chamber 12 may also be desirable following a specified number of cycles of operation, which is also anticipated to be no more often than about once a month.
According to a preferred method of the invention, described herein in relation to FIGS. 1 and 2, a dry powder containing selected bacteria cultures and dry nutrients such as sugar, refined milk protein, corn starch, and bran is loaded into feed source 24 . Desirable starter bacteria for controlling grease in a grease trap preferably include bacillus, pseudomonas, enterobacter and mixtures thereof These organisms are known to digest various types of organic waste products that are commonly found in grease traps. Preferably, the starter bacteria is stabilized with a preservative and is inactive until it is diluted with water.
At the system start-up, timer 68 activates water solenoid valve 54 , causing water to enter biogeneration chamber 12 through inlet port 28 . After passing through vacuum breaker 56 , which prevents fluid from chamber 12 from being siphoned back into the potable water system, water is sprayed into the biogeneration chamber, preferably a polyethylene container, through nozzle 46 . Water flow is continued for a predetermined time or until fluid level 49 reaches a desired point, at which time valve 54 is closed to stop the flow. Timer 68 activates feed control device 26 to dispense a predetermined quantity of powder containing starter bacteria and nutrients into biogeneration chamber 12 through suitably sized inlet port 33 , thereby hydrating and activating the starter bacteria. Air pump 60 is also activated by timer 68 and the slight positive pressure inside biogeneration chamber 12 effectively prevents unwanted bacteria from entering the biogeneration chamber after the initial start-up. Air pump 60 pumps fresh air into headspace 47 above liquid level 49 , making air readily available for vortex 36 to siphon into fluid recirculating pump 62 . The introduction of air into headspace 47 also helps carry off any gases created by the bacteria out through vent line 31 . Although some unwanted bacteria may be introduced through the air supply or water supply, growth of unwanted organisms in relatively small numbers is not usually seriously detrimental to the process and can sometimes be suppressed by carefully selecting nutrients preferred by the desired bacteria.
Once the biogeneration chamber 102 is charged with water, starter bacteria, nutrients and air, fluid recirculation pump 62 is activated, and cultivation of the selected bacteria begins. Fluid recirculation pump 62 continuously draws a stream of fluid mixture 38 from conical bottom 20 of biogeneration chamber 12 , through orifice element 34 in outlet port 22 and line 61 , to the inlet side of the pump. Fluid circulation pump 62 discharges the pressurized fluid mixture 38 into line 63 , and through three-way valve 64 , which is automatically set to return fluid mixture 38 through line 65 to inlet port 42 . As fluid mixture 38 is expelled from inlet port 42 , fluid mixture 38 is cause to swirl inside chamber 12 , desirably creating vortex 36 when the recirculation rate is properly adjusted, as for example, by controlling the pumping rate of pump 62 .
When properly adjusted in order to promote mixing and aeration, the bottom of vortex 36 will desirably extend downward to orifice element 34 in outlet port 22 . Orifice element 34 preferably prevents too much air or too little fluid mixture from entering line 61 . Too much air can damage the rotor of a centrifuigal pump and, if excessive, stall the pump. Some cavitation at pump 62 may be desirable for mixing and aeration, and partial cavitation at the pump inlet can beat air into the liquid, producing a thick froth. So long as it does not overfill biogenerator chamber 12 , some amount of foam can be desirable, increasing aeration, and also increasing the available surface area. With the present system and method, any excess foam that is created is drawn back into vortex 36 within chamber 12 and reinjected into fluid mixture 38 . The ratio of air to liquid entering line 61 can be adjusted by modifying the orifice element 34 or the recirculation rate through pump 62 . Through use of the present system and method, vortex 36 in conjunction with fluid recirculation pump 62 provides excellent mixing, aeration and foam control.
After bacterial cultivation has continued for a desired period, timer 68 or another similarly effective means causes three-way valve 64 to redirect the flow of fluid mixture 38 discharged by fluid recirculation pump 62 into drain line 66 , which can be directed to a use site or to an intermediate storage vessel. Once fluid level 49 has been pumped down to a desired point, pump 62 is deactivated and valve 64 is returned to its former position. Valve 54 is then reopened and the cycle of operation is repeated.
Although application of the invention to treat grease in a grease trap is one preferred embodiment, the invention can be equally useful in a number of other applications where large quantities of bacteria are needed. The following list includes several other illustrative examples where the invention can be used:
(1) Growing bacteria for breaking down manure and urine in cattle barns and feed lots. Use of bacteria in this manner results in a digested material that can be put directly on fields for use as a fertilizer. The pre-digestion of manure and urine allows the fertilizers and nutrients to be released into the soil much faster and with less odor problems than handling the waste material in raw form.
(2) Bacterial decomposition of agricultural waste products such as sugar cane stalks and corn stalks that are slow to degrade when left in the fields.
(3) The biological treatment of oil spills. Such treatment has generally been very expensive because of the high cost of producing live bacteria. The present invention, if used in a larger, scaled-up version, can provide a cost-effective method of growing the necessary live bacteria onsite in quantities sufficient to quickly reduce the damage to the environment.
(4) Converting PCB's created by waste materials from transformer cooling oils into less harmful substances that can be further treated. This conversion reduces the environmental problems associated with current disposal practices. Treatment of these hazardous materials is currently very expensive.
(5) Use of bacteria to accelerate the decomposition of human waste as found in portable rest rooms and in septic systems.
(6) Use of bacteria to feed on algae that forms on cooling towers and in ponds and fountains. This use would reduce the need for the use of heavily regulated toxic chemicals.
(7) Using live bacteria to control insects that infest fruit and vegetable crops, aiding in insect and disease control.
(8) Using live bacteria to control fungi in turf for golf courses, on lawns, and in other plant life. In this application, the liquid bacteria mixture could be applied directly into the irrigation system. The addition of fertilizers to the mixture would also enhance the growth of the bacteria.
(9) Treatment of soil after underground oil or gas spills have occurred. The live bacteria or other organisms could be used to more efficiently treat an oil or chemical spill area than relying on the natural bacteria in the soil to degrade the spill.
(10) Production of active yeast products for commercial bakeries.
(11) Production of yeasts used in the fermentation and production of alcohol-related products.
(12) Decomposition of industrial organic waste products before being discharged down the drains. Food and bottling plants are often assessed large fines for discharging large amounts of fats, oils, starches, and sugar-based products in excess of permissible discharge levels. The system of the present invention can be used to digest such waste products.
While the system, apparatus and method of the invention are disclosed herein in relation to their preferred embodiments, other alterations and modifications of the invention will become apparent to those of ordinary skill in the art upon reading this disclosure, and it is intended that the invention disclosed herein be limited only by the broadest interpretation of the appended claims to which the inventors are legally entitled. Those skilled in the art will also recognize upon reading this disclosure that the physical size, placement and types of bacteria, nutrient, water and air supply devices, control devices, containers and pumps can be varied or modified within the scope of the invention to meet the needs of a particular application. | An automated system and method is provided for cultivating bacteria in a fluid medium and thereafter selectively discharging the fluid medium, wherein an initial supply of the selected strain or strains of bacteria is combined with nutrients and water in a biogenerator in the presence of air to promote mixing and bacterial cultivation. The system and method utilize a vortex created by recirculation of the fluid medium to achieve aeration and mixing without substantial foaming. The system and method are particularly useful for supplying bacteria to control grease accumulation in restaurant grease traps. The system and method use a biogeneration chamber which has a cylindrical sidewall and surface on the inner side. Further, the chamber has a top and a conical bottom. The top has inlet ports and a vent port. There is also a outlet port in the conical bottom. The conical bottom also has a orifice and recirculated fluid inlet port that is directed tangentially along the inside surface of the sidewall to create a downwardly spiraling vortex in the biogeneration chamber. | 8 |
BACKGROUND
[0001] Rip-stop woven fabrics are commonly used for military and police uniforms and most rip-stop fabrics used for police and military uniforms are made in blends of polyester/cotton, cotton/polyester, and nylon/cotton. The strength, ease of care, and fade-resistance properties of rip-stop fabrics for police and military uniforms have been enhanced by this blending of polyester or nylon with cotton. Stain and water resistant finishes can be applied to the fabrics to further improve durability and ease of care.
[0002] A key requirement for rip-stop fabrics used for police and military uniforms is for them to be able to withstand 50+ washes and extensive field used while still delivering comfort to the wearer. Therefore, durability and comfort become the two most important attributes of these fabrics.
[0003] A very popular way to add comfort to a fabric is by adding stretch. Commonly, stretch has been added to fabrics by using elastic fibers, such as spandex or elastane fibers. Spandex fibers present technical challenges when used in fabrics with a polyester content higher than 40%, because spandex fiber degrades during the dyeing process as the polyester is dyed at higher temperatures than cotton or other cellulosic-based materials. In addition, spandex fibers can further degrade when stain repellant finishes are added to the fabric as they are heat-set during the finishing stage.
[0004] Further, the extensive washing cycles that police and military uniforms go through further degrade the spandex in fabric, reducing the usable life of the fabric. As a result, all the rip-stop fabrics made for police and military uniforms today that are made in polyester/cotton or nylon/cotton blends do not offer stretch properties.
BRIEF SUMMARY
[0005] The following presents a simplified summary of some embodiments of the invention in order to provide a basic understanding of the invention. This summary is not an extensive overview of the invention. It is not intended to identify key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some embodiments of the invention in a simplified form as a prelude to the more detailed description that is presented later.
[0006] Embodiments herein are directed to a rip-stop fabric incorporating mechanical stretch fibers, as opposed to elastic stretch fibers such as spandex.
[0007] In embodiments, the rip-stop woven fabric made with at least two type of yarns. The first yarn is spun from an intimate blend of staple/commercially-available fibers, with one of the fibers being cellulose-based (e.g., cotton or rayon) and the other fiber being polyester, nylon, or modacrilic. The second yarn is a filament multi-component polyester yarn or elasterell-p multi-component filament yarn.
[0008] For a fuller understanding of the nature and advantages of the present invention, reference should be made to the ensuing detailed description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a representation of a fabric in accordance with embodiments.
DETAILED DESCRIPTION
[0010] In the following description, various embodiments of the present invention will be described. For purposes of explanation, specific configurations and details are set forth in order to provide a thorough understanding of the embodiments. However, it will also be apparent to one skilled in the art that the present invention may be practiced without the specific details. Furthermore, well-known features may be omitted or simplified in order not to obscure the embodiment being described.
[0011] Embodiments herein are directed to a rip-stop fabric that features the combination of mechanical stretch, rip-stop weave, and fade resistance.
[0012] The rip-stop woven fabric is made with at least two type of yarns. The first yarn is spun from an intimate blend of staple/commercially-available fibers, with one of the fibers being cellulose-based (e.g., cotton or rayon) and the other fiber being polyester, nylon, or modacrilic (hereinafter “spun fibers” or “spun yarns”). The second yarn is a filament multi-component polyester yarn or elasterell-p multi-component filament yarn (hereinafter “multi-component polyester filament yarns” or “multi-component polyester filament fibers”). Such multi-component polyester filament yarns provide a mechanical stretch property for the rip-stop fabric.
[0013] Elasterell, or elasterell-p is a specific subclass of inherently elastic, multi-component polyester filament fibers. The U.S. Federal Trade Commission defines “elasterell-p” as fiber formed by the interaction of two or more chemically distinct polymers (of which none exceeds 85% by weight) which contains ester groups as the dominant functional unit (at least 85% by weight of the total polymer content of the fiber) and which, if stretched at least 100%, durably and rapidly reverts substantially to its unstretched length when the tension is removed. Although elasteral-p is described in embodiments, other multi-component polyester filament yarns may be used.
[0014] The multi-component filament yarn adds stretch properties to the rip-stop fabric while being able to withstand high dyeing and finishing temperatures, thereby eliminating the need to use spandex and overcoming the durability limitations of spandex.
[0015] In embodiments, a woven rip-stop fabric 10 ( FIG. 1 ) is formed by weaving multi-component polyester filament weft yarns 12 into spun warp yarns 14 . As shown in FIG. 1 , to provide a rip-stop fabric weave, the multi-component polyester filament yarns 12 are interwoven through spun yarns 14 in a plain weave fashion. However, to provide strength and rip resistance, after predetermined intervals, two or more multi-component polyester filament yarns 12 are woven together (instead of each yarn alternating, as in regular plain weave) in the same pattern through the weft yarns. Such a variation in the pattern is shown generally at the areas 16 in FIG. 1 . The pattern of weaving multiple (at least 2) adjacent weft yarns in the same weaving direction through the warp yarns is done in regular intervals. Similarly, the same one or more warp yarns may be skipped by each weft yarn during the weaving process, causing multiple spun warp yarns 12 to extend together, as shown generally at the areas 18 of the fabric 10 in FIG. 1 . The pattern of weaving multiple adjacent weft yarns in the same weaving direction and skipping at least one weft yarn consistently during weaving can be done in regular intervals, providing a crosshatch pattern in the weave. The intervals are typically 3 to 8 millimeters, but may be altered to provide a desired function. In embodiments, the interval pattern in the weft direction is the same as the warp direction, so that the crosshatch forms repeating squares.
[0016] Alternatively, the multi-component polyester filament yarns 12 may be used as weft material, and the spun fibers 14 may be woven into the multi-component polyester filament yarns, forming a ripstop pattern.
[0017] After weaving, a stain and oil repellant finish is added during the finishing process to improve fade resistance and protect the woven fabric from stains. Again, the mechanical stretch properties of the fabric, as contrasted with the more common use of spandex in stretch fabrics, enables the rip-stop fabric of the present disclosure to withstand the high temperatures involved in this finishing process.
[0018] The novel ripstop fabric described herein provides a fabric that can last many washes and that is highly suitable for police and military/militia wear, including pants or shirts. The pattern is resistant to wear, is capable of stretching for comfort, and can withstand multiple washes.
[0019] Other variations are within the spirit of the present invention. Thus, while the invention is susceptible to various modifications and alternative constructions, certain illustrated embodiments thereof are shown in the drawings and have been described above in detail. It should be understood, however, that there is no intention to limit the invention to the specific form or forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention, as defined in the appended claims.
[0020] 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. The term “connected” is to be construed as partly or wholly contained within, attached to, or joined together, even if there is something intervening. 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 embodiments of 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.
[0021] 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.
[0022] 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. | Rip-stop pants include waist and leg portions formed of ripstop fabric having synthetic mechanical-stretch filament yarns interwoven into spun, staple yarns in a ripstop pattern. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefits of Provisional Patent Application Ser. No. 61/209,059, filed 2009 Mar. 3; 61/176,668, filed 2009 May 8; and 61/182,040, filed 2009 May 28 by the present inventor.
FEDERALLY SPONSORED RESEARCH
[0002] Not applicable
SEQUENCE LISTING
[0003] Not applicable.
BACKGROUND
[0004] 1. Field of the Invention
[0005] This application relates to a power-operated urinal apparatus for a commode or a toilet and a urinal method, which prevent urine spills around the commode or toilet.
[0006] 2. Prior Art
[0007] The usage of urinals is a known method to urinate in most public restrooms. However, most residences and many commercial places do not offer the convenience of urinals. Therefore, commodes or toilets designed to receive human waste from a sitting position are also used for urination from a standing position. Typically, users stand to urinate for comfort and to avoid germs on commode seats. In the process, however, urine spills on rim of the commode and floor around the commode or toilet, no matter how careful the users may be. Even traditional urinals do not prevent urine spills and consequently odor emanates from them. Urine splashing on water of the commode bowl also leads to a sound that may be embarrassing. Urine spills result in a non-hygienic condition and require additional cleaning around the commode. Furthermore, urine spills can stain a rug, if a rug has been placed near the commode. Some users, risking the spread of germs, raise both lids of the commode to an upright position to urinate into the commode. They seldom put them back, which is inconvenience to the next user. From this point ahead in this document, “commodes or toilets” will be referred to as “commodes.”
[0008] Standard commodes and urinals are two separate fixtures requiring separate spaces, drains, and plumbing lines, which cost a lot more than a single fixture. Several attempts have been made in past to combine a urinal and a commode to provide an economical and space-saving solution. U.S. Pat. No. 6,408,449 issued to Aguirre (2002) disclosed a toilet assembly in combination with a urinal. However, this assembly can be very expensive, because it requires extra floor space and plumbing lines. Most existing toilets do not have the extra space required to add a urinal. In U.S. Pat. No. 5,655,230 issued to Corbin (1997), and in U.S. Pat. Nos. 3,412,408 and 3,500,480 issued to Michal (1968 and 1970 respectively), urinal attachments for toilet bowls are presented. Although these types of urinal attachments can be added to existing toilets, they will make the toilet space more crowded and unpleasant. These urinal attachments require skilled personnel to install the attachments resulting in extra expenses, time, efforts, and inconveniences. Other prior art devices include U.S. Pat. Nos. 3,822,419; 4,137,579; 4,180,875; and 4,750,219. Most of these prior art devices require significant modifications and plumbing changes and may be unappealing to users. U.S. Pat. No. 5,566,400 issued to Jonec (1996) disclosed a disposable flat-folded male urinary aid and compact portable dispenser. Before urinating, the male must use his hands to pull out the urinary aid from the portable dispenser, which may be unstable. Then he must unfold the long urinary aid, insert penis in larger top end and place smaller bottom end of the urinary aid into the toilet water. A lot of time is wasted doing all of these steps, even before urinating. During urination, the male must hold the urinary aid and then drop it into the toilet after use. U.S. Pat. No. 6,305,034 issued to Urrutia (2001) disclosed a wall attached extensible and retractable urine deflecting apparatus for use with a toilet. This apparatus also requires substantial use of human hands before, and after urinating. Before use, the male has to extend and after the use he has to retract the apparatus manually. Also, he has to manually lower a deflecting sheet substantially into the toilet bowl water; each use requires a substantial amount of the deflecting sheet. The deflecting sheet used in this apparatus can not reliably channel the urine flow into the toilet. Risk of urine spills still remains. Both of these prior art devices require substantial use of human hands and are unhygienic, inconvenient, and time consuming. Most of the prior art devices for urinary use of commodes have not solved the problem of urine spilling and splashing to any degree of satisfaction.
SUMMARY OF THE INVENTION
[0009] A power-operated urinal apparatus is to be used with a toilet, the toilet having an aperture for receiving human waste. The urinal apparatus comprises a supply of flushable funnels, with each flushable funnel having a top open end and a bottom open end, and a passage between the two ends, and a power-driven dispenser. The power-driven dispenser activated by a user, the dispenser being movable under power from a stored position where the dispenser allows unimpeded use of the aperture, and an extended position where the dispenser locates and holds one of the flushable funnels in a suspended position with the top end of the flushable funnel above the aperture and the bottom end of the flushable funnel located relative to the aperture to direct fluids from the flushable funnel into the aperture without requiring any contact between the user and the flushable funnel during the use of the flushable funnel. The power-driven dispenser further being operable to move the power-driven dispenser under power to cause the dispenser to release the flushable funnel into the toilet and to move the dispenser from the extended position to the stored position, without requiring any contact between the user and the flushable funnel at any time during use of the apparatus.
[0010] The flushable funnels in the supply of flushable funnels are at a first orientation and the flushable funnel in the suspended position is at a second orientation that is different from the first orientation. The flushable funnels are made of water-flushable materials tough enough to withstand fluids, slightly slippery, and have transitory water repellency. The power-driven dispenser further comprises a power-driven movable arm. The movable arm is supported by a sleeve for enabling the movable arm to move between the stored position and the extended position. The sleeve is pivotally supported with the aid of a track device for enabling the sleeve to move up and down. There is also means for holding the sleeve up to facilitate reloading a plurality of the flushable funnels to the supply of flushable funnels. The movable arm includes a means for height adjusting for a user to adjust a height of the top of the flushable funnel in the suspended position suitable to the user. The movable arm is moved between the stored position and the extended position by a rack and pinion device. The rack and pinion device is connected to a first motor. An end plate and a stop are provided on the movable arm. A movable jaw moves on the movable arm between the end plate and the stop. The end plate and the jaw releasably clamp a portion of one of the funnels.
[0011] A sensor is activated by a human user of the aperture. The sensor initiates the operation of a second motor that moves the jaw to a clamping position with the end plate before the first motor is initiated to extend the movable arm to the extended position. The supply of flushable funnels comprises a nested arrangement. Each of the flushable funnels includes a tail portion at the top end to be clamped. The sensor activation is a first activation. The sensor has a second activation by a human user when the movable arm is in the extended position. By second activation the sensor initiates the operation of the second motor that moves the jaw out of the clamping position and allows the flushable funnel in the suspended position to drop into the aperture. When the second activation of the sensors occurs and after the second motor moves the jaw out of the clamping position, the first motor moves the movable arm to the stored position. The supply of flushable funnels comprises a nested arrangement, with each flushable funnel is tapered from the top end to the bottom end. The power-driven dispenser comprises a movable arm. The supply of flushable funnels includes a biasing device to urge the flushable funnels towards an end of the movable arm.
[0012] The supply of flushable funnels includes a hub to support a plurality of flushable funnels. The supply of flushable funnels includes restraining arms with a portion extending inwards to support the hub and a biasing device to urge the flushable funnels toward an outward end of the movable arm. A protrusion is adjacent to the bottom end of the flushable funnel to cooperate with the restraining arms to dispense the flushable funnels from the nested arrangement one at a time. The flushable funnel includes a fin portion around at least a portion of the top end forming a handle. The apparatus includes storage space to store extra supplies of the flushable funnels. The apparatus includes storage space to store toilet paper. The apparatus can be made in separate sections adapted to reduce its packing size. The toilet aperture receives human waste. At least one means for fastening on an exterior of the urinal apparatus mounts the urinal apparatus to an object. The toilet has a water tank. The urinal apparatus is attached to the water tank or attached close to the toilet.
[0013] A method of assisting a standing human in urinating into a toilet designed for receiving human waste comprises the steps of providing a supply of flushable funnels, and providing a power-driven dispenser. The power-driven dispenser removing a flushable funnel from the supply of flushable funnels and by means of the power-driven dispenser, suspending the flushable funnel above the toilet to provide a path for fluids into the toilet without requiring any contact between the user and the flushable funnel during use of the flushable funnel. By means of the power-driven dispenser, releasing the suspended flushable funnel and allowing the flushable funnel to fall into the toilet without requiring any contact between the user and the flushable funnel at any time during use of the apparatus. The method further comprises the step of causing the power-driven dispenser to move the power-driven dispenser from the extended position to the stored position. The method further comprises the step of flushing the toilet to flush away the fluids and the dropped flushable funnel. The flushable funnel is suspended by way of a tail. The flushable funnel is suspended above the toilet by deploying a power-driven movable arm. The movable arm is returned to a stored position leaving the aperture to function unimpeded.
[0014] A urinal device comprises a flushable sleeve having two ends, one of the ends being larger than the other, with each end being open, and a passage between the two ends. A flap is adjacent to the smaller end and forms a handle. The flushable sleeves are made of flushable cellulosic waterleaf with minimal amount of wet strength resin from a group of melamine formaldehyde, urea formaldehyde or neutral cure wet strength, said waterleaf coated to at least one surface with a composition of 20% by weight to 70% by weight of relatively large particle size delaminated clay, with the balance being a polyethylene based resin composition produced by drying of a colloidal polyethylene in water composition together with said clay; whereby the resultant surface coating provides surface water repellency without impairing the ability of the waterleaf sleeve to be disposed of by flushing. The sleeve is part of a nested stack of sleeves.
[0015] The object of this embodiment is to provide a simpler, economical, and hygienic urinal apparatus for a commode to prevent urine spills on the rim of and floor around the commode. The apparatus does not require any additional plumbing or floor space and can be installed by a lay person within a short time.
BRIEF DESCRIPTION OF DRAWINGS
[0016] In the drawings, like reference numbers among different embodiments indicate like parts or components. Closely related figures have the same numbers but different alphabetic suffixes.
[0017] FIG. 1 is a perspective view of the preferred embodiment showing a dispensed and suspended flushable funnel ready for use.
[0018] FIG. 2 is a top cross-sectional view of the preferred embodiment, indicated by section lines 2 - 2 in FIG. 3A .
[0019] FIGS. 3A and 3B show a side cross-sectional view of the preferred embodiment, indicated by section lines 1 - 1 in FIG. 2 , with FIG. 3A showing the urinal apparatus and FIG. 3B showing a commode.
[0020] FIG. 4 is an enlarged side cross-sectional view of the preferred embodiment showing accessibility to the power-driven dispenser for restocking the funnels.
[0021] FIG. 5 shows a partial enlarged view of the operation from the stored-hub position, indicated by the dashed circle 5 in FIG. 3A .
[0022] FIG. 6 shows a cross-sectional view of the movable arm, indicated by section lines 3 - 3 in FIG. 5 .
[0023] FIG. 7 shows a partial enlarged view of the operation from the dispensed and suspended position, indicated by the dashed circle 7 in FIG. 3A .
[0024] FIG. 8 shows details of the front joint between the container and the power-driven dispenser, indicated by the dashed circle 8 in FIG. 2 .
[0025] FIG. 9 shows details of the rear joint between the container and the power-driven dispenser, indicated by the dashed circle 9 in FIG. 2 .
[0026] FIG. 10A shows a perspective view of the preferred embodiment of flushable funnel.
[0027] FIG. 10B shows a perspective view of the second preferred embodiment of the flushable funnel with fin portions added.
[0028] FIG. 10C shows a perspective view of the third preferred embodiment of the flushable funnels placed around a cardboard core in a nested arrangement.
[0029] FIG. 11 shows a perspective view of the cardboard core.
[0030] FIG. 12 shows a packaged version of the preferred embodiment.
[0031] FIG. 13 shows an unpacked version of the preferred embodiment.
[0032] FIG. 14 shows an assembly diagram of the preferred embodiment.
[0000]
DRAWINGS-Reference Numerals
100
power-operated urinal apparatus
200
commode
11
power-driven dispenser
201
commode seat
12
jaw
203
commode cover
13
movable arm
205
water tank
14
end plate
207
commode bowl
15
flushable funnel
209
wall
16
activation device or sensor
211
water supply
17
sleeve
213
drain or sewage line
18L
container
18R
container
20L
fastening device
20R
fastening device
21
drawer
22
storage section
23
hub
24
height adjusting device
25
biasing device
26
restraining arms
27
tail portion
28
reversible motor
29
reversible motor
30
switch
31
switch
32
core
33
groove
34
track
35
battery
36
electric plug
37
pivot
38
stop
39
projection
40
tongue
41
channel
42
lid
43
protrusion
44
flange
45
ball
46
socket
47
fin portion
48
notch
49
band
50
sear
51
rack
52
pinion
DETAILED DESCRIPTION OF EMBODIMENTS
FIGS. 1 , 2 , 3 A- 3 B and 10 A
[0033] The invention may be best described by reference to the drawings. One preferred embodiment of the power-operated urinal apparatus 100 for a commode 200 is illustrated in various views: FIG. 1 (perspective view), FIG. 2 (top view), FIGS. 3A and 3B (side cross-sectional view), and FIG. 10A (flushable funnel). Part number follows name of the part. The apparatus 100 is attached on water tank 205 of the commode 200 by fastening devices 20 L and 20 R, which can be suction cups or other suitable fastening devices. The fastening devices are built under a storage section 22 , but can be built anywhere on the apparatus 100 . The fastening devices secure the apparatus on top of the water tank or on a wall near the commode. This position allows the commode to function unimpeded. A power-driven dispenser 11 is attached to the storage section 22 , which has a drawer 21 and can store extra flushable funnels 15 . The dispenser 11 has a truncated cone shaped hub 23 to support the flushable funnels 15 in nested arrangement. The funnels 15 are ready to be dispensed one at a time. A movable arm 13 is provided in the dispenser 11 to extend, and suspend a funnel 15 above the commode bowl 207 when activated by a user. This extended position converts the commode into a temporary urinal without requiring any contact between the user and the funnel.
[0034] A plurality of restraining arms 26 having a portion extending inwards to support the hub 23 . The restraining arms 26 are flexible enough to release one funnel 15 at a time with cooperation of a biasing device 25 . The biasing device 25 is located between the rear wall of the dispenser 11 , and the hub 23 . The restraining arms 26 are anchored to the dispenser 11 . The biasing device 25 pushes the hub 23 outward when the outer most funnel 15 is pulled out of the nested stack of funnels 15 . This push is just enough to automatically place the newly exposed tail portion 27 of the next outer most funnel 15 close to an end plate 14 located on outer end of the movable arm 13 . The positioning of the tail portion 27 keeps the outer most funnel 15 ready to be clamped by a jaw 12 against the end plate 14 . The movable arm 13 is supported by a sleeve 17 for enabling the arm 13 to move between the stored position and the extended position when activated. The movable arm 13 also has a height adjusting device 24 , which may be a constant torque friction hinge or other suitable device. The device 24 helps a user to adjust the height of top end of the funnel in suspended position suitable to the user.
[0035] The movable arm 13 is moved between the stored and extended positions by a suitable rack and pinion device connected to a reversible motor 29 . The motor 29 is connected to a battery 35 and an electric plug 36 for choice of a power supply. A switch 30 is provided on the end plate 14 to activate forward movement of the movable arm 13 . A stop 38 is provided on the movable arm 13 . A switch 31 is provided on the stop 38 to activate reverse movement of the movable arm 13 . A suitable rack and pinion device is connected to a reversible motor 28 that moves the jaw 12 between the end plate 14 and the stop 38 . The motor 28 is connected to the battery 35 and the electric plug 36 for choice of a power supply. An activation device 16 is provided, which can be a touchless sensor or a switch. The sensor 16 is placed on the stop 38 but can be placed anywhere on the apparatus 100 . The first user activation of the sensor 16 is to move the arm 13 from the stored position to the extended position to suspend and hold a funnel 15 . The second user activation of the sensor 16 is to drop the funnel and return the arm 13 from the extended position to the stored position. The apparatus has lidded containers 18 L and 18 R on either side of the dispenser 11 , which can store extra toilet paper rolls.
[0036] In operation, upon first activation by a user, the sensor 16 initiates the operation of the motor 28 that moves the jaw 12 forward thereby clamping the tail portion 27 of the outer most funnel 15 with the end plate 14 . Simultaneously, the jaw 12 activates the switch 30 and stops. This activation initiates operation of the motor 29 that extends the movable arm 13 to the extended position. While extended out, the arm 13 pulls out the clamped outer most funnel 15 from the nested stack of the funnels 15 loaded on the hub 23 . Once the funnel 15 is pulled out completely from the stack (when the larger rear end of the funnel pulled out of the stack), the funnel 15 swings from the near horizontal orientation (shown in solid lines in FIG. 3A ) to a near vertical orientation (shown in dashed lines in FIG. 3A ) due to gravity. This suspended funnel above the commode directs fluids from the user into the commode. This operation does not require any contact between the user and the funnel during use of the funnel. The motor 29 stops when the movable arm 13 is fully deployed. The funnel 15 can help to reduce embarrassing sounds due to the urine stream hitting the inner sides of the funnel 15 instead of the water in the commode bowl. The user can adjust height of the top end of the funnel 15 by moving the deployed arm 13 up or down, as needed.
[0037] When the movable arm is in the extended position, and the user has finished urinating, the user activates the sensor 16 . Upon this second activation, the sensor 16 initiates the operation of the motor 28 that moves the jaw out of the clamping position allowing the funnel 15 in the suspended position to drop into the commode bowl 207 . Immediately following, the jaw 12 activates the switch 31 initiating the operation of the motor 29 . This motor 29 moves the arm 13 to the stored position leaving the commode 200 to function unimpeded. The jaw 12 on the arm 13 clears the tail portion 27 and allows it to lift up. The jaw 12 has a tapered thin leading edge to move under the tail portion 27 . Upon flushing, the dropped biodegradable funnel 15 flushes away with the urine and degrades in the sewage line. The first and second activations by the user can be done without touch, such as by waving a hand near or above the sensor 16 . On the next activation, the operation repeats.
[0038] FIG. 1 is a perspective view of the urinal apparatus 100 placed on the water tank 205 of the commode 200 . The movable arm 13 is extended by the power-driven dispenser 11 suspending a funnel 15 over the commode bowl 207 ; it is now ready for use. This is the temporary conversion of the commode 200 to a urinal. The jaw 12 is holding a suspended funnel 15 against the end plate 14 . The dispenser 11 is placed on the storage section 22 . The drawer 21 is drawn slightly open to show that it can store extra funnels 15 . Containers 18 L and 18 R are drawn open to show that they can store toilet paper rolls. The sensor 16 is placed on the stop 38 but it can be placed anywhere on the apparatus. First activation of the sensor 16 moves the jaw 12 forward clamping the funnel 15 and activating the switch 30 . This activation extends the arm 13 forward and suspends the funnel 15 . Second activation of the sensor 16 moves the jaw backward dropping the funnel 15 and activating the switch 31 . This activation returns the arm 13 into the apparatus. The full operation is discussed previously, and in FIG. 3A , FIG. 5 , and FIG. 7 .
[0039] In phantom lines, FIG. 1 illustrates the commode 200 , which includes commode seat 201 , commode cover 203 , water tank 205 , and commode bowl 207 . The commode may be positioned against a wall 209 and is connected to a water supply 211 and a drain line 213 (see FIG. 3B ).
[0040] FIG. 1 further shows the urinal apparatus 100 includes the fastening devices 20 L and 20 R (only one 20 L is visible in FIG. 1 ), which attach the apparatus 100 to the water tank 205 . Additionally, the storage section 22 can be placed so that the drawer 21 can open from the left side or from right side; it can also be opened from the front or can be designed with a lids on any side. The dispenser 11 , the storage section 22 including the drawer 21 , the containers 18 L and 18 R, can be made from rigid or semi-rigid plastic or other suitable materials.
[0041] FIG. 1 further shows the movable arm 13 has the height adjusting device 24 such as a constant torque friction hinge. The device 24 allows the user to position the height of the top end of the funnel 15 over the toilet to a suitable height; the device 24 holds the position until second activation of the sensor 16 moves the arm 13 back into the dispenser 11 . Several constant torque friction hinges are available in the market, such as Reell's patented hinge.
[0042] FIG. 2 is a top cross-sectional view of the urinal apparatus 100 showing the dispenser 11 including the hub 23 . The containers 18 L and 18 R can store toilet paper rolls or other items. The restraining arms 26 are anchored to the dispenser 11 . Along with the hub 23 , the restraining arms 26 supports a plurality of the funnels 15 placed on the hub 23 . The biasing device 25 pushes the hub 23 outwards. The movable arm 13 (not shown on FIG. 2 ), with cooperation of the restraining arms 26 , dispenses a funnels 15 one at a time. The restraining arms 26 can have a portion extend inwards to hold the protrusions 43 (not shown on FIG. 2 ) of the funnels 15 . The arms 26 are flexible enough to release the funnels 15 one at a time. Details at dashed circle 8 and 9 are shown in FIGS. 8 and 9 , respectively.
[0043] In phantom lines, FIG. 2 shows the commode seat 201 in seating position, the commode cover 203 in upright position, the water tank 205 below the apparatus 100 , and the commode bowl 207 of the commode 200 .
[0044] In dashed lines, FIG. 2 show fastening devices 20 L and 20 R, which can be made of flexible plastic suction cups or other appropriate fastening device. The fastening devices 20 L and 20 R are built below the apparatus 100 and are sized to fit on and secure to the water tank 205 . The apparatus 100 can be made attachable to the water tank or an object including a wall by way of suitable fastening device.
[0045] FIG. 3A and FIG. 3B show a side cross-sectional view of the urinal apparatus 100 for a commode 200 . In solid lines, FIG. 3A shows the apparatus 100 storing a plurality of funnels 15 in nested arrangement around the hub 23 and a funnel 15 has not been dispensed. The movable arm 13 is in the stored position (shown in solid lines). Upon first activation by a user, the sensor 16 initiates the operation of the motor 28 that moves the jaw 12 forward thereby clamping the tail portion 27 of the outer most funnel 15 with the end plate 14 . Simultaneously, the jaw 12 activates the switch 30 , which initiates the operation of the motor 29 to extend the movable arm 13 to the extended position (shown in dashed lines). While extending out, the arm 13 pulls out the clamped funnel 15 from a nested stack on the hub 23 . Once the funnel 15 is pulled out completely from the stack (when the larger rear end of the funnel is pulled out of the stack), the funnel 15 swings from the near horizontal orientation (shown in solid lines in FIG. 3A ) to a near vertical orientation (shown in dashed lines in FIG. 3A ) due to gravity. The lower end of the funnel 15 positions itself over the bowl 207 such that the urine flows into the bowl 207 . The user urinates though the funnel 15 . During pull of the funnel 15 , the biasing device 25 pushes the hub 23 forward. This positions the next outer most funnel 15 and its tail portion 27 close to the end plate 14 , ready for next user.
[0046] When the movable arm is in the extended position (shown in dashed lines), the user activates the sensor 16 . This second activation initiates the operation of the motor 28 that moves the jaw 12 out of the clamping position. This allows the suspended funnel 15 to drop into the commode bowl 207 . Immediately following, the jaw 12 activates the switch 31 initiating the operation of the motor 29 , which then moves the arm 13 to the stored position. This stored position keeps the commode to function unimpeded. On the next first and second activation, the respective operation repeats. A sleeve 17 , which can be a plate, a cylinder or other suitable device, supports the movable arm 13 . A pivot 37 and tracks 34 attached on both sides of the dispenser 11 support the sleeve 17 . The apparatus 100 is attached by fastening devices 20 L, and 20 R (not shown in FIG. 3A ). The storage section 22 may include a drawer 21 to store extra funnels 15 . The movable arm 13 has the height adjusting device 24 for the users to adjust the height of top of the funnel 15 at a suitable height. The motor 28 and 29 can be operated by the battery 35 or the electric plug 36 . The details of the operation at dashed circles 5 and 7 are shown in FIGS. 5 and 7 , respectively.
[0047] In phantom lines, FIG. 3A shows the top part of the commode 200 , which can be positioned adjacent to a wall 209 . The apparatus 100 can be placed on the water tank 205 (showed in partial view). The water tank is for flushing the commode 200 . The commode cover 203 , in upright position, appears in partial view.
[0048] In phantom lines, FIG. 3B shows the commode 200 , which can be used in conjunction with the urinal apparatus 100 (shown in FIG. 3A ) to convert the commode into a urinal. The commode 200 includes the commode seat 201 , the commode cover 203 , the water tank 205 , and the commode bowl 207 . The commode may be positioned against the wall 209 . Water supply 211 supplies water to the water tank 205 . The commode is connected to the drain 213 .
[0049] FIG. 4 is an enlarged side cross-sectional view of the urinal apparatus 100 . The sleeve 17 can be moved upward and then reverted back to its original position with aid of the pivot 37 and the tracks 34 . A ball 45 mounted on the sleeve 17 snaps into a socket 46 mounted on a lid 42 to hold the sleeve 17 in upward position, as needed. This feature allows a wider front opening of the dispenser 11 to restock a plurality funnels 15 on the hub 23 , as needed. Different methods can be used for this purpose. The hub 23 is storing a plurality of funnels 15 in nested arrangement. A user activation of the sensor 16 activates the apparatus 100 to convert a commode in to a temporary urinal.
[0050] FIG. 4 further shows the lid 42 that may be opened to install the battery 35 , which can be regular or rechargeable. Several regular or rechargeable batteries are available in the market. Optionally, the electric plug 36 can be used to plug into an electrical wall outlet for direct electric power supply to the apparatus 100 .
[0051] FIG. 5 shows a partial enlarged view of the apparatus at dashed circle 5 in FIG. 3A . The funnels 15 are stacked in a nested arrangement around a core 32 . The core 32 facilitates insertion of the funnels 15 on the hub 23 . The reversible motor 28 and the jaw 12 are connected through a rack and pinion device. The motor 28 is attached to the pinion. The jaw 12 is attached to the rack. The reversible motor 29 and the movable arm 13 are connected through a rack and pinion device. The motor 29 is attached to the pinion. The movable arm 13 is attached to the rack.
[0052] FIG. 5 further shows that the funnel 15 has not been dispensed. The movable arm 13 is in the stored position. Upon first activation by a user, the sensor 16 initiates the operation of the motor 28 . This operation moves the jaw 12 forward, and clamps the tail portion 27 of the outer most funnel 15 with the end plate 14 . Simultaneously, the jaw 12 activates the switch 30 , which initiates the operation of the motor 29 . This process moves the movable arm 13 to the extended position suspending a funnel 15 above the commode. After activating the switch 30 the jaw 12 stops. While extended out, the arm 13 pulls out the clamped outer most funnel 15 from a nested stack of funnels 15 loaded on the hub 23 . Near the end plate 14 , only one tail portion 27 (of the outer most funnel 15 ) remains exposed to be clamped. Because of the nested arrangement, the tail portion 27 of each funnel 15 in the stack is buried below the next funnel 15 stacked above it. Therefore, only one funnel 15 is pulled out at a time—when the user activates the sensor 16 . The remaining funnels of the stack remain in place on the hub 23 . The restraining arms 26 hold the protrusion 43 of the next funnel 15 in line to be dispensed (not shown in FIG. 5 ). In this process, the biasing device 25 (not shown in FIG. 5 ) pushes the hub 23 forward, which positions the tail portion 27 of the next forward most funnel 15 close to the end plate 14 . On the next first activation, the process repeats. The jaw 12 can have a tapered thin leading edge to move under the raised tail portion 27 of the outer most funnel 15 . The battery 35 or the electric plug 36 supplies the power.
[0053] FIG. 6 shows a cross-sectional view of the movable arm 13 , indicated by section lines 3 - 3 in FIG. 5 . Upon activation, the jaw 12 slides on the movable arm 13 , forward on the first activation, and reverse on the second activation. A pair of tongues 40 and a pair of grooves 33 keep the reversible jaw 12 aligned and stay on the same plane even while moving. Different methods can be used for this purpose. The tongues 40 are located on both opposite inner sides of the jaw 12 . The tongues 40 of the jaw 12 slide in the grooves 33 , which are located on both outer sides of the arm 13 . The rack 51 of the rack and pinion device is attached to the under surface of the top side of the reversible jaw 12 . The pinion 52 is attached to the reversible motor 28 . The motor 28 is mounted at the underside of the arm 13 and attaches to the rack 51 through an opening in the arm 13 . The tail portion 27 , the switch 30 , and the end plate 14 are as previously discussed.
[0054] FIG. 7 shows a partial enlarged view of the operation from the dispensed and suspended position of the funnel 15 , indicated by the dashed circle 7 in FIG. 3A (the dashed lines of FIG. 3A are shown in solid lines in FIG. 7 ). When the movable arm 13 is in the extended position, the user initiates a second activation of the sensor 16 after urinating. The sensor 16 initiates the operation of the motor 28 to move the jaw 12 out of the clamping position and allows the flushable funnel 15 in the suspended position to drop into the commode bowl 207 . Immediately following, the jaw 12 activates the switch 31 . The switch 31 initiates the operation of the motor 29 , which moves the arm 13 to the stored position. The commode 200 is now free to function unimpeded (not shown in FIG. 7 ). When the arm 13 returns fully in the dispenser 11 , the jaw 12 clears the tail portion 27 of the next outer most funnel 15 and allows the tail portion 27 to lift up (not shown in FIG. 7 ). On the next second activation, the process repeats. The activation device or sensor 16 is mounted on stop 38 but can be located anywhere on the apparatus 100 (not shown in FIG. 7 ). The end plate 14 is housing the switch 30 .
[0055] FIG. 8 shows a detail of the front joint, indicated by the dashed circle 8 in FIG. 2 . The joint is between the front left corner of the container 18 R and the front right side of the dispenser 11 secured by a channel 41 . The joint can be nailed, screwed, glued or attached by other suitable method. The commode cover 203 is visible in the FIG. 8 .
[0056] FIG. 9 shows a detail of the rear joint, indicated by the dashed circle 9 in FIG. 2 . The joint is between the rear left corner of the container 18 R and the rear right side of the dispenser 11 secured by the channel 41 . The joint can be nailed, screwed, glued or attached by other suitable method. The restraining arm 26 is anchored to the dispenser 11 .
[0057] FIG. 10A shows a perspective view of the preferred embodiment of the flushable funnel 15 in a near horizontal orientation. The funnel 15 has a predetermined truncated cone shape, and is made of biodegradable materials. The materials can be compounds or papers having wet strength and water repellency while retaining the property of being flushable. The funnel 15 retains its strength and shape temporarily when wetted. Such papers can be manufactured. For example, an invention in U.S. Pat. No. 4,920,171 assigned to Monadnok papers Mills, Inc. (Bennington, N.H.) presented a paper product suitable for applications requiring wet strength and water repellency while retaining the property of being flushable. The invention in U.S. Pat. No. 4,920,171 can be used in its entirety for manufacturing the flushable funnels 15 . The invention in U.S. Pat. No. 4,920,171 is directed to a coating composition for application to a flushable cellulosic based waterleaf sheet to impart transitory water repellency to at least one surface of the sheet. The composition comprises between about 20% by weight to about 70% by weight of relatively large particle size delaminated clay in combination with a polyethylene based polymer that has been produced by the drying of a colloidal polyethylene in water composition with the said clay. Being flushable, the funnel 15 paper have minimum wet strength resin, such as melamine formaldehyde, urea formaldehyde, or a neutral cure wet strength material. Furthermore, the funnel 15 is strong enough to withstand the force of a urine stream. The funnel 15 material can be made moderately slippery so that it can slide out easily from a stack of the funnels 15 stored around core 32 (not shown FIG. 10A ). Each funnel 15 has two ends and a passage extending through between the ends. The funnel 15 is tapered so as to have a small end and a larger end.
[0058] FIG. 10A further shows the funnel 15 has a tail portion 27 attached on one side of the small open end. The funnel 15 has protrusion 43 all around the larger open end to allow for grip by the restraining arms 26 (not shown on FIG. 10A ). The protrusion 43 cooperates with the restraining arms 26 and the biasing device 25 to dispense one funnel 15 at a time from the nested arrangement. The funnel 15 can be of different suitable shapes and sizes including, but not limited to square, round, oval, rectangular, or polygon. The funnel 15 can be made of suitable lengths to suit different sizes of commodes.
[0059] FIG. 10B shows another embodiment of the funnel 15 in a near horizontal orientation. In addition to the entire characteristic described in FIG. 10A including the tail portion 27 and the protrusion 43 , the funnel 15 has fin portions 47 on the remaining sides of the small open end. The fin portions 47 on two sides can be used as handles and can be held by both hands while urinating; the portion 47 on the remaining side (close to the user) can act as a guard against dripping urine. This embodiment can be used with or without the apparatus 100 . Without the apparatus 100 (not shown in FIG. 10B ), the funnel 15 can be held in hands over the commode bowl. Then it can be dropped after the use, and can be flushed away.
[0060] FIG. 10C shows another embodiment of the funnel 15 , which is arranged in a nested arrangement around the core 32 . In addition to the entire characteristic described in FIG. 10A including the tail portion 27 forming a handle, the funnel 15 has a fin portion 47 on the opposite side of tail portion 27 forming another handle. The two handles can be held by a user above the commode bowl for urinating standing in the commode without the use of the apparatus 100 (not shown in the FIG. 10C ). After the use, the user can drop the funnel 15 in the commode bowl. Then it can be flushed. The funnels 15 can be with or without the protrusion 43 . This embodiment can be stored on top of the water tank or near the toilet. A single funnel 15 can be pulled out of the stack when needed. Since the bottom end is larger than the top end, the stack of funnels 15 stays stable at the stored position.
[0061] FIG. 11 shows a perspective view of the core 32 , which can be made from cardboard or another suitable material and thickness. Its function is similar to the cardboard core of toilet paper rolls. The core 32 has a flange 44 for pulling it out from the hub 23 (not shown in FIG. 11 ). The core 32 can be disposable or refillable.
[0062] FIG. 12 shows a compact packing version of the apparatus 100 to save space and cost. The drawer 21 is slightly open showing that the dispenser 11 can be placed inside the drawer 21 . A side of the containers 18 L and 18 R adjacent to the dispenser 11 is precut leaving a small slit on either end of that side. These slits fit into grove of the channels 41 (not shown in FIG. 12 ) attaching the containers 18 L and 18 R to the dispenser 11 . With these precut sides the containers 18 L and 18 R can be wrapped around the storage section 22 as shown. Thus, the packing can be made smaller. The packing version occupies less space than the assembled one and may cost less than the assembled one. A consumer can easily assemble it.
[0063] FIG. 13 shows how to unpack different components of the urinal apparatus. First, separate the container 18 L and the container 18 R from both ends. Then slide out the drawer 21 from the storage section 22 . Take out the dispenser 11 from the drawer 21 . Thus, the apparatus can be made ready to be assembled.
[0064] FIG. 14 shows an assembly diagram of the urinal apparatus for a commode. First, place and push the storage section 22 slightly on the top surface of the water tank 205 (not shown in FIG. 14 ). The fastening device 20 L and 20 R (not shown in FIG. 14 ) attaches the apparatus on the water tank 205 (not shown in FIG. 14 ). The storage section 22 can be positioned to access the drawer 21 from the left or right side. Next, the dispenser 11 slides and fits on a notch 48 located on the storage section 22 . Bands 49 slide in sears 50 , which lock in the dispenser 11 with the storage section 22 . Then, slide the containers 18 L and 18 R in the groove formed by channels 41 . This compact version is just one example, and can be made in several different ways. Thus, a consumer can easily assemble the apparatus in a short time.
ADVANTAGES
[0065] The power-operated urinal apparatus for a commode alleviates deficiencies of prior arts in the same field and provides further benefits including:
[0066] (a) Prevents urine spills around the commode.
[0067] (b) Reduces splashing and embarrassing sounds of urine stream.
[0068] (c) Requires no additional floor space.
[0069] (d) Requires no additional plumbing work.
[0070] (e) Installs easily by a layperson in a short time.
[0071] (f) Has a storage space for extra flushable funnels and toilet paper rolls.
[0072] (g) Is hygienic, economical, novel, unique, useful and pleasing.
CONCLUSION, RAMIFICATIONS, AND SCOPE
[0073] Thus, at least one embodiment of the urinal apparatus for a commode provides a more reliable, clean, and economical apparatus that can be used by a wide range of people. Said apparatus facilitates urinal function without installing a traditional urinal and extra plumbing. Said apparatus is easy to install and is aesthetically pleasing than a urinal and can work better than the prior art. As an added bonus, said apparatus stores extra bio-degradable funnels and toilet papers.
[0074] The elements described here can be duplicated or eliminated, changed in size and made in different shapes and colors. They can be connected or associated with adjacent elements in a different manner. They can be made integrally or separately, i.e. modular or in sections.
[0075] While my above description contains much specificity, these should not be construed as limitations on the scope, but rather as an exemplification of one preferred embodiment thereof. Accordingly, the scope should be determined not by the embodiments illustrated, but by the appended claims and their legal equivalent. | A urinal apparatus for a commode converts the commode into a temporary urinal. Upon its first motion activation by a standing user, a reversible jaw moves forward and holds a biodegradable funnel against an end plate of a movable arm. Simultaneously, the reversible jaw pushes first switch causing the movable arm to move forward dispensing and suspending the funnel above the commode bowl. The user urinates through the funnel, which channels the urine down into the commode bowl preventing urine spillage around the commode. When through urinating, and second motion activation by the user, the reversible jaw moves backward releasing the used funnel, which drops into the commode bowl. Immediately following, the reversible jaw pushes second switch causing the movable arm to retract into the apparatus leaving the commode to perform its original function unimpeded. Flushing drains away used funnel in sewage system served by the commode where it degrades. | 4 |
This is a continuation of application Ser. No. 07/675,625, filed on Mar. 27, 1991, which was abandoned on Dec. 23, 1992.
FIELD OF THE INVENTION
The present invention relates to a pressure control valve for use in an automobile braking system, which pressure control valve is capable of continuously controlling a hydraulic brake pressure supplied to a wheel cylinder of the automobile braking system.
DESCRIPTION OF THE PRIOR ART
Japanese Laid-Open Patent Publication No. 1(1989)-178062, for example, discloses a proportional solenoid-operated pressure regulating valve for use in an automobile braking system. The disclosed pressure regulating valve includes a housing having inlet ports connected to hydraulic pumps of the automobile braking system, output ports connected to wheel cylinders, and a relief port connected to a reservoir. The pressure regulating valve also includes spools slidably disposed in the housing for establishing selective communication between the various ports when axially moved by the combination of propulsive forces produced by linear solenoids mounted on the housing and hydraulic brake pressures from the wheel cylinders. The hydraulic brake pressures applied to the wheel cylinders can be controlled in proportion to electric currents supplied to the linear solenoids.
Since, however, the hydraulic brake pressures applied to the wheel cylinders are proportional to the electric currents supplied to the wheel cylinders, the wheel cylinders will not be supplied with any hydraulic brake pressures if no electric signal is supplied to the linear solenoids. Stated otherwise, in the event of an electric failure, such as a wire disconnection, of the linear solenoids or the electric signal transmission system of the automobile braking system, no electric signal can be supplied to the solenoids, resulting in a brake system failure.
SUMMARY OF THE INVENTION
In view of the aforesaid drawback of the conventional pressure control valve, it is an object of the present invention to provide a pressure control valve for use in an automobile braking system, which pressure control valve is capable of continuously controlling a hydraulic brake pressure supplied to a wheel cylinder of the automobile braking system in response to an applied electric signal, and also can allow the automotive brake system to perform its normal function even in the event of an electric failure, such as a wire disconnection, of the electric signal transmission system of the automobile braking system.
According to the present invention, there is provided a pressure control valve for use in an automobile braking system having a pressure fluid source, a wheel cylinder, and a reservoir, the pressure control valve comprising a slidable member slidably movable from a first position in which the pressure fluid source and the wheel cylinder communicates with each other through the slidable member for introducing a pressure fluid from the pressure fluid source into the wheel cylinder, through a second position in which the slidable member holds a fluid pressure in the wheel cylinder, to a third position in which the wheel cylinder communicates with the reservoir through the slidable member for discharging the pressure fluid from the wheel cylinder to the reservoir, pressure-bearing means associated with the slidable member for applying a first biasing force to the slidable member to urge the slidable member to the third position in response to the fluid pressure from the wheel cylinder, electromagnetic force generating means responsive to an electric signal for generating an electromagnetic force to urge the slidable member to the third position, biasing means for normally applying a second biasing force, greater than the first biasing force, to the slidable member to urge the slidable member to the first position, and means for regulating the fluid pressure in the wheel cylinder to cause the sum of the fluid pressure in the wheel cylinder and the electromagnetic force from the electromagnetic force generating means to counterbalance the second biasing force from the biasing means, whereby the fluid pressure in the wheel cylinder can continuously be controlled.
When no electric signal is applied to the electromagnetic force generating means, the slidable member is subjected to the first biasing force produced in response to the fluid pressure from the wheel cylinder and the second biasing force from the biasing means. Since the second biasing force is greater than the first biasing force, the slidable member is moved to the first position, bringing the pressure fluid source and the wheel cylinder into communication with each other.
When an electric signal is applied to the electromagnetic force generating means, the electromagnetic force is additionally applied to the slidable member. The slidable member is now shifted until the first biasing force, the second biasing force, and the electromagnetic force are counterbalanced. If the slidable member is located out of the second position, then the hydraulic braking pressure in the wheel cylinder varies, thus varying the first biasing force. The slidable member finally moves into the second position, bringing the first biasing force, the second biasing force, and the electromagnetic force into equilibrium.
Therefore, the hydraulic braking pressure in the wheel cylinder is uniquely determined and hence can be continuously be controlled by the electric signal applied to the electromagnetic force generating means.
The above and other objects, features and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings in which preferred embodiments of the present invention are shown by way of illustrative example.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a pressure control valve according to a first embodiment of the present invention, the pressure control valve being incorporated in an automobile anti-skid braking system;
FIGS. 2A, 2B, and 2C are fragmentary cross-sectional views showing the manner in which the pressure control valve shown in FIG. 1 operates;
FIG. 3 is a diagram showing the relationship between an electromagnetic force produced by the pressure control valve shown in FIG. 1 and a hydraulic braking pressure in a wheel cylinder;
FIG. 4 is a cross-sectional view of a pressure control valve according to a second embodiment of the present invention;
FIG. 5 is a cross-sectional view of a pressure control valve according to a third embodiment of the present invention;
FIG. 6 is a block diagram of another automobile anti-skid braking system which incorporates a pressure control valve according to the present invention;
FIG. 7 is a flowchart of of a control sequence for actuating a pressure control valve according to the present invention under duty cycle control; and
FIG. 8 is a diagram showing the waveform of a drive signal applied to actuate the pressure control valve under duty cycle control.
DETAILED DESCRIPTION
Like or corresponding parts are denoted by like or corresponding reference numerals throughout views.
FIG. 1 shows a pressure control valve, in cross section, according to a first embodiment of the present invention, and a hydraulic circuit arrangement of an automobile anti-skid braking system, in block form, particularly for one wheel of an automobile.
As shown in FIG. 1, the pressure control valve, generally designated by the reference numeral 1, is hydraulically connected to a master cylinder 23 actuatable by a brake pedal 24, a wheel cylinder 27 associated with an automobile wheel 34, and a reservoir 30 coupled to a hydraulic pump 31.
The master cylinder 23 communicates with an inlet port 14a of the pressure control valve 1 through a pipe 25, and the wheel cylinder 27 communicates with an outlet port 14b of the pressure control valve 1 through a pipe 26. The pressure control valve 1 also has a return port 14c communicating with the reservoir 30 through a pipe 29. A hydraulic brake fluid stored in the reservoir 30 is drawn by the pump 31 and returned through a pipe 32 to the master cylinder 23.
The pressure control valve 1 includes a cup-shaped housing 2 made of a magnetic material. The housing 2 is fastened to another housing 14 by bolts (not shown). The ports 14a, 14b, 14c are defined in the housing 14. The housing 2 accommodates therein an electromagnetic coil 3 disposed in a resin-molded case, a plate 6 of a magnetic material inserted in the housing 2 and held against an end of the coil 3, a cylindrical sleeve 28 of a nonmagnetic material disposed in the coil 3 and brazed to the plate 6, and a core 5 of a magnetic material disposed in the sleeve 28. The housing 14 accommodates a cylinder 10 disposed therein and a cap 12 held against an inner end of the cylinder 10. In the cylinder 10, there is slidably disposed a stepped spool 7 having axially spaced portions of different diameters D1, D2 (D1>D2).
The stepped spool 7 has two slots 7a, 7b defined in outer circumferential surfaces thereof. The inlet and outlet ports 14a, 14b can communicate with each other through the slot 7a and fluid passages 10a, 10b which are defined in the cylinder 10. The cylinder 10 also has a pressure chamber 33 defined therein at an end of the flow passage 10b near the stepped spool 7. A hydraulic brake pressure for the wheel cylinder 27 is introduced into the pressure chamber 33. The stepped spool 7 has a recess 7c defined in its outer periphery and opening into the pressure chamber 33. The axially spaced portions of different diameters D1, D2 are divided by a step which is defined by the recess 7c. The outlet port 14b and the return port 14c can communicate with each other through the fluid passage 10b, the pressure chamber 33, the slot 7b, a chamber 36 defined in the cap 12 and communicating with the slot 7b, and a fluid passage 12a defined in the cap 12. The chamber 36 communicates through a fluid passage 10c defined in the cylinder 10 with a chamber 35 which is defined axially between the stepped spool 7 and the core 5. Therefore, the same hydraulic pressure acts in the two chambers 35, 36 at all times.
The core 5 houses therein a spring 8 which acts on the stepped spool 7 for normally urging the stepped spool 7 to move in a leftward direction (FIG. 1). The stepped spool 7 supports on its lefthand end a shutoff valve 11 which holds the chamber 36 and the fluid passage 12a out of communication with each other under the bias of the spring 8. The shutoff valve 11 is also subjected to a rightward force from a spring 13, the force from the spring 13 being smaller than the force from the spring 8. When the stepped spool 7 moves to the right, the shutoff valve 11 also moves to the right while being pressed against the stepped spool 7 under the bias of the spring 13, thereby allowing communication between the chamber 36 and the fluid passage 12a.
A ring 9 of a nonmagnetic material is fixed to an outer step of the core 5 which faces the stepped spool 7. When the stepped spool 7 moves to the right under electromagnetic forces produced by the coil 3 as it is energized, the stepped spool 7 abuts against the ring 9, but not the core 5. If the stepped spool 7 were allowed to abut against the core 5, the stepped spool 7 would remain attracted to the core due to residual magnetism even after the coil 3 is de-energized. Since the cylindrical sleeve 28 is nonmagnetic, a magnetic path is established by the coil 3, the core 5, the stepped spool 7, and the plate 6, allowing the electromagnetic forces from the coil 3 to act effectively on the stepped spool 7.
An O-ring 15 and a backup ring 19 are disposed between the core 5 and the sleeve 28. O-rings 16, 17 and backup rings 20, 21 are disposed between the cylinder 10 and the housing 14. An O-ring 18 and a backup ring 22 are disposed between the cap 12 and the housing 14.
The wheel 34 is associated with a wheel speed sensor 37 which generates a pulsed signal depending on the rotational speed of the wheel 34. The brake pedal 24 is associated with a brake switch 34 which is turned on only when the brake pedal 24 is stepped on. Output signals from the wheel speed sensor 37 and the brake switch 34 are supplied to an electronic control unit (ECU) 39. Based on the supplied signals, the ECU 39 calculates the rotational speed of the wheel 34 and determines a locked condition of the wheel 34, and then supplied a drive signal to the coil 3 of the pressure control valve 1 to regulate the hydraulic brake pressure to be supplied to the wheel cylinder 27.
Operation of the automobile anti-skid braking system shown in FIG. 1, including the pressure control valve 1, will be described below.
(i) Normal Braking Mode
When the wheel 34 is braked normally, the coil 3 is not energized and hence no electromagnetic forces are produced thereby. The stepped spool 7 and the shutoff valve 11 are pressed to the left under the resiliency of the spring 8, closing the fluid passage 12a with the shutoff valve 11. The hydraulic braking pressure which is produced by the master cylinder 23 when the brake pedal 24 is depressed flows through the pipe 25, the inlet port 14a, the fluid passage 10a, and the slot 7a into the pressure chamber 33, and then through the fluid passage 10b, the outlet port 14b, and the pipe 26 into the wheel cylinder 27. At this time, the slot 7b does not communicate directly with the pressure chamber 33. However, since the braking fluid leaks through the clearance between the cylinder 10 and the stepped spool 7 which is axially slidable therein, the slots 7a, 7b and the chambers 33, 36 are maintained under the same fluid pressure as the hydraulic braking pressure in the wheel cylinder 27. The braking fluid does not flow from the pressure control valve 1 into the reservoir 30 because the fluid passage 12a connected through the return passage 14c to the reservoir 30 is positively closed by the shutoff valve 11.
(ii) Anti-Skid Braking Mode
When the wheel 34 is likely to lock up by a braking action while the automobile is running, an anti-skid braking mode is initiated, and the pressure control valve 1 regulates the hydraulic braking pressure to be supplied to the wheel cylinder 27. More specifically, the coil 3 is energized to produce a electromagnetic attractive force Fc to move the stepped spool 7 to the right (FIG. 1). When the stepped spool 7 moves to the right, the shutoff valve 11 also moves to the right under the bias of the spring 13, thus opening the fluid passage 12a which communicates with the return port 14c. The chamber 36 is therefore brought into communication with the reservoir 30. Consequently, the hydraulic pressure in the chamber 36 and the chamber 35 which communicates with the chamber 36 through the fluid passage 10c drops down to zero, so that the hydraulic braking pressure in the wheel cylinder 27 is reduced.
At this time, the hydraulic braking pressure in the wheel cylinder 27, i.e., the hydraulic pressure in the pressure chamber 33, is regulated as follows:
As described above, the diameter D1 of the portion of the stepped spool 7 which is on the righthand side of the recess 7c is greater than the diameter D2 of the portion of the stepped spool 7 which is on the lefthand of the recess 7c. Therefore, the hydraulic pressure in the pressure chamber 33, i.e., the hydraulic braking pressure Pw/c in the wheel cylinder 27, acts on the difference A=(D1 2 -D2 2 )·π/4 between the cross-sectional areas of the smaller- and larger-diameter portions of the stepped spool 7. The stepped spool 7 is now subjected to a rightward force Fp=Pw/c·A which depends on the hydraulic braking force Pw/c applied to the wheel cylinder 27. At the same time, the stepped spool 7 is subjected to the rightward electromagnetic force Fc produced by the coil 3, as described above, and also to a combined force Fs from the springs 8, 18 (=the biasing force from the spring 8--the biasing force from the spring 13). The stepped spool 7 moves into a stable position until the sum of the forces Fp, Fc is equalized to, i.e., counterbalances, the force Fs (Fp+Fc=Fs). When the stepped spool 7 is stopped in equilibrium, the hydraulic braking force Pw/c in the wheel cylinder 27 is uniquely determined depending on the electromagnetic force Fc according to the following equation:
Pw/c=(Fs-Fc)/A.
The stepped spool 7 is automatically moved until the state of balance as defined by the above equation is reached. The automatic movement of the stepped spool 7 will be described below in greater detail with reference to FIGS. 2A, 2B, and 2C.
FIGS. 2A, 2B, and 2C show the pressure chamber 33 and surrounding parts at enlarged scale. When the hydraulic braking pressure Pw/c satisfies the above equation, the stepped spool 7 is positioned as shown in FIG. 2A. When the hydraulic braking pressure Pw/c is higher than the force indicated by the righthand side of the above equation, the stepped spool 7 is positioned as shown in FIG. 2B. When the hydraulic braking pressure Pw/c is lower than the force indicated by the righthand side of the above equation, the stepped spool 7 is positioned as shown in FIG. 2C.
When the hydraulic braking force Pw/c satisfies the above equation, the pressure chamber 33 does not communicate directly with both the slots 7a, 7b of the spool 7, as shown in FIG. 2A, so that the hydraulic braking pressure Pw/c is kept at a constant level. At this time, a small amount of braking fluid actually flows into and out of the chamber 33 through the clearance between the stepped spool 7 and the cylinder 10. However, since the hydraulic pressure in the pressure chamber 33 is kept constant, no braking fluid can apparently be regarded as flowing into and out of the pressure chamber 33.
If the electromagnetic force Fc is increased, the forces are brought out of the state of balance as defined by the above equation, and the stepped spool 7 is moved to the right as shown in FIG. 2B. The slot 7b communicates with the pressure chamber 33, allowing the braking fluid to flow from the pressure chamber 33 through the slot 7b, the chamber 36, the fluid passage 12a, the return port 14c, and the pipe 29 into the reservoir 30. Therefore, the hydraulic braking pressure Pw/c acting in the pressure chamber 33 is reduced, thereby reducing the force which pushes the stepped spool 7 to the right. Then, the stepped spool 7 starts to move gradually to the left. As the hydraulic braking pressure Pw/c is reduced until the above equation is satisfied, the stepped spool 7 moves back to the position shown in FIG. 2A, keeping the hydraulic braking pressure Pw/c constant again.
Conversely, if the electromagnetic force Fc is reduced, the stepped spool 7 is moved to the left as shown in FIG. 2C, bringing the slot 7b into communication with the pressure chamber 33. The braking fluid flows from the master cylinder 23 through the slot 7a into the pressure chamber 33, resulting in an increase in the hydraulic braking pressure Pw/c in the pressure chamber 33. The pressure buildup in the pressure chamber 33 then increases the force tending to push the stepped spool 7 to the right, whereupon the stepped spool 7 starts to move gradually to the right. As the hydraulic braking pressure Pw/c is increased until the above equation is satisfied, the stepped spool 7 moves back to the position shown in FIG. 2A, keeping the hydraulic braking pressure Pw/c constant again.
As can be understood from the above description with reference to FIGS. 2A, 2B, and 2C, the hydraulic braking pressure Pw/c can be controlled by the electromagnetic force Fc. In the anti-skid braking mode, when the wheel 34 shows a greater sign of wheel locking, i.e., a stronger wheel locking tendency, the electromagnetic force Fc is increased to lower the hydraulic braking pressure Pw/c to be applied to the wheel cylinder 27, and when the wheel 34 shows smaller signs of locking, the electromagnetic force Fc is reduced to increase the hydraulic braking pressure Pw/c to be applied to the wheel cylinder 27. The slip ratio of the wheel 34 can be maintained at an appropriate level through the above control process, using the pressure control valve 1.
In the above embodiment, the electromagnetic force Fc is controlled by an electric current supplied to the coil 3. In the anti-skid braking mode, the pump 31 is actuated at all times to return the braking fluid discharged into the reservoir 30 to the master cylinder 23.
Since the hydraulic braking pressure Pw/c is continuously controlled by the pressure control valve 1, any noise which would otherwise be produced by sudden changes in pressure or shocks which would otherwise be transmitted to the brake pedal 24 can be reduced.
The shutoff valve 11 serves to prevent any braking fluid which has leaked through the clearance between the stepped spool 7 and the cylinder 10, from flowing into the reservoir 30. The shutoff valve 11 reliably closes the fluid passage 12a communicating with the reservoir 30 under the bias of the spring 8 when the coil 3 is de-energized. Therefore, inasmuch as no braking fluid is discharged from the pressure control valve 1 into the reservoir 30 in the normal braking mode, the braking pressure in the normal braking mode is not reduced, and hence the braking performance of the braking system is not impaired in the normal braking mode. The pump 31 may be actuated only in the anti-skid braking mode because the braking fluid is discharged into the reservoir 30 only in the anti-skid braking mode.
Furthermore, as shown in FIG. 3, the electromagnetic force Fc and the hydraulic braking pressure Pw/c in the wheel cylinder 27 are related such that when the electromagnetic force Fc is zero, the hydraulic braking pressure Pw/c in the wheel cylinder 27 is equal to the hydraulic pressure from the master cylinder 23, and as the electromagnetic force Fc increases, the hydraulic braking pressure Pw/c decreases. In the event of a failure of the coil 3, such as a wire disconnection of the coil 3 or the electric signal transmission system of the braking system, therefore, the hydraulic pressure from the master cylinder 23 is still able to act on the wheel cylinder 27, allowing the braking system to perform its function.
FIG. 4 shows a pressure control valve according to a second embodiment of the present invention. The pressure control valve shown in FIG. 4 includes a spool assembly composed of a spool 7S and an armature 7A, with the spool 7S being slidably disposed in a core 5', and a shutoff valve 11' disposed between the spool 7S and the armature 7A. The pressure control valve shown in FIG. 4 is smaller in size than the pressure control valve shown in FIG. 1. When the armature 7A moves to the right under electromagnetic attractive forces, the shutoff valve 11' held against the armature 7A also moves to the right, thereby opening a fluid passage 12'a defined in a cap 12' and communicating with the return port. Upon the rightward movement of the armature 7A and the shutoff valve 11', the spool 7S held against the shutoff valve 11' also moves to the right, so that the hydraulic braking pressure applied to the wheel cylinder can be regulated.
FIG. 5 shows a pressure control valve according to a third embodiment of the present invention.
The pressure control valve shown in FIG. 5 has a spool assembly composed of a spool 107S and an armature 107A, and is arranged such that the hydraulic braking pressure in the wheel cylinder acts on one end of the spool 107S and the bias forces of springs 108, 113 act in one direction on the spool 7S and the armature 7A.
The above arrangement of the pressure control valve shown in FIG. 5 allows the coil 3 to be reduced in size, the braking system to be more reliable in operation, and the pressure valve to be manufactured more easily.
The pressure control valve shown in FIG. 5 will be described in detail with respect to its structure and operation.
A pressure-bearing member 107T is held against one end of the spool 107S and has a projecting end exposed in a fluid passage 116 which is defined in a housing 114 by a cylinder 110 disposed therein. The fluid passage 116 is supplied with the hydraulic braking pressure from the wheel cylinder 27 through the pipe 26 and an outlet port 114b defined in the housing 114. The pressure-bearing member 107T is subjected to a rightward force (FIG. 5) under the hydraulic braking pressure supplied to the fluid passage 116. The force thus applied to the pressure-bearing member 107T acts on the spool 107S, urging the spool 107S to move to the right. A spring 108 acting on the other end of the spool 107S applies a force to the spool 107S in a direction opposite to the force from the pressure-bearing member 107T. The force from the spring 108 is greater than the force which is produced by the hydraulic braking pressure that is applied through the pressure-bearing member 107T to the spool 107S. Therefore, the spool 107S is normally urged to the left. Under this condition, the master cylinder 23 and the wheel cylinder 27 are held in communication with each other through the pipe 25, an inlet port 114a defined in the housing 114, a slot 107a defined in the spool 107S, a fluid passage 115 defined in the cylinder 110, the fluid passage 116, the outlet port 114b, and the pipe 26. Therefore, the braking system shown in FIG. 5 operates in the normal braking mode.
The spool 107S has a fluid passage 109 defined axially therethrough and communicating with a slot 107b defined in the spool 107S through a communication hole 136 that is defined diametrically in the spool 107S. The fluid passage 109 also communicates with a chamber 135 defined between the spool 107S and a core 105 in an electromagnetic coil 103. When a shutoff valve 111 is opened, the fluid passage 109 also with a fluid passage 110c defined in the cylinder 110 and communicating with a return port 114c defined in the housing 114. The shutoff valve 111 has a valve body fixed to the armature 107A and a valve seat 112 press-fitted in an end of the fluid passage 113. A stopper 120 has one end press-fitted in the cylinder 110 and the other end axially slidably inserted in the armature 107A with a certain clearance therebetween. When the armature 107A is axially moved with respect to the cylinder 114 under electromagnetic forces from the coil 103, the stopper 120 prevents the armature 107A from rotating about its own axis and hence the valve body of the shutoff valve 111 from being dislodged off the valve seat 112.
The spool 107S extends axially through the armature 107A. Only a stepped end of the spool 107S, which is disposed in the chamber 135, engages the armature 107. When the coil 103 is energized to attract the armature 107A to the right under an electromagnetic force, the armature 107A and the spool 107S move in unison with each other. The armature 107A is normally urged to the left by a spring 113 which is disposed around the spring 108. Therefore, when the coil 103 is de-energized, the armature 107A is pressed to the left under the bias of the spring 113.
The pressure control valve shown in FIG. 5 operates as follows:
When the coil 103 is energized, the armature 107A and the spool 107S move into a stable position in which the sum of the electromagnetic attractive force from the coil 103 and the hydraulic braking pressure from the wheel cylinder 27 counterbalances the forces from the springs 108, 113. If the slots 107a, 107b and the fluid passage 115 are not blocked at this time, then the hydraulic braking pressure in the wheel cylinder 27 is increased or reduced. The change in the hydraulic braking pressure in the wheel cylinder 27 causes the spool 107S to move into the stable position until finally the slots 107a, 107b and the fluid passage 115 are blocked (actually the same amount of braking fluid flows into and out of the fluid passage 115 through the clearance between the spool 107S and the cylinder 110. As with the pressure control valve 1 according to the first embodiment, the hydraulic braking pressure in the wheel cylinder 27 is uniquely determined by the electromagnetic force produced by the coil 103 and can continuously be controlled thereby.
In the pressure control valve 1 according to the first embodiment, when the chamber 36 and the fluid passage 12a are held out of communication with each other, the shutoff valve 11 is subjected to a leftward direction (FIG. 1) under the hydraulic braking pressure introduced in the chamber 36 because substantially no hydraulic pressure acts on the surface of the shutoff valve 11 which faces the fluid passage 12a communicating with the reservoir 30 and the hydraulic braking pressure introduced in the chamber 36 acts on the surface of the shutoff valve 11 which faces the chamber 36. Therefore, the force of the spring 13 must be strong enough to move the shutoff valve 11 even when the high-pressure braking fluid is introduced into the chamber 33. The force of the spring 8 which urges the spool 7 against the force of the spring 13 needs to be strong as well. As a result, the coil 3 must be large in size or consume a large electric current in order to produce an electromagnetic force which is strong enough to move the spool 7 against the bias of the spring 8.
According to the third embodiment shown in FIG. 5, however, the force of the spring 108 is required to be only larger than the force which acts on the spool 107S under the hydraulic braking pressure from the wheel cylinder 27. The spring 113 may be of a small force as it only needs to push the armature 107A to the left (FIG. 5). Therefore, the electromagnetic force produced by the coil 103 for moving the spool 107S and the armature 107A may be relatively small, and hence the coil 103 may be reduced in size and consume a relatively small electric current.
Moreover, even if the spring 108 is damaged or otherwise fails to function properly, the shutoff valve 111 will not be opened since the armature 107A remains to be pressed to the left by the spring 113. If the spring 113 fails or both the springs 108, 113 fail, the shutoff valve 111 remains to be closed because the hydraulic pressure acting on the surface of the shutoff valve 111 which faces the fluid passage 113 communicating with the reservoir 30 is substantially zero whereas the hydraulic braking pressure introduced in the chamber 135 is applied to the surface of the armature 107A that faces the chamber 135.
As described above, unless the coil 103 is energized to produce the electromagnetic force, the shutoff valve 111 is not opened. Consequently, even if the springs 108, 113 are damaged or fail to function properly, the braking fluid is prevented from flowing into the reservoir 30 through the shutoff valve 111, so that the braking system operates highly reliably.
According to the first embodiment shown in FIG. 1, the the spool 7 has different-diameter portions one on each side of the recess 7c, and the hydraulic braking pressure in the wheel cylinder 27 is borne by the difference between the cross-sectional areas of the different-diameter portions of the spool 7. Therefore, the space in which the spool 7 slidably moves in the cylinder 10 is required to have corresponding different-diameter portions. It is however quite difficult to machine and produce the different-diameter portions of the spool 7 and the cylinder 10.
According to the third embodiment shown in FIG. 5, however, the spool 107S and the pressure-bearing member 107T are separate members, they can easily be machined and produced.
FIG. 6 shows in block form another automobile anti-skid braking system which incorporates a pressure control valve according to the present invention, the automobile anti-skid braking system having a hydraulic booster.
The automobile anti-skid braking system includes a braking pressure generator assembly 50 including a hydraulic pressure booster 52. The braking pressure generator assembly 50 is hydraulically connected to a pressure control valve 1 through a solenoid-operated directional control valve 40 which has a port 40a connected to the pressure control valve 1, a port 40b connected to a master cylinder 53, and a port 40c connected to the hydraulic pressure booster 52. While in the anti-skid braking mode, the hydraulic pressure booster 52 is brought into communication with the pressure control valve 1 through the solenoid-operated directional control valve 40, so that the hydraulic pressure booster 52 supplies a braking fluid required to regulate the hydraulic braking pressure in the wheel cylinder. The hydraulic pressure supplied from the hydraulic pressure booster 52 is regulated so that it corresponds to the hydraulic braking pressure from the master cylinder 53. The braking fluid discharged from the pressure control valve returns to a reservoir 54 of the braking pressure generator assembly 50 through a pipe 63.
The pressure control valve according to the present invention may be incorporated in an open-loop-type anti-skid braking system as well as the closed-loop-type anti-skid braking system according to the first embodiment, wherein the braking fluid circulates in the system. In the case where the pressure control valve is incorporated in an open-loop-type anti-skid braking system, no pressure pulsations are produced, making it effective to reduce noise during operation of the braking system and also to reduce a kickback on the brake pedal.
In the above embodiments, the electromagnetic force Fc is controlled by the electric current supplied to the electromagnetic coil. However, the electromagnetic oil may be energized by a pulse drive signal as shown in FIG. 8, and the duty cycle t/T (e.g., 1 msec.<T<100 msec.) of the pulse drive signal may be controlled to control the electromagnetic force Fc.
FIG. 7 shows a control sequence for actuating a pressure control valve according to the present invention with such a pulse drive signal. The control sequence shown in FIG. 7 is executed in each predetermined period of time (e.g., 5 msec.) with respect to each of the wheels of an automobile which incorporates the anti-lock braking system with the control pressure valve.
A step 200 calculates a wheel speed Vw based on a detected signal from the wheel speed sensor 37 (FIG. 1). Then, a step 210 calculates a wheel acceleration Vw based on the wheel speed Vw calculated in the step 200, and a step 220 calculates an automobile speed Vb based on the wheel speed Vw calculated in the step 200. A step 225 calculates a reference speed Vs for determining a sign of wheel locking, i.e., a wheel locking tendency, based on the automobile speed Vb according to the following equation:
Vs=K3·Vb-K4.
A step 230 then calculates a locking parameter W representing the wheel locking tendency based on the wheel speed Vw, the wheel acceleration Vw, and the reference speed Vs according to the following equation:
W=K1(Vw-Vs)+K2·Vw.
A step 235 compares the absolute value of the locking parameter W and a predetermined value A, and, if the absolute value of the locking parameter W is greater than the predetermined value A, calculates a target hydraulic pressure change ΔP according to the following equation:
ΔP=K5·W.
If the absolute value of the locking parameter W is smaller than the predetermined value A, the target hydraulic pressure change ΔP is set to zero. In a step 240, a target hydraulic braking pressure P0 for the wheel cylinder 27 is calculated, using the target hydraulic pressure change ΔP, according to the equation:
P0=P0(n-1)+ΔP
where P0(n-1) is a target hydraulic braking pressure calculated in a previous cycle.
Based on the target hydraulic braking pressure P0 calculated in the step 240, the duty cycle of a drive signal to be supplied to the electromagnetic coil of the pressure control valve is calculated in a step 250. Then, a step 260 determines whether the presently calculated target hydraulic braking pressure P0 is equal to the previously calculated target hydraulic braking pressure P0(n-1) or not. If the presently calculated target hydraulic braking pressure P0 is equal to the previously calculated target hydraulic braking pressure P0(n-1), indicating that the absolute value of the locking parameter W is smaller than the predetermined value A, i.e., the wheel has a smaller locking tendency, then the period T of the pulse drive signal is set to a first period TH in a step 270. If the presently calculated target hydraulic braking pressure P0 is different from the previously calculated target hydraulic braking pressure P0(n-1), indicating that the wheel has a larger locking tendency, then the period T of the pulse drive signal is set to a second period TC in a step 280. The first period TH is shorter than the second period TC.
Therefore, if the wheel locking tendency is smaller and it is not necessary to change the target hydraulic braking pressure P0, the frequency of the pulse drive signal is increased, so that the spool (and the armature) is stably driven by an average current of the pulse drive signal supplied to the coil. Consequently, the amount of braking fluid flowing through the clearance between the spool and the cylinder is reduced, and so is the amount of braking fluid discharged into the reservoir. If the wheel locking tendency is larger and it is necessary to change the target hydraulic braking pressure P0, the frequency of the pulse drive signal is reduced, so that the spool (and the armature) is driven while being axially vibrated a small stroke. Accordingly, when the target hydraulic braking pressure P0 is changed, the hysteretical behavior of the spool (and the armature) when it is driven is reduced. More specifically, when the spool (and the armature) is moved, it is subjected to a resistance, which is maximum at the time the spool (and the armature) starts moving. Because the spool (and the armature) is driven while being axially vibrated a small stroke when the target hydraulic braking pressure P0 is changed, the resistance applied to the spool (and the armature) is reduced, thus reducing the hysteretical behavior of the spool (and the armature) as it is driven.
In a step 290, a pulse drive signal based on the duty cycle calculated in the step 250 and the period T established in the step 270 or 280 is applied to the electromagnetic coil.
As described above, the pressure control valve according to the present invention can continuously control the hydraulic braking pressure applied to the wheel cylinder based on the electric signal supplied to the pressure control valve. Furthermore, even in the event of an electric failure, such as a wire disconnection, of the electric signal transmission system, the pressure control valve allows the braking system to perform its normal braking function.
Although certain preferred embodiments have been shown and described, it should be understood that many changes and modifications may be made therein without departing from the scope of the appended claims. | A pressure control valve for use in an automobile braking system includes a spool slidably movable for providing selective fluid communication between a pressure fluid source, a wheel cylinder, and a reservoir. The spool has, or is associated with, a pressure-bearing member responsive to a fluid pressure from the wheel cylinder, for applying a first biasing force to the slidable member to urge the slidable member to a position in which the wheel cylinder and the reservoir communicates with each other. An electromagnetic coil responds to an electric signal for generating an electromagnetic force to urge the slidable member to the above position. The slidable member is normally biased by a spring under a second biasing force, greater than the first biasing force, to urge the slidable member to a position in which the pressure fluid source and the wheel cylinder communicate with each other. The fluid pressure in the wheel cylinder is regulated to cause the sum of the fluid pressure in the wheel cylinder and the electromagnetic force from the electromagnetic coil to counterbalance the second biasing force. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to a single-sideband radiotelephone system including at least one single-sideband transmitter and a plurality of single-side-band receivers.
As is well known, a single-sideband transmitter is designed to broadcast amplitude modulated information on a selected one of the two primary sidebands of an amplitude modulated carrier while suppressing the other sideband as well as the carrier. Since no carrier exists in the transmitted signals, a reinserted carrier is provided by a receiver, and it is with reference to this reinserted carrier that the sideband information is demodulated. The quality and frequency response of the demodulated signal depends on how accurately the frequency of the reinserted carrier is aligned with reference to the original, but now suppressed carrier. Therefore, determination of the proper insertion carrier frequency is essential if a single-sideband signal is to be demodulated accurately.
Usually, the stability of transmitters and the receivers is high enough to provide reasonably acceptable quality of voice communications. Some receivers are provided with a "clarifier" control which permits the operator to make minor adjustments in the insertion carrier frequency should the transmitter and receiver frequencies differ slightly.
There are several prior art systems which attempt to establish the proper insertion carrier frequency, one of which is shown in U.S. Pat. No. 3,716,790. In the device shown in that patent, a two-frequency tone is broadcasted continuously. For example, a F1 frequency tone is broadcast simultaneously with a selected one of an F2-F6 frequency tone. At the receiver, these two tones interact in the intermediate frequency (IF) and audio stages to produce a single audio tone having a frequency equal to the frequency difference between the two transmitted tones. The detected audio tone is independent of the frequency of the insertion carrier, and may be used as a guide in tuning the receiver. This system is wasteful of power and bandwidth in that the two frequency tones must be broadcast simultaneously during transmission of any information but do not carry any information other than to establish the proper insertion carrier frequency.
In a radiotelephone system, as well as in other systems, such as a radioteletype, a preselected receiver is accessed by means of tone coded signals which precede the broadcast of audio information. It is essential that these tone coded signals be detected and decoded properly if the preselected receiver is to be activated. In order to detect the tone coded signals, however, the detectors or filters used in the receiver will have a limited band-pass in order to provide sufficient selectivity. Therefore, the receivers must be tuned accurately in order to place the tone coded signals within the band-pass of the detectors or filters.
It is recognized, however, that within the frequency bands normally used by the radiotelephone service, frequency stability of ±0.01% for the transmitter is acceptable. Assuming a 2 MHz carrier signal, the carrier may therefore vary in frequency ±200 Hz. A similar variation in the frequency stability of the receiver could result in a total variation in the received signals of ±400 Hz. By way of example, if a single 1300 Hz audio tone were to be broadcasted, this tone could be demodulated at a receiver as a tone ranging in frequency from 900 to 1700 Hz.
Audio filters or detectors of the type normally used in receivers for this purpose have a band-pass of 8 to 10% of its center frequency or ±130 Hz, in the example given. It is therefore clear that a filter with a band-pass this narrow might not detect a 1300 Hz tone at all times, even assuming the permissable frequency variation in the transmitter.
SUMMARY OF THE INVENTION
The present invention relates to a single-sideband radio system which may be used for radiotelephone, radioteletype or for other uses in which at least two audio detectors or filters are employed, the center frequencies of which are varied relative to at least two frequency-spaced tones transmitted simultaneously for a predetermined interval in order to place the transmitted frequency-spaced tones within a band-pass of the detectors or filters.
A single-sideband transmitter includes means for broadcasting initially at least two frequency-spaced tones simultaneously for a predetermined time interval. Thereafter, these same frequency-spaced tones are broadcast alternately in a unique code pattern to access a predetermined receiver, in the case of a radiotelephone system, or to convey information, in the case of a radioteletype system.
Each single-sideband receiver in the system includes at least two detectors or filters, the center frequencies of which are frequency-spaced the same as the frequency-spaced transmitted tones. Scanning or sweep control means are included to vary the center frequencies of the detectors or filters relative to the two frequency-spaced tones while maintaining the difference in frequency between the filters. In a preferred embodiment of the invention, frequency adjustable detectors or filters are used.
The outputs of the detectors or filters are connected to a gate which senses when the two frequency-spaced signals are detected simultaneously, and an output from the gate will terminate the operation of the scanning means. Other circuit means are provided to decode the subsequently broadcasted unique code patterns.
The receiver means may comprise two adjustable filters, each capable of providing an output in response to an input audio tone within its respective frequency band. These filters may be of the phase locked loop type, responsive to a frequency band determined by the values of impedances connected thereto.
The sweep control means comprises means for varying the bandpass center frequency of each of the two adjustable filters in a predetermined number of steps, the bandpass at each step overlapping that of the previous step and next succeeding step. The control means accomplishes bandpass center frequency variation by connecting predetermined ones of a plurality of impedances to the two adjustable filters. Means for connecting these impedances is responsive to a counter which cycles through its succesive states in response to receipt of clock pulses. Application of these clock pulses to the counter is controlled by a NOR gate. The NOR gate discontinues application of clock pulses to the counter upon receipt of a signal from the gate means, indicating that the filter means are properly adjusted.
Accordingly, it is an object of this invention to provide a single-sideband receiver capable of receiving and processing information contained in a series of alternations between two frequencies.
It is a further object of this invention to condition a single-sideband receiver such that a plurality of narrow bandpass filters contained therein will be responsive to a plurality of frequencies.
It is also an object of this invention to provide a single-sideband system in which the receiver is automatically tuned and in which high selectivity is maintained.
Other objects and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic representation of the preferred embodiment;
FIG. 2 is a schematic representation of a portion of the preferred embodiment, showing the two adjustable filters in greater detail;
FIG. 3 is a schematic representation of the frequency sweep control of the preferred embodiment; and
FIG. 4 is a schematic representation of a modification of the frequency sweep control of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1 of the drawings, there is shown a diagrammatic representation of the preferred embodiment of the instant invention. The preferred embodiment comprises a single-sideband system for adjusting a single-sideband receiver to enable it to sense a sequence of alternations between two tones broadcast by a single-sideband transmitter, where the two tones ar initially broadcast simultaneously. An antenna 10 provides signals received to sideband receiver 15.
The receiver 15, including a first and second means for scanning a range of frequencies comprising filters 35 and 40, is selectively responsive to two frequency bands, each of these bands having a center frequency. A decoder 20 is responsive to receiver 15 to decode the sequence of alternations between the two frequency bands. The two frequency bands to which the receiver is responsive may be adjusted under the control of frequency sweep control 25. These frequency bands are varied simultaneously in a cyclic manner such that the center frequencies of the two bands remain a constant frequency differential apart.
A gate 30 is provided to detect the simultaneous reception by receiver 15 of signals in the two frequency bands to which the receiver is then responsive. Gate 30 will sense this simultaneous reception when the receiver 15 is properly conditioned by control 25 and will supply a signal to control 25 to halt further variation of the frequency bands.
Referring now to FIG. 2 of the drawings, a portion of the preferred embodiment of the invention is illustrated in greater detail. Specifically, the HI and LOW filters, 35 and 40, of receiver 15 and their associated circuitry are shown more fully. These filters may typically comprise phase locked loop filters such as integrated circuit NE567 available from Signetics Corp., Sunnyvale, California. The NE567 device, when properly controlled, will act as a filter which provides a zero level signal at its output (pin 8) when an appropriate signal is supplied to its input (pin 3). The bandwidth and center frequency of this device are controlled by connection of appropriately valued impedances to its control terminals. Specifically, the center frequency, f o , is specified by the value of resistance applied between pins 5 and 6 and the value of capacitance connected between pin 6 and ground. The value of capacitance connected between pin 2 and ground determines the bandwidth of the filter.
Filters 35 and 40 receive audio inputs on line 45. The center frequency of HI filter 35 is specified by resistor R 33 and capacitor C 9 and is approximately equal to ##EQU1## Alteration of the center frequency is effected by frequency sweep control 25 by connecting additional impedances between nodes 47 and 49 and between node 49 and ground. Low filter 40 is similarly adjusted by connecting appropriate impedances between nodes 50 and 52, and between node 52 and ground. When both HI filter 35 and LOW filter 40 simultaneously receive signals within their respective bandpass frequencies, a first gate means comprising NOR gate 30 will receive a "low" signal on lines 55 and 56. This will result in a "high" signal being applied to frequency sweep control 25 via line 57. Adjustment of filter frequency will then be halted and decoder 20 will decode the frequency alternations subsequently received.
As mentioned previously, the capacitance connected to pin 2 of the NE567 circuit controls filter bandwidth. Bandwidth is approximately equal to 1070√V i /f o C in % of f o , where V i equals the input voltage and C equals the capacitor attached to pin 2. Thus, in the circuit of FIG. 2, capacitors C 11 and C 12 are determined in this manner.
Capacitors C 13 and C 14 are generally not critical in value. These capacitances set the band edge of low pass filters which attenuate frequencies outside the detection band to eliminate spurious outputs. If these capacitors are too small, frequencies just outside the detection band will switch the output stage of the unit on and off at the beat frequency. If these capacitors are too large, the output stages will be delayed in operation. A typical value for the capacitance connected between pin 1 and ground is twice the capacitance connected between pin 2 and ground. Resistors R 39 and R 40 are load resistors and typically they approximate 20 K.
Turning now to FIG. 3, there is shown in more detail the frequency sweep control 25. A clock 60 provides a series of clock pulses at a predetermined frequency to a second gate means comprising NOR gate G9. As long as no signal is provided on line 61, the output of NOR gate G9 will be an inverted version of the clock pulses. Binary counter 65 will cycle through its counting sequence in response to the clock pulses received from gate G9. Counter 65 in the preferred embodiment of the invention typically will comprise a SN7493 counter available from numerous sources, including Texas Instruments Incorporated, Dallas, Texas. Such a counter will function to cycle through 16 binary states with the A output corresponding to the least significant digit and the D output corresponding to the most significant digit.
A third gate means is responsive to the counter output to connect predetermined ones of a plurality of impedances to the HI and LOW filters to cyclically adjust the frequencies to which these filters are responsive. The impedances comprise capacitors C 1 -C 8 and resistors R 27 -R 32 . The third means includes gates G1-G8, transistors Q 1 -Q 20 , and associated circuitry.
The cyclic operation of counter 65 acts to connect various ones of capacitors C 1 through C 4 between pin 6 of the HI filter and ground and to connect various ones of capacitors C 5 through C 8 between pin 6 of the LOW filter and ground. This connection is controlled by transistors Q 13 through Q 20 . Positive output signals on outputs A through D of counter 65 will result in 2 or more of these transistors being turned on. The center frequencies of HI filter 35 and LOW filter 40 will thus be decreased as the capacitances connected to the filters are increased.
In order that the center frequency of filters 35 and 40 be varied in a linear manner, predetermined ones of a plurality of resistors are selectively connected to the HI and LOW filters. EXCLUSIVE-OR gates G1 through G3 typically comprise integrated circuit SN7486, available from Texas Instruments Incorporated, Dallas, Texas. NAND gates G4, G5, G6 and G8 will typically comprise integrated circuit SN7400, available from Texas Instruments Incorporated. NOR gates G7 and 30 are also available from Texas Instruments Incorporated in the form of circuit SN7402.
Gates G1 through G8 function to provide signals X, Y, and Z to transistors Q 1 , Q 5 , and Q 9 so as to connect resistors R 27 through R 32 in parallel with R 33 and R 34 in such a manner as to linearize the succession of frequencies swept by the filters. The signals X, Y, and Z, which are provided in response to the outputs A through D of counter 65 are illustrated in Table I.
TABLE I______________________________________Count No. Counter 65 A B C D X Y Z______________________________________0 0 0 0 0 0 0 01 1 0 0 0 1 0 02 0 1 0 0 0 1 03 1 1 0 0 1 1 04 0 0 1 0 0 0 15 1 0 1 0 1 0 16 0 1 1 0 1 0 17 1 1 1 0 1 0 18 0 0 0 1 1 0 19 1 0 0 1 1 0 1 10 0 1 0 1 1 0 1 11 1 1 0 1 0 0 1 12 0 0 1 1 1 1 0 13 1 0 1 1 0 1 0 14 0 1 1 1 1 0 0 15 1 1 1 1 0 0 0______________________________________
The gates are arranged so that the X, Y, and Z signals take on values during counter states 8-15 which are the mirror image of the values presented during counter states 0 through 7. A positive X, Y, or Z signal will result in transistors Q 1 , Q 5 , or Q 9 respectively being turned on. This in turn will lower the base voltage of transistors Q 2 , Q 6 , or Q 10 to switch these transistors on and thus provide positive signals to the gates of uni-junction transistors Q 3 , Q 7 , Q 11 , Q 4 , Q 8 , or Q 12 . Various ones of the resistors R 27 through R 32 are connected across pins 5 and 6 of the filters in this manner to linearize successive filter center frequencies.
A clock frequency is provided by clock 60 such that the counter will cycle through its 16 possible states five times during the period of time in which the two simultaneous tones are broadcast. If during one of these cycles the filters 35 and 40 simultaneously detect input signals of appropriate frequency, one shot multivibrator 70 will be activated by NOR gate 30. The one shot will thus provide a signal to NOR gate G9 and preclude further transmission of clock pulses to counter 65. This will cause counter 65 to cease its cyclic state change with the result that the center frequencies of the HI and LOW filters will be set to detect subsequent frequency alternations. The one shot multivibrator 70 will provide an output on line 61 sufficient in duration to preclude the center frequency of the filters from being changed during a period of time necessary to receive an entire message.
As shown in FIG. 4, refinement is possible whereby the one shot 70', corresponding to one shot 70 shown in FIG. 3, is a retriggerable multivibrator and retriggering is controlled by decoder 20. In such a refinement the decoder would provide retrigger pulses of sufficient frequency to maintain an output on line 61 as long as the decoder was receiving valid data. Thus if two extraneous signals were simultaneously received by the HI and LOW filters, the receiver would not be disabled from cyclic scanning for a significant time period. The decoder 20 would simply not provide pulses to one shot 70 when valid data failed to follow receipt of the two tones and, as a result, gate G9 would be quickly enabled to pass clock pulses to counter 65.
Below is a table listing typical component values when transmitted frequencies are 1300 Hz and 1820 Hz for the preferred embodiment of the instant invention
ELEMENT VALUE______________________________________R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, 1 K ohmsR.sub.7, R.sub.8, R.sub.9, R.sub.10, R.sub.11R.sub.12, R.sub.13, R.sub.14 10 K ohmsR.sub.15, R.sub.16, R.sub.17 2.2 K ohmsR.sub.18, R.sub.19, R.sub.20 100 K ohmsR.sub.21, R.sub.22, R.sub.23, R.sub.24, R.sub.25, R.sub.26 3.3 K ohmsR.sub.27, R.sub.28 180 K ohmsR.sub.29, R.sub.30 300 K ohmsR.sub.31, R.sub.32 510 K ohmsR.sub.33 6.684 K ohmsR.sub.34 13.931 K ohmsC.sub.1, C.sub.5 .00285 μfd.C.sub.2, C.sub.6 .0057 μfd.C.sub.3, C.sub.7 .0114 μfd.C.sub.4, C.sub.8 .0228 μfd.C.sub.9 .0748 μfd.C.sub.10 .047 μfd.C.sub.15, C.sub.16, C.sub.17, C.sub.18 .1 μfd.HI Filter Synetrics NE-567LOW Filter Synetrics NE-567COUNTER SN7493G1, G2, G3 SN7486G4, G5, G6, G8 SN7400G7, G9, 30 SN7402______________________________________
While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention. | A single-sideband radiotelephone system includes a single-sideband transmitter which initially broadcasts two frequency-spaced tones simultaneously for a predetermined time interval, and thereafter broadcasts the two tones alternately in a unique code pattern to access a predetermined receiver. Each single-sideband receiver in the system includes a pair of detectors each having a narrow bandpass, the center frequencies of which are spaced apart by the difference in frequency of the transmitted tones. The center frequencies of the detectors are simultaneously varied relative to the initial two-tone broadcast while maintaining the frequency differential therebetween; and simultaneous detection of both tones will terminate the frequency varying mode of operation. The subsequently transmitted unique code pattern is then sensed by the detectors, the code pattern decoded, and the selected receiver is enabled to receive any subsequently broadcasted information. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to an engine/transmission system and more specifically to such a system wherein the engine is supercharged using either one, or both of a supercharger and a turbocharger.
2. Description of the Prior Art
JP-A-63-17131 and JP-A-61-113526 disclose examples of arrangements wherein engines are combined with automatic transmissions. However, in these arrangements the engine torque and the transmission shifting are controlled independently of one another. As a result, during transmission shifting, if engine torque control is either initiated or stopped, a relatively large shift shock tends to be produced and leads to the situation wherein erratic shift shocks tend to occur.
In order to overcome this problem it was proposed to provide communication between the transmission and engine torque control units and to limit the initiation and termination of engine torque control during transmission shifting.
However, this arrangement suffers from the drawback that this arrangement controls only the ignition timing or air-fuel ratio and ignores the effect of a supercharging device such as an exhaust gas driven turbocharger or mechanically driven supercharger. Thus, during upshifts which are induced under minimum engine load conditions (non-depressed accelerator pedal conditions) still a wide variation in shift shock are encountered.
That is to say, in an engine/transmission system wherein the engine is supercharged, the amount of shift shock will vary depending on the presence or absence of supercharge pressure at the time an upshift is produced under minimal engine load. By way of example, even in the case wherein the induction system is synchronously controlled with the other torque control measures, the actual amount of air which is supplied to the engine varies. That is to say, the rate at which the engine speed drops (dashpot rate) is effected by the supercharge pressure in a manner wherein under some conditions it is rapid and slow under others. This variation in engine speed is basic cause of the shift shock generation.
It should be noted that depending on the presence or absence of supercharge pressure, until the engine speed reaches a predetermined level (e.g. 3000 rpm) the supercharge produces relatively little effect. However, after this level is exceeded the effect of the supercharge pressure increases dramatically. For example, in the case where the external load on the engine is high and the accelerator pedal depression changes from a state wherein a high supercharge pressure is induced in the induction manifold, to a fully released state, even though the throttle valve assumes a fully closed state, the supercharge pressure tends to remain. On the other hand, if the accelerator pedal moves from a half-throttle position to a fully released one while the engine load is low and the supercharging level is low, the induction pressure soon becomes negative.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a control system which alleviates sporadic shift shock when a transmission associated with a supercharged internal combustion engine undergoes an upshift while the engine is operating under minimal load (e.g. with the accelerator pedal non-depressed).
In brief, the above object is achieved by an arrangement wherein the supercharge pressure is monitored and if the pressure is above a predetermined limit during a minimal load upshift, the pressure generated by the supercharging device is reduced and at the same time an idle control system feed-back meters the amount of air supplied to the engine so that the rate at which the engine speed reduces is maintained essentially constant irrespective of the initial supercharge pressure.
More specifically, a first aspect of the present invention comes in a system which includes a internal combustion engine and an automatic transmission and which features: means responsive to a supercharge pressure control signal for supplying a super charge pressure to the internal combustion engine; a supercharge pressure sensor; an accelerator pedal depression sensor; means for producing a transmission shift control signal; and means for producing a supercharge pressure reduction control signal when an upshift is induced under conditions wherein the accelerator pedal is not depressed and the supercharge pressure is above a predetermined level.
A second aspect of the present invention comes in a vehicular system which features: a supercharger operatively connected with an internal combustion engine for supplying air under pressure to the engine; a supercharge pressure sensor; an engine load sensor for producing a signal indicative of the engine operating under minimal load; an automatic transmission operatively connected with the engine; means for monitoring the operation of the transmission and for indicating the transmission undergoing a shift; and supercharge pressure control means responsive to the supercharge pressure sensor, the engine load sensor and the indication from the transmission monitoring means that the transmission is operating under minimum engine load and undergoing an upshift, for reducing the supercharge pressure in the event that the supercharge pressure is above a predetermined level while the transmission is shifting.
A third aspect of the present invention comes in a vehicular system which features: supercharger means operatively connected with an internal combustion engine for supplying air under pressure to and induction system of the engine; supercharger control means for varying the amount of supercharge pressure produced by the supercharger; a supercharge pressure sensor, for sensing the level of supercharge pressure in the engine induction system; an engine load sensor for producing a signal indicative of the engine operating under minimal load; an automatic transmission operatively connected with the engine; means for monitoring the operation of the transmission and for indicating the transmission undergoing an upshift; idle control means for controlling the amount of air which is supplied to the engine while the engine is operating under minimal load conditions; and supercharge pressure control means responsive to the supercharge pressure sensor, the engine load sensor and the indication from the transmission monitoring means that the transmission is operating under minimum engine load and undergoing an upshift, for reducing the amount of supercharge pressure produced by the supercharger and for controlling the amount of air which is supplied to the engine so that the rate at which the engine speed reduces is maintained at essentially the same value irrespective of the level from which the supercharge pressure is reduced when the transmission is upshifting under minimal engine load.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing the conceptual arrangement of the present invention;
FIG. 2 is a schematic view showing an engine system to which the present invention is applied;
FIG. 3 is a shift schedule according to which the transmission shown in FIG. 1 is controlled;
FIG. 4 is a flow chart depicting the operations which characterize a control routine according to the present invention; and
FIGS. 5 and 6 are timing charts depicting the supercharge pressure control which is achieved with the present invention and that provided by the the prior art, respectively.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a system which basically comprises a turbocharged engine 1 operatively connected with an automatic transmission 10. The system includes an idle detection switch 2, a vehicle speed sensor 3, an engine speed sensor 4, a supercharge pressure sensor 5 and miscellaneous other switches and sensors generally denoted by black box 6. These sensors are operatively connected with an ECCS type engine control unit 7 in a manner wherein suitable data required to determine the nature of a supercharge pressure control signal which is applied to a supercharge pressure control solenoid 8 and an induction control signal which is applied to an AAC valve 9 which forms part of an idle control system.
An accelerator pedal depression sensor 11 along with suitable other switches generally denoted by element 12 are operatively connected with an automatic transmission (A/T) control unit 13 and is supplied with data input therefrom. As will noted, the output of the vehicle speed sensor 3 is also supplied to the A/T control unit 13. The A/T control unit 13 is arranged to output a control signal or signals to one or more transmission control solenoids generally denoted by numeral 14. The A/T control unit includes a microprocessor or the like type of circuit arrangement which controls the shifting of the transmission in accordance with a shift schedule of the nature shown in FIG. 3. As will be appreciated, this schedule is recorded in terms of vehicle speed and engine load as indicated by the amount of accelerator pedal depression.
The ECCS control unit 7 and the A/T control unit 13 include IC data transfer circuits 7a and 13a which are placed in communication with one another by transmission lines 20 and 21. This arrangement enables the two circuits to be informed of the given operations (viz., operations which are pertinent to shift shock attenuation) being performed by the other on a real time basis.
In the control network established by the above arrangement, data indicating if the transmission is undergoing a shift, the gear position in which the transmission is operating and/or the position to which the shift is being made, and if the shift is being made with the accelerator in a non-depressed condition, is transferred from IC 13a to IC 7a.
Depending on the transmission operating conditions it is determined if the instant supercharge pressure level is above a predetermined level or not. In the event that the instant supercharge or boost pressure is found to be too high, the signal which is applied to the waste gate control solenoid 8 is modified in a manner which increases the amount of exhaust gases which are permitted to by-pass the turbocharger turbine and thus reduce the amount of energy with which the turbocharger compressor is driven.
FIG. 2 shows an example of a turbocharged engine and the manner in which the ECCS control unit is operatively connected therewith. As shown, a turbocharger 32 is operatively arranged with induction and exhaust conduits 30 and 31, in a conventional manner. An intercooler 33 is disposed in the induction conduit at a location downstream of the turbocharger compressor. A control pressure conduit 34 leads from the induction conduit at a location downstream of the intercooler, to a pneumatically operated waste gate servo motor or so called swing valve 35. The waste gate control solenoid 8 is arranged to control the amount of pressure which is permitted to vent from the control pressure conduit 34 into a by-pass conduit 37 which leads back to the induction conduit and communicates therewith at a location upstream of the turbocharger compressor. In this instance, when the solenoid 8 is energized (ON) communication between the conduits 34 and 37 is cut-off and the amount pressure which is supplied to the servo chamber of the swing valve 35 is maximized, the waste gate 36 is induced to close and the amount of exhaust gas which is permitted to by-pass the turbocharger turbine is minimized. On the other hand, when the solenoid valve is OFF the pressure which is supplied to the servo chamber of the swing valve 35 is reduced, the waste gate 36 is permitted to open and the amount of exhaust gases which are permitted to by-pass the turbine is increased.
The AAC valve 9 is arranged in the induction system in a manner to control the amount of induction air which is permitted to pass through a by-pass conduit 38 and by-pass a throttle valve 37. The signal which is applied to the AAC valve 9 switches between high and low levels (ON/OFF) at a predetermined frequency. By increasing the period for which the signal assumes the high (ON) level, the amount of air which is permitted to by-pass the throttle valve is increased.
The operation of the above arrangement will be discused with reference to the flow chart shown in FIG. 4. This flow chart depicts a control routine which is run in the ECCS control unit 7 and which is used to control the supercharge pressure and idling speed.
At step 1001 signals which are indicative of the transmission undergoing a shift, the status of the idle switch, the level of the supercharge pressure and the engine speed are read in. At step 1002 it is determined if the "shift signal" as will be referred to, exhibits a high level (transmission is undergoing a shift) or not. In the event of an affirmative outcome the routine goes to step 1003 wherein it is determined if the idle switch signal is indicative of the throttle valve being fully closed or not.
In the event that the throttle valve is indicated as being fully closed, the routine proceeds to step 1004 wherein it is determined if the instant supercharge pressure (Pc) is indicated as being above a predetermined level (Po) or not.
In response to a finding that Pv<Po and in response to negative outcomes in steps 1002 and 1003, the routine goes to step 1005 wherein a command to close the waste gate is issued. This command is such as to induce the supercharge pressure control solenoid 8 to assume an ON (energized) condition, and to result in the swing valve 35 closing the waste gate 36. On the other hand, if the outcome of step 1004 is such as to indicate that Pc≧Po the routine goes to step 1006 wherein a command to set the supercharge pressure control solenoid 8 to OFF is issued. This of course induces the swing valve 35 to open the waste gate 36.
Step 1007 follows either of steps 1005 and 1006. In this step feedback control of the engine idling speed is executed in a manner which limits the degree to which the engine speed is permitted to reduce. This control is accomplished by controlling the ACC valve 9 and the amount of air which is permitted to by-pass the closed throttle valve 37. As such feedback control of the engine speed and how it is accomplished will be self-evident to those skilled in automotive engineering, detailed disclosure of the same will be omitted for the sake of brevity.
An example of the control which is implemented during a minimum engine load upshift is given in timing chart form in FIG. 5. In the case an upshift which takes place under the conditions wherein a half-throttle condition changes to a fully released accelerator pedal one and the supercharge pressure disappears, given that the shifting and idling conditions are satisfied while the supercharge pressure is still less than the predetermined limit Po, the waste gate remains closed. However, at this time the amount of air which is permitted to be supplied to the engine is controlled in the same manner as in the case of a non-supercharged engine and the rate at which the the engine speed is permitted to reduce is limited to a predetermined value and the upshift (e.g. a 1-2 upshift) is timed to occur when the engine speed has reduced to a given low level.
In the case of an upshift which occurs after a full throttle condition has changed to a fully released or non-depressed accelerator pedal state, the shifting and idle requirements will be satisfied and the waste gate will be opened due to the elevated supercharge pressure.
As a result, from the time the waste gate opens the supercharge pressure exhibits a rapid decrease and, due to the idle control system which determines the amount of air which is permitted to by-pass the closed throttle valve 37 via by-pass conduit 38, the rate at which the engine speed is permitted to decrease is limited to almost exactly the same value as in the case wherein the supercharge pressure was absent, and the upshift (e.g. the 1-2 upshift) occurs just as the engine speed has reduced to the above mentioned given low level.
With the above control it is possible to realize the following advantages with supercharged engine/transmission systems.
1. When a minimum engine load upshift occurs as the supercharge pressure is sensed and its presence or absence determined, it is possible to control the induction pressure level in a manner wherein the difference in the amount of air which is supplied to the engine in the presence and absence of supercharge pressure, can be reduced to a small value and random shift shock generation prevented.
2. When a minimum engine load upshift takes place, irrespective of the supercharge pressure level which prevailed immediately before the shift, at the time the shift initiates the induction pressure can be controlled so that almost no difference occurs. It is also possible for the rate at which the engine speed reduces to be simultaneously controlled to essentially the same value via controlling the amount of air which is permitted to pass through the idle control system. This results in the timing with which the engine speed reaches a given value in the absence of supercharge pressure being essentially the same timing as in the case wherein a high supercharge pressure was initially present and enables very effective attenuation of the shift shock.
It will be appreciated that the present invention is not limited to the disclosed embodiment and that various variations are possible without departing from the scope of the same.
For example, even though the turbocharger is disclosed as having a waste gate for by-passing exhaust gases about the turbine thereof, the use of variable capacity devices which enable the amount of supercharge pressure to be controlled without the need of waste gating and the like can be envisaged.
Further, as supercharge pressure and induction air control systems are combined, while the supercharge pressure control is disclosed as being basically of the ON/OFF type, it is possible determined the amount of movement which lead to the accelerator pedal assume the non-depressed state and vary the degree to which the supercharge pressure is reduced, based on the same. | In order to alleviate sporadic shift shock when a transmission associated with a supercharged internal combustion engine undergoes an upshift while the engine is operating under minimal load (e.g. with the accelerator pedal non-depressed) the supercharge pressure is monitored and if the pressure is above a predetermined limit during a minimal load upshift, the pressure generated by the supercharging device is reduced and at the same time an idle control system feed-back meters the amount of air supplied to the engine so that the rate at which the engine speed reduces is maintained essentially constant irrespective of the initial supercharge pressure. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to air or gas sealing arrangements for rotating cylinders such as rotary kilns or the like, whereby the ingress and egress of diluent and contaminating gaseous fluids at the ends of the rotating cylinder are significantly reduced by the sealing arrangement.
The sealing arrangement of the present invention is an improvement over the sealing arrangement shown by U.S. Pat. No. 3,042,389 issued to David H. Gieskieng on July 3, 1962 and that shown by U.S. Pat. No. 4,209,175 to Robert M. Bliemeister dated June 24, 1980.
2. Description of the Prior Art
It is known in the prior art as taught by the aforementioned U.S. Pat. No. 3,042,389 of David H. Gieskieng to provide a self-counterweighted sealing ring for sealing the annular clearance space between a rotating cylinder such as a rotary kiln and a stationary structure such as a feed housing at one end of the rotating kiln or a firing hood at the opposite end of the rotating kiln, with respect to which the rotary cylinder rotates. The self-counterweighted annular seal of the aforementioned U.S. Pat. No. 3,042,389 has a self-counterweighted construction such that the center of gravity of the annular seal lies in a plane normal to the axis of rotation of the rotary cylinder which is axially displaced from the plane, also normal to the axis of rotation of the cylinder, in which the annular sealing ring contacts the outer surface of the kiln. This construction results in the creation of a force moment arm which causes the annular sealing ring to be continuously tilted into sealing engagement with the associated stationary structure, such as the stationary feed end housing at one end or the stationary firing hood at the opposite end of the rotating kiln. The seal construction just described substantially prevents leakage of gaseous fluid through the annular clearance space between the rotating cylinder and the stationary structures at the respective opposite ends of the rotating cylinder.
It is also known in the prior art as taught by the aforementioned U.S. Pat. No. 4,209,175 to Robert M. Bliemeister to provide an articulated seal for rotating cylinders of the type shown by the aforementioned U.S. Pat. No. 3,042,389 consisting of a plurality of circumferentially extending seal segments which are pivotally jointed to permit articulation of the joined segments in a plane perpendicular to the axis of the rotating cylinder to accommodate "out-of-round" portions of the circumference of the cylinder during relative rotary movement between the annular seal and the rotating cylinder.
As disclosed in the aforementioned U.S. Pat. No. 4,209,175, the seal hangs with loose contact on the upper surface of the rotating cylinder and hangs with a small clearance with respect to the lower surface of the rotating cylinder. This clearance is needed to permit the seal to walk along the shell of the rotating cylinder.
While a small clearance is needed to permit the seal to walk along the shell of the rotating cylinder, it is desirable not to allow the clearance to be any larger than necessary since a large clearance interfers with effective sealing.
In the past, the seal was fabricated and designed to allow for a small clearance. However, several problems have arisen. Since the cylinder normally operates at elevated temperatures, the kiln cylinder is prone to thermal expansion. Additionally, the seal, in contact with the cylinder surface, is also prone to thermal expansion. While the amount of thermal expansion of the seal and cylinder is taken into account in designing the seal dimensions to provide for an adequate clearance, the thermal expansion cannot always be predicted with adequate precision. Consequently, seals may be fabricated with too large a clearance, reducing seal efficiency, or with too small a clearance, inhibiting the ability of the seal to walk along the cylinder.
STATEMENT OF THE INVENTION
It is an object of the invention to provide in an articulated seal for rotating cylinders of the type shown by the aforementioned U.S. Pat. No. 4,209,175 a plurality of eccentric pin pivot joints to permit field adjustment of articulated seal segments to provide an acceptable clearance between the seal and the rotating cylinder to permit walking of the seal while maintaining an acceptable seal.
In achievement of these objectives, there is provided in accordance with the invention, a seal for use in sealing an annular opening between a stationary member and a rotating cylinder which is telescopically arranged in said stationary member, said seal comprising an annular ring member circumscribing said cylinder adjacent said stationary member and closing said annular opening, wherein the improvement comprises having said annular ring member formed of a plurality of circumferentially extending ring segments, with circumferentially contiguous segments being pivotally connected to each other whereby contiguous segments may articulate with respect to each other to accommodate "out-of-round" places on the outer periphery of said rotating cylinder.
The pivotal connections comprise a tongue-like portion of a seal segment extending in overlying relation to an adjacent seal segment. A tongue-like portion of the adjacent seal segment affixed to a spacer member of the adjacent segment extends in overlying relation to the tongue-like portion of the seal segment whereby each pivotal connection comprises a portion of a seal segment engaged between two portions of an adjacent seal segment. An eccentric pin is provided extending through the seal segments at each pivotal connection. The pin contains an eccentric central portion having a central axis displaced from the central axis of the remainder of the pin. Rotation of the pin within the pivotal connection permits adjustment of the distance between two adjacent segments. Rotation of all pins permits adjustment of the circumference of the articulated seal until a desired gap between seal and rotating cylinder is attained. Once the gap is attained, a lock bar is affixed to each pivotal connection preventing unwanted rotation of the pin.
Further objects and advantages of the invention will become apparent from the following description taken in conjunction with the accompanying drawings:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation view partially in section of a rotary kiln embodying the present invention;
FIG. 2 is a sectional view taken along line II--II of FIG. 1 to show the annular sealing ring contiguous the feed end of the kiln, with details of the kiln being omitted for purposes of clarity;
FIG. 3 is an enlarged detail view, somewhat exaggerated for purposes of clarity, showing the relationship of the annular sealing ring 70 of FIG. 1 to the rotary kiln and to the stationary bearing collar at the feed end of the kiln, with the angle of inclination of the kiln being exaggerated in order to more clearly show the relationship of the various members;
FIG. 4 is an enlarged fragmentary section taken along line IV--IV of FIG. 2;
FIG. 5 is an enlarged fragmentary section taken along line V--V of FIG. 8;
FIG. 6 is an enlarged detailed view of one of the segments of the annular sealing ring of the type shown in FIG. 2, and showing the pivotal connection of the segment to an adjacent segment which is the subject of this invention;
FIG. 7 is a fragmentary edge view of the sealing ring segments of FIG. 6;
FIG. 8 is a sectional view taken along line VIII--VIII of FIG. 1 to show the annular sealing ring contiguous the firing hood end of the kiln, with details of the kiln being omitted for purposes of clarity; and
FIG. 9 is a view of an eccentric pin removed from the pivotal connection.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, and more particularly to FIG. 1, there is shown a rotary kiln generally indicated at 10 which inclines slightly downwardly from a feed end housing 12 to a firing hood 14 to assist in the movement of material through the kiln from the feed end 12 to the firing hood 14. Kiln 10 comprises a tubular or cylindrical shell 16 having an internal lining 18 formed of a suitable refractory material, for example, refractory bricks. A plurality of riding rings 20, only one is shown in the drawings, is disposed circumferentially about shell 16 and is supported on suitable carrying rollers 22. Suitable drive means (not shown) are provided, for example, a motor driven ring gear circumferentially mounted about shell 16 for rotating kiln shell 16 about its longitudinal axis. Such a drive means is shown, for example, by U.S. Pat. No. 3,511,093, issued to Eugene B. Cook on May 12, 1970.
At one end of the tubular shell 16, an annular end plate 24 is secured and defines a substantially circular feed opening 26 through which a feed material, either dry or as a slurry, is fed from a chute 28 interconnecting kiln chamber 30 and a suitable storage facility (not shown).
Another annular end plate 32 is secured to the opposite end of shell 16 and defines a substantially circular discharge opening 33 through which the material, after treatment in the kiln, is discharged to conveyors, coolers, or the like, depending upon the type of processing required for the material being treated.
At the feed end of the kiln, chute 28 is supported within the feed end housing 12 which has a front wall 34 in which is defined an opening 36. Opening 36 preferably corresponds generally to the shape of cylindrical shell 16 but is intentionally larger to provide for the telescopic arrangement of kiln shell 16 within housing 12 as shown. The dimensional difference between opening 36 and the outer diameter of shell 16 defines an annulus 38 which permits slight distortion of kiln shell 16 during operation without binding between kiln shell 16 and feed housing 12. The peripheral surface 37 in wall 34 which defines opening 36 in wall 34 is provided with a collar member generally indicated at 40 and best seen in FIG. 4, including an annular portion 42 which lines the peripheral surface 37 in front wall 34 and is concentric about a horizontal axis, the annular portion 42 extending beyond the inner face of wall portion 34 and terminating in a peripherally extending flange portion 44 which lies in a plane perpendicular to the axis of rotation of kiln 16, and thus, lies in a plane which is slightly inclined relative to front wall 34 of feed housing 12. A circumferentially extending wear plate 45 is suitably secured to the axially inner surface of flange 44.
Instead of having annular portion 42 of collar member 40 line annular peripheral surface 37 of front wall 34, as hereinbefore described and shown in FIGS. 1 and 4, annular portion 42 could instead be secured as by welding directly to the axially inner surface of front wall 34, with annular portion 42 not extending inside wall 34. Also, instead of having front wall 34 perpendicular to the horizontal axis as shown in FIGS. 1 and 4, front wall 34 instead could be normal to the kiln axis of rotation, in which case, collar 40 could be eliminated and annular seal 70 could bear directly against the surface of wall 34 or against a wear plate similar to wear plate 45 which might be secured to wall 34.
Adjacent the discharge end of kiln 10, firing hood 14 comprises a housing 50 having a lining 52 formed of a suitable refractory material. Firing hood 14 contains a conventional burner 54 through which is fed the mixture of fuel and oxygen designed for the specific process to be employed in the kiln.
Firing hood housing 50 includes a front wall 56 having defined therein an opening 58 (similar to opening 36 in feed end housing wall 34) which circumscribes the outer periphery of kiln shell 16 to define an annulus 60 therebetween. Wall 56 is normal to the axis of rotation of kiln 10. The portion of hood front wall 56 extending radially away from opening 58 defines a bearing surface for annular sealing ring 72. Due to the very high temperature conditions at the contiguous firing hood 14, it is generally not advisable to provide firing hood 14 with a separate bearing collar member such as the collar member 40 carried by feed end housing 12 and having the bearing flange 44 and wear plate 45.
As shown in FIG. 1, annular sealing rings, each respectively generally indicated at 70 and 72, are provided in circumscribing relationship to kiln shell 16 for respectively closing annulus 38 between kiln cylinder 16 and feed end housing 12 and for closing annulus 60 between kiln cylinder 16 and firing hood 14.
Sealing ring 70 (see FIGS. 1, 2 and 4) comprises an axially extending annular inner surface 74 having a cylinder-engaging portion 75 which seats or hangs with loose contact on the upper surface of kiln shell 16 but with the annular surface 74 of sealing ring 70 being spaced below and having a small clearance, such as at 105, with respect to the outer peripheral surface of kiln shell 16 at the lower surface of kiln shell 16. Annular sealing ring 70 also includes an annular sealing portion 78, which includes a sealing surface 78A, extending radially outwardly from inner surface 74. Annular sealing portion 78 and sealing surface 78A thereof serve to close annulus 38 between front wall 34 of feed end housing 12 and the outer periphery of kiln shell 16. Annular sealing ring 70 also includes a weighting portion 80 in the form of an annular member which is fixed as by welding to a radially intermediate portion of annular sealing portion 78 of seal member 70. Weighting portion 80 extends away from sealing portion 78 in a direction which is substantially parallel to the axis of rotation of kiln cylinder 16, whereby to cause the center of gravity CG (FIG. 3) of sealing ring 70 to be axially offset from the geometric center of annular sealing portion 78. Weighting portion 80 coacts with cylinder engaging portion 75 of seal member 70 to define a moment arm 82 therewith.
Another form of annular sealing ring 72 is shown in circumscribing relation of kiln cylinder 16 at the contiguous firing hood 14. Any of the various forms of annular sealing rings described in this specification could be interchangeably used at either end of the kiln cylinder 16.
Sealing ring 72, as seen in FIGS. 1, 5 and 8, comprises an axially extending annular inner surface 88 having a cylinder engaging portion 107 which hangs with loose contact on the upper surface of kiln cylinder 16 in the same manner as described in connection with annular sealing ring 70. Annular inner surface 88 has a small clearance, such as at 106, with respect to the lower surface of kiln shell 16. Sealing ring 72 also comprises an annular sealing portion 92 which extends radially from inner surface 88 of sealing ring 72 and engages bearing surface 56 of firing hood 14 to close annulus 60. Ring 72 also includes a weighting portion generally indicated at 94 and comprising a plurality of independent discrete weight members 96 secured to annular sealing portion 92 in peripherally spaced relation to each other to form an integral structure with annular sealing portion 92 in which the center of gravity of sealing ring 72 is axially offset from the geometric center of annular sealing portion 92. The symmetrically disposed discrete weight means 96 may be secured to annular sealing portion 92, in any suitable manner, such as by means of a threaded engagement as shown at 100 in FIG. 5; or, alternatively, weight means 96 may be welded to annular sealing portion 92.
Still another embodiment of annular sealing ring which might be used would be similar to that shown in FIG. 5 of the aforementioned U.S. Pat. No. 3,042,389 in which the annular weighting portion extends from the radially outer end of the annular sealing member rather than from the radially intermediate portion of the annular sealing member.
Any of the various sealing rings described herein should have sufficient clearance with respect to the outer diameter of kiln shell 16 to permit the seal to "walk" along the kiln shell into sealing engagement with the corresponding annulus 38 or 60.
In order to permit the annular sealing rings 70, 72 to deform with an "out-of-round" kiln shell 16, each of the annular sealing rings such as 70 and 72 is formed in a plurality of pivotally connected segments which permit articulation of the pivotally joined segments of the sealing ring in a plane perpendicular to the axis of rotation of the kiln. The annular sealing ring should include at least three pivotally connected circumferential segments, although the embodiments of the invention shown in the drawings each includes four pivotally connected segments, each of which extends circumferentially for substantially 90°. This articulated construction of the annular seal members permits the inside diameter of the sealing ring to deform to substantially conform to a misshapen or "out-of-round" shell 16 and, at the same time, permits the annular sealing ring to remain free to move axially on the shell. Such capability of axial movement of the annular sealing ring is important during the dynamics of kiln rotation to permit each annular seal to have any axial movement necessary to accommodate itself into proper sealing relation with the corresponding annulus which it seals, such as the annulus 38 which is closed by annular seal 70 in FIG. 1 and the annulus 60 which is closed by annular seal 72 of FIG. 1, all in accordance with the teachings of the aforementioned U.S. Pat. No. 4,209,175.
Referring to FIG. 2, it can be seen the annular seal generally indicated at 70 is made up of a plurality of circumferential segments respectively indicated at 70A, 70B, 70C and 70D, each of which extends substantially 90° of the periphery of kiln cylinder 16.
Referring to FIGS. 2, 6 and 7, which show the pivotal connection between two segments 70A and 70B of annular sealing ring 70, it can be seen segment 70A is provided in the region of its pivotal connection to segment 70B with a tongue-like portion 83A which is suitably secured to the axially inner surface of sealing ring portion 78 of segment 70A (with respect to the installed position of seal 70 shown in FIG. 1), tongue-like portion 83A extending in overlapping relation to sealing ring portion 78 of the contiguous segment 70B. Seal segment 70B is provided with a cooperating tongue portion 85B which is suitably secured to a spacer member 87B, which in turn is fixed to the axially inner surface of annular sealing portion 78 of segment 70B. Tongue portion 85B on sealing ring segment 70B is so positioned by means of spacer member 87B that the tongue portion 85B, overlies with respect to the view of FIGS. 2 and 7, the cooperating tongue portion 83A of seal segment 70A. An eccentric pin member 89 is received in suitable passages in tongue portion 85B of seal segment 70B, through tongue portion 83A of the seal segment 70A and through sealing portion 78 of segment 70B whereby to pivotally secure the two seal segments 70A, 70B together whereby segments 70A, 70B may articulate with respect to each other as required by variations in the outer diameter of kiln cylinder shell 16 during the rotation of the kiln, as might be caused by a misshapen or "out-of-round" shell.
As shown in FIGS. 7 and 9, eccentric pin 89 comprises three generally cylindrical portions including a base portion 89A, a body portion 89B, and neck portion 89C. Base portion 89A, body portion 89B and neck portion 89C are arranged in overlying relation with base portion 89A and neck portion 89C sharing a common central axis X--X. Body portion 89B, arranged between base portion 89A and neck portion 89C, has central axis Y--Y disposed parallel to axis X--X and disposed away therefrom a suitable distance (e.g., 1/4 inch).
As shown in FIG. 7, embodied in the pivotal connection, base portion 89A occupies a suitable passage in sealing ring portion 78 of seal segment 70B, and body portion 89B occupies a suitable passage in tongue portion 83A of seal segment 70A, and neck portion 89C extends through a suitable passage in tongue portion 85B of seal segment 70B. A lock notch 100 is provided in neck portion 89C of eccentric pin 89 above tongue portion 85B. Lock notch 100 extends along a line generally perpendicular to both axis X--X and axis Y--Y with a base 101 of lock notch 100 flush with tongue portion 85B. A lock bar 102 is provided positioned within lock notch 100 and suitably secured to tongue portion 85B such as by weld as shown at 103. Before securing lock bar 102, eccentric pin 89 may be rotated 180° about axis X--X thereby drawing the two seal segments 70A and 70B closer together. Eccentric pin 89 may be rotated less than 180° about axis X--X to provide for incremental adjustment of seal segments 70A, but such an adjustment would result in a failure of inner surfaces 88A and 88B to align in a smooth circumferential arc. After securing lock bar 102, the distance between seal segments 70A and 70B can be adjusted by removing lock bar 102 (such as by breaking weld 103) and rotating eccentric pin 89 as described above.
In operation of the rotary kiln 10 of FIG. 1, the counterweighted construction of sealing rings 70 and 72 causes sealing ring 70 to "walk" into sealing engagement with bearing surface 45 at the feed end of the kiln, and causes sealing ring 72 to "walk" into engagement with bearing surface 56 of firing hood 14 at the discharge end of the kiln to substantially prevent ingress and engress of gases through the annular openings 38 and 60, all in the manner described in the aforementioned U.S. Pat. No. 3,042,889.
Also, sealing rings 70 and 72 described hereinbefore and shown in the drawings, provide a pivotal connection between contiguous circumferential segments of the annular sealing ring to permit the sealing ring to have an articulating movement to accommodate the sealing ring to "out-of-round" spots on the outer surface of the rotating cylinder, such as kiln shell 16, all in accordance with the techings of U.S. Pat. No. 4,209,175.
At the installation of sealing rings 70 and 72, or at any later time, gaps 105 and 106 may be adjusted in size by rotating all or a select number of eccentric pins 89 to increase the gaps 105, 106 to facilitate walking of seals 70, 72 or decrease gaps 105, 106 to increase seal efficiency.
Each of the annular seals hereinbefore described should preferably be rigid in a plane parallel to the surface against which it seals, such as flange 44 and wear plate 45 at the feed end of kiln 10, or front wall 56 at the discharge end of the kiln.
While the annular seal of the invention has been described as used with a rotary kiln, it can also be used in connection with rotating cylinders used as rotary coolers, rotary dryers or the like.
From the foregoing detailed description of the invention, it has been shown how the objects of the invention have been obtained in a preferred manner. However, modifications and equivalents of the disclosed concepts, such as readily occur to those skilled in the art, are intended to be included within the scope of this invention. | A seal for use in sealing an annular opening between a stationary member and a rotating cylinder telescopically arranged in the stationary member, the seal comprising an annular ring member circumscribing the cylinder adjacent the stationary member and closing the annular opening. The seal comprises weighting means extending axially away from a backside of the ring member to provide a counterweighting effect which causes a tilting of the ring member, whereby said tilting, and the rotation of the cylinder, moves the ring member into engagement with the stationary member to substantially seal the annular opening, all in accordance with the teaching of U.S. Pat. No. 3,042,389. The annular ring member is divided into a plurality of circumferentially extending segments in which adjacent segments are pivotally connected to each other to permit articulation of the segments to accommodate "out-of-round" portions of the rotating cylinder, all in accordance with the teachings of U.S. Pat. No. 4,209,175. In accordance with the present invention, an eccentric pin is provided pivotally connecting contiguous segments permitting adjustment of the seal circumference to facilitate walking of the seal about the cylinder and increase seal efficiencies as required during the installation or operation of the seal. | 8 |
FIELD OF INVENTION
[0001] The field is the copolymerization of non-polar C 4 -C 30 ethylenically unsaturated aliphatic olefins with monomers containing electron withdrawing groups such as acrylates. The copolymerization rates of such polar acrylates and nonpolar olefin monomers are modified, by the use of a Brönsted or Lewis acid that is believed to complex either the polar monomer or the repeating unit from the polar monomer when it is the free radical chain end. The polymerization media is preferably aqueous, which is a non-conventional media for Brönsted and Lewis acid catalyzed polymerizations. The resulting copolymer is a stable emulsion or dispersion of polymer particles in aqueous media.
BACKGROUND OF THE INVENTION
[0002] The free radical polymerization of olefins and polar monomers such as acrylates in nonaqueous media using Brönsted or Lewis acids as catalysts is well known. Generally, such polymerizations result in low molecular weight polymers or oligomers that have some tendency to alternate between the nonpolar olefin and the polar monomer, often an acrylate. Typically, water is meticulously removed before the Brönsted or Lewis acid is added to the polymerization because of the reactivity between the acid and water.
[0003] Ethylenically unsaturated olefins without heteroatom substitution typically have low copolymerization rates with polar monomers such as acrylates. The copolymerization technology of, olefins with polar monomers is reviewed in WO 03/070783 and WO 2005/054305 both owned by PPG Industries Ohio, Inc. The olefins are described as electron donating type monomers and the acrylates are described as electron accepting monomers. Styrene copolymerization with maleic anhydride is discussed in WO 03/070783 in paragraph [0002] and described as forming charge transfer complexes and resulting in some alternating sequences. Styrene is a somewhat nonpolar monomer that does readily copolymerize with acrylates and other polar monomers by free-radical mechanisms even in the absence of charge complexation. While styrene does contribute to a more hydrophobic acrylate polymer, the resulting polymers have high glass transition temperature(s) and are not useful for many applications where soft-flexible film formation is desired. Therefore, there is a desire to have more hydrophobic olefins copolymerize with acrylates and other polar co-monomers to form moderate to low glass transition temperature polymers for use in many ink, adhesive, and coating applications.
[0004] In WO 03/070783, Examples A and B of the copolymers they feed 3 or 4 different charges into a reaction vessel over several hours maintaining a temperature of 140-160° C. and pressures from 5 psi to 62 psi in Example A and 40 to 360 psi in Example B. Molecular weights were number averages of 2293 and 4274 while the weight averages were 8317 and 12,856 gram/mole. These copolymers were blended with more conventional latexes and made into curable film forming compositions.
[0005] In WO 2005/054305, Examples 1-4 were 25/20155 w/w/w/ of isobutylene/hydroxypropyl acrylate/butyl acrylate polymerized into a copolymer by the method of the patent application. The monomers and di-t-amyl peroxide were prepared in three separate feed tanks and commingled in a teed line just prior to addition to the 5-gallon stirred reactor. The reactor was maintained between 200 and 210° C., at a pressure of 500 psi for a residence time of 16 to 25 minutes. The resulting polymer was reported to have a composition of 21 wt. % isobutylene, 27 wt. % hydroxypropyl acrylate, and 52 wt. % butyl acrylate. The copolymer was reported to have number average molecular weights between 1446 and 1699 and weight average molecular weights between 2781 and 3441 g/mole.
[0006] It would be desirable to copolymerize ethylenically unsaturated olefins of 4 to 30 carbon atoms with polar monomers such as acrylate monomers in large commercial reactors in aqueous media at 1 or 2 atmosphere pressure. It is also desired to make polymers over 50,000 molecular weight, preferably over 100,000 molecular weight to obtain optimum desired properties.
SUMMARY OF THE INVENTION
[0007] A polymeric reaction product resulted from polymerizing a) at least one ethylenically unsaturated aliphatic olefin with 2 or 4 to 30 carbon atoms with b) at least one ethylenically unsaturated monomer containing an electron withdrawing group, and c) optionally other ethylenically unsaturated monomers forming a copolymer comprising repeating units within the same copolymer from said at least one aliphatic olefin and said at least one monomer containing electron withdrawing group(s) in a media containing some water (also referred to as an aqueous media if appropriate) with a free radical initiator source in the presence of a Lewis or Brönsted acid. This polymeric reaction product is a stable emulsion of organic particles in aqueous media with good film formation properties. A film from the polymeric reaction product was found to have many desirable properties such as variable glass transition temperature, good barrier properties with respect to water and solvents, and a relatively hydrophobic surface. The resulting copolymer was unexpected as the experimentally measured reactivity ratios between olefins and such polar monomers indicate that copolymers should be disproportionately rich in the polar monomer. Further, the olefins are not strong electron donating monomers and the monomers containing electron withdrawing groups of the disclosure generally are not strong electron accepting monomers that would form charge complexes such as is known for styrene-maleic anhydride.
DETAILED DESCRIPTION OF THE INVENTION
[0008] Prior acrylate coatings provide many attractive performance properties, including good film-forming properties, balance of hard/soft (glass transition), adhesion to polar substrates (wood, metal, paper, polyester, nylon, ABS, concrete, etc.), oil resistance (with acrylonitrile added as monomer), and some moisture resistance by adding styrene monomer. Some elasticity and hydrophobicity can be produced with butadiene monomer, but, this generally results in poorer UV resistance. However, it is difficult to obtain other desirable properties, including moisture resistance with soft coatings, adhesion to low surface energy substrates such as PP (polypropylene) or PE (polyethylene), resistance to polar solvents and acid/base media, barrier properties to oxygen, low coefficient of friction (COF) including soft touch without stickiness, low temperature flexibility, and resistance to dirt pickup and certain stains.
[0009] To address these latter properties, it is necessary to incorporate hydrophobic (hydrocarbon-like aliphatic olefin(s)) components into the polymer. Some conventional ways of doing this include the use of acrylate esters of long chain alcohols, such as 2-ethylhexyl acrylate, or esters of versatates, such as dodecyl versatate, the use of an olefin/acrylate compatibilizer such as polymeric surfactants and the use of a fatty acid chain transfer agent. These methods increase cost and are limited by the amount of hydrophilic component that can be incorporated.
[0010] The direct incorporation of aliphatic olefin into the acrylate polymer backbone provides the potential for a low cost, versatile method for achieving the properties of a hydrophobically modified acrylate polymer coating. Although such a process has been a subject of study by polymer chemists for many years, these efforts have met with limited success. Many of these are reviewed in U.S. Patent Application 2005/0113515 A1 (May 26, 2005), which is equivalent to WO 05/54305 described in the Background of the Invention.
[0011] A further limitation of these methods is that they are in general performed in solution in homogeneous media resulting in low molecular weight and low physical and mechanical integrity. Most commercial acrylate polymers are made by heterogeneous aqueous emulsion processes that in general yield polymers with high molecular weight and superior physical and mechanical properties. This disclosure describes a free-radical initiator/acid catalyst system (optionally utilizing a solid particulate acid that can be removed after polymerization) that can co-polymerize olefins and acrylates in aqueous media in conventional acrylate copolymerization reactors at more conventional acrylate polymerization temperatures and pressures.
[0012] The solid or soluble versions of Lewis or Brönsted acids are part of the catalyst system with an aqueous media polymerization process (optionally emulsion), wherein the free radical initiator is selected from any known to those in this art, including peroxides (e.g., dibenzoylperoxide), hydroperoxides (e.g., t-butylhydropemxide), persulfates (e.g., sodium persulfate) or azo compounds (e.g., azobisisobutyronitrile, AIBN), redox initiator systems, and mixtures of these conventional free radical initiators. The monomers (which will be described later in more detail) are independently selected from:
[0000] a) an ethylenically unsaturated aliphatic alpha olefin, including but not limited to isobutylene, diisobutylene, nonene, or any other olefin containing a terminal olefin group,
b) at least one ethylenically unsaturated monomer containing an electron withdrawing group, alternatively described as an ethylenically unsaturated monomer containing a carbonyl or nitrogen group, such as an acrylate acid or ester including acrylic acid, methyl acrylate or ethyl acrylate, 2-ethylhexylacrylate, or any normal or branched alkyl acrylate with an alcohol component of 1 to 32 carbon atoms, and
c) optionally methacrylic acid or ester, styrene, acrylonitrile, vinyl chloride, vinyl amide or any other free-radically-polymerizable, olefin, and/or an electron rich olefin, including vinyl ethers or esters.
[0013] More specifically, in one embodiment, the solid acid component can be any solid containing Lewis or Brönsted acid groups. Examples of solid Brönsted acids are acidified clays (e.g., Engelhard F-24. superfiltrol or Sud-Chemie Tonsil® catalysts), sulfonated styrene divinylbenzene copolymers (Rohm and Haas Amberlyst® catalysts), heteropolyacids such as phosphotungstic acid (H 3 PW 12 O 40 ), fumed silica, silica/aluminas or zeolites. Examples of Lewis acids include any transition metal compound that is soluble or dispensable in the emulsion media, (including naphthenates of Fe, Co, Ni, Mn, Cr, or Mo) or solid or solid supported versions containing transition metal ions such as Fe 2 O 3 on alumina, or any of the above-mentioned soluble or dispersable transition compounds on a solid support such as montmorilinite (Bentonite) clays, silca, alumina, silica-aluminas and the like.
[0014] In another embodiment, liquid or water soluble Lewis or Brönsted acids (to the extent that they are inherently or can be made to be stable in the presence of water or in an aqueous media) can be selected from those disclosed in the prior art. Liquid or soluble Lewis or Brönsted acids (when stable in a media containing water) may be difficult to remove and may contribute to degradation or color in the polymer, which may be undesirable. Examples of liquid or water soluble Lewis or Brönsted acids include free radically polymerizable acids such as monomers containing carboxylic acid, phosphonic acid, sulfonic acid, etc., such as acrylic acid, itaconic acid, maleic acid, AMPS (acrylamide(2-methyl propane sulfonic acid) (available from Lubrizol Advanced Materials, Inc. in Cleveland, Ohio), etc. In one embodiment, the pKA value of the Lewis or Brönsted acid source is less than 6. In some limited embodiments, it may be desirable to exclude from the copolymer or reaction product (e.g., claim as free of, substantially free of, or having less than 100, 50, 25, 10, 5, 2, or 1 ppm based on the weight of all monomers to the polymerization recipe) either monomers containing acid groups (e.g., containing any of sulfonic, carboxylic, and phosphonic acid) or individually exclude using the same values the sulfonic, carboxylic, or phosphonic acid containing monomers.
[0015] Definitions. Unless otherwise indicated, the following terms have the following meanings:
[0016] As used herein, the term “wt. %” means the number of parts by weight of monomer per 100 parts by weight of polymer or copolymer on a dry weight basis, or the number of parts by weight of ingredient per 100 parts by weight of specified composition.
[0017] As used herein, the term “molecular weight” means number average molecular weight unless otherwise specified.
[0018] “Bulk polymerization” means the formation of polymer from substantially undiluted monomers. Incidental amounts of solvents, coalescents, plasticizers and/or water may also be present. Further description is given in “Bulk Polymerization”, Vol. 2, pp. 500-514, Encyclopedia of Polymer Science and Engineering, © 1989, John Wiley & Sons, New York, the disclosure of which is incorporated herein by reference.
[0019] “Solution polymerization” means a polymerization technique in which both the monomers and resultant polymer are substantially soluble in a diluent (e.g., organic solvents, coalescents, plasticizers and/or water) that is also present. It is described in “Solution Polymerization”, Vol. 15, pp. 402-418, Encyclopedia of Polymer Science and Engineering, © 1989, John Wiley & Sons, New York, the disclosure of which is incorporated herein by reference.
[0020] “Dispersion polymerization” means a polymerization technique in which polymerization of the monomers is at least initially carried out by bulk or solution polymerization, with the reaction system thereafter being emulsified or dispersed in an aqueous medium. It includes polymerization reactions in which polymerization is carried out to substantial or total completion before the bulk or solution polymerization system is dispersed in the aqueous medium. It is also known as secondary dispersion.
[0021] “Emulsion polymerization” means a polymerization technique in which the monomers are emulsified in an aqueous medium often containing a water-soluble initiator. Polymerization occurs predominantly in micelles formed by surfactant and not in the initially formed monomer droplets. Not to be bound by theory, the monomer droplets are thought to serve as a reservoir of monomers which diffuse out to find micelles and swell them. This mechanism produces polymer particles which are significantly smaller than original monomer droplets.
[0022] “Polymer” means a chemical substance consisting of one or more repeating units characterized by the sequence of one or more types of monomer derived units (monomer residues) and comprising a simple weight majority of molecules containing at least 3 monomer derived units which are covalently bound to at least one other monomer derived unit or other reactant. Such molecules can be distributed over a range of molecular weights and can be characterized by number-average and/or weight-average molecular weights and polydispersity index.
[0023] “Suspension polymerization” means a polymerization technique in which the monomers, normally together with an organic-soluble initiator, are first emulsified in an aqueous medium and thereafter the monomers are caused to polymerize. Because an organic-soluble initiator, is used, polymerization occurs throughout the bodies of the emulsified monomer droplets rather than in micelles, as in the case of emulsion polymerization. The result is that the polymer particles formed are typically larger than the polymer particles formed by emulsion polymerization.
[0024] The ethylenically unsaturated aliphatic olefin monomer(s) that are copolymerized with the polar monomers using the Brönsted or Lewis acid of this disclosure are unsaturated olefins with in one embodiment from 2 to 30 carbon atoms, in another embodiment from 4 to 30 carbon atoms, and in third, embodiment desirably 5 to 30 carbon atoms. They include branched and cyclic olefins but in preferred embodiments do not include styrenic monomers where the aliphatic nature is concluded after the first two carbon atoms of the ethylene unsaturation. In one embodiment, the formula of these molecules is CH 2 ═CR′R″ where R′ is a linear or branched C 1 to C 28 alkyl that may be linear, branched or cyclic and R″ is hydrogen or a linear or branched alkyl as set forth for R′, with the proviso that R′ and R″ together, have no more than 28 carbon atoms. Examples of ethylenically unsaturated aliphatic olefins include butylene, isobutylene, diisobutylene, pentene, hexane, octane, dodecene and other linear and branched olefins.
[0025] Free-Radical Polymerizable Monomers. Examples of free radical polymerizable monomers which are useful in forming the copolymers of this invention include acrylic esters, methacrylic esters, unsaturated nitriles, styrenic monomers, vinyl esters, vinyl ethers, conjugated dienes, olefins, halogenated (e.g., vinyl chloride and vinylidene chloride), allyl and other monomers, and mixtures thereof. The preferred ethylenically unsaturated monomers for achieving copolymerization with the ethylenically unsaturated aliphatic olefins in the presence of a Brönsted or Lewis acid are those with electron withdrawing groups or including carbonyl or nitrogen containing groups such as the acrylates, ethylenically unsaturated monomers with carboxylic acid groups such as acrylic acid, nitrite monomers such as acrylonitrile, vinyl amides, etc. Desirably, the monomers with the electron withdrawing groups are, characterized by the electron withdrawing group having a sigma σ (inductive component) value from 0.1 to 0.9 according to Bromilow et al., J. Org, Chem., 44, 4755 (1979). Later listed monomers that do not meet the definitions for achieving copolymerization with ethylenically unsaturated aliphatic olefins are listed as optional monomers to provide other properties to the copolymer(s). The list of monomers below includes some monomers that may have basic functional groups that interact unfavourably with the Lewis or Brönsted acids (possibly forming salts). It is anticipated that one skilled in the art would use such monomers with basic functional groups in such a way or in such limited amounts as not to interfere with the function of the Lewis or Brönsted acid in catalyzing the copolymerization of the ethylenically unsaturated olefin of 4 to 30 carbon atoms with the polar carbonyl containing monomer.
[0026] Specific examples include acrylic esters and methacrylic acid esters having the formula I:
[0000]
[0000] wherein R 1 is hydrogen or a methyl group, and R 2 contains about 1 to 100 carbon atoms, more typically 1 to 50 or 1 to 25 or 32 carbon atoms, and optionally, also one or more sulfur, nitrogen, phosphorus, silicon, halogen or oxygen atoms. Examples of suitable (meth)acrylate esters include methyl(meth)acrylate, ethyl(meth)acrylate, n-propyl(meth)acrylate, n-butyl(meth)acrylate, isopropyl(meth)acrylate, isobutyl(meth)acrylate, tert-butyl(meth)acrylate, n-amyl(meth)acrylate, n-hexyl(meth)acrylate, isoamyl(meth)acrylate, 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate, 4-hydroxybutyl(meth)acrylate, N,N-dimethylaminoethyl(meth)acrylate, N,N-diethylaminoethyl(meth)acrylate, t-butylaminoethyl(meth)acrylate, 2-sulfoethyl(meth)acrylate, trifluoroethyl(meth)acrylate, glycidyl(meth)acrylate, benzyl(meth)acrylate, allyl(meth)acrylate, 2-n-butoxyethyl(meth)acrylate, 2-chloroethyl(meth)acrylate, sec-butyl-(meth)acrylate, tert-butyl(meth)acrylate, 2-ethylbutyl(meth)acrylate, cinnamyl(meth)acrylate, crotyl(meth)acrylate, cyclohexyl(meth)acrylate, cyclopentyl(meth)acrylate, 2-ethoxyethyl(meth)acrylate, furfuryl(meth)acrylate, hexafluoroisopropyl(meth)acrylate, methallyl(meth)acrylate, 3-methoxybutyl(meth)acrylate, 2-methoxybutyl(meth)acrylate, 2-nitro-2-methylpropyl(meth)acrylate, n-octyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, 2-phenoxyethyl(meth)acrylate, 2-phenylethyl(meth)acrylate, phenyl(meth)acrylate, propargyl(meth)acrylate, tetrahydrofurfuryl(meth)acrylate, norbornyl(meth)acrylate, acrylamide and its derivatives, and tetrahydropyranyl(meth)acrylate. Mixtures of acrylic and methacrylic acid esters may be used. The polymerized acrylic and methacrylic acid esters typically may comprise up to 50, 75, 90 or 95 wt. % of the copolymer, depending on the amount of ethylenically unsaturated olefin desired in the copolymer.
[0027] Unsaturated nitrile monomers include acrylonitrile or an alkyl derivative thereof, the alkyl preferably having from 1 to 4 carbon atoms, such as acrylonitrile, methacrylonitrile, and the like. Also suitable are unsaturated monomers containing a cyano group such as those having the formula II:
[0000] CH 2 ═C(R)CO(O)CH 2 CH 2 CN (II)
[0000] wherein R is H or C n H 2n+1 and n is 1 to 4 carbon atoms. Other examples of unsaturated nitrile monomers include CH 2 ═C(CN) 2 , NC—CH═CH—CN, 4-pentenenitrile, 3-methyl-4-pentenenitrile, 5-hexenenitrile, 4-vinyl-benzonitrile, 4-allyl-benzonitrile, 4-vinyl-cyclohexanecarbonitrile, 4-cyanocyclohexene, and the like. Mixtures of the unsaturated nitriles may also be used. Acrylonitrile and methacrylonitrile are preferred. In some embodiments, the polymerized unsaturated nitrile monomers typically may comprise no more than about 60 wt. %, more typically no more than 20%, 15 wt. %, 10 wt. %, 5 wt. % or 3 wt. % of the copolymer.
[0028] The “styrenic monomers” useful in preparing the hydrophilic polymer(s) of this invention may be defined as monomers containing a carbon-carbon double bond in the alpha-position to an aromatic ring. For the purpose of this disclosure styrenic monomers will be considered neither to be ethylenically unsaturated aliphatic olefins nor ethylenically unsaturated monomers with electron withdrawing groups. Notwithstanding styrenic monomers may be included as co-monomer(s) in making the copolymers of this invention. Examples of suitable styrenic monomers include styrene, alpha-methylstyrene, tertiary butylstyrene, ortho, meta, and para-methylstyrene, ortho-, meta- and para-ethylstyrene, o-methyl-p-isopropylstyrene, p-chlorostyrene, p-bromostyrene, o,p-dichlorostyrene, o,p-dibromostyrene, ortho-, meta- and para-methoxystyrene, indene and its derivatives, vinylnaphthalene, diverse vinyl(alkyl-naphthalenes) and vinyl (halonaphthalenes) and mixtures thereof, acenaphthylene, diphenylethylene, and vinyl anthracene. Mixtures of styrenic monomers also may be used. Styrene and alpha-methylstyrene are preferred. In some embodiments where the repeating units from styrene type monomers are undesirable, the polymerized styrenic monomers typically may comprise no more than about than 80%, 60 wt. %, 40 wt. %, 20 wt. %, 10 wt. % or 5 wt. % of the copolymer.
[0029] Vinyl ester monomers derived from carboxylic acids containing 1 to 100, more typically 1 to 50 or 1 to 25, carbon atoms also may be useful in preparing the vinyl polymer of the present invention. Examples of such vinyl ester monomers include vinyl acetate, vinyl propionate, vinyl hexanoate, vinyl 2-ethylhexanoate, vinyl octanoate, vinyl pelargonate, vinyl caproate, neo esters of vinyl alcohol, vinyl laurate, vinyl versatate and the like, as well as mixtures thereof. The polymerized vinyl ester monomers, typically may comprise from 0 wt. % to about 99.5 wt. % of the vinyl polymer of the present invention.
[0030] Vinyl ethers may be useful in preparing the copolymer of the present invention. Examples of vinyl ethers include methyl-, ethyl-, butyl, iso-butyl vinyl ethers and the like. In one embodiment, the polymerized vinyl ether monomers typically may comprise from 0 wt. % to about 60 wt. %, preferably from 0 wt. % to about 50 wt. %, of the vinyl polymer of the present invention.
[0031] Conjugated diene monomers containing 4 to 12 carbon atoms, and preferably from 4 to 6 carbon atoms, also may be useful in preparing the polymer of the present invention. Examples of such conjugated diene monomers include butadiene, isoprene, pentadiene, and like, as well as mixtures thereof. Butadiene is preferred. As expressed earlier, diene monomers contribute to UV light sensitivity and possibly accelerate polymer degradation under UV light. Thus, in some embodiments where UV light will be present, the copolymers have less than 50. more desirably less than 30, more desirably less than 10 or 20, and preferably less than 5 wt. % repeating units from diene monomers.
[0032] Olefin monomers outside the definition of ethylenically unsaturated aliphatic olefins containing 4 to 30 carbon atoms may also be useful in preparing the vinyl polymer of the present invention. Examples of such olefins include ethylene and propylene, as well as mixtures thereof. Cyclic olefins may also be used such as vinyl cyclohexane, cyclopentene, cyclohexene, cyclooctadiene, norbornene, norbornadiene, pinene and like. In one embodiment, the copolymer may typically be comprised from 0 or 1 wt. % to about 50 wt. ° A, from 0 or 1 wt. % to about 20 or 30 wt. %, or from 0 wt. % to about 5 or 10 wt. %, of repeating units from ethylene, propylene or cyclic olefin monomers.
[0033] Ethylenically unsaturated monomers comprising fluorine, chlorine, bromine, and iodine may be useful in preparing the copolymer of the present invention. They may contain 2 to 100 carbon atoms and at least one halogen atom. Examples of such monomers include vinyl fluoride, vinyl chloride, vinyl bromide, vinylidene fluoride, vinylidene chloride, halogenated (meth)acrylic and styrenic monomers, allyl chloride and like, as well as mixtures thereof. Sometimes halogenated monomers or their repeating units are sensitive to degradation catalyzed by Lewis or Brönsted acids. Thus, in some embodiments, the copolymer of this invention will comprise less than 50 wt. %, more desirably less than 20 or 30 wt. % and more desirably still less than 5 or 10 wt. % of halogenated repeating units from these monomers.
[0034] Polar and Hydrophilic Monomers. Another group of monomers which are useful in preparing the copolymers of the present invention are polar monomers such as hydroxyalkyl(meth)acrylates, (meth)acrylamides and substituted (meth)acrylamides, sodium styrene sulfonate and sodium vinyl sulfonate, N-vinyl-2-pyrrolidone, caprolactam, 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate, 4-hydroxybutyl(meth)acrylate, (4-hydroxymethylcyclohexyl)-methyl(meth)acrylate, acrolein, diacetone (meth)acrylamide, 1-(2-((2-hydroxy-3-(2-propenyloxy)propyl)amino)ethyl)-2-imidazolidinone, N-methylol (meth)acrylamide, diallyl phosphate, Sipomer® WAM, WAM II (from Rhodia) and other urido-containing monomers, dimethylaminoethyl(meth)acrylate, and dimethylaminopropyl (meth)acrylamide, acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, citraconic acid, maleic anhydride, itaconic anhydride, citraconic anhydride, acrylamido(2-methyl propane sulfonic acid), and vinyl phosphonic acid. Mixtures of polar monomers also may be used.
[0035] Hydrophilic Monomers and Components. Hydrophilic components monomers, chain transfer agents, initiators) have at least one hydrophilic, ionic or potentially ionic group is optionally included in the copolymer to assist dispersion of the polymer, thereby enhancing the stability of the dispersions so made. Typically, this is done by incorporating a compound bearing at least one hydrophilic group or a group that can be made hydrophilic e.g., by chemical modifications such as neutralization or deblocking) into the polymer chain. These compounds may be of a non-ionic, anionic, cationic or zwitterionic nature or the combination thereof.
[0036] For example, anionic groups such as carboxylate, sulfate, sulfonate, phosphate, and phosphonate can be incorporated into the polymer in an inactive form and subsequently activated by a salt-forming compound, such as ammonia, organic amines and alkali metal hydroxides. Other hydrophilic compounds can also be reacted into the polymer backbone, including lateral or terminal hydrophilic ethylene oxide, the organic amines and polyamine/polyimines previously described as chain extenders for polyurethanes, pyrrolidone or ureido units.
[0037] Hydrophilic compounds of particular interest are those which can incorporate acid groups into the polymer such as ethylenically unsaturated monomers having at least one carboxylic acid group, and preferably one or two carboxylic acid groups. Examples of such monomers include acrylic acid, methacrylic acid, itaconic acid, maleic acid, maleic anhydride, fumaric acid, crotonic acid, vinyl acetic acid, mesaconic acid, citraconic acid, 2-acrylamido-2-methylpropanesulfonic acid, styrene sulfonic acid, 2-sulfoethyl(meth)acrylate, alkali metal salts of the above acids and amine or ammonium salts thereof such as sodium allyl sulfonate, sodium 1-allyloxy-2-hydroxypropane sulfonate (COPS 1), 2-acrylamido-2-methyl propane sulfonate (AMPS), sodium dodecyl allyl sulfosuccinate (TREM-LF40), sodium methallyl sulfonate, sodium styrene sulfonate, sodium vinyl sulfonate, sodium vinyl phosphonate, sodium sulfoethyl methacrylate.
[0038] Strong acid monomers are also desirable in the copolymer. Examples of ethylenically unsaturated strong acid monomers useful according to the invention include, but are not limited to, 2-acrylamide-2-triethylpropane sulfonic acid, 1-allyloxy-2-hydroxypropane sulfonic acid, vinylsulfonic acid, styrene sulfonic acid, alkyl allyl sulfosuccinic acid, sulphoethyl(meth)acrylate, phosphoalkyl(meth)acrylates such as phosphoethyl methacrylate (phosphate ester of 2-hydroxyethyl methacrylate), phosphoethyl acrylate, phosphopropyl(meth)acrylate, phosphobutyl(meth)acrylate, phosphate ester of polyethyleneglycol(meth)acrylate, phosphate ester of polypropyleneglycol(meth)acrylate, phosphoalkyl crotonates, phosphoalkyl maleates, phosphoalkyl fumarates, phosphodialkyl(meth)acrylates, phosphodialkyl crotonates, vinyl phosphonic acid (VPA) and allyl phosphate. Salts of these unsaturated strong acid monomers are also useful. Diesters and blends of monesters and diesters of the phosphate strong acids are useful also. The term “(meth)acrylate,” and the like, as used throughout means either an acrylate, or a methacrylate, or mixtures of both. In a preferred embodiment, the ethylenically unsaturated strong acid monomer is a phosphorous-containing monomer, and especially an unsaturated phosphate ester such as phosphoethyl methacrylate (phosphate ester of 2-hydroxyethyl methacrylate).
[0039] Compounds/Monomers Having at Least One Crosslinkable Functional Group. Compounds having at least one crosslinkable functional group can also be incorporated into the vinyl polymers of the present invention, if desired. Examples of such compounds include N-methylol acrylamide (NMA), diacetone acrylamide (DAAM), acetoacetoxy ethyl methacrylate (AAEM), epoxy-containing compounds, —OH containing compounds, —COOH containing compounds, isocyanate-containing compounds (TMI), mercaptan-containing compounds, compounds containing olefinic unsaturation and the like. Mixtures can also be used.
[0040] Following polymerization of the ethylenically unsaturated aliphatic olefin with the at least one ethylenically unsaturated monomer containing an electron withdrawing group, it is often desirable to reduce the volatile organic content (VOC) of the polymerization product so that downstream products from the polymer dispersion can be formulated to be compliant with various volatile organic component limitations imposed by regional governments. By VOC, according to the present invention, it is meant the sum of the residual monomers and additional volatile organic compounds (e.g., diluents and degradation products) which are determined by the chromatographic gas method. While VOC may have a different definition by different groups, a preferred definition from the European Union Directive 2004/42/CE for VOC emissions from varnish defines VOC as an organic compound having an initial boiling point less than or equal to 250° C. measured at a standard atmospheric pressure of 101.3 kPa. As defined hereunder; more precisely the total VOC according to the present invention is desirably lower than 600, 500, 200, 100, 20, or 10 ppm and in particular the monomers, which are substances sometimes toxicologically harmful, lower than 500, 200, 100, 50, 20, or 10 ppm. A low VOC is typically less than 500 ppm, more preferably less than 250 ppm and most preferably less than 50 ppm. There are commercial methods or technology for removing volatile organics and residual monomers such as steam stripping, coagulation and washing or drying, etc. Removing VOCs soon after polymerization also avoids more restrictive shipping and storage requirements that might be required if more significant amounts of volatile and potentially flammable organics are present in the headspace of partially filled containers, tanks, trucks, etc.
[0041] Other Additives for the Polymer. Other additives well known to those skilled in the art can be used in combination with the copolymer. Such additives include stabilizers, defoamers, antioxidants (e.g., Irganox™1010), UV absorbers, activators, curing agents, stabilizers such as carbodiimide, colorants, neutralizing agents, thickeners, non-reactive and reactive plasticizers, coalescing agents such as di(propylene glycol) methyl ether (DPM) and PM acetate, waxes, slip and release agents, antimicrobial agents, surfactants such as ionic and nonionic surfactants (e.g., Pluronic™ F68-LF, IGEPAL™ CO630) and silicone surfactants, metals, salts, antiozonants, and the like.
[0042] Blends with Other Polymers and Polymer Dispersions. The polymers of this invention can be combined with commercial polymers and polymer dispersions by methods well known to those skilled in the art.
[0043] The polymer may be applied as a dispersion in a media to form a coating, adhesive, sealant, etc. It may be applied by brushing, dipping, flow coating; spraying, rolling, etc. It may contain conventional ingredients such as solvents, plasticizers, pigments, dyes, fillers, emulsifiers, surfactants, thickeners, theology modifiers, heat and radiation stabilization additives, defoamers, leveling agents, anti-cratering agents, fillers, sedimentation inhibitors, U.V. absorbers, antioxidants, flame retardants, etc. It may contain other polymeric species such as additional polymers in the forms of blends, interpenetrating networks, etc.
[0044] In one embodiment, the polymerization temperature is 0 to about 100 or 150° C. preferably 5 to about 95° C. and more preferably about 10 to about 90° C. In one embodiment, the reactor pressure after charging the monomers and during polymerization is from atmospheric pressure (about 1 atmosphere) to about 10 atmosphere, more desirably from about atmospheric to about 2 or 3 atmosphere. In one embodiment, it is desirable that a conventionally equipped acrylate polymerization vessel designed for use at 1 or 2 atmospheres could be used so that equipment costs would not be a determent to using this technology.
[0045] In one embodiment, desirably the pH of the polymerization media would be from about 1 to about 10, more desirably from about 1 to about 7, more desirably from about 2 to about 5. In one embodiment, emulsifiers/dispersants/surface active molecules, to the extent necessary, would be chosen so that they performed any necessary function at the desired or selected pH.
[0046] In one embodiment, the polymerization media can be about any media that doesn't negatively interact with the monomers, initiators, and other components to the polymerization, and in particular including small or large amounts of water. Organic solvents (both polar and nonpolar) may be present but generally are not required. In one embodiment, the polymerization media is desirably at least 100 or 500 ppm or 1, 2, 5, 10, 15, or 20 to about 30, 50, 70, 80, 90 or 99 wt. % water based on the continuous media/aqueous media and any dispersed phase therein, e.g., monomers, surfactants, initiators, chain transfer agents, Lewis or Brönsted acid, copolymers, etc. Water, to the extent present, can be from any source, e.g., de-ionized, distilled, city water, etc.
[0047] In one embodiment, the copolymers from this process desirably have a number average molecular weight in excess of 2,000; more desirably in excess of 3,000 or 5,000; and in other embodiments desirably in excess of 10,000; 25,000; 50,000; or 100,000 grams per mole. Molecular weights as stated will be determined by GPC analysis using polystyrene standards. Molecular weights from about 25,000 and higher often typical of emulsion polymerization. Typically, the weight average molecular weight of many polymers and polymerization mechanism will be about double the number average molecular weight. In one embodiment, desirably these copolymers will have a weight average molecular weight in excess of 4,000; more desirably in excess of 6,000 or 10,000; and in other embodiments desirably in excess of 20,000; 50,000; 100,000; or 200,000 grams per mole. These molecular weights may be claimed in combination with emulsion polymerization mechanisms.
[0048] The polymerization mechanism can be any of those known to the art (e.g., dispersion, emulsion, bulk, solution, etc). In one embodiment, it is desirable for ease of handling of the polymer that the final copolymer (e.g., in aqueous media) be a dispersion that can be pumped and handled as a liquid. It is desirable that the number average particle size be below 5 microns, more desirable below 1 micron, and in some embodiments less than 800, less than 500; less than 300, or less than 200 nanometers in diameter. The particles sizes of less than 500 nanometers and below are typical of emulsion polymerization and may be claimed in combination with an emulsion type polymerization mechanism.
[0049] Typically, one wants both co-monomers and the optional co-monomers to be chemically bonded into the same polymer chain, unless one wants an interpenetrating polymer network of two separate polymers. The copolymers can have randomly inserted monomers, alternating insertion of monomers, blocky insertion of repeating units from a single monomer, etc. As one goes from blocky insertion to random to perfectly alternating insertion, the percentage of any first type of repeating unit adjacent to another type of repeating unit increases. In one embodiment, desirable at least 5, 10, 15 or 20 weight percent of the copolymer are the sum of a) repeating units from said ethylenically unsaturated olefin covalently bonded to at least one repeating unit from said ethylenically unsaturated monomer with electron withdrawing group (or carbonyl or nitrogen containing group) with b) repeating units from said ethylenically unsaturated monomer with electron withdrawing group covalently bonded to at least one repeating unit derived from said ethylenically unsaturated aliphatic olefin. In one embodiment, desirably at least 5, 10, 15 or 20 weight percent of the repeating units from said ethylenically unsaturated monomer with electron withdrawing group are covalently bonded to at least one repeating unit from said ethylenically unsaturated olefin. Similarly, in one embodiment, desirably at least 5, 10, 15 or 20 weight percent of the repeating units from said ethylenically unsaturated olefin are covalently bonded to repeating units from said, ethylenically unsaturated monomer with electron withdrawing groups.
[0050] While not wishing to be bound by theory, the mechanism by which this co-polymerization takes place is postulated to involve sequential formation of electron poor and electron rich terminal end groups on the growing polymer resulting from alternating addition of olefin and acrylate.
[0051] A unique feature of many of the examples in this invention is that generally in the NMR analysis of polymers from this process, alternating sequences of the a) ethylenically unsaturated aliphatic olefin with 4-30 carbon atoms with the b) at least one ethylenically unsaturated monomer containing an electron withdrawing group (alternately defined in some claims as an ethylenically unsaturated monomer containing a carbonyl or nitrogen group) exist in the copolymer, often along with sequences or blocks of the b) monomer. The presence of both alternating sequences of the two types of monomers and homopolymer blocks within the same reaction product seems unique, In on embodiment, it is desirable that at least 2, 5, 10, or 20 mole percent of all the repeating units in the copolymer are the sum of said a) ethylenically unsaturated aliphatic olefin with 4 or 5 to 30 carbon atoms covalently bonded to at least one of said b) at least one ethylenically unsaturated monomer containing an electron withdrawing group (alternately defined in some claims as an ethylenically unsaturated monomer containing a carbonyl or nitrogen group) combined with said b) at least one ethylenically unsaturated monomer containing an electron withdrawing group (alternately defined in some claims as an ethylenically unsaturated monomer containing a carbonyl or nitrogen group) covalently bonded to at least one of said a) ethylenically unsaturated aliphatic olefin with 4 or 5 to 30 carbon atoms. Alternatively, in another embodiment (or in combination with the limitations above characterizing said alternating sequences), at least 2, 5, 10, or 20 mole percent of all the repeating units in the copolymer are the sum of said b) at least one ethylenically unsaturated monomer containing an electron withdrawing group (alternately defined in some claims as an ethylenically unsaturated monomer containing a carbonyl or nitrogen group) covalently bonded to repeat units from monomers other than said a) ethylenically unsaturated aliphatic olefin with 4 or 5 to 30 carbon atoms (e.g., the copolymers have the specified amount of blocks of said b) at least one ethylenically unsaturated monomer containing an electron withdrawing group (alternately defined in some claims as an ethylenically unsaturated monomer containing a carbonyl or nitrogen group) not alternating with said a) a) ethylenically unsaturated aliphatic olefin with 4 or 5 to 30 carbon atoms.
[0052] The copolymer product can be used in OEM (original equipment manufacturing) plastics including automotive and consumer electronics; weatherable coatings for building and the construction industry, textile coatings for home furnishings and automotive, printing inks and primers for flexible packaging. It may be used as a dispersion in aqueous media or precipitated to isolated the polymer (e.g., as a dry powder, bulk polymer, or slurry) and used as an additive, impact modifier, etc. for another plastics. It is particularly useful in applications requiring additional hydrophobic character in coatings, primers, inks, compatibilizers, adhesives, sealants, caulks, textile coatings, and composite materials. The copolymers could be used in personal care, pharmaceutical or pharmacologically active formulations to change the feel, viscosity, surface character, delivery mechanism, etc. of such formulations.
EXAMPLES
Chemicals Used in Examples
Comparative Example 1
[0053] Baseline emulsion polymerization without DIB and catalyst.
[0000] TABLE 1 Reactants for Subsequent Tables Chemical CMP Name Name Source 1 Rhodaplex EST-30 Rhodia 2 Methyl Methacrylate MMA J T Baker 3 Butyl Acrylate BA 4 Methacrylic Acid MAA Aldrich
Purpose: to prepare a latex emulsion polymer. Preparation:
1. Monomer pre-emulsion preparation:
a. 0.51 g sodium bicarbonate was added to a beaker followed by 51 g water and 1.7 g EST-30. The mixture was blended with a spatula until homogeneous and then added to an addition funnel equipped with an overhead stirrer with a glass shaft and crescent shaped Teflon blade. b. The three monomers MMA, BA and MAA were added to the addition funnel while mixing after each addition. A milky white emulsion formed. c. The emulsion was continuously stirred to maintain the emulsion.
2. Initial reactor charge
a. 0.17 g sodium bicarbonate was added to a beaker followed by 110.5 g water and 1.7 g EST-30. The mixture was blended with a spatula until homogeneous and then added to a 1 L 4-neck, flask. b. The flask was equipped with an overhead stirrer with a glass shaft and crescent shaped Teflon blade, thermocouple, condenser and N 2 inlet. c. The stirring rate was set at 200 rpm.
3. Reaction
[0000]
a. The contents of the reactor were heated to 78° C.
b. Initiator I solution was prepared (0.17 g sodium persulfate and 3.4 g water) and added all at once to the reactor.
c. The monomer pre-emulsion was added to the flask over 3 hours via addition flannel.
d. 45 minutes after the monomer pre-emulsion addition started, the initiator II solution (0.51 g sodium persulfate and 17 g water) addition was started, The initiator II solution was added over 3 hours using, an addition funnel.
e. Upon completion of the monomer pre-emulsion, the addition funnel was rinsed with 8.5 g of water (in three portions).
f. Upon completion of the initiator 11 solution, the reaction was held at 78° C. for 1.5 hours then cooled.
g. The milky-white reaction liquid was filtered through a cloth pad. 341.81 g milky-white liquid filtrate (product) was collected. A small amount (1.57 g) of white solids stuck to the stirring shaft, thermocouple, and flask.
Comparative Example 2
[0067] Emulsion polymerization baseline with DIB (diisobutylene) and no catalyst.
[0068] The procedure for this experiment was the same as for Comparative Example 1 except that 34.69 g of DIB was added to the reactor and the BA charge was reduced to 39.70 g (see formulations in Table 2).
Example 3
[0069] Emulsion polymerization with DIB and Amberlyst 35 catalyst.
[0070] The procedure for this experiment was the same as for Comparative Example 2 except that 30 g of wet Amberlyst 35 (50 wt % water) was added (see formulations in Table 2)
[0000]
TABLE 2
Emulsion Polymer Formulations
Comp
Comp
Example
Ex 1
Ex 2
Ex 3
Monomer Premix
Water
51.00
51.00
51.00
Rodapex EST-30
1.70
1.70
1.70
Sodium bicarbonate
0.51
0.51
0.51
MMA
88.4
88.4
88.4
BA
79.39
39.70
39.70
MAA
2.21
2.21
2.21
Rinse water
8.50
8.50
8.50
Reactor Charge
Water
110.50
110.50
110.50
Sodium bicarbonate
0.17
0.17
0.17
Rodapex EST-30
1.70
1.70
1.70
Diisobutylene (DIB)
34.69
34.69
Amberlyst 35
15.00
Initiator I
Water
3.40
3.40
3.40
Sodium persulfate
0.17
0.17
0.17
Initiator II
Water
17.00
17.00
18.00
Sodium persulfate
0.51
0.51
0.51
Yield
341.80
347.01
272.96
Solids (wet)
1.57
32.00
Theory yield
365.16
360.16
361.16
(less solid cat)
% Yield
93.6
96.3
75.6
Product appearance
milky
milky
milky
white
pale blue
white
% Solids exp
46.00
36.75
40.50
% Solids theoretical
47.20
46.50
46.50
% Solids if no DIB
47.20
36.80
36.80
incorporated.
Dried film
clear
clear
clear pale
appearance
golden
GC Latex
MMA (ppm)
368
18136
883
BA (ppm)
0
27957
777
DIB (ppm)
0
80243
55615
% DIB
0.00
8.02
5.56
% DIB charged
0
9.60
9.60
DSC Tg, C (major)
24
64
54
[0071] Comparing the % solids and Gas Chromatograph results for Examples 2 and 3 in Table 2, higher % solids and more DIB conversion occurred when the Amberlyst 35 was used.
[0072] Comparing the DSC data, Example 3 has a lower Tg compared to Example 2. This is consistent with DIB incorporation since it is expected that the incorporation of DIB would lead to “softer” polymer films.
[0000]
TABLE 3
Emulsion Polymer Formulations
Example
Example
Example
4
5
Monomer Premix
Water
33.22
33.00
Rodapex EST-30
1.10
1.12
Sodium bicarbonate
0.33
0.33
MMA
0
0
BA
108.46
107.80
MAA
1.43
1.30
Rinse water
8.05
8.05
Reactor Charge
Water
160.58
160.54
Sodium bicarbonate
0.17
0.18
Rodapex EST-30
0.87
0.86
Igepal CO-850
0.87
0.86
Aerosol OT-75
0.86
0.87
Diisobutylene (DIB)
33.7
0
Initiator I
Water
3.48
3.42
Sodium persulfate
0.18
0.18
Initiator II
Water
19.11
18.04
Sodium persulfate
0.53
0.51
Yield
356.60
328.30
Solids (wet)
1.07
2.01
Theory yield
373.49
337.32
(less solid cat)
% Yield
92.8
93.4
Product appearance
milky
milky
white
white
% Solids exp
34.90
33.10
% Solids theoretical
39.50
33.40
% Solids if no DIB
30.40
33.40
incorporated.
Dried film
clear
clear
appearance
GC Latex
BA (ppm)
5045
7470
DIB (ppm)
7494
0
% DIB
0.75
0
% DIB charged
9.02
0
[0000]
TABLE 4
Other similar polymerization experiments using different
Lewis or Brönsted acids where % solids analysis
indicated DIB (diisobutylene) incorporation.
% solids
% solids
% solids if no
Example
Catalyst
exp
theory
DIB incorp.
Example 6
Iron
22.30
25.36
20.19
naphthenate
Example 7
Amberlyst 35
22.30
25.36
20.19
dried
Example 8
Amberlyst 35
21.33
25.36
20.19
dried
Example 9
Scandium
21.33
25.36
20.19
triflate
Example 10
Amberlyst 35
21.00
24.44
19.49
dried
Example 11
AMPS
24.00
27.10
22.02
Example 12
Amberlyst 35
31.80
29.38
43.60
dried
AMPS is acryamido (2-methyl propane sulfonic acid) sodium salt or acid available from Lubrizol Advanced Materials, Inc. in Cleveland, Ohio.
[0073] Samples of coatings from Examples 4 (with DIB) and Example 5 (without DIB) from Table 3 were tested to see if the presence of DIB in the polymer promoted adhesion to a variety of thermoplastic olefin (TPO), high density polyethylene (HDPE), low density polyethylene (LDPE), and polypropylene (PP) substrates. The actual peel test was done by pulling for 5 second at 40 in/min speed with an IMASS TL-2200 Slip/Peel tester, Due to the low surface energy of TPO, PP, and PE substrates, the liquid latex films (from Examples 4 and 5 will crawl on those substrates during film drying process. Cheese cloth method is a good way to prevent the polymer from crawling during the film formation. The latex polymers were tested as they existed without any added polymers, pigments, dispersants, etc. There is no need to add extra surfactants to help film spread. Four layers of cheese cloth (1″×10″) were put on the test various substrates (3″×6″), and the cloth was saturated with latex polymer (about 5 grams). The latex polymers were dried 7 days before the peel tests were run. The results are reported in Tables 5a through 5e.
[0000]
TABLE 5
(substrates a-e).
Peel Strength Test - After 1 week (dry films)
Latex Example 4,
Latex Example 5,
with DIB
without DIB
5a Substrate: TPO-Solvax DEXFLEX D161-LC-3 55031A (lot 1318413)
Peel Strength
1416
75.4
Peak Peel Strength
1909.4
174.4
Static Peel Strength
1368.5
131.4
5b Substrate: TPO-Solvax Sequel 2330 code 54881TR (lot 2350711)
Peel Strength
1331.8
109.7
Peak Peel Strength
1841.9
214.6
Static Peel Strength
1155.2
167.4
5c Substrate: HDPE-Dow DMDA 8097NAT (lot SD0844Q72G)
Peel Strength
525
79.7
Peak Peel Strength
680
129.8
Static Peel Strength
715.8
85.2
5d Substrate: LDPE-Dow PE722NT (lot SC01015151)
Peel Strength
591.9
56.6
Peak Peel Strength
602.8
112.1
Static Peel Strength
619.1
67.1
5e Substrate: PP-A. Schulman Polyfort 1948HU315 (lot A0143342)
Peel Strength
1474.1
214.8
Peak Peel Strength
1683.3
307.4
Static Peel Strength
1496.4
250.2
[0074] While the invention has been explained in relation to its preferred embodiments, it is to be understood that various modifications thereof will become apparent to those skilled in the art upon reading the specification. Therefore, it is to be understood that the invention disclosed herein is intended to cover such modifications as Fall within the scope of the appended claims. | A polymerization process to copolymerize hydrophobic ethylenically unsaturated C 4 -C 30 . J olefins with polar monomers such as acrylates is described. The process utilizes an acid source to modify/catalyze the reactivity of the polar monomer and/or radically activated repeat unit from the polar monomer to promote incorporation of the ethylenically unsaturated olefin. The copolymer shows excellent adhesion to a variety of polymeric and/or polar substrates such as polyolefins, acrylatc coatings, wood, etc. | 2 |
BACKGROUND OF THE INVENTION
In some automotive vehicle bodies, such as found in hardtop models in which the door window panel opening is not surrounded by a frame, the vehicle window is guided in its raising and lowering movements solely by a window regulator mechanism and a fixed guide rod, both of which are mounted within the window well formed by outer and inner panels of the door structure. When the window panel is fully raised it must meet and rest against resilient body seals mounted on the vehicle body structure framing the door opening.
In a conventional installation, a guide bracket is bolted or otherwise secured to a lower portion of the window panel. The guide bracket has upper and lower flanges that extend laterally of the plane of the window panel toward the guide rod. Mounted on the flanges are guide members that slidably engage the guide rod. The guide members are bolted to the flanges, either the flanges or guide members being provided with oversized holes or slots to permit adjustment of the window panel to be made to insure that the panel will be properly seated relative to the body seals or weather strips.
Under current in-plant procedures, during body assembly, the individual responsible for the fitting of the window panel to the door opening and the body seals must estimate the adjustment necessary to properly meet the seals. The individual then must open the partially assembled door, make the estimated adjustment, and then close the door to determine if the adjustment was proper. If the adjustment was not correct, as is often the case, the procedure must be repeated. Due to assembly line speed, however, the individual runs out of either time or patience and merely tightens down the guide member bolts without achieving an optimum fit of the window panel to the body seals. Consequently, the fits are poor and warranty problems, such as extensive wind noise and water leakage, are created.
As noted in U.S. Pat. No. 4,051,632 issued Oct. 4, 1977 to R. Fukumoto, et al. for "Window Glass Mounting Means for Automobiles", it is necessary in order to insure proper locations of the window glasses with respect to the weather sealing strips, to employ adjustment devices in the window glass guide means so that the lateral positions of the upper edges of the window glasses can be adjusted as desired. Patentee further points out that conventional adjusting mechanisms have been found disadvantageous because it is required to make adjustments at two bolt-slot connections. Fukumoto, et al. state it was an object of their invention to provide window glass mounting means with means for adjusting the lateral position of the window glass through actuation of a single screw. Even the single screw adjustment device, however, does not overcome the objection that the assembly line worker must open and close the vehicle door several times to see that a proper fit has been made, and if not made, to further adjust the actuating screw.
SUMMARY OF THE INVENTION
The present invention relates to a vehicle window assembly having a window panel movable in spaced relationship to and along a fixed guide rod during the raising and lowering movements of a window panel. A guide bracket is mounted on a lower portion of the window panel and has upper and lower flange portions extending laterally toward the guide rod. A first guide means is secured to the upper flange portion, the first guide means having a slot therein extending laterally of the window panel. A second guide means is secured to the lower flange portion and has an aperture centrally located and in alignment with the slot in the first guide means. The guide rod projects through the slot and the aperture in the respective guide means and has sliding engagement with the side walls only of the slot and with the aperture wall.
The first and second guide means coact with the guide rod to stabilize the window panel against tilting movement in the plane of the panel, as in a conventional installation. The second guide means further coacts with the guide rod to maintain the window panel in spaced relationship to the guide rod. An important feature of the present invention is that the lower flange portion of the guide bracket attached to the window panel is moveable relative to the second guide means through which the rod projects to adjust the position of the window panel relative to the guide rod. A retainer means is anchored to the lower flange portion. The retainer means and the second guide means have coacting ratchet means adapted to hold the window panel temporarily in adjusted position. A fastening means is provided for immovably securing the lower flange portion and second guide means to each other after a desired adjustment position of the window panel is achieved.
Accordingly, the present invention allows the operator of the assembly line to set the glass from the outside of the vehicle. Once the position is obtained in which the glass is properly seated against the body seals, the retainer means holds the glass in position through the ratcheting action between the retainer and second guide means. The assembly line worker would then secure the two bolts which are currently used to hold the glass in position to make the permanent installation. Or, this could be done at a point further down the assembly line by the individual responsible for trim panel installation.
DESCRIPTION OF THE DRAWING
Other advantages and features of the present invention will become more apparent as the description proceeds, reference being had to the accompanying drawing wherein:
FIG. 1 is a perspective view of a window glass adjusting device embodying the present invention;
FIG. 2 is an enlarged sectional view on a line 2--2 of FIG. 1; and
FIG. 3 is an enlarged sectional view on a line 3--3 of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to sheet 2 of the patent drawings in U.S. Pat. No. 4,051,632 referenced in the background statement of this specification, and more particularly to FIG. 2 thereon, there is shown an automobile window glass panel adapted to be raised and lowered by a conventional single arm window regulator coupled to a channel member carried on a bracket secured to the lower edge of the glass. To stabilize the glass panel against tilting movement in its plane and also against lateral movement, the bracket is provided with upper and lower guide means slidable on a substantially vertically extending rod.
The present invention is concerned with the structure of the bracket, the guide means and the rod, and the manner in which the three coact to stabilize the glass panel against tilting in its plane and against movement laterally. More particularly, the present invention is concerned with the provision of an adjustment device for permitting rapid assembly line positioning of the glass panel relative to the fixed rod so that the panel will properly be positioned in the vehicle body or door opening to make optimum sealing contact with the elastomeric seals or weatherstrips mounted around the inner perimeter of the body or door opening. Accordingly, reference is now made to FIGS. 1-3 of the drawing accompanying this specification.
In FIG. 1, there is shown a fragmentary portion of a vehicle window panel 10 having secured thereto a bracket 11. The bracket 11 has a laterally extending upper flange 12 that carries an upper guide means, generally designated 13, and a laterally extending lower flange 14 that carries a lower guide means, generally designated 15. The upper guide means 13 is conventional and comprises an elongated flat member 16, preferably molded of plastic, that straddles a centrally positioned cut-out or notch 17 in the flange 12. The body member 16 has a centrally positioned, laterally extending slot 18 therein that is surrounded above and below the body member by a reinforcing rim or wall 19. The body member 16 is bolted by suitable bolts 21 to the upper flange portion 12.
The lower guide means 15 is structurally more complex than the upper guide means 13. It, too, comprises a centrally reinforced body member 22 that straddles a notch 23. The body member 22 has through its centrally reinforced center portion a centrally positioned aperture 24. As best seen in FIG. 2, the aperture 24 has pairs of diametrically opposed projections 25 and 26 projecting inwardly toward its center, the projections 25 and 26 being adapted to slidably engage the guide rod 27 that guides the window panel during its upward and downward movement. The center of the aperture 24, when the lower guide means 15 is mounted on the lower flange 14, is vertically aligned with the lateral center of the slot 18 in the upper guide means 13. In the case of the upper guide means, the rod 27 is slidably engaged with the side walls of the slot 18. The slot 18 permits the guide means 15 to be moved laterally relative to the rod 27 as is necessary, for a reason to become apparent.
The lower guide means body member 22 has laterally extending slots 28 on each side of the aperture 24, the slots 28 receiving bolts 29 that project through bolt holes 31 in the flange portion 14 on each side of the notch 23.
In a conventional vehicle window assembly, the glass panel would be adjusted to fit the body seals around the window opening by a trial and error method at one station in the vehicle body assembly line. With the door closed, the individual responsible for the fit of the panel to the body seals would determine if the glass panel should be moved laterally inwardly or outwardly to provide the proper seal engagement. The individual then would have to open the door and apply lateral pressure to the panel to move it inwardly or outwardly, as required. Because of the slot 18 in the upper guide means 13, the latter is free to move relatively to the guide rod 27 with the glass panel and bracket 11. The lower guide means 15, as will be readily apparent, does not have this freedom of movement and, therefore, the lower flange 14 of the bracket 11 moves laterally with respect to the guide means 15 as permitted by the slots 28 in the guide means body member 22. The individual making the adjustment must then close the door to test the fit of the glass panel against the body seals. This operation may have to be repeated several times, if the panel fitter does not run out of patience or time, before a final setting is determined so that the bolts 29 and nuts 31 may be tightened to render the guide means 15 and flange 14 relatively immovable to one another.
In the present invention, a quick adjustment device is inserted between the heads of the bolts 29 and the upper guide means 15. The quick adjustment device comprises a pair of retainer means, each generally designated 32. Each retainer means 32 is a molded resilient plastic member having a substantially flat main body portion 33 terminating in a slightly curved end flange 34. The body portion 33 is apertured to receive the bolt 29. The main body portion 33 has on its underside a downwardly projecting rib 35 extending across its lateral width. As best seen in FIG. 3, the rib 35 projects into a groove or recess 36 extending across the width of the body member 22 of the lower guide means 15. At each end the guide means body member 22 has a series of serrations or ratchet teeth 37. Integral with the curved flange 34 on the end of each retainer means 32 is a vertical rib 38 having on its surface facing the serrations or teeth 37 on the guide means body member 22 at least a couple of vertical teeth 39. Each retainer means body portion 33 has an enlarged opening 41 extending from the flange 34 wall to the rib 35 for a substantial portion of the width of body portion 33 to enhance the flexibility of the flange 34 in the area of the toothed rib 38.
A Belleville type washer 42 may be used beneath the head of the bolt 29 and the upper surface of the body portion 33 of the retainer means 32.
The quick adjustment device as described permits rapid setting of the window panel 11 against the body seals. When the vehicle body approaches the window fitters assembly line station, the bolts and nuts holding the lower guide means 15 and guide bracket lower flange 14 in assembled relation are in a loose condition. The window fitter is able to set the window panel against the body seal by merely pushing or pulling on the upper extremeties of the window panel from the outside of the vehicle. Movement of the window panel 11 and flange portion 14 relative to the guide means 15 causes the retainer means 32 above each end of guide means 15 to move laterally of the latter. This causes the teeth 39 on the retainer means flanges 34 to ratchet on the opposed serrations or teeth 37 on each end of the main body member 22 of the guide member 15. The coaction between the rib 35 on each retainer means body portion 32 with the recess 36 in the body member 22 of the guide means 15 causes the teeth 39 on the retainer means to move across the teeth 37 on body member 22 without causing the retainer means to rotate around the bolt 29. Once the desired window panel position is attained, the resilient retainer means 32 will hold the panel in the desired position. The assembly line worker then only has to secure the bolts 29 to permanently secure the guide means 15, the retainer means 32 and the lower flange 14 against movement relative to each other.
It will be understood that the invention is not to be limited to the exact construction shown and described, but that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims. | A vehicle window assembly having a window panel (11) movable in spaced relationship to and along a fixed guide (24) during raising and lowering movements. Interposed between the window panel and guide rod are guide means (13 and 15) that allow quick adjustment during the assembly of the vehicle body of the position of the window panel relative to body seals around the perimeter of the window opening. This quick adjustment is achieved through resilient retainer devices (32) having ratchet action engagement with the guide means 15 that controls the lateral spacing of the window panel relative to the guide rod. After the desired spacing is achieved through the quick adjustment devices, permanent fastening devices may be tightened to complete the installation procedure. | 4 |
BACKGROUND
1. Technical Field
The present disclosure generally relates to friction stir welding, and particularly, to a friction stir welding method using a joining tool without a mixing pin.
2. Description of Related Art
Friction stir welding is widely used to join aluminum alloy because it is simple to perform.
A metal structure of the stirred product can be constituently uneven, since the material of the stirred portion of the product plastically flows in the friction stir welding process. After treatment, the different areas, specifically the stirred and unstirred portions of the product, may exhibit different aspects, wherein the joining portion of the workpieces provides an unfavorable appearance. Despite product annealing, the difference of the joined portion persists. Therefore, this can not satisfy a product with the stirred surface presented as an outer surface.
Achievement of a favorable appearance in products obtained by friction stir welding remains a challenge.
Therefore, an improved friction stir welding method is desired to overcome the described limitations.
BRIEF DESCRIPTION OF THE DRAWINGS
The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout several views.
FIG. 1 is a schematic view of a joining tool used in an embodiment of a friction stir welding method of the disclosure.
FIG. 2 is a bottom view of the joining tool of FIG. 1 .
FIG. 3 is a bottom view of another joining tool.
FIG. 4 is a schematic view of a first workpiece and a second workpiece to be joined.
FIG. 5 is a schematic view showing the joining tool friction stirring the first workpiece and the second workpiece.
FIG. 6 is a schematic view of a third workpiece and a fourth workpiece to be joined.
FIG. 7 is a schematic view showing the joining tool friction stirring the third workpiece and the fourth workpiece.
FIG. 8 is a schematic view of a fifth workpiece and a sixth workpiece to be joined.
FIG. 9 is a schematic view showing the joining tool friction stirring the fifth workpiece and the sixth workpiece.
FIG. 10 is a schematic view showing the fifth workpiece and the sixth workpiece joined.
FIG. 11 is a schematic view of a seventh workpiece and an eighth workpiece to be joined.
FIG. 12 is a schematic view showing the joining tool friction stirring the seventh workpiece and the eighth workpiece.
FIG. 13 is a schematic view of the fifth workpiece and a sixth workpiece to be joined and a joining member.
FIG. 14 is a schematic view showing the fifth workpiece and the sixth workpiece joined.
DETAILED DESCRIPTION
Referring to FIG. 1 and FIG. 4 , a joining tool 10 is used to join a first workpiece 20 and a second workpiece 30 . The joining tool 10 is substantially cylindrical and includes a friction surface 11 . The friction surface 11 is substantially flat. The joining tool 10 defines a slot 13 in the friction surface 11 . The slot 13 may be spiral as shown in FIG. 2 , and may include a plurality of curved slots starting at a rotation axis of the joining tool 10 , as shown in FIG. 3 .
Referring to FIG. 4 , the first workpiece 20 includes a first treating surface 21 and a first joining surface 23 substantially perpendicular thereto. The second workpiece 30 includes a second treating surface 31 and a second joining surface 33 substantially perpendicular to the second treating surface 31 .
Referring to FIG. 4 and FIG. 5 , the first workpiece 20 and the second workpiece 30 abut against each other, thereby defining a joint line 29 . The first joining surface 23 contacts the second joining surface 33 , and the first treating surface 21 and the second treating surface 31 are on the same plane. The first workpiece 20 and the second workpiece 30 are positioned in place by a clamp (not shown). The friction surface 11 of the joining tool 10 resists the first treating surface 21 and the second treating surface 31 and corresponds to the joint line 29 . The joining tool 10 rotates along an axis thereof relative to the first workpiece 20 and the second workpiece 30 and moves along the joint line 29 . Thus, the joining tool 10 rubs and stirs surface layers of the first workpiece 20 and the second workpiece 30 , such that material of the first treating surface 21 of the first workpiece 20 and second treating surface 31 of the second workpiece 30 , adjacent to the joint line 29 , are rubbed and stirred. Heat generated by friction and stirring is transferred to the unstirred material adjacent to the first joining surface 23 and the second joining surface 33 . The joining tool 10 produces a local region of highly plasticized material such that material of the first workpiece 20 and the second workpiece 30 diffuse among each other. As such, the first workpiece 20 and the second workpiece 30 are joined.
In the joining method as disclosed, a rotation direction of the joining tool 10 is the same as an extending direction from a center to a periphery of the joining tool 10 . The joining tool 10 rotates at a high speed and moves at a low speed, and an end of the joining tool 10 extends slightly into the first workpiece 20 and the second workpiece 30 . A rotation speed S, moving speed V, and stirred depth H of the first workpiece 20 and the second workpiece 30 are determined by various factors, such as the material and thickness of the first workpiece 20 and the second workpiece 30 , and the size and material of the joining tool 10 , so long as the first workpiece 20 and the second workpiece 30 can be joined. In the illustrated embodiment, the first workpiece 20 and the second workpiece 30 are aluminum alloy plates; the rotation speed S is about 7000 rpm, the moving speed V is about 500 mm/min, and the stirred depth H is about 0.15 mm.
Referring to FIG. 1 , FIG. 6 and FIG. 7 , a third workpiece 40 and a fourth workpiece 50 joined by the joining tool 10 are shown. The third workpiece 40 includes a third treating surface 41 and a third joining surface 43 substantially perpendicular to the third treating surface 41 . The third workpiece 40 further includes an inclined connecting surface 45 joining the third treating surface 41 and the third joining surface 43 . The fourth workpiece 50 includes a fourth treating surface 51 and a fourth joining surface 53 substantially perpendicular to the fourth treating surface 51 . The fourth workpiece 50 further includes an inclined connecting surface 55 joining the fourth treating surface 51 and the fourth joining surface 53 .
The third workpiece 40 and the fourth workpiece 50 abut against each other, thereby defining a joint line 59 . The connecting surfaces 45 , 55 define a slot 49 . The third joining surface 43 contacts the fourth joining surface 53 . The third treating surface 41 and the fourth treating surface 51 are on the same plane. The third workpiece 40 and the fourth workpiece 50 are positioned in place by a clamp (not shown). The friction surface 11 of the joining tool 10 resists the third treating surface 41 and the fourth treating surface 51 and corresponds to the slot 49 . The joining tool 10 rotates along the axis thereof relative to the third workpiece 40 and the fourth workpiece 50 and moves along the joint line 59 . Thus, the joining tool 10 produces a local region of highly plasticized material such that the third workpiece 40 and the fourth workpiece 50 diffuse among each other. As such, the third workpiece 40 and the fourth workpiece 50 are joined. Some plasticized material flows in the slot 49 and fills the slot 49 , thus enhancing the joint strength of the third workpiece 40 and the fourth workpiece 50 .
In the joining method disclosed, a rotation direction of the joining tool 10 is the same as an extending direction from a center to a periphery of the joining tool 10 . The joining tool 10 rotates at a high speed and moves at a low speed, and an end of the joining tool 10 extends slightly into the third workpiece 40 and the fourth workpiece 50 . A rotation speed S, moving speed V, and stirred depth H of the third workpiece 40 and the fourth workpiece 50 are determined by various factors, such as the material and thickness of the third workpiece 40 and the fourth workpiece 50 , and the size and material of the joining tool 10 , so long as the third workpiece 40 and the fourth workpiece 50 can be joined. In the illustrated embodiment, the third workpiece 40 and the fourth workpiece 50 are aluminum alloy plates; the rotation speed S is about 7000 rpm, the moving speed V is about 500 mm/min, and the stirred depth H is about 0.15 mm.
Referring to FIG. 1 and FIG. 8 through FIG. 10 , a fifth workpiece 60 and a sixth workpiece 70 joined by the joining tool 10 are shown. The fifth workpiece 60 includes a fifth treating surface 61 and a fifth joining surface 63 facing the fifth treating surface 61 . The sixth workpiece 70 includes a sixth treating surface 71 and a sixth joining surface 73 facing the sixth treating surface 71 . However, unlike the previous workpieces, the fifth treating surface 61 and fifth joining surface 63 , and sixth joining surface 73 and sixth treating surface 71 are non-perpendicular, disposed with an angle formed therebetween.
During joining of the fifth workpiece 60 and the sixth workpiece 70 , the fifth workpiece 60 and the sixth workpiece 70 are arranged together and angled to each other, with the fifth joining surface 63 contacting the sixth joining surface 73 , and the fifth treating surface 61 and the sixth treating surface 71 perpendicular to each other. A joint line 69 is defined at the joining portion of the fifth workpiece 60 and the sixth workpiece 70 . The fifth workpiece 60 and the sixth workpiece 70 are positioned in place by a clamp (not shown). The friction surface 11 of the joining tool 10 resists the fifth treating surface 61 . The joining tool 10 rotates along the axis thereof relative to the fifth workpiece 60 and the sixth workpiece 70 and moves along the joint line 69 . Thus, the joining tool 10 produces a local region of highly plasticized material such that material of the fifth workpiece 60 and the sixth workpiece 70 diffuse among each other. As such, the fifth workpiece 60 and the sixth workpiece 70 are joined to form a product 300 .
In the joining method disclosed, a rotation direction of the joining tool 10 is the same as the extending direction from a center to a periphery of the joining tool 10 . The joining tool 10 rotates at a high speed and moves at a low speed, and an end of the joining tool 10 extends slightly into the fifth workpiece 60 and the sixth workpiece 70 . A rotation speed S, moving speed V, and stirred depth H of the fifth workpiece 60 and the sixth workpiece 70 are determined by various factors, such as the material and thickness of the fifth workpiece 60 and the sixth workpiece 70 , and the size and material of the joining tool 10 , so long as the fifth workpiece 60 and the sixth workpiece 70 can be joined. In the illustrated embodiment, the fifth workpiece 60 and the sixth workpiece 70 are aluminum alloy plates, the rotation speed S is about 7000 rpm, the moving speed V is about 500 mm/min, and the stirred depth H is about 0.15 mm.
An angle is defined by the fifth treating surface 61 and the sixth treating surface 71 , such that the joint line 69 is in a corner. That is, the joint line 69 is superposed to an edge line. As such, the joint line 69 is hidden. The angle defined by the fifth treating surface 61 and the sixth treating surface 71 may be any degree other than 0° and 180°. In the illustrated embodiment, the angle is about 90°.
Further, an assisting member 200 can be provided to resist the sixth workpiece 70 . The assisting member 200 includes a first end surface 201 and a second end surface 203 substantially perpendicular to the first end surface 201 . The first end surface 201 of the assisting member 200 resists the sixth treating surface 71 of the sixth workpiece 70 and the second end surface 203 of the assisting member 200 is on the same plane as the fifth treating surface 61 of the fifth workpiece 60 .
With the assisting member 200 , the friction and stirred area increases, as does the friction heat. The increased heat is transmitted to the fifth workpiece 60 and the sixth workpiece 70 to enhance connection therebetween.
In the embodiment, after the first workpiece 20 is joined to the second workpiece 30 , the third workpiece 40 is joined to the fourth workpiece 50 , and the fifth workpiece 60 is joined to the sixth workpiece 70 , surface layers adjacent to the treating surfaces 21 , 31 , 41 , 51 , 61 , 71 may be removed. That is, material with a changed metal structure is removed and material with unchanged metal structure is exposed. Therefore, a product formed by the above described friction stir welding method can provide a favorable appearance, even if subsequent treatment, such as an anodic process.
Referring to FIG. 11 and FIG. 12 , a seventh workpiece 80 and an eighth workpiece 90 joined by the joining tool 10 are shown. The seventh workpiece 80 includes a seventh treating surface 81 , a seventh joining surface 83 facing the seventh treating surface 81 , and a connecting surface 85 connecting the seventh treating surface 81 and the seventh joining surface 83 . The connecting surface 85 is substantially perpendicular to the seventh treating surface 81 . The eighth workpiece 90 includes an eighth treating surface 91 and an eighth joining surface 93 facing the eighth treating surface 91 . However, unlike the previous workpieces, the seventh treating surface 81 and seventh joining surface 83 , and the eighth joining surface 93 and eighth treating surface 91 are non-perpendicular, disposed with an angle formed therebetween.
When joining of the seventh workpiece 80 and the eighth workpiece 90 , the seventh workpiece 80 and the eighth workpiece 90 are arranged together and angled to each other. The seventh joining surface 83 contacts the eighth joining surface 93 , and the seventh treating surface 81 and the eighth treating surface 91 are perpendicular to each other. A joint line 89 is defined at the joining portion of the seventh workpiece 80 and the sixth workpiece 90 . The seventh workpiece 80 and the eighth workpiece 90 are positioned in place by a clamp (not shown). The friction surface 11 of the joining tool 10 resists the seventh treating surface 81 . The joining tool 10 rotates along the axis thereof relative to the seventh workpiece 80 and the eighth workpiece 90 and moves along the joint line 89 . Thus, the joining tool 10 produces a local region of highly plasticized material of the seventh workpiece 80 and the eighth workpiece 90 which diffuse among each other. As such, the seventh workpiece 80 and the eighth workpiece 90 are joined.
After the seventh workpiece 80 is joined to the eighth workpiece 90 , surface layers adjacent to the treating surfaces 81 , 91 may be removed. Therefore, product formed by the above described friction stir welding method can provide favorable appearance, even if subsequent treatment, such as an anodic process. When a removed layer of the eighth workpiece 90 is thinner than that of the seventh workpiece 80 , the joint line 89 may be at a corner, that is, superposed to an edge line of the joined seventh workpiece 80 and the eighth workpiece 90 , thus hidden.
The workpieces 20 , 30 , 40 , 50 , 60 , 70 , 80 , 90 may be a material with low melting point, such as aluminum, aluminum alloy, copper alloy, or rubber, and be of any shape. Material of the joining tool 10 is a critical factor determining material of the workpieces 20 , 30 , 40 , 50 , 60 , 70 , 80 , 90 . Increased melting point of the joining tool 10 allows a higher melting point of the material of the workpieces 20 , 30 , 40 , 50 , 60 , 70 , 80 , 90 . The melting point of the joining tool 10 must exceed that of the workpieces 20 , 30 , 40 , 50 , 60 , 70 , 80 , 90 . Joining portions of the workpieces may be point, line or surface.
The disclosed joining method provides products with lower requirements for joint strength. If a product with strong joint strength is desired, the workpieces may define a slot at the joining portion in which a joining member with a melting point lower than the workpieces is received. The joining member is disposed away from the rubbed and stirred portion of the workpieces, thus the joining member may transmit heat to material far away from the rubbed and stirred portion. Therefore, a joining strength may be enhanced. A joining member provided to join the fifth workpiece 60 and the sixth workpiece 70 is discussed as follows.
Referring to FIG. 13 and FIG. 14 , the fifth workpiece 60 defines a first slot 67 at the fifth joining surface 63 and the sixth workpiece 70 defines a second slot 77 at the sixth joining surface 73 . When the fifth workpiece 60 and the sixth workpiece 70 are arranged together, the first slot 67 and the second slot 77 cooperatively form a receiving slot (not labeled). To join the fifth workpiece 60 and the sixth workpiece 70 , a joining member 400 is positioned in the receiving slot. When rubbing and stirring the fifth treating surface 61 of the fifth workpiece 60 , heat is transmitted to the receiving slot, and the material of the joining member 400 becomes plasticized before the fifth workpiece 60 and the sixth workpiece 70 because the joining member 400 has a lower melting point. Heat transmitted adjacent to the receiving slot may not raise a temperature adjacent to the receiving slot to that of the fifth workpiece 60 and the sixth workpiece 70 , while raising the temperature to the melting point of the joining member 400 . Thus, material of the joining member 400 flows in the receiving slot to join with the fifth workpiece 60 and the sixth workpiece 70 to enhance the joining strength of the fifth workpiece 60 and the sixth workpiece 70 .
Alternatively, the receiving slot may be only defined in one of the fifth workpiece 60 and the sixth workpiece 70 . A joining member 400 may be positioned in each of the fifth workpiece 60 and the sixth workpiece 70 . The joining member 400 may be solder.
In the disclosed friction stir welding methods, only the joining portions of the workpieces need be machined, such that the joining tool 10 is small, with a correspondingly low driving force thereof required. Equipment applying the joining tool 10 to friction stir welding is simple and low cost.
The joining tool 10 may be applied in ordinary machining centers (not shown), whereby workpieces may be machined and joined at the same machining center. As such, the workpieces need only be clamped once, thus improving machining efficiency and precision. In addition, no special machine is needed. Furthermore, the friction stir welding method can join workpieces with complex joining surfaces.
Finally, while various embodiments have been described and illustrated, the disclosure is not to be construed as being limited thereto. Various modifications can be made to the embodiments by those skilled in the art without departing from the true spirit and scope of the disclosure as defined by the appended claims. | A friction stir welding method includes providing a joining tool including a friction surface; providing a first workpiece and a second workpiece; arranging the first workpiece and second workpiece in position with a first joining surface abutting a second joining surface, a friction surface of a joining tool resisting at least one of the first treating surface and the second treating surface; positioning, rotating and moving the joining tool to rub and stir at least one of the first workpiece and the second workpiece, thus plasticizing at least part of the first workpiece and the second workpiece to join the first workpiece and the second workpiece. | 1 |
FIELD OF THE INVENTION
[0001] The present invention relates to a device and a method for cooling tool holders with shrink fit chucks.
BACKGROUND OF THE INVENTION
[0002] Tool holders with shrink fit chucks come in all variations. They serve to clamp piping, turning, milling, reaming and grinding tools and the like by a thermally induced shrinking process. Usually, such shrink fit chucks are thermally heated by inductive shrinking devices, as a result of which the inside diameter of the shrink fit chuck is enlarged. With the inside diameter enlarged, a tool to be clamped is inserted into the shrink fit chuck, with the ratio of the inner diameter of the shrink fit chuck to the shaft diameter of the tool designed such that, on subsequent cooling of the shrink fit chuck, the tool is firmly clamped by the shrink fit chuck and cannot rotate.
[0003] To accelerate cooling, cooling devices with ring-like heat sinks are often used, with the heat sink having an internal geometry adapted to the shrink fit chuck and being flowed through by a coolant. The disadvantage of these heat sinks is that adapting them to different shrink fit chuck dimensions is very difficult and often thermally ineffective and therefore a plurality of heat sinks must be kept available for the different shrink fit chucks.
[0004] For the purpose of avoiding this disadvantage, direct cooling devices are known that usually employ a coolant along with additives to prevent rusting. The shrink fit chuck together with the inserted tool is introduced into a housing, which is then closed water-tight in order that it may be cooled by the coolant. To be sure, the cooling device is highly versatile for use with all kinds of shrink fit chucks, but such a cooling device is unsuitable for cooling several shrink fit chucks in direct succession, especially in an automated process.
SUMMARY OF THE INVENTION
[0005] An object of the present invention is to provide a device for cooling tool holders with shrink fit chucks, said device being versatile for use with all kinds of tool holders while simultaneously facilitating more efficient cooling of several tool holders, particularly in direct succession.
[0006] According to an aspect of the present invention, the device for cooling tool holders with shrink fit chucks, which are accommodated in a tool holder receptacle, comprises means for spraying the tool holder with coolants (e.g., in liquid form), means for transporting the tool holder receptacle, and means for activating the means for cooling and the means for transporting. In this connection, the means for transporting are adapted for simultaneously transporting several tool holder receptacles through the device in succession.
[0007] The means for transporting the tool holder receptacles has an advantage of ensuring that not only one tool holder receptacle but several tool holder receptacles can be transported simultaneously in succession through the device and thus it is no longer necessary as it was before to await the cooling process at one tool holder before a further tool holder can be transported to such a cooling device by hand. The inventive cooling device is therefore much more efficient and allows the cooling process for several successive tool holders to be automated.
[0008] Advantageously, the means for transporting transports the tool holder receptacle can be substantially horizontal through the device, as that keeps down the design effort.
[0009] The means for activation can be adapted such that the device can be operated semi-automatically, and preferably fully automatically. A semi-automatic operation can be made possible, for example, in such a manner that a corresponding push-button for operation by the operating personnel is provided which is pressed after the tool holder receptacle with hot tool holder has been introduced into the cooling device, as a result of which the means for transporting and the means for cooling are activated. A fully automatic operation, in turn, could be facilitated by appropriate sensor technology that detects the introduction of a tool holder receptacle into the cooling device.
[0010] The means for transporting the tool holder receptacles through the device can be in an essentially linear first transport direction, as a result of which the device can have a particularly slim structure. If the device needs to be more compact, it is advantageous if the means for transporting the tool holder receptacles through the device in an essentially circular first transport direction.
[0011] If cooling liquids are to serve as coolant, it is furthermore advantageous to provide means for drying the cooled tool holder and to implement the means for cooling and drying in isolated areas of the device separate from each other as cooling station and drying station. As a result, the cooling efficiency of the device increases, because a tool holder is cooled in the cooling station at the same time as a tool holder can be dried in the drying station.
[0012] In an embodiment of the present invention, means of detecting temperature are provided, with the aid of which the temperature of the tool holder can be determined and, in accordance with the temperature observed, the means for activation can be controlled, such that the means of cooling can selectively release the coolant.
[0013] In another embodiment, the device can have a parking station and possibly a transfer station to the parking station, in which tool holder receptacles with cooled or cooled and dried tool holders are stored prior to removal from the cooling device. This parking station makes it possible for several tool holders to be cooled in direct succession by the cooling device, even when they are not removed from the cooling device by the operating personnel directly.
[0014] In the same measure, the cooling station can be preceded by a feed station, in which one or more tool holder receptacles can be stored temporarily before cooling.
[0015] In this regard, the transport directions in the feed station and/or the parking station can be different from the first transport direction, because that enables the cooling device to be kept very compact. It is contemplated that these two transport directions can be flexibly adjusted to the local conditions of the installation site of the cooling device.
[0016] In a particularly simple manner, the means for transporting can be realized by one or more chains or conveyors, which have dogs for the tool holder receptacles. On the other hand, gripper devices can also be provided, which are arranged to the side or above the transport direction and either are traversable in the transport direction or one gripper device each is assigned to one station, and two, with respect to the transport direction, neighboring gripper devices each forwarding one tool holder receptacle.
[0017] To essentially suppress escape of coolant, which usually contains water and rust inhibitor, or its vapors into the vicinity of the cooling device, it is preferable for at least the cooling station, especially the drying station as well, to have appropriate means of shielding. Such shielding means can consist of gas-tight and water-tight containers. Where applicable, appropriate waste and return means for catching the coolant can be provided on the lower side of the container.
[0018] Accordingly, suitable means for extracting vapors can be attached to the container walls as well.
[0019] For the purpose of facilitating transporting of the tool holder receptacles through such a shielded device, openable shielding doors can be provided at various points, said doors being closed when the device is in operation and capable of being opened during guiding. This allows the container to always remain at the cooling device. In particular, such doors can be provided before and after the cooling station, after the drying station and after the transfer station.
[0020] The cooling equipment as well as the drying agent can be designed as a ring with several spray elements, which are vertical relative to the tool holder and can be raised and lowered essentially concentrically with this. This makes for particularly uniform cooling and drying of the tool holder. To control the cooling and drying equipment in their vertical motion, suitable sensors can be provided that detect the contour of the tool holder.
[0021] Alternatively, the cooling and drying equipment can also be designed as spray elements, which, relative to the first transport direction, are arranged on both sides of the tool holder. This variant has a very simple design. The coolant spray elements can be arranged radially on the tool holder to optimize the cooling effect. In this variant, too, the spray elements can be traversed vertically or several spray elements can be arranged vertically above each other.
[0022] Accordingly, the inventive cooling method includes the cooling of a tool holder with a coolant and the transporting of one or more tool holder receptacles simultaneously in succession, with the method being performed with a device in accordance with the above description. In this regard, the coolant can be a liquid coolant, which is sprayed onto the tool holder, and, after the cooling step, a drying step occurs, in which the tool holder is sprayed with compressed air. The compressed air creates a kind of wiping effect that wipes, and thus dries, the coolant from the tool holder(e.g., vertically downwards).
[0023] The tool holder receptacles can be transported either continuously without interruption through the device or periodically, such that for every period, at least one tool holder receptacle is located in a station of the device and, in between periods, at least one tool holder receptacle is transported from one station to the next one in succession. The shielding doors between individual stations can be opened in between periods, with especially only those shielding doors being opened which the tool holder receptacles have passed. For this purpose, it is sensible to provide appropriate sensors, which determine whether or not the tool holder receptacles are about to pass shielding doors.
[0024] In an alternative embodiment of the present invention, the device for cooling tool holders with shrink fit chucks, which are accommodated in a tool holder receptacle, comprises means for spraying the tool holder with coolants(e.g., in liquid form), means for transporting the tool holder receptacle and means for activating the means for cooling and the means for transporting. In this regard, the means for transporting are adapted for simultaneously transporting several tool holder receptacles through the device in succession. As has already been explained, the means for transporting the tool holder receptacles can ensure that not just one tool holder receptacle but several tool holder receptacles can be simultaneously transported through the device in succession and thus it is no longer necessary as it was before to await the cooling process in one tool holder until a further tool holder can be transported by hand to such a cooling device. The inventive cooling device is therefore much more efficient and allows the cooling process for a succession of several tool holders to be automated. Advantageously, the means for transporting transports the tool holder receptacle essentially vertically through the device, as the design effort can also be kept low in this way.
[0025] Further advantages, characteristics and features of the present invention become clear from the following description in connection with the figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is a first embodiment of the present invention schematically in a vertical cross-sectional illustration;
[0027] FIG. 2 is a device in accordance with FIG. 1 together with a shrinking device in a perspective overall view;
[0028] FIG. 3 is a second embodiment of the present invention schematically in a vertical cross-sectional illustration; and
[0029] FIG. 4 is the device in accordance with FIG. 3 , together with a shrinking device in a perspective overall view.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0030] The inventive cooling device 1 shown in a purely schematic plan view in FIG. 1 comprises a container 2 , inside of which are arranged a feed station 3 , a cooling station 4 , a drying station 5 , and a transfer station 6 . Outside the container 2 connecting to the transfer station 6 is a parking station 7 , which is capable of receiving two tool holder receptacles 8 a , 8 b . At the feed station 3 and the transfer station 6 are doors 9 , 10 , which are provided for closing the container 2 during operation of the cooling device but which can however be opened for loading and transferring the tool holder receptacles 8 a , 8 b , 8 c , etc.
[0031] For transporting the tool holder receptacles 8 a , 8 b , 8 c , etc. inside the cooling device 1 is provided a means for transporting 11 in the form of a chain with dogs. Inside the container 2 , the chain 11 runs in a first transport direction and branches inside the transfer station 6 into a transport direction perpendicular to that. In this way, as clearly shown in FIG. 2 , the cooling device is optimally adapted geometrically to a shrinking device 12 of known type, as a result of which both devices 1 , 12 can be arranged so as to save as much space as possible.
[0032] During operation of the cooling device 1 , a tool holder receptacle 8 g , in which a tool holder 13 , which is hot due to the shrinking process, and the tool 14 clamped therein, is transported through the door 9 of the feed station 3 . Door 9 is either opened by actuating the push button of a corresponding opening mechanism or opening occurs independently by means of suitable sensor detection. After the door 9 has been closed again either at the press of a button or automatically, the tool holder receptacle 8 f is transferred at the press of a button or automatically into the cooling station 4 by means of the chain, although if another tool holder receptacle 8 c happens to be in the transfer station 6 , door 10 opens at the same time and this tool holder receptacle 8 c is transferred into the parking station 7 . After the door 10 has been closed at the press of a button or automatically, the container 2 on this side too is sealed off, with the container 2 sealed such that no coolant or coolant vapor can escape outside into the vicinity of the cooling device 1 , and the cooling process can begin.
[0033] For this purpose, as with all previous and following actions, the action can be started at the press of a button or automatically, which is why no further mention is made of this action. For the cooling process inside the cooling station 4 , coolant spray nozzles 15 are arranged radially such that they point towards the tool holder, said nozzles cooling the tool holder 13 by spraying with coolant. To optimize the cooling process, a temperature sensor (not shown) may be provided that detects the temperature of the tool holder 13 and suitably controls spraying with coolant. Furthermore, especially in the case of long tool holder receptacles 13 , several coolant spray nozzles 15 can be provided vertically above each other, or such that the coolant spray nozzles 15 are arranged in a plane and can be vertically raised and lowered together.
[0034] After the cooling process has been completed, the tool 14 is clamped firmly against rotation in the tool holder 13 , the tool holder receptacle 8 e is transferred from the cooling station 4 into the drying station 5 where laterally attached compressed-air jets 3 , 6 blow the coolant off the tool 14 and tool holder, such that these are dried. Following completion of drying, the tool holder receptacle 8 d is transferred into the transfer station 6 and, after opening of the door 10 , into the parking station 7 , where it can be removed by the operating personnel.
[0035] All processes just described occur periodically in the cooling device 1 , i.e. while tool holder receptacle 8 a , 8 b , 8 c , etc. is in one of the stations 3 , 4 , 5 , 6 inside the container 2 of the cooling device 1 , no further transfer of tool holder receptacles 8 a , 8 b , 8 c , etc. takes place between the individual stations 3 , 4 , 5 , 6 , 7 .
[0036] FIGS. 2 and 3 show further purely schematic embodiments of the inventive cooling device 20 . This also has a closed container 21 , in whose interior is a cooling station 22 , a drying station 23 and a transfer station 24 . Transporting within the container 21 is effected by means of a turntable 25 , which, over its axis of rotation 26 , has continuous walls 27 , 28 arranged at right angles to each other like a cross, each of which shields the individual stations 22 , 23 , 24 from each other and the cooling station 22 and the transfer station 24 from the feed station 29 . This ensures that cooling liquid and vapor from the cooling station 22 cannot be transferred into the other stations or the vicinity of the cooling device 20 during the cooling process.
[0037] The cooling station 22 and the drying station 23 contain an arrangement of ring elements 30 , 31 on vertical linear guides 32 , 33 , which, at regular distances, have inwardly pointing coolant spray nozzles 34 or compressed-air spray nozzles 35 . By means of the linear guides 32 , 33 , the rings 30 , 31 can be raised and lowered concentrically with the tool holders 36 and the tools 37 , and thus the cooling process or the drying process can be performed optimally.
[0038] During operation of the cooling device 20 , a tool holder receptacle 38 a , in which is located a tool holder 36 with shrunk fit tool 37 , is transferred to the feed station 29 on the turntable 25 . Thereafter, the turntable is rotated in 90″ increments into the cooling station 22 , from there into the drying station 23 and, after drying has taken place, into the transfer station 24 . From the transfer station 24 , the tool holder receptacle 38 d is transferred by suitable means for transporting 39 , after door 40 has opened, into the parking station 41 , with, for the sake of simplicity in FIG. 4 , only one tool holder 38 e being illustrated compared with the two tool holder receptacles 38 e , 38 f shown in FIG. 3 . Thus, the tool holder receptacles 38 a , 38 b , 38 c , etc. pass successively from an established shrinking device 42 and periodically through the cooling device 20 and can be removed from the parking station 41 by the operating personnel.
[0039] From the above description, it has become clear that, with the help of the inventive cooling device 1 , 20 and the inventive method for cooling a tool holder with shrink fit chucks, an especially efficient, above all fully automatable cooling can be achieved, which also permits cooling of several tool holders 13 , 36 in succession. In this regard, the cooling device 1 , 20 is not only very economical but it can be designed such that it is perfectly adapted to local spatial conditions and existing shrinking devices 12 , 42 .
[0040] The above description is considered that of the preferred embodiment(s) only. Modification of the invention will occur to those skilled in the art and to those who make or use the invention. Therefore, it is understood that the embodiment(s) shown in the drawings and described above are merely for illustrative purposes and not intended to limit the scope of the invention, which is defined by the following claims as interpreted according to the principles of patent law, including the doctrine of equivalents. | The invention relates to a method and a device ( 20 ) for cooling tool holders comprising shrink fit chucks, said tool holders beings received in a tool holder seat. The invention provides an especially efficient and above all completely automatable cooling system which allows a successive cooling of a plurality of tool holders ( 36 ). The cooling device ( 20 ) is very economical and can be shaped in such a manner as to be perfectly adapted to the space available and to already present shrink-fit devices ( 42 ). | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to a device for anchoring a probe in a well by spreading mobile anchorage arms which are applied against the walls.
An anchorage device of the aforementioned type as described in, for example, French Patent No. 2,548,727 and corresponding to U.S. Pat. No. 4,616,703, wherein at least one spring is provided, with a rod being driven in a translatory motion by expansion of the spring. Means are provided for transforming the translational movement of the rod into a pivoting movement of the anchorage arm, and means are provided for intermittently immobilizing the rod in a position in which the spring is compressed, with the immobilization means comprising a bolt adapted to be engaged in a radial recess of the rod in the compressed position of the spring and hydraulic means for moving the bolt, of an anchorage arm, and means are provided for intermittently immobilizing the rod in a position in which the spring is compressed, with the immobilization means comprising a bolt adapted to be engaged in a radial recess of the rod in the compresed position of the spring and hydraulic means for moving the bolt.
The hydraulic means may comprise a cavity formed in the body of the apparatus, a head fast with the bolt in translation and adapted to slide into the cavity, and a hydraulic circuit for intermittently applying unequal pressures to the two opposite faces of the head, with one of the two pressures being equal to the pressure prevailing in the well at the chosen depth where the apparatus is immobilized. The application of the two unequal pressures is provided, for example, by means of an electrovalve.
Since the device is most often used at a depth of several hundred meters where the pressure is high, the force to which the bolt is subjected because of the differential pressure applied to the piston is considerable and permits a very reliable and very clean tripping of opening of the arms.
However, it has been discovered that accidental tripping could occur although the electrovalve is in a closed position and isolates the bolt from the well pressure. This can be attributed to sealing defects which place the hydraulic fluid of the bolt control circuit unexpectedly at an equal pressure with the pressure prevailing in the well and causes the bolt to recoil.
SUMMARY OF THE INVENTION
An object of the present invention resides in providing a new anchorage device for anchoring a probe and a well by spreading mobile anchorage arms against walls of the well which avoids, by simple means, an untimely tripping of each anchorage arm.
The hydraulic means, as in the embodiment of the above-described French patent includes a cavity formed in the body of the apparatus, with a head being fast with the bolt in translation being adapted to slide in and with a cavity, the section of the head being greater than that of the bolt, and a hydraulic circuit for applying a variable pressure to the head of the bolt.
A pressure application means is provided for permanently applying to the bolt a pressure equal to the pressue prevailing in the well and to the head fast with the bolt an opposite pressure which may vary between a first pressure whose value is sufficient to move the bolt towards its engagement position in the radial recess of the rod, and a second fairly low value so that the bolt is pushed towards its released position.
The pressure application means comprise, for example, a duct opening into the cavity on the side of the head opposite the bolt and switching means for selectively applying to the head the first pressure or the second pressure.
The pressure application means comprise a first and a second chamber of different sections formed in the body of the probe, a first and a second piston of different sections adapted respectively to the section of the first and second chambers, with the first smaller section piston being permanently exposed to the pressure in the well, and the second chamber in which the second piston moves communicating with said duct, which is connected intermittently through an electro valve to a volume where a pressure prevails less than the pressure prevailing in the well.
With such an arrangement, any possible leak which would place the fluid in the duct at a pressure identical to that which prevails in the well can only further increase the resultant forces applied to the bolt and head assembly and which hold it in the locked position and any unexpected tripping becomes impossible.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects, features, and advantages of the anchoring device of the present invention will become more apparent from the following description when taken in connection with the accompanying drawings which show, for the purpose of illustration only, one embodiment in accordance with the present invention, and wherein:
FIG. 1 is a partial longitudinal cross-sectional view of a probe with the anchorage device of the present invention in the locked position holding an anchorage arm closed;
FIG. 2 is a partial cross-sectional detailed view of the pressure application means of the present invention in a position for locking the anchorage arm in the closed position;
FIG. 3 is a partial longitudinal cross-sectional view of an anchorage device in accordance with the present invention which has been tripped for moving the anchorage arm away; and
FIG. 4 is a partial cross-sectional detailed view of the pressure application menas in a position for tripping the anchorage bolt of the anchorage device of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings wherein like reference numerals are used throughout the various views to designate like parts and, more particularly to FIGS. 1 and 2, according to these figures, an anchorage device of the present invention is associated with a tubular probe generally designated by the reference numeral 1 having an upper part generally designated by the reference numeral 2 and a lower part generally designated by the reference numeral 3, with the tubular probe 1, upper part 2, and lower part 3 being made fast with each other by several bars 4.
The measuring apparatus formed, for example, of geofoams, is contained in a compartment 5 in the lower part 3 of the probe 1 and is connected to a multi-function cable supporting the probe 1 by electric conductors (not shown) passing, for example, inside the bars 4. One of the bars 4 comprises a pin 6 about which an anchorage arm 7 may pivot. A first end of a first operarting arm 9 is articulated on a pin 8 fixed to the anchorage arm 7 at a certain distance from the pin 6. A first end of a second operating arm 11 is articulated on a pin 10 fast with another bar 4, with the second ends of the two operating arms 9, 11 being adapted to pivot with respect to a common pin 12. A first end of a third operating arm 13 is pivotally mounted on the common pin 12.
The anchorage device also comprises a rod 14 having a recess 15 in the bottom of which is fixed an articulation pin 16 for the second end of the third operating arm 13. The rod 14 may slide in a cylindrical guide housing 17 formed in the axis of the body 18 of the probe 1.
A helical spring 19 bearing by a first end on the body of the probe 1 and by a second end on a shoulder 20 of rod 14 exerts on the latter rod 14 a force tending to cause the rod 14 to leave a guide housing generally designated by the reference numeral 17. An axial channel 21 is formed in the upper part of rod 14 and communicates with a radial bore 21A opening externally of the body 18.
The upper part of guide housing 17 is extended by a chamber 22 of larger section containing a hydraulic liquid. A piston 23 formed of two parts of different sections 51 and 52 is adapted to slide freely and sealingly in chamber 22 and the upper part of the guide housing 17, under the action of the possible pressure difference between the pressure of the hydraulic liquid and the pressure prevailing in the well, so as to cancel out this pressure difference.
The device further comprises a bolt 24 having a head 25 of larger section movable inside a cylindrical cavity 26 formed radially in body 18 of the probe 1, between a retracted position in which the bolt 24 is entirely retracted inside said body 18 and an extended position in which the bolt 14 projects inside the guide housing 17. A recess 27 (FIGS. 3, 4) is formed radially in rod 14 for bolt 24. It opens into the central channel 21 of rod 14 and thus a pressure Pe, prevailing in the well, is permanently applied to the bolt 24 on the rod 14 side. Cavity 26 is closed outwardly by a plug 28. The dimensions of the control arms and the position of the articulation pins 8, 10, 12 and of housing 27 are chosen so that, when the anchorage arm 7 is in the closed position along the body of the probe 1, the helical spring 19 is tensioned and the bolt 24 is engaged in the recess 27.
The pressure application means permitting unlocking of arm 27 are disposed in a housing generally designated by the reference numeral 29 of the body 18, the detail of which is shown most clearly in FIGS. 2 and 4, with the pressurre application means comprising a tubular added piece 30 of a section adapted to that of chamber 22 and fixed therein by threading. Piece 30 comprises a cylindrical inner cavity 31 closed on the piston 23 side and open on the opposite side. Chamber 22 is extended by another chamber 32 of larger section and in chamber 32 is disposed an electrovalve 33 having a threaded connection 33A which is threaded on to the tubular piece 30 at its open end. The electrovalve 33 comprises a mobile piston L whose section is adapted to that of cavity 31.
A circular groove 34 is formed in the wall of the tubular piece 30 about piston L. A first longitudinal duct 35 causes the groove 34 and chamber 22 to communicate with each other between the free piston 23 and the closed end of the tubular piece 30. Through a second duct 36 formed longitudinally in the wall of body 18, groove 34 communicates with cavity 26 where the head 25 of the bolt moves. A second circular groove 37 is formed in the inner wall of chamber 22 about the added piece 30. A first radial bore in the wall of the added piece 30 causes the inner cavity 31 to communicate with the groove 37. A second groove 39, in the external wall of the body 18 causes the groove 37 to communicate with the outside of the probe, with the second bore 39 being closed by a threaded plug 40. Two other radial bores 41 and 42 are also formed in the wall of the body 1, and at a first end, thereof open externally of the body 1 and at a second end thereof, respectively closed by two threaded plugs 43, 44. At their opposite end, they communicate respectively with the two parts of chamber 22 on each side of the free piston 23, the first on the added piece 30 side, the second on the same side as channel 21 in rod 14.
Seals 44, 45, 46, 47, 48, 49 are disposed respectively about piston P, the added piece 30, piston 23, rod 14 and bolt 24 for providing sealed sliding thereof.
The electrovalve 33 is connected by conductors 50 to a transmission line included in the electric supply and support cable (not shown). In the rest position, the piston L is in an extended position (FIGS. 1, 2) and isolates the inside of cavity 31 from groove 34.
When the electrovalve 33 is activated, piston L recoils sufficiently (FIGS. 3, 4) so as to cause cavity 31 to communicate with groove 34 and so with duct 36.
When the electrovalve 33 is in a rest position, the external pressure Pe is exerted through channel 21 in rod 14 and recess 27 on the smaller section face S2 of the free piston 23 and on the bolt 24 of section S3.
The hydraulic liquid pressure in chamber 22 on the side of the free piston 23 opposite rod 14 is reduced in the ratio S1/S2. This reduced hydraulic pressure is transmitted into cavity 26 through ducts 35 and 36 and is exerted on head 29 fast with the bolt 24, whose section is S4. The resultant force Fr applied to bolt 24 may be expressed by the following relationship. ##EQU1##
The different sections S1 to S4 are chosen so that the force Fr is centripetal and results in driving the bolt into recess 27 (FIGS. 3, 4) of the rod 14 in the closed position of the anchorage arm 7.
With the probe on the surface and the electrovalve 33 closed so as to isolate the inner chamber 31, the threaded plug 40 is opened so as to drain the oil which it may contain and it is filled with a low pressure p (atmospheric pressure for example). Through channel 42 a vacuum is created in the portion of chamber 22 opposite the added piece 30.
Oil is injected into chamber 22 through duct 41 in a sufficient amount to fill ducts 35, 36, groove 34 and cavity 26 and to drive out the air.
The resultant force Fr exerted on the bolt 24 in accordance with the above relationship (1) is sufficient to push the bolt 24 against rod 14. When the anchorage arm 7 is brought to a closed position against the wall of the body (FIG. 7) by compressing the helical spring 19, the rod 14 is caused to retract inside its guide housing 17 as far as the reset position where bolt 24 is driven into the recess whereby the anchorage arm 7 is locked.
To check the locking of the anchorage arm 7, a relatively high hydraulic pressure may leasft momentarily be injected into chamber 22 and cavity 26.
The probe is then lowered into the well and, as it descends, the external pressure increases, with a recoil of the free piston 23 inside chamber 22 under the action of this pressure which is applied thereto through the axial channel 21 making it possible at all times to equalize the pressure of the hydraulic liquid contained in chamber 22 with the pressure prevailing in the well.
When the probe 1 has reached the chosen depth at which it is to be anchored, the electrovalve 33 is actuated so that piston P recoils (FIGS. 3, 4) and places ducts 35, 36 in communication with the inner cavity 31 at a very low pressure p. The bolt 24 is subjected on the axial channel 21 side to a force equal to Pe53 and, on the opposite side, to a force equal to P54. The resultant is a centrifugal force sufficient to overcome the friction forces of the bolt 24 in its recess 27 of the rod 14 and drive it to its retracted position (FIGS. 3, 4).
Rod 14 is released and, under the action of the helical spring 19, is pushed outwardly of the guide housing 17. The pivoting of the control arm 9, 11, 13 resulting from this movement results in causing the anchorage arm 7 to pivot and, when it is applied against the wall, in pressing the probe 1 against the opposite wall of the well whereby the apparatus contained in the probe 1 may then be used.
One of the oppositely acting pressures exerted on the bolt 24 and the head 25 is constantly equal to and the other proportional to the external pressure and possible leaks cannot change the direction of the resultant of the forces which hold them in the locked position.
Without departing from the scope of the invention, the same hydraulic system may be used for controlling the simultaneous unlocking of several anchorage arms such as the anchorage arm 7. | A device is provided for anchoring a probe in a well by remote control spreading, from the surface, of at least one anchorage arm kept in a closed position by a retractable bolt engaged in a rod connected to the anchorage arm by links. The external pressure is exerted permanently on the bolt and the bolt is fast with a head movable in a cavity. A pressure is applied to the head which is proportional to the external pressure which holds the bolt locked in the rod or a much lower pressure resulting in release of the bolt. | 4 |
RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application No. 61/019,104, entitled DISPLAY MOUNT WITH POST-INSTALLATION ADJUSTMENT FEATURES, filed Jan. 4, 2008, and is a Continuation-in-Part of U.S. Design Application No. 29/319,787, entitled TWO-RAIL MOUNT FOR ELECTRONIC DISPLAY, filed Jun. 15, 2008, and U.S. Design Application No. 29/319,788, entitled SHELF ATTACHMENT FOR ELECTRONIC DISPLAY MOUNT, filed Jun. 15, 2008, and U.S. Design Application No. 29/319,789, entitled WALL INTERFACE FOR DISPLAY MOUNT, filed Jun. 15, 2008, and U.S. Design Application No. 29/319,790, entitled TILT ADJUSTABLE DISPLAY INTERFACE BRACKET, filed Jun. 15, 2008, and U.S. Design Application No. 29/319,792, entitled FIXED TWO-RAIL MOUNT FOR ELECTRONIC DISPLAY, filed Jun. 15, 2008, each of said applications hereby fully incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates generally to mounting devices for electronic displays and more particularly, to devices for mounting flat-screen electronic displays and associated peripheral devices to vertical surfaces.
BACKGROUND OF THE INVENTION
Flat-screen electronic display devices such as LCD and plasma displays are popular among consumers. A highly desirable feature that has, in large part, led to the popularity of these displays is the attractive aesthetic of a thin display device that can be mounted on a wall so as to resemble a framed photograph or painting.
Accordingly, numerous mounting devices and structures have been developed for mounting flat panel electronic displays to walls and other elements of structures. A typical drawback of these previous mounting devices, however, is that strict attention must be paid during installation of the mounting device to ensure that the display will be mounted in the optimal position on the structure and that the display will be level or aligned with the structure. Even a very small error in positioning of the mounting device during installation can result in a highly noticeable misalignment of the display when mounted, thereby detracting significantly from the aesthetics of the display installation.
Due to the location of structural elements such as wall framing members, it is often difficult to position a display mount in precisely the position desired on a wall surface. Further, fasteners used to fasten the mounting device to the wall typically lack precision and may shift during the installation process, leading to misalignment of the mounting device.
What is needed in the industry is a mounting device for electronic display devices that enables precision post-installation adjustment of mount and display device position relative to the structure upon which they are mounted.
SUMMARY OF THE INVENTION
A display mount with post-installation adjustment features according to embodiments of the present disclosure addresses the above-mentioned needs of the industry. The mount may include two or more wall brackets, each having a vertically shiftable carrier assembly. Cross-supports extend between the carrier assemblies and are received in floating connection structures in the carriers. An electronic display display is coupled with the cross-supports. The carrier assembly of each wall bracket is independently vertically shiftable to shift the orientation of the cross-supports, and thereby adjust the vertical position and orientation of the electronic display device coupled with the cross-supports. The electronic display may be coupled to the cross-supports with display interface brackets which are tilt-adjustable to change the tilt position of the display device.
According to an embodiment, a mount for attaching an electronic display to a fixed structure includes a structure interface portion with a pair of horizontally spaced apart wall brackets and a pair of elongate cross supports. Each wall bracket includes a carrier portion, the cross supports vertically spaced apart and extending between the carrier portions of the wall brackets. The carrier portion of each wall bracket is separately vertically positionable to alter the orientation of the cross supports relative to the fixed structure. The mount further includes at least one display interface bracket received on the cross supports. Each carrier portion may include a pair of floating connection structures, each floating connection structure receiving a separate one of the cross supports. The floating connection structures may be spherical bearings.
In embodiments of the invention, the cross supports are separately horizontally shiftable relative to the wall brackets. The at least one display interface bracket may include a tilt mechanism, the tilt mechanism enabling an electronic display device attached to the at least one display interface bracket to be selectively tilted about a generally horizontal tilt axis. The tilt axis may be positioned forward of a display receiving surface of the bracket such that the tilt axis extends through the electronic display device. The structure interface portion may include one or more frame members coupling the wall brackets.
In other embodiments, an electronic display system includes an electronic display device and a mount for attaching the electronic display device to a fixed structure. The mount includes a structure interface assembly and a display interface assembly, the structure interface assembly including a plurality of wall brackets and a plurality of cross supports. The wall brackets are horizontally spaced apart with each of the wall brackets including a guide structure and a carrier. The carrier is selectively vertically shiftable relative to the guide structure with a height adjustment control. The cross supports are vertically spaced apart and extend between the wall brackets. The cross supports are received in the carriers of the wall brackets such that the cross supports are vertically shiftable with the carriers. The display interface assembly includes a pair of display interface brackets spaced apart on the cross supports and the electronic display device received on the display interface brackets.
In embodiments of the invention, each carrier may include a plurality of floating connection structures, each floating connection structure receiving a separate one of the cross supports. These floating connection structures may be spherical bearings. The cross supports may be separately horizontally shiftable relative to the wall brackets.
In embodiments of the invention, each display interface bracket may include a tilt mechanism, the tilt mechanism enabling the electronic display device to be selectively tilted about a generally horizontal tilt axis. Each display interface bracket may present a display receiving surface and the tilt axis may be positioned forward of the display receiving surface such that the tilt axis extends through the electronic display device. The tilt axis can be positioned proximate a bottom edge of the electronic display device.
In other embodiments of the invention, a display system may include a plurality of electronic display devices and a plurality of mounts, each electronic display device mounted on a separate one of the mounts.
In further embodiments, a mount for attaching an electronic display to a fixed structure includes a structure interface with a pair of horizontally spaced apart wall brackets and a pair of elongate cross supports. Each wall bracket includes a carrier slidably shiftable in a guide structure, the carrier including a pair of floating connection structures. The cross supports are vertically spaced apart and extend between the carriers of the wall brackets, each cross support received in a separate one of the floating connection structures of each carrier. The mount further includes at least one display interface bracket received on the cross supports.
In other embodiments, a mount according to the invention may include a shelf assembly operably coupled with one or more of the cross supports, or a speaker attachment operably coupled with one or more of the cross supports.
BRIEF DESCRIPTION OF THE FIGURES
The invention may be more completely understood in consideration of the following detailed description of various embodiments of the invention in connection with the following drawings, in which:
FIG. 1 is a front perspective view of an electronic display and peripheral device mounted on a wall with a mount according to an embodiment of the present invention;
FIG. 1 a is a front perspective view of a mount according to an embodiment of the present invention;
FIG. 2 is a front perspective view of a wall interface of the mount depicted in FIG. 1 a;
FIG. 2 a is a front perspective view of an alternative embodiment of a wall interface of the mount depicted in FIG. 1 a;
FIG. 3 is a perspective view of a first guide member of the wall interface of FIG. 1 a;
FIG. 4 is a perspective view of another guide member of the wall interface of FIG. 1 a;
FIG. 5 is partial cutaway view of the wall interface of FIG. 1 a;
FIG. 6 is fragmentary cross-sectional view taken at section 6 - 6 of FIG. 1 a;
FIG. 7 is perspective view of an end cap portion of the wall interface of FIG. 1 a;
FIG. 8 is a front elevation view of the end cap of FIG. 7 ;
FIG. 9 is a perspective view of a coupling member of the wall interface of FIG. 1 a
FIG. 10 is an exploded view of a spherical bearing assembly of the wall interface of FIG. 1 a;
FIG. 11 is a perspective view of a body plate of the wall interface of FIG. 1 a;
FIG. 12 is a side elevation view of the body plate of FIG. 11 ;
FIG. 13 is a front elevation view of the body plate of FIG. 11 ;
FIG. 14 is a perspective view of a tilt bracket assembly of the mount of FIG. 1 a;
FIG. 15 is a perspective view of a display interface member of the tilt bracket assembly of FIG. 14 ;
FIG. 16 is a perspective view of a hook plate of the tilt bracket assembly of FIG. 14 ;
FIG. 17 is an elevation view of a latch plate of the tilt bracket assembly of FIG. 14 ;
FIG. 18 is a fragmentary perspective view of an upper latch assembly of the tilt bracket assembly of FIG. 14 ;
FIG. 19 is an exploded view of the upper latch assembly of FIG. 18 ;
FIG. 20 is a fragmentary rear elevation view of a portion of the tilt bracket assembly of FIG. 14 ;
FIG. 21 is a side elevation view of the tilt bracket assembly of FIG. 14 ;
FIG. 22 is a fragmentary perspective view of a lower latch assembly of an alternative embodiment of the tilt bracket assembly of FIG. 14 ;
FIG. 23 is a cut-away view of the lower latch assembly of FIG. 22 ;
FIG. 24 is a perspective view of the hook plate of the embodiment of FIG. 22 ;
FIG. 25 is a perspective view of the latch plate of the lower latch assembly of FIG. 22 ;
FIG. 26 is a perspective view of the spring slide of the lower latch assembly of FIG. 22 ;
FIG. 27 is a side elevation view of a mount and display according to an embodiment of the present invention depicting the tilt motion of the mount;
FIG. 28 is a front elevation view of a mount according to an embodiment of the invention;
FIG. 29 is a perspective view of a shelf attachment for the mount of FIG. 1 a;
FIG. 30 is a fragmentary perspective view of the hook assemblies of the shelf attachment of FIG. 29 ;
FIG. 31 is a bottom perspective view of the shelf assembly of FIG. 29 without the shelf;
FIG. 32 is a front perspective view of a mount and accessory attachment according to an embodiment of the invention;
FIG. 33 is a fragmentary view of a portion of the mount of FIG. 32 ;
FIG. 34 is a rear perspective view of the accessory attachment depicted in FIG. 32 ;
FIG. 35 is a front perspective view of the accessory attachment depicted in FIG. 32 ;
FIG. 36 is an end view of the extrusion portion of the accessory attachment of FIG. 35 ;
FIG. 37 is a perspective view of an alternative embodiment of a shelf attachment;
FIG. 38 is a rear perspective view of the shelf attachment of FIG. 37 ;
FIG. 39 is a front perspective view of side speaker attachments with a mount according to an embodiment of the invention;
FIG. 40 is a fragmentary perspective view of a side speaker attachment;
FIG. 41 is a perspective view of an insert portion of the side speaker attachment of FIG. 40 ;
FIG. 42 is an elevation view of a pair of mounts according to embodiments of the invention mounted on a wall, the cross-supports of each mount being shifted to a side of the mount;
FIG. 43 a is an elevation view of a mount according to an embodiment of the invention mounted on the wall of a room wherein the ceiling is not parallel with the floor and the cross supports of the mount have been adjusted to parallel the ceiling;
FIG. 43 b is an elevation view of a mount according to an embodiment of the invention mounted on the wall of a room wherein the mount is slightly skewed and the cross supports of the mount have been adjusted to parallel the ceiling and floor of the room;
FIG. 44 is a front perspective view of an alternative embodiment of a mounting system according to the invention; and
FIG. 45 is a front elevation view of a non-height adjustable embodiment of a mount according to the invention.
While the invention is amenable to various modifications and alternative forms, specifics thereof have been depicted by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives.
DETAILED DESCRIPTION OF THE INVENTION
Mounting system 100 for mounting a flat panel electronic display 102 , and optionally a peripheral device such as a DVD player 104 , on a wall 106 is depicted generally in FIGS. 1 and 1A . Mounting system 100 generally includes wall brackets 108 , 110 , cross-supports 112 , display interface brackets 114 , 116 , and shelf assembly 118 .
As depicted generally in FIGS. 2-13 , wall brackets 108 , 110 , are substantially identical and each generally includes mirror image guide members 120 , 122 , carrier assembly 124 , and end caps 126 , 128 . Each guide member 120 , 122 , includes wall interface flange 130 with guide flange 132 projecting perpendicularly therefrom. Each wall interface flange 130 has an upper 134 and a lower 136 end portion, each defining an elongate rounded notch 138 . When inwardly extending portions 140 , 142 , of guide member 120 are registered and mated with inwardly extending portions 140 , 142 , of guide member 122 , the guide flanges 132 of guide members 120 , 122 , are spaced apart, and the rounded notches 138 of end portions 134 , 136 , define an elongate aperture in each. Each guide flange 132 defines a pair of elongate slots 144 , 146 .
Carrier assembly 124 generally includes mirror image body plates 148 , 150 , a pair of floating connection structures in the form of spherical bearing assemblies 152 , and coupling members 154 , 156 . Each body plate 148 , 150 , defines a pair of cross-support apertures 158 , 160 , surrounded by fastener holes 162 , 164 . Spherical bearing assembly 152 generally includes mirror image housing halves 166 , 168 , and bearing 170 . Each housing half 166 , 168 , defines aperture 172 having an inwardly oriented spherical inner surface 174 conforming to outer surface 176 of bearing 170 . Housing halves 166 , 168 , are mated, with inner surface 178 of housing half 166 confronting inner surface 180 of housing half 168 and apertures 172 registered to define housing 182 . Bearing 170 is captured in apertures 172 with outer surface 176 confronting inner surfaces 174 . Coupling members 154 , 156 , each generally include end flange 184 defining threaded aperture 186 , and projecting legs 188 , 190 . End caps 126 , 128 , each define a horizontally oriented elongate aperture 192 and a vertically oriented aperture 194 .
Coupling members 154 , 156 , are received between ends 196 , 198 , respectively of body plates 148 , 150 . Spherical bearing assemblies 152 are also received between body plates 148 , 150 , the bearing 170 of each registered with one of cross-support apertures 158 , 160 . Fasteners 200 extend through fastener holes 162 , 164 , 202 , 204 , and corresponding fastener holes 206 in housing halves 166 , 168 , and fastener holes 208 in coupling members 154 , 156 , from each side of carrier assembly 124 to secure the assembly together.
Carrier assembly 124 is received between guide flanges 132 of guide members 120 , 122 , as depicted in FIG. 2 . Guide pins 210 , 212 , respectively extend through elongate slots 144 , 146 , and apertures 214 in end caps 126 , 128 . Carrier assembly 124 is thus vertically slidable between guide members 120 , 122 , guided by guide pins 210 , 212 , in slots 144 , 146 .
End caps 126 , 128 , are received on upper and lower end portions 134 , 136 , of guide members 120 , 122 , and are secured in place with fasteners (not depicted) extending through apertures 216 . A height adjustment control in the form of vertical position adjustment screw 218 extends through vertically oriented aperture 194 in end cap 126 and threads into threaded aperture 186 . As vertical position adjustment screw 218 is rotated, carrier assembly 124 slides between guide members 120 , 122 . In an alternative embodiment depicted in FIG. 2 a , guide members 120 , 122 , have end flanges 120 a , 120 b , 122 a , 122 b , respectively, and are connected with end connectors 126 a , 128 a , respectively. Cosmetic caps (not depicted) may be fitted over end connectors 126 a , 128 b , for aesthetic purposes if desired. In another alternative embodiment depicted in FIG. 44 , wall brackets 108 , 110 , are coupled in a single unit with upper and lower frame members 600 , 602 , respectively.
Mirror image display interface brackets 114 , 116 , are generally depicted in FIGS. 14-26 , each generally including display interface member 220 , hook plates 222 , and optionally one or both of upper latch assembly 224 , and lower latch assembly 226 . Display interface member 220 generally includes display interface channel portion 228 with guide flange portion 230 extending perpendicularly thereto. Display interface channel portion defines a plurality of apertures, some of which may be rounded 232 , and some of which may be elongate 234 , for receiving fasteners to attach flat panel electronic display 102 on display receiving surface 236 . Guide flange portion 230 defines guide structures 237 in the form of slots 238 , 240 . Although depicted as slots, it will be appreciated that guide structures 237 may also be configured as other structures fulfilling the same purpose, such as for example, channels, grooves, recesses, ridges, cam surfaces, or the like. Further, it will be appreciated that guide structures 237 may be arcuate, angular, or straight in shape. Guide flange portion 230 further defines friction slot 242 .
Each hook plate 222 defines guide structures 244 , configured as slots 246 , 248 . Upper end 250 defines upper hook 252 , while lower end 254 defines lower hook 256 . Again, although depicted as slots, it will be appreciated that guide structures 244 may also be configured as other structures fulfilling the same purpose, such as for example, channels, grooves, recesses, ridges, cam surfaces, or the like. Further, it will be appreciated that guide structures 244 may be arcuate, angular, or straight in shape. As depicted in FIGS. 14 , 16 , and 21 , upper end 250 may further define latch guide slot 258 and latch adjustment aperture 260 . As depicted in FIGS. 22-26 , lower end 254 may further define latch guides 262 , 264 , and spring pin guide 266 . Friction screw aperture 268 extends through hook plate 222 intermediate slots 246 , 248 .
As depicted in FIGS. 18 and 19 , upper latch assembly 224 generally includes latch plate 270 , guide 272 , guide retainer 274 , and fastener 276 . Latch plate 270 defines geared aperture 278 and guide slot 280 . Shank portion 282 of guide 272 extends through latch guide slots 258 of both hook plates 222 and guide slot 280 of latch plate 270 . Guide 272 is retained with guide retainer 274 and fastener 276 . Geared aperture 278 is registered with latch adjustment aperture 260 of each hook plate 222 . Teeth 282 in geared aperture 278 may be configured to mesh with the tip of a standard Phillips screwdriver.
Lower latch assembly 226 as depicted in FIGS. 22-26 generally includes latch plate 284 , spring 286 , and spring slide 288 . Latch plate 284 defines spring aperture 290 and guide pin apertures 292 . Spring slide 288 is received in spring aperture 290 with notches 294 engaged with opposite sides. One end of spring 286 is received over tab 296 with the opposite end bearing on spring slide 288 . Guide pins 298 are received in each of apertures 292 and are retained in position with retainers 300 . Latch plate 284 is received between lower ends 254 of hook plates 222 , with lateral ends 302 of spring slide 288 projecting through spring pin guides 266 , and the outer ends of guide pins 298 received in latch guides 262 , 264 .
Guide pin 304 extends through slot 238 and the guide slots 246 of both hook plates 222 , while guide pin 306 extends through slot 240 and guide slots 248 of both hook plates 222 . Each guide pin 304 , 306 , is retained on each side with a retainer 308 . Friction screw 310 extends through friction slot 242 and friction screw aperture 268 in each of hook plates 222 and is secured with knob 312 . Friction washers 314 are positioned on each side between guide flange portion 230 and hook plate 222 .
During installation, wall brackets 108 , 110 , are mounted at a desired position on wall 106 with fasteners 316 through elongate apertures 192 in end caps 126 , 128 , as depicted in FIG. 28 , preferably into a load bearing member of wall 106 such as a stud. Wall brackets 108 , 110 , are preferably mounted at substantially the same height H from floor 318 so as to minimize the amount of adjustment needed. It will be appreciated that elongate apertures 192 enable the top and bottom of each of wall brackets 108 , 110 , to be shifted laterally before fasteners 316 are tightened in order to ensure proper vertical alignment.
Once fasteners 316 are tightened, cross-supports 112 may be inserted through the horizontally registered spherical bearings of the wall brackets 108 , 110 . Cross-supports 112 are freely slidable through bearings 170 . If not initially registered, horizontally corresponding bearings 170 of wall brackets 108 , 110 , can be brought into registry by operating vertical position adjustment screws 218 on one or both of wall brackets 108 , 110 , thereby causing carrier assemblies 124 to move vertically. With cross-supports 112 in place, vertical position adjustment screws 218 can also be operated so as to raise or lower the height of cross-supports 112 above floor 318 , to level cross-supports 112 , or to otherwise adjust the orientation of cross-supports 112 relative to other structures in the room such as corners or furniture. In embodiments of the invention, the carrier assembly 124 of each wall bracket 108 , 110 , is independently capable of between ½ to 2 inches of vertical travel. Spherical bearing assemblies 152 enable cross-supports 112 to be oriented out of perpendicular with the carrier assemblies 124 , thereby enabling independent shifting of carrier assemblies 124 without binding.
For example, as depicted in FIG. 43 a , cross-supports 112 may be adjusted to parallel a ceiling 320 that is not parallel with floor 318 . As depicted, the ends of upper cross-support 112 are both the same distance H 1 below ceiling 320 , while the ends of lower cross-support 112 , which is parallel with the upper cross-support, are at differing distances H 3 , H 4 , above floor 318 . When an electronic display 102 is coupled with cross supports 112 , the top and bottom edges of the electronic display 102 will be parallel with ceiling 320 . In another example depicted in FIG. 43 b , mount 100 may be installed such that wall brackets 108 , 110 , are skewed or at differing distances H 5 , H 6 , above floor 318 . Carrier assembly 124 of each wall bracket 108 , 110 , can be independently adjusted so that the ends of cross supports 112 are located a uniform distance from ceiling 320 or floor 318 . When an electronic display 102 is coupled with cross-supports 112 , the top and bottom edges of the electronic display 102 will be parallel with ceiling 320 and floor 318 .
With cross-supports 112 inserted through bearings 170 of wall brackets 108 , 110 , end caps 320 may be inserted in each end of cross-supports 112 to prevent cross-supports 112 from being withdrawn. In embodiments of the invention, cross-supports 112 are laterally slidable within bearings 170 even with end caps 320 in place so as to enable a wider range of lateral positioning relative to wall brackets 108 , 110 . For example, as depicted in FIG. 42 , cross-supports 112 may be shifted to one side or the other, such that mount 100 can be located wherever necessary on wall 106 to ensure fastening to studs or other support structure within wall 106 . As also depicted in FIG. 42 , the ability to laterally shift cross-supports 112 may also facilitate the assemblage of multi display arrays of electronic display devices 102 . Displays 102 can be positioned relative to each other without the necessity of ensuring uniform lateral spacing of mounts 100 .
Display interface brackets 114 , 116 , may be then attached to the back of display 102 with fasteners through apertures 232 , 234 . The plurality of round apertures 232 and the elongate apertures 234 enable brackets 114 , 116 , to be attached at a variety of vertical positions on the back of display 102 .
Display 102 with display interface brackets 114 , 116 , attached may then be coupled with cross-supports 112 by hooking upper hook 252 of each bracket 114 , 116 , over the top cross-support 112 and lower hook 256 of each bracket 114 , 116 over the bottom cross-support 112 . If brackets 114 , 116 , are equipped with upper latch assembly 224 , the latch assembly 224 may be engaged by inserting a Phillips screwdriver through aperture 260 , engaging the tip of the screwdriver with teeth 282 , and rotating the screwdriver. As the screwdriver rotates, guide 272 slides in guide slots 258 and tip 324 of latch plate 270 is urged around cross-support 112 to close the latch. Disengagement is the reverse of engagement
If brackets 114 , 116 , are equipped with lower latch assembly 226 , tip 326 of latch plate 284 encounters bottom cross-support 112 as lower hook 256 is engaged. Latch plate 284 rotates against the bias provided by spring 286 with pins 298 sliding in guides 262 , 264 , and spring slide 288 sliding in guides 266 . Once sufficient clearance exists between tip 326 and upper edge 328 of lower hook 256 to enable passage of cross-support 112 , the bias of spring 286 urges latch plate 284 to snap back into position with lower hook 256 engaged around cross-support 112 . Disengagement is accomplished by pulling outward on the bottom of display 102 with sufficient force to overcome the bias of spring 286 , thereby causing latch plate 284 to rotate in the opposite direction.
With display 102 coupled to cross-supports 112 , the tilt position of the display may then be adjusted as depicted in FIG. 27 . With knob 312 loosened so as to reduce friction, display 102 may be tilted to a desired position by pulling the top of the display away, or pushing the top of the display toward, wall 106 . Guide pin 304 slides or rolls in slot 238 and the guide slots 246 of both hook plates 222 , while guide pin 306 slides or rolls in slot 240 and guide slots 248 of both hook plates 222 to enable tilting. Because of the orientation of slots 238 , 240 , and guide slots 246 , 248 , display 102 pivots about a horizontal pivot axis X-X extending through the display 102 forward a distance Y of the display receiving surface 236 and down a distance Z from a horizontal midline B-B of the display 102 . With this configuration, display 102 is tiltable in either direction with a minimum of effort and tends to remain in position even with knob 312 loose. Once a desired tilt position is reached, however, knobs 312 may be tightened to apply frictional resistance to hold display 102 in the tilt position. Further teachings relating to the optimal orientation of guide slots 238 , 240 , may be found in PCT Application No. PCT/US2008/000117, hereby fully incorporated herein by reference.
Shelf assembly 118 is depicted in FIGS. 29-31 and generally includes hook assemblies 322 , slide 324 , shelf support 326 and shelf 328 . Hook assembly 322 generally includes uprights 330 , hook portion 332 and cross-member 334 . Slide 324 generally includes channels 336 and cross-member 338 . Each of channels 336 defines a plurality of elongate apertures 340 . Shelf support 326 generally includes lateral members 342 and back plane 344 .
As depicted in FIG. 1 a , hook portion 332 hooks over cross-support 112 to suspend shelf assembly 118 from the mount. Uprights 330 are coupled to slide 324 with fasteners extending through elongate apertures 340 . With these fasteners loosened, uprights 330 are slidable relative to slide 324 to adjust height H 1 of cross-member 112 above shelf 328 . Shelf 328 may be made from transparent material such as glass, or from opaque materials, depending on the aesthetic effects desired.
An alternative embodiment of a shelf assembly 346 is depicted in FIGS. 37-38 . Shelf assembly 346 generally includes extrusion 348 , shelf support 350 and hook assembly 352 . Extrusion 348 may be, for example, an aluminum extrusion having a cross-section as depicted in FIG. 36 . Shelf support 350 generally includes a pair of channels 354 connected with a back plane coupler 356 . Shelf support 350 is attached to extrusion 348 with fastener 358 . Hook assembly 352 generally includes coupler 360 and hooks 362 . Hooks 362 may be equipped with a latch assembly similar to previously described upper latch assembly 224 . Hook assembly 352 is attached to extrusion 348 with fasteners 364 . It will be appreciated that hook assembly 352 may be attached at any desired location along extrusion 348 in order to adjust the position of a shelf resting on shelf support 350 relative to cross-supports 112 . In use, hooks 362 are engaged over cross-support 112 in a similar fashion as for the hooks of shelf assembly 118 as previously described.
Accessory attachment 366 as depicted in FIGS. 32-36 may be used to attach various accessories and peripheral devices, such as speaker 368 to mounting system 100 . Accessory attachment 366 generally includes extrusion 370 , hook assembly 372 and device interface 374 . Extrusion 370 may be, for example, an aluminum extrusion having a cross-section as depicted in FIG. 36 . Hook assembly 372 is attached to extrusion 370 with fasteners 376 . It will be appreciated that hook assembly 372 may be attached at any desired location along extrusion 370 in order to adjust the position of device interface 374 and an attached device relative to cross-supports 112 . Device interface 374 generally includes channel 378 and couplers 380 . Couplers 380 are attached to channel 378 with fasteners 382 extending through slot 384 such that couplers 380 are selectively slidable along channel 378 . Each coupler 380 defines an aperture 386 for receiving a fastener (not depicted) to attach a desired device such as speaker 368 . In use, hook assembly 372 is engaged over cross-support 112 as depicted in FIG. 32 to suspend the accessory attachment 366 from mounting system 100 .
In FIG. 45 there is depicted a non-height adjustable version of a mount 604 . Mount 604 generally includes frame 606 having a pair of forwardly projecting flanges 608 , 610 . Cross-supports 112 are received through apertures in each of flanges 608 , 610 , with bearing halves 612 on each side of the flange. Cross-supports 112 are laterally slidable as in the vertically adjustable version depicted in FIG. 42 , thereby enabling a greater range of positioning for mount 604 on wall 106 . It will be appreciated that mount 604 can be used alone in applications where height adjustability is not needed. It will also be appreciated that mount 604 can be used with one or more of mounts 100 to form multi-element arrays where some of the display elements are to be fixed in position and other elements of the array are to be tiltable or height adjustable.
In a further embodiment of the invention, speakers may be laterally attached so as to project on each side of the electronic display using speaker attachments 388 as depicted in FIGS. 39-41 . Each speaker attachment 388 generally includes interface channel 390 , rods 392 and coupler 394 . Small end 396 of coupler 394 is received in the end of cross-support 112 . Coupler 394 defines central bore 398 which slidably receives rod 392 . Each rod 392 is coupled to channel 388 . Channel 388 defines slot 400 for receiving fasteners (not depicted) to attach a speaker to the channel.
It will be appreciated that mount 100 and components thereof can be effectively distributed by packaging one or more of the described mount components in kit form along with user instructions 500 for assembling and attaching mount 100 to a wall 106 , coupling display 102 to mount 100 and adjusting the position of cross-supports 112 and the tilt position of display interface brackets 114 , 116 , in order to position display 102 as desired. User instructions 500 may be provided in printed form as depicted in FIG. 1 a , or in other formats such as video, CD or DVD.
The embodiments above are intended to be illustrative and not limiting. Additional embodiments are encompassed within the scope of the claims. Although the present invention has been described with reference to particular embodiments, those 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. For purposes of interpreting the claims for the present invention, it is expressly intended that the provisions of Section 112, sixth paragraph of 35 U.S.C. are not to be invoked unless the specific terms “means for” or “step for” are recited in a claim. | A display mount with post-installation adjustment features according to embodiments of the present disclosure addresses the above-mentioned needs of the industry. The mount may include two or more wall brackets, each having a vertically shiftable carrier assembly. Cross-supports extend between the carrier assemblies and are received in floating connection structures in the carriers. An electronic display is coupled with the cross-supports. The carrier assembly of each wall bracket is independently vertically shiftable to shift the orientation of the cross-supports, and thereby adjust the vertical position and orientation of the electronic display device coupled with the cross-supports. The electronic display may be coupled to the cross-supports with display interface brackets which are tilt-adjustable to change the tilt position of the display device. | 5 |
RELATED APPLICATIONS
This is a continuation-in-part application of U.S. application Ser. No. 118,667 filed Feb. 5, 1980 which in turn is a continuation-in-part application of U.S. application Ser. No. 70,839, filed Aug. 29, 1979, now U.S. Pat. No. 4,238,173, issued Dec. 9, 1980, which is in turn a divisional application of U.S. application Ser. No. 654,416, filed Feb. 2, 1976 now U.S. Pat. No. 4,216,178 issued Aug. 5, 1980.
BACKGROUND OF THE INVENTION
The fabrication of gas discharge lamps requires that precise quantities of high purity mercury and alkali metals (e.g., sodium) be introduced into the gas envelope of the lamp. Of particular interest in recent years are high pressure sodium lamps which require vaporizable fills of sodium and mercury. These lamps have assumed commercial importance because of their high efficiency, typically in the range of 100 to 120 lumens per watt. The light output of high pressure sodium lamps is characterized by strong continuum radiation and a line spectrum richer than that associated with conventional mercury vapor lamps. High pressure sodium vapor lamps have been found particularly useful and effective in anti-crime lighting systems deployed in many urban areas.
A high pressure sodium vapor discharge may be created within a discharge tube formed from a high temperature, alkali-vapor resisting transculent polycrystalline alumina envelope with generally oppositely disposed electrodes. The operating pressure may range from 100 to 200 torr. Sodium, among the alkali metals, provides a high pressure discharge of the highest luminous efficiency and has relatively good spectral distribution. Mercury may be added to the sodium in the discharge tube as a buffer gas. Commonly a noble gas at approximately 15 torr pressure is placed in the tube as a starting gas.
In the preparation of these lamps, molten sodium-mercury amalgam has been dispensed into the gas envelope of the lamp by means of a vacuum needle pick-up. This technique is ineffective and poorly adapted to use on high volume manufacturing lines for several reasons. First, the ambient surroundings, materials, and equipment associated with the dispensing operation must be maintained at elevated temperatures, typically from 66° to 220° C., in order that the amalgam may remain in a molten state. Also, since the molten amalgam is extremely susceptible to oxide formation and since sodium will react with water, the dispensing operation must be performed in a controlled, inert water-free atmosphere. Finally, dosing needles employed to dispense the molten amalgam are continually clogged by sodium oxide floats or by decomposition of the needle itself from reaction with the corrosive alloyed sodium. The dosing of improper quantities of mercury and vaporizable sodium is a principal cause of high lamp rejection rates (often about 50 percent or more) associated with this process. There is also a health hazard associated with the use of a hot amalgam is the system should break and get toxic mercury in the atmosphere. In addition, hot sodium can explode if there is sufficient moisture in the atmosphere.
Another disadvantageous dosing procedure practiced by other lamp assemblers entails dispensing a carefully measured quantity of liquid mercury into a gas envelope of a lamp, inserting an open ended tantalum tube containing a measured quantity of solid sodium metal into the gas envelope, sealing the gas envelope, and heating the tantalum tube with a high frequency generator to vaporize the sodium. The procedure has several obvious disadvantages. First the liquid mercury may be partially retained in dosing conduits, thereby varying the composition of the fill. Sodium, exposed on the ends of the tantalum tube, may oxidize, thereby also varying the composition of the fill. Any sodium which is oxidized does not form an amalgam with the mercury. The procedure is a time consuming, multi-stage operation requiring the performance of two measuring and two dispensing steps, the sealing of the gas envelope, and the application of high frequency energy to vaporize the sodium. Finally, the lamp fabricated by this procedure will contain an extraneous piece of tantalum tubing within its gas envelope.
A need remains in the art for a fast, relatively simple and accurate procedure of dosing sodium amalgams into gas lamp envelopes.
An advantageous process and apparatus for the manufacture of discrete particles of metal halide particles is disclosed in U.S. Pat. No. 3,676,534.
OBJECTS AND SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a method for making a sodium amalgam of controllable composition and negligible impurity content in a form adapted for convenient dosing of electric discharge lamps in an assembly line environment.
Another object of the present invention is to provide a method for providing sodium amalgam particles easily and accurately measurable into variable volumes or counted so as to be suitable for rapid dosing of lamps by lamp making machinery and a method for dosing of lamps utilizing these particles.
Another object of the present invention is to provide a method for forming free-flowing sodium amalgam particles of controllable particle size and a method of using the product to dose a lamp with a predetermined amalgam composition.
In accordance with one aspect of the present invention, there are provided a method of providing free flowing, discrete sodium amalgam particles composed of from about 2 to about 30 weight percent sodium and from about 98 to about 70 weight percent mercury, said particles containing less than 10 ppm of sodium oxides. Preferably, the amalgam is composed of from about 10 to about 26 weight percent sodium and concomitantly from about 90 to about 74 weight percent mercury. The sodium oxide content of vaporizable fill used in lamp fabrication is of particular importance because sodium oxide tends to form a compound deleterious to lamp performance when it comes in contact with conventional lamp gas envelopes.
In another aspect of the present invention, there is provided a method for filling a gas discharge lamp with an accurately controllable quantity of high purity sodium amalgam, comprising: portioning out a volume of free-flowing sodium amalgam particles corresponding to a desired quantity of sodium amalgam; and introducing said volume of amalgam particles into a gas envelope of a gas discharge lamp.
In accordance with another aspect of the present invention, there is provided a method for producing free-flowing, discrete sodium amalgam particles of controlled particle size and low sodium oxide content comprising: heating a mixture of sodium and mercury in a vessel to form an amalgam melt of determinable unoxidized sodium content, withdrawing a portion of said melt from the vessel at a point other than at an upper surface of said melt; and passing the withdrawn portion of said melt through a vibrating discharge conduit into an inert, quenching atmosphere to form particles of said amalgam. The inert quenching atmosphere may be dry gaseous helium where the gaseous helium is maintained at a temperature of less than minus 150° C., by indirect heat exchange with liquid nitrogen or may be substantially water-free liquid nitrogen.
In accordance with another aspect of the present invention, a novel method is provided using apparatus particularly adapted for the production of said sodium amalgam particles. The apparatus may comprise a heated vessel for containing the amalgam melt, means for forming said amalgam into droplets comprising a vibrating conduit through which the molten amalgam may exit the vessel by a pressure gradient established by an inert pressurized fluid in the apparatus, and a column of inert cooling fluid for receiving the droplets. The inert cooling fluid is maintained at a temperature sufficient to solidify the droplets. The column of inert cooling fluid may comprise a column of substantially water-free liquid nitrogen or a column of inert cooling fluid being substantially surrounded by and in indirect heat exchange relationship with a liquid bath (such as liquid nitrogen) to maintain the inert cooling fluid at the desired temperature. In a preferred embodiment, the vibrating conduit is a bore in a lower wall of the heated vessel, which bore is vibrated by an electro-mechanical transducer and which has an exit end including a concave indentation having a hole through which the amalgam exits the lower wall of the heated vessel. The bore may also contain sumps disposed below the hole in the concave indentation to trap relatively heavy impurities.
In accordance with another aspect of the present invention, a novel method is provided using apparatus particularly adapted for the production of said sodium amalgam particles having a diameter in the range of 500 to 1400 microns, preferably in the range of about 800 to 1300 microns. In a preferred embodiment, a funnel is suspended below the first funnel and filled to a predetermined level so that the velocity of the melt at the discharge nozzle may be controlled, i.e., low but sufficient to provide a continuous stream.
These and other aspects and advantages of the present invention will be readily apparent to one skilled in the art to which the invention pertains from the claims and the following more detailed description of a preferred embodiment when read in conjunction with the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of an apparatus which may be employed to produce substantially pure, free-flowing, alkali metal amalgam particles in accordance with the present invention;
FIG. 2 is a schematic representation of an alternate embodiment of an apparatus which may be employed to produce substantially pure, free-flowing, alkali metal amalgam particles in accordance with the present invention;
FIG. 3 is a cross-sectional elevation of a nozzle structure employed to produce droplets of substantially pure alkali metal amalgam melt in accordance with the present invention; and
FIG. 4 is a cross-sectional elevation of a nozzle structure particularly adapted for relatively large diameter pellets; and
FIG. 5 is a cross-sectional elevation of a second embodiment of a nozzle structure particularly adapted for pellets of relatively large mass.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, a purification vessel, denoted generally by the numeral 10, and generally formed of an inert material such as silica, nickel or stainless steel, has an upper vessel section 12 for holding the amalgam 20 and means 25 for vibrating the lower end thereof. The upper vessel section 12 has a removable upper vessel section cap 14 which may be removed to permit mercury and sodium or a preformed sodium amalgam to be introduced into the upper vessel section. The upper vessel section cap 14 is provided with an outlet 16 for the egress of various gases therefrom. The upper vessel section 12 is substantially surrounded by a conventional furnace 18 to heat and maintain the melt above the melting point of the amalgam.
The upper vessel section 12 terminates in a nozzle 26 formed with an aperture 28 through which molten amalgam may exit the upper vessel section. A silica or stainless steel filter 24 may be disposed above the nozzle 26. The vibrating means 25 may consist of an electromagnetic transducer 30 mechanically connected to nozzle structure 26 by a quartz rod 32 whereby vibrations are transmitted to the molten amalgam as it passes through aperture 28, separating the molten amalgam into discrete droplets 33 of controlled particle size. The size and positioning of the discrete droplets are observed by optical means 34 under the illumination of stroboscopic light source 36.
The upper vessel section 12 is hermetically sealed in axial relationship with a lower vessel section 38 which comprises a cooling gas inlet 40, a condensation chamber 42 and a collection chamber 50. The droplets 33 of molten amalgam fall freely through condensation chamber 42 containing an inert cooling fluid to solidify the droplets into solid amalgam particles of regular size and shape. A cooling fluid may provide an updraft through which the particles fall. The cooling fluid, which may be introduced into lower vessel section 38 through gas inlet 40, may be maintained at a temperature well below the melting point of the amalgam by indirect heat exchange with a coolant jacket 44, typically containing liquid nitrogen, which coolant jacket 44 may be surrounded by an evacuated insulation jacket 46. A vacuum is induced in the insulation jacket 46 by application of suction through vacuum draw tube 48.
In a preferred embodiment of the present invention, solidified particles of amalgam exit lower vessel section 38 through funnel 49 and enter a cooled collection receptacle 50. The collection receptacle 50 is maintained at a temperature well below the melting point of the amalgam by a coolant 52, typically liquid nitrogen, and surrounded by a second evacuated, thermal insulation jacket 54.
In operation, the upper vessel section 12 may be heated to a temperature above the melting point of the sodium amalgam. A vacuum may be applied through outlet 16 by conventional suction means (not shown) while the upper vessel section is being heated. When the upper vessel section 12 is heated to the desired temperature, an inert gas (such as argon) is passed through gas inlet 40 and withdrawn through oulet 16 at a pressure sufficient to maintain the amalgam in the upper vessel section 12. While the argon is thus flowing through the aperture 28 and upper vessel section 12, the cap 14 may be removed and solid sodium inserted into the upper vessel section 12. The sodium melts inside the upper vessel section 12 and the flowing argon gas pressure maintains the molten sodium in the upper vessel section 12. Mercury is added incrementally to the molten sodium because of the large amount of heat evolved when mercury is added to sodium. After the desired amount of mercury is added, argon flow may be continued until the amalgam melt is cooled to the desired temperature. The sodium amalgam may also be added to the upper vessel section 12 as a pre-formed amalgam. When so added, the pre-formed amalgam is heated in the upper vessel section 12 under inert gas flow and formed into discrete particles in the same manner as an amalgam formed in the upper vessel section 12.
Thereupon, an inert cooling fluid such as helium is placed in the lower vessel section 38 and in the upper vessel section 12 so that the molten amalgam is forced downwardly through the nozzle 26 and separated by vibration as it passes through the aperture 28 into the discrete droplets 33 of controlled particle size.
The inert cooling fluid in the lower vessel section 38 is maintained at a temperature well below the melting point of the sodium amalgam and sufficient to solidify the particles. The present invention is particularly suited to the production of sodium amalgams containing from about 2 to about 30, preferably from about 10 to about 26, weight percent sodium and, concomitantly, from about 98 to about 70, preferably from about 90 to about 74, weight percent mercury. Relatively pure sodium and mercury or sodium amalgam should be utilized in order to maintain the purity of the final product particles as high as possible. Preferably, the sodium is relatively potassium free (i.e., contains less than 100 ppm potassium) and the mercury is triple distilled. These amalgams have melting points in the range of from about 50 to about 353, preferably from about 60° to about 220° C. The inert cooling fluid in the lower vessel section is generally maintained at a temperature below minus 150° C., preferably below about minus 180° C. The boiling temperature of the liquid nitrogen in coolant jacket 44 is minus 196° C.
Referring to FIG. 2, a purification vessel of an alternate embodiment of the present invention is denoted generally by the numeral 70. The embodiment utilizes an upper vessel section 71, nozzle 72, conventional furnace 73, and electromechanical transducer 74 in substantially the same configuration as the equivalent elements of the embodiment depicted in FIG. 1. In the alternate embodiment of FIG. 2, molten amalgam 75 may pass through nozzle 72 and is formed into droplets 76 of generally uniform size. The droplets may then pass into a chamber 77 containing an inert gas (e.g., helium) which exits the purification vessel via inert gas input conduit 78 and which enters the purification vessel through inert gas conduit 80. Said inert gas may also exit the purification vessel by passing through upper vessel section 71 and exiting via gas outlet 82. By controlling the exiting of the gas, the pressure in the condenser and thus the rate of flow from the funnel 72 may be controlled. The lower vessel section 83 may be provided with a collection receptacle 90 for receiving solidified amalgam particles. The apparatus of FIG. 2 is otherwise constructed similar to and may be utilized in the same manner as the apparatus of FIG. 1.
Referring to FIG. 3, a nozzle structure which may be advantageously employed to form regular sized droplets of molten amalgam is denoted generally by the numeral 100. Vibrating means 101 causes nozzle 102 to transmit vibrations to molten amalgam 110 and thereby cause the molten amalgam to separate into discrete droplets 114 to regular size. Surface tension draws the molten amalgam droplet into substantially spherical form.
The frequency of the vibrations and the velocity of the stream 112 of molten amalgam issuing from nozzle 102 causes predictable separation of the continuous stream into individual droplets 114.
The theory of producing orderly drop formation from a liquid jet by use of a controlled vibration was discussed in detail by Lord Rayleigh in 1877 in Theory of Sound, 2nd Edition, Vol. II; Chapter 20, New York, Dover Publications. Rayleigh showed that the optimum droplet size uniformity is achieved when the wavelength, λ, of the imposed vibrations is equal to approximately 4.5 times jet diameter, φ j .
λ=4.5 φ.sub.j (1)
Assuming a design choice of uniform droplets with a radius R, the volume of each such droplet is given by the expression
(4/3)πR.sup.3. (2)
The contraction of an amalgam droplet on solidification is slight and can be neglected, so that the volume of solid particle is approximately equal to the volume of the droplet.
The volume of the formed droplet is equal to the volume of liquid contained in one wavelength, λ, of the molten amalgam stream 112 before it breaks into droplets. To a first approximation, this volume is given by the expression ##EQU1## where r j is the radius of the amalgam stream as it leaves the nozzle. Neglecting the contraction coefficient of the melt, r j will equal the radius of the aperture. Since the volume of the droplet is equal to the expression (3): ##EQU2## Thus, for example, to produce a solid particle with a radius R, a nozzle aperture with a radius of a magnitude of approximately R/2 should be chosen.
When forming droplets the frequency, f, of the vibrating transducer and velocity of the amalgam stream, V, should be maintained at values which will establish a wavelength approximately equal to 4.5 φ j . This can be done because ##EQU3## where Δp=the pressure differential in the direction of a principle axis of the aperture in the nozzle and g=the acceleration due to the force of gravity. Optimum results and best droplet size control are achieved where the frequency of vibration is given by the expression ##EQU4## The droplet size can be varied somewhat by changing Δp and f. However, for a reasonable yield of uniform particles, the wavelength should be limited according to the expression
3.6 φ.sub.j ≦λ≦6.2 φ.sub.j (8)
Droplet uniformity, size control, and purity may be improved by employing the nozzle structure depicted in FIG. 3. In that embodiment, upper vessel section wall 104 may have an inwardly concave indentation 106 in a lower portion of said vessel wall.
An upper portion of the concave indentation 106 may be formed with at least one bore 108 with an entrance end 109. The upper vessel section may be formed with a concentric sump 110 lower than the entrance end 109 of the bore 108 and which may serve to trap relatively heavy impurities which may sink to the bottom of the melt.
The filter 24 (FIG. 1) or 79 (FIG. 2) disposed in the upper vessel section above the nozzle 26 (FIG. 1) or 72 (FIG. 2) serves to remove any solid impurities, e.g., sodium oxide, tramp iron, carbon or the like, within the melt. Any such solid impurities which pass through the filter and come into contact with the inner walls of the concave indentation 106, and which have a specific gravity greater than that of and amalgam, will tend to sink by gravity and remain in the sump 110. In this manner, the purity of the particles formed will be enhanced. The sodium amalgam particles of the present invention generally contain less than about 10 ppm of sodium oxide impurity.
The process of the present invention is advantageously utilized to form discrete, free-flowing sodium amalgam particles of generally spherical form and having a diameter of from about 240 to about 480, preferably from about 315 to 385, microns. It has also been found that the particles produced are generally uniform in size for a given set of conditions. That is, essentially all of the particles (e.g., 90% or more) produced with a particular nozzle structure, vibration frequency, composition, temperature and the like, will be within about ±10% of the theoretical particle diameter.
The particles of the present invention offer substantial advantages in the production of sodium amalgam gas discharge lamps. For example, the amalgam composition used to dose the lamps is uniform. Dosing with the relatively small, uniformly sized particles of the present invention can easily be performed by machines at ambient temperature and can also be pre-calculated on a volume basis due to the uniformity of composition and size.
The making of larger size particles, i.e., from about 2 to 6 mgs./particle, is advantageous in that dosing may be accomplished by counting particles and in that the surface area per gram is reduced thereby reducing the likelihood of contamination.
The invention is additionally illustrated in connection with the following Examples which are to be considered as illustrative of the present invention. It should be understood, however, that the invention is not limited to the specific details of the Examples.
EXAMPLE 1
High purity, free-flowing sodium amalgam particles containing 17 weight percent sodium and 83 weight percent mercury and of generally uniform size are prepared employing the apparatus of FIG. 1 in the manner hereinafter set forth.
Upper vessel section 12 is heated to 125°-130° C. while being evacuated. This temperature is slightly above the melting point (about 118° C.) of the 17 weight percent sodium amalgam. The vessel is then filled with purified argon gas, which argon gas flows into the vessel via input tube 40 and flows up through nozzle 26 to fill upper vessel section 12. While the argon gas is flowing, upper vessel section cap 14 is removed and a precisely weighed quantity of high purity solid sodium (containing less than 100 ppm. potassium) is placed on filter 24. The sodium melts inside the upper vessel section. The flowing argon keeps the melt on top of the filter. With argon flowing through the upper vessel section, triple-distilled mercury is incrementally introduced into the upper vessel section a small amount, e.g., 1/2 to 1 cc., at a time until a sufficient quantity (83 weight percent of the resulting amalgam) has been added. The mercury is added slowly because a great amount of heat is evolved in the amalgam formation.
After adding mercury, helium is passed up through the molten amalgam for 1/2 hour to cool the amalgam to 125° C. Thereafter, 7.9 psi of helium is placed in the upper vessel section 12 above the amalgam while 2.2 psi of helium is maintained within the coolant column 38. The pressure differential Δp, thereby created, forces the molten amalgam through the filter 24 and the nozzle which is vibrated at a frequency of 7.2 KHz using a conventional quartz rod 32 and a radio speaker 30 (not shown), with a conventional variable oscillator and amplifier being used to drive the speaker. The molten sodium amalgam comes out of the nozzle in a continuous stream which then breaks up into individual droplets. The droplets solidify during their fall in the condensation chamber 42 containing high purity helium gas essentially at the temperature of the boiling liquid nitrogen (minus 196° C.) which surrounds the condensation chamber and is in indirect heat exchange with the inert helium cooling gas.
After the droplets have solidified by passing through coolant column 38, they are received in cooled collection receptacle 50. The product particles contain less than 10 p.p.m. of sodium oxide and have a particle size of from about 160 to 320μ with 95% of the amalgam particles having a diameter being 220 and 275μ.
A quantity of the sodium amalgam particles produced is introduced into a conventional aluminum oxide gas discharge lamp housing. The lamp is sealed (with a noble gas at about 15 torr pressure) and in operation shows excellent and uniform spectral properties and uniform starting potentials.
EXAMPLE II
High purity, high sodium content amalgam particles of generally uniform size are prepared employing the apparatus of FIG. 2. Using the procedure of Example I, a sodium amalgam containing 25 weight percent sodium, 75 weight percent mercury (melting point about 66° C.) is formed in the upper vessel section 71. Particles are formed in the manner of Example I.
The resulting particles have a size of from about 250 to about 425μ with 95% of the particles having a diameter between about 315 and 385μ. The particles have a sodium oxide content of less than 10 p.p.m. and are used to dose a conventional sodium amalgam discharge lamp in the same manner as the particles of Example I. The resulting lamp exhibits excellent spectral properties and uniform starting potentials.
Where particles of larger size are desired, the initial velocity of the melt at the orifice of the vibrating nozzle becomes a problem in that the length of the condenser necessary to quench the amalgam particles in helium at the temperature of liquid nitrogen becomes excessive. In addition, there is the tendency of solidified particles to fragment on impact due to the terminal velocity, and the tendency of insufficiently solidified particles to deform on impact. Since the shape of the particles may be critical in a dosing operation requiring that the particles be free-flowing, it is desirable to reduce the initial velocity of the particles.
With reference to the embodiment of FIG. 4, the diaphragm 120 at the bottom of the funnel or vessel 122 is provided with four or five apertures of approximately 200 microns in diameter so that the amalgam can be forced rather quickly through the frit 124 into the jet funnel 126 to a height sufficient to immerse the diaphragm 120. Under these conditions, the initial velocity at the orifice 128 of the jet funnel 126 is a function of the hydrostatic head of the amalgam in the jet funnel 126 as contrasted with the amalgam above the frit 124 in the vessel 122.
The depth of the amalgam in the jet nozzle 126 may be maintained by the pressure applied above the amalgam within the vessel 122. Thus the pressure can be adjusted to quickly fill the jet funnel 126 to the desired depth and to thereafter maintain the desired depth. The velocity of the melt as it exits the orifice 128 may thus be maintained independently of the pressure differential between the vessel 122 and the condenser vessel. The diameter of the orifice may be adjusted to change the diameter of the particle produced and is larger than the aperture in the funnel 122.
An example follows. It should be understood, however, that the invention is not limited to the specific details.
EXAMPLE III
High purity, free-flowing sodium amalgam particles containing 19 weight percent sodium and 81 weight percent mercury of generally uniform size may be prepared using the procedure of Example I to form the amalgam in the upper vessel section in the apparatus of FIG. 4 and to force the amalgam through the frit 124 to fill the jet funnel 126 to a height sufficient to immerse the diaphragm 120. The diaphragm 120 is provided with 4 or 5 holes of 200 microns in diameter. Under these conditions, the jet velocity at the orifice 128 is the sole function of the hydrostatic head of the amalgam in the jet funnel 126, and is virtually equal to that of a freely falling body falling through the height S. The velocity is thus given by the formula: ##EQU5## where V is the velocity, g is the acceleration of gravity, S is the depth of the amalgam, and C≦1.0 and may be a function of the composition of the amalgam, its viscosity and/or surface tension, and possibly the diameter of the nozzle.
Once the desired depth S is reached, the depth is maintained by the rate at which the amalgam is forced through the frit 124 and is independent of the pressure differential between the condenser and main vessel.
With S=82 millimeters, an orifice diameter of 395 microns and a frequency of 150 Hertz, a 75-80% yield of particles of 1050 microns in diameter and 2.9 milligrams in mass were produced.
The length of the condenser is desirably about 2 meters with the tip thereof within 4 to 5 inches of the melting furnace. Since: ##EQU6## where t is time, each particle spends most of its falling time in the upper end of the condenser.
EXAMPLE IV
High purity, free-flowing sodium amalgam particles containing 25 weight percent sodium and 75 weight percent mercury of generally uniform size may be prepared using the procedure of Example I to form the amalgam in the upper vessel section in the apparatus of FIG. 4 and to force the amalgam through the frit 124 to fill the jet funnel 126 to a height sufficient to immerse the diaphragm 120. The diaphragm 120 is provided with 5 holes of 250 microns in diameter.
Once the desired depth S is reached, the depth is maintained by the rate at which the amalgam is forced through the frit 124 and is independent of the pressure differential between the condenser and main vessel.
With S=117 millimeters, an orifice diameter of 507 microns and a frequency of 155 Hertz, a 85% yield of particles of 1350 microns in diameter and 5.5 milligrams in mass were produced.
With reference to FIG. 5, the jet funnel 126 of FIG. 4 may be replaced by a jet funnel 130 having a single aperture 132. It is, however, important that the jet funnel 130 does not have a fluid tight seal to the column 133.
To eliminate problems arising from insoluble particles which either pass through the frit 124 of FIG. 4, or result from the physical deterioration of the frit, each of the holes in the diaphragm 120 of FIG. 4 may be smaller in diameter than the single hole in the jet funnel 130 so that any particle passing through the diaphragm 120 will pass through the nozzle aperture 132.
It is desirable that the combined area of the holes in the diaphragm 120 of FIG. 4 be equal to or greater than the area of the hole 132 in the jet nozzle 130. However, the adjustment of the pressure above the frit 124 can be made to adjust the rate of inflow through the diaphragm 120 vis-a-vis the outflow of the jet nozzle 130.
When particles of larger mass, e.g., 3.3 mg to 6.0 mg, are required as contrasted with particles of about 325 microns in diameter (about 0.1 mg) for which FIG. 4 is well suited, a 1 kg. run will be reduced from between about one and one-half and two hours to between about eighteen to twenty minutes. Because of the large mass of such particles, it is desirable to reduce the temperature in the collector as well as the temperatures in the cooling column to that of liquid nitrogen.
Using the embodiment of FIG. 5, the velocity of the melt exiting the jet funnel 130 is a function of the depth of the melt in the funnel and is entirely independent of the pressure differential between the pressure above the frit and in the collector. The depth of the melt in the funnel 130, and thus the hydrostatic head, may be easily maintained where the combined area of the holes in the diaphragm 120 is about twice that of the area of the hole in the jet funnel 130.
An illustrative example follows:
EXAMPLE V
High purity, free-flowing sodium amalgam particles containing 20 weight percent sodium and 80 weight percent mercury of generally uniform size may be prepared using the procedure of Example I to form the amalgam in the upper vessel section in the apparatus of FIG. 4 and to force the amalgam through the frit 124 to fill the jet funnel 126 to a height sufficient to immerse the diaphragm 120. The diaphragm 120 is provided with 5 holes of 250 microns in diameter.
Once the desired depth S is reached, the depth is maintained by the rate at which the amalgam is forced through the frit 124 and is independent of the pressure differential between the condenser and main vessel.
With S=9.5 centimeters, an orifice diameter of 0.0483 centimeters and a frequency of 150 Hertz, a 66% yield of particles of 1350 microns a diameter and 5.4 milligrams in mass were produced.
The principles, preferred embodiments and modes of operation of the present invention have been described in the foregoing specification. The invention which is intended to be protected herein, however, is not to be construed as limited to the particular forms disclosed, since these are to be regarded as illustrative rather than restrictive. Variations and changes may be made by those skilled in the art without departing from the spirit of the invention. | Substantially pure, free flowing, sodium amalgam particles of predetermined composition and controlled particle size are prepared for use as vaporizable fill for high pressure discharge lamp devices, whereby accurately measurable quantities of the sodium amalgam may be introduced into the lamp devices. A process for producing the substantially pure amalgam particles of accurately controlled size includes heating a mixture of sodium and mercury to form a melt, passing the melt through a vibrating discharge nozzle and subjecting the droplets so formed to an inert cooling fluid maintained at a temperature below the solidification point of the amalgam. An apparatus for producing the amalgam particles comprises a vessel to contain an alkali metal amalgam melt, a virbrating discharge nozzle adatped to form the melt into uniformly sized droplets, and a column of inert cooling fluid maintained at a low temperature at which the melt droplets are solidified. Where spheres in the range of 500-1400 microns are desired, the velocity of the melt exiting the nozzle may be reduced to approximately zero and an updraft in the coding fluid provided to assist quenching. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to mechanical power transmission systems and more particularly, it concerns a torque transmission system and method by which the torque path between system input and system output is split between at least two infinitely variable transmission units in a manner to optimize the efficiency of each such unit over a wide range of system torque loads and speeds ratios.
Mechanical power transmissions which transmit torque from an input to an output at infinitely variable speed ratios are well known in the art and generally referred to as "I.V. transmissions". Because the power generating efficiency of most engines or prime movers is highest in only a limited range of operating speeds, I.V. transmissions have and continue to generate much interest as a potentially ideal solution to the transmission of power from a power source to a power consuming load which must be driven at speeds varying from the operating speeds of the power source.
Mechanical I.V. transmissions are generally embodied in a structural organization capable of transmitting torque by friction between two or more traction surfaces on relatively rotatable bodies supported in such a manner as to enable the traction surfaces to be retained against one another under a normal force adequate to prevent slippage between the surfaces. The infinitely variable speed ratio is achieved by designing the torque arm or radius of one of the bodies to be continuously variable relative to the radius of the other body. The geometric configuration of two such bodies capable of attaining this result is exemplified by a wheel shiftable axially on a disc or a ring shiftable along the axis of a cone.
In a commonly assigned co-pending U.S. application Ser. No. 706,291, filed July 19, 1976, by Yves Jean Kemper, now U.S. Pat. No. 4,152,946 issued May 8, 1979, the present inventor, several embodiments of an I.V. transmission are disclosed in which torque is transmitted between a first body, represented by a pair of axially movable internal traction surfaces of revolution about a first axis, and a second body represented by a pair of external cone-like traction surfaces of revolution about a second axis inclined with respect to and intersecting the first axis at a point of axes intersection. The second body is supported rotatably on its own or second axis in a crank-like supporting body journalled for rotation about the first axis. Torque applied to the crank-like body results in nutational movement of the second axis about the first axis and rotation either of the second body about the second axis or of the first body about the first axis. In embodiments where the first body is held against rotation as a reaction member, the second body rotates about the second axis as a result of its frictional engagement with the traction surfaces on the first body at two points of engagement spaced equally and oppositely along the first axis from the point of axes intersection. A pinion gear coupled at one end of the second body orbits in planetary fashion about the first axis while in mesh with an orbiting idler engaged with a sun gear carried on an output shaft. The planet gear output in such a transmission offers flexibility in the transmission design by which a unidirectional constant velocity input may be transmitted as an output varying from zero to the approximate speed of the input in one direction; varying from zero to input velocity but in the opposite direction; or varying continuously from an intermediate output speed in the same direction as the input through zero to a directional reversal of the input.
While the state of the art relating to I.V. transmissions has been developed to a point of practical application in transmitting power of magnitude corresponding to that required by automotive vehicles and higher, the efficiency curve for an I.V. transmission, whether it be of the type disclosed in the afore-mentioned copending application or any of several other types, is the approximate reciprocal of the torque function of the power transmitted. At constant input power, therefore, transmission efficiency is highest with increased output speeds and lowest at low output speeds where torque multiplication is greatest. The need for improvement in an I.V. transmission system by which operating efficiencies can be improved while at the same time retaining the speed varying capabilities thereof will thus be appreciated by those skilled in the art.
SUMMARY OF THE INVENTION
In accordance with the present invention, a transmission system input is split between two or more independently adjustable I.V. transmission units and combined in a system output through a controlled epicyclic gear train operated in such a manner that I.V. unit efficiency is optimized in the transmission of system power over a wide range of system speed ratios. The I.V. units are preferably of a type in which unit output speed is a function of both traction surface radius ratio and unit gear ratio to maximize the range of system operation. In one embodiment, for example, both of the I.V. units may be provided with the same unit gear ratio and the unit outputs connected respectively to the sun and ring gears of a planetary gear train in which the planet carrier is connected to system output. In such an arrangement, three modes of system operation are effected. In one mode, the unit coupled to the ring gear of the planetary train is held against rotation so that the other unit will drive system output variably through the gear reduction afforded by the planetary unit. In a second range, both I.V. units are operative and independently adjusted to assure an equal division of transmitted power between the two units. In a third mode of operation, one of the two units is operated without adjustment at its highest output/input speed ratio whereas the other is adjusted to provide the variation in system output. As a result of this operation, system power is transmitted at low speeds and relatively high torque by one I.V. unit operating at high efficiency while system power transmitted over the major range of speeds and torques is split equally between the I.V. units.
Alternately, one of the two I.V. units is provided with a unit gear ratio by which the output of that unit may be varied in relation to system input both as to speed and direction. The other of the two units is designed with a gear ratio to maximize the range of speed ratios available at the other unit output for a given system input speed. By using as the epicyclic gear train, a differential in which rotation of a planet carrier is effected by rotation of two bevel gears of the same size, connecting the unit outputs to the bevel gears and system output to the planet carrier, unit operation may be alternated and combined to provide a system output having a wide range of speed ratios relative to system input including a directional reversal of system input. Moreover, the differential gearing unit may be used to provide a gear reduction factor of two merely by braking one of the two bevel gears coupled to the output of one of the I.V. units and transmitting system power through only the other of the units at increased unit efficiency. When both I.V. units are driving system output in the same direction, the variable ratio of each unit is adjusted to split equally the power transmitted by each unit as in the first-mentioned embodiment.
Among the objects of the present invention are, therefore: the provision of an improved infinitely variable transmission system in which system input is transmitted to system output by way of at least two infinitely variable transmission units; the provision of such a system in which rated power of each I.V. unit is a fraction of rated power of the system, the fraction approximating the reciprocal of the number of units used in the system; the provision of such a system which may be conveniently packaged; the provision of such a system in which the work performed by the respective infinitely variable units is equally divided; the provision of such a system in which the range of system speed ratio variation is increased over the range of speed ratio variation available in the units individually; and the provision of such a system in which the efficiency of the respective infinitely variable units is optimized.
Other objects and further scope of applicability of the present invention will become apparent from the detailed description to follow taken in conjunction with the accompanying drawings in which like parts are designated by like reference numerals.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partially schematic perspective view illustrating the exterior structure of the transmission system of the present invention;
FIG. 2 is an enlarged fragmentary cross-section on line 2--2 of FIG. 1;
FIG. 3 is a schematic cross-section on line 3--3 of FIG. 2.
FIG. 3A is a view similar to FIG. 3 but showing a different gearing arrangement;
FIG. 4 is a graph with linear curves representing various unit gearing reduction factors in relation to transmission ratio changes and output speed;
FIG. 5 is a schematic view representing one embodiment of the system of the invention;
FIG. 6 is a diagram including efficiency curves for the transmission units of the embodiment illustrated in FIG. 5;
FIGS. 7-9 are schematic views depicting three modes of operation of an alternative embodiment of the present invention; and
FIG. 10 is a graph illustrating transmission unit efficiency during operation of the embodiment of FIGS. 7-9.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1 of the drawings, the exterior structural organization of one embodiment of the invention is shown to include a housing 10 having a pair of end sections 12 and 14 joined to opposite ends of an intermediate section 16. A system input shaft is journalled centrally in the section 12 whereas a system output shaft extends rotatably from the center of the end section 14. It will be seen from FIG. 1 that the exterior configuration of the housing 10 is such that the shafts 18 and 20 lie on a common longitudinal axis midway between a pair of parallel axes 22 and 24 generally concentric with semi-cylindrical sides of the housing. These axes 22 and 24 lie on the primary axes of two I.V. transmission units housed within the intermediate section 16 and designated hereinafter as IV#1 and IV#2.
Because the functioning components of the two I.V. transmission units are alike, only the construction of IV#2 will be described with reference to the longitudinal cross-section shown in FIG. 2 of the drawings. Each of the transmission units includes a rotatable cranking body 26 journalled by bearings 28 and 30 in the frame or housing section 16 for rotation about the primary or first axis 22. A unit input shaft 32 is connected directly to the body 26 and is thus concentric with the axis 22. A nutatable body, generally designated by the reference numeral 34, is supported by bearings 36 and 38 in the cranking body 26 for rotation about a second axis 40 inclined with respect to and intersecting the first axis 22 at a point S of axes intersection. In the disclosed embodiment, the nutatable body 34 includes a central supporting shaft 42 on which a pair of oppositely convergent conical members 44 and 46 are supported for some measure of both axial and rotational movement relative to the shaft 42. A ball/ramp unit 48 is slidably keyed or splined on the shaft 42 between the cone members 44 and 46. While the unit 48 is fully disclosed in a commonly assigned co-pending application Ser. No. 926,823, filed July 21, 1978 by Harvey N. Pouliot, now abandoned to which reference may be made for structural detail, for a complete understanding of the present invention, it is necessary only to appreciate that the unit 48 functions to bias the cone members in opposite directions away from the point S in response to a torque differential between the shaft 42 and the cone members 44 and 46. It will be noted also that the conical surfaces of the members 44 and 46 are coaxial with the second axis 40 and are of a variable radius R b with respect to that axis.
The axial bias of the cone members 44 and 46 by the ball/ramp unit 48 along the shaft 42, coupled with the angular relationship of the axis 40 as well as the configuration of the conical members, causes the conical surfaces on the members 44 and 46 to be urged into engagement with a pair of axially adjustable rings 50 and 52 defining interior traction surfaces 54 and 56 which are of revolution about the primary axis 22 and of a constant radius R w . The rings 50 and 52 are secured against rotation in the frame section 16 and are fixed at the inner ends of annular piston members 58 and 60 operably positioned respectively in annular chambers 62 and 64. The chambers 62 and 64 are ported to hydraulic fluid conduits 66 and 68 in such a manner that pressurized control fluid introduced to the chambers 62 and 64 through the conduits 66 and vented from the conduit 68 will cause the pistons and thus the rings 50 and 52 to move inwardly along the axis 22 toward the point S of axes intersection. Conversely, pressurized fluid introduced through the lines 68 accompanied by an exhausting fluid from the line 66 will cause the rings to move in the opposite direction. Although not shown in the drawings, it is also possible that the rings be mechanically connected in a manner to assure synchronized movement toward and away from the point S. Also, and as shown in FIG. 1 of the drawings, the conduits 66 and 68 extend to an I.V. control unit 69 which may be any of several well-known hydraulic control units and thus, it is shown only schematically in FIG. 1.
With reference again to FIG. 2 of the drawings, each of the transmission units IV#1 and IV#2 is provided with a unit output shaft 70 journalled for rotation in an end flange or spider separating the casing sections 16 and 14 of the system. Torque transfer to the unit output shaft in a manner to be described in more detail below, is from the nutatable body 34 by way of a pinion planet 72 keyed on the shaft 42, through a reversing idler 74 carried by the cranking body 26 and to a pinion gear 76 keyed on the shaft 70.
Although the operation of the I.V. unit to transmit torque from the unit input shaft to the unit output shaft is described in the afore-mentioned co-pending application Ser. No. 706,291, an appreciation of such an operation is important to a full understanding of the transmission system of the invention. Thus, power at the unit input shaft 32 will drive the cranking body in rotation about the primary axis 22, 22 carrying the body 34 in nutation about the same axis. As a result of the frictional engagement of the conical surfaces on the members 44 and 46 with the internal traction surfaces 54 and 56 on the rings 50 and 52, together with the coupling of the members 44 and 46 through the ramp unit 48 with the shaft 42, the shaft 42 will be rotated on the inclined axis 40. The rotational velocity and direction of the cranking body 26, the nutatable body 34 and the rings 50 and 52 are related by the general equation:
ω-α+(α-β)ρ=0
In this equation, α is the speed at which the cranking member 26 is rotated about the axis 22; β is the rotational speed of the nutating body 34 and thus of the shaft 42 about the axis 40; ρ is the ratio of the radii of the external conical surfaces on the members 44 and 46 or R b to the radii on the traction surfaces 54 and 55 or R w (ρ=R b /R w ); ω is the rotational speed of the rings 50 and 52 about the primary axis 22 which in the disclosed embodiment is zero because the rings 50 and 52 are fixed to the system housing. Because of this, the general equation above-given may be simplified to
β-α(1-1/ρ)=0
In FIG. 3 of the drawings, the gears 72, 74 and 76 are shown schematically with arrows depicting the relative directions of the velocity components β and α. Also, the rotation of the gear 76 coupled to the unit output shaft is represented by the function θ. From FIG. 3, it will be seen that the gears in each of the I.V. units constitute epicyclic unit gearing in which the rotational velocity θ is a function of both α and β as well as the respective radii of the gears 72 and 76. Specifically, if the radius of the gear 72 divided by the radius of the gear 76 is equal to the function k, then the velocity components θ, α and β are related by the equation:
k=(θ-α)÷(β-α).
Because of the relationship of β, α and ρ in the equation given previously, the speed and direction of rotation at the unit output shaft 70 is related to the speed and direction of rotation of the unit input shaft or α by the equation:
θ=α(1-k/ρ).
The significance of the function k may be appreciated by reference to FIGS. 3A and 4 of the drawings. In FIG. 3A, the gears 72, 74 and 76 of FIG. 3 are replaced by 72', 74' and 76'. In this instance, the gear 72' is smaller than the gear 76' so that the function k is less than 1. In I.V. transmission units of the type illustrated in FIG. 2, moreover, the function ρ may be considered variable between a minimum value on the order of 0.5 and a maximum value of approximately 1.0. As will be appreciated from FIG. 4, therefore, if the function ρ is plotted against unit output speed θ expressed as a percentage of the input speed α, the range of unit output speed θ for three values of k will be represented by the horizontal distance between the ends of the line, k=0.6, k=0.8 and k=1.0. Moreover, it will be noted that when k equals less than 1, the direction of the velocity θ may be reversed through zero relative to the direction of unit input shaft rotation merely by adjusting the function ρ or by shifting the rings 50 and 52 toward and away from the point S of axes intersection in the embodiment described.
With reference again to FIG. 2 of the drawings, it will be noted that the end section 12 of the housing 10 encloses input gearing generally designated by the reference numberal 78 and by which the system input shaft 18 is drivably coupled with the respective unit input shafts 32. Although the complete organization of the gearing 78 is not visible in FIG. 2, its construction will be readily appreciated from the schematic drawing of FIG. 5 to be described hereinafter.
Similarly, the end section 14 of the housing 10 encloses output gearing by which the unit output shafts 70 of the respective transmission units IV#1 and IV#2 are connected to the system output shaft 20. In the particular embodiment illustrated in FIG. 2 (again incomplete because of the section illustrated in FIG. 2), the unit output of IV#2 is transmitted by gearing 80 to a shaft 82 keyed to a sun gear 84 of an epicyclic gear train 86. The output of IV#1 is transmitted by way of gearing 88 and a sleeve shaft 90 to a ring gear 92. Planet pinions 93 rotatably supported by a carrier 95 connect the gear train 86 to the system output shaft 20. The gear train 86 is therefore a form of epicyclic gearing having two inputs represented by the sun and ring gears 84 and 92 and an output represented by the planet carrier 95. Also, because the gears 84 and 92 are of different diameters, the gear reduction ratio of the unit 86 or K is less than 1. In the ensuing discussion, the reduction ratio K is assumed to be 0.6.
A more complete understanding of the gearing housed within the end sections 12 and 14 of the housing 10 as well as the operation of the described embodiment may be had by reference to FIG. 5 of the drawings in which the system is schematically illustrated. In this figure, the I.V. transmission units are illustrated in block diagram style with corresponding parts designated by the same reference numeral but primed in IV#1. In this particular embodiment of the system, the unit gearing for the two units, that is, the gears 72, 74 and 76, will approximate the respective gearing discussed above with reference to FIG. 3. In other words, both of the units IV#1 and IV#2 in FIG. 5 are provided with unit gearing in which the function k approximates 1.0.
Also in FIG. 5, the input gearing 78 is more completely shown to be constituted by a pinion gear 96 in mesh with gears 97 and 97' which may be coupled directly to the respective input shafts 32 and 32' respectively because it is possible for each of the I.V. units to be regulated in a manner such that the output shaft 70, 70' thereof will not rotate relative to the input shaft 32, 32'.
Similarly, the unit output shafts 70 and 70' are coupled directly to pinion gears 98 and 98' which mesh respectively with the above-mentioned gears 80 and 88. As a result of this organization, it will be appreciated that the unit output shaft 70' is drivably coupled to the ring gear 90 in the gearing unit 86 and that the unit output shaft 70 is drivably coupled to the sun gear 84 of the epicyclic gear train 86. In addition, a brake 99 is schematically illustrated in FIG. 5 so that the drive train associated with the sun gear 92 may be held against rotation.
Operation of the system embodiment represented by FIGS. 1-3 and 5 may be most clearly understood by reference to FIG. 6 in which curves E-1 and E-2 represent I.V. unit efficiency versus system output speed, the latter being expressed as a ratio of system input speed variable through a ratio range of from zero to unity. Three modes or modes A, B and C of system operation are represented by variable ratio ranges of system output speed with modes A and B subdivided by modes A1, A2 and B1, B2, respectively.
In mode A, the system is operated with the brake 99 engaged to prevent the ring gear 92 from rotating and with IV#1 adjusted so that the output shaft 70' thereof will transmit no torque from the input shaft 32' (i.e., ρ 1 =1). In mode A operation, thereofre, system output speed is a function of both the unit ratio of IV#2 (1-k/ρ 2 ) and of the reduction factor K of the epicyclic gearing 86 or 1/(1/K+1). Thus, if k 2 =1, as aforementioned and K=0.6, system output speed for a constant system input speed will vary from 0 for ρ 2 =1 to approximately 38 percent of system input speed. Because of the epicyclic gear reduction in this mode and the resulting reduced torque transmitting requirement of IV#2 for a given output power, the efficiency curve E-1 of IV#2 is steepened so that it reaches near maximum efficiency very quickly.
In mode B operation, the brake 99 is released and both transmission units, IV#1 and IV#2, operated so that the power transmitted from the system input shaft 18 to the system output shaft 20 is divided equally between the two I.V. units. This operation is achieved by varying ρ 1 and ρ 2 so that the function K(1-k 2 /ρ 2 ) is approximately equal to the function (1-k 1 /ρ 1 ). Specifically, in mode B operation, ρ 1 is varied from approximately 1 to 0.63 whereas ρ 2 is varied from 1.00 to 0.50 or the end limit at which the output/input ratio of IV#2 is maximum. The average efficiency of the two I.V. units operating jointly in mode B operation is reflected by the curve E-2 in FIG. 6 and is considerably lower for a given system power load at low speed operation than the curve E-1.
It will be noted from FIG. 6 that the line dividing modes A1 and A2 is selected to intersect the curves E-1 and E-2 at points where the percentage efficiency represented by the curve E-2 is approximately one-half that represented by the curve E-1. If it is assumed that the rated maximum power transmitting capacity of each of the I.V. units is one-half that of rated maximum power transmitting capacity for the system, it will be appreciated that a greater percentage of full system power can be accounted for in mode B operation, with both I.V. units splitting system power, than can be handled by one I.V. unit operating at less than twice the efficiency of either unit in mode B operation. In other words, full system output power is more nearly attained using the two I.V. units operating at an average efficiency of 45 percent, for example, than by using one I.V. unit operating at, say 80 percent because of the power transmitting capacity of each I.V. unit. For this reason, the system is controlled for operation through a relatively small range of system output speeds in mode A1 operation and then shifted to mode B operation at the point where the average efficiency of both I.V. units is more than one-half the efficiency of IV#2, alone. From FIG. 6, it will be seen also that mode B operation may continue through the substantial intermediate ratio range of the system.
As above indicated, mode B operation terminates when one of the I.V. units, specifically IV#2, reaches its maximum output/input speed ratio. The range of system operation is extended in a mode C during which IV#2 is retained at its maximum output/input ratio and IV#1 is adjusted further so that the function ρ 1 varies from 0.63 to 0.5, the maximum output/input ratio of IV#1. In mode C operation, power transmitted by the I.V. units will not be equally split with a result that IV#2 would be overworked; that is, IV#2 would be operated slightly in excess of its rated maximum power assuming an output demand for full system power. Because full system power is rarely required at maximum output speeds in actual practice, however, the potential for overworking one or the other of the I.V. units is of little or no adverse consequence in practice.
In FIGS. 7-10 of the drawings, an alternative embodiment of the invention is shown and in which the operating principles of the previous embodiments are retained in a system having speed ratio range including a directional reversal of input/output shaft rotation. In FIGS. 7-9, the I.V. transmission units are again illustrated in block diagram style with corresponding parts of each unit designated by reference numerals having the same tens and digit numbers but in a one hundred series.
Structural changes in the alternative embodiment include modification of the epicyclic gear train 186 to include as inputs from the units IV#1 and IV#2, bevel gears 192 and 184, respectively, of the same diameter. The gearing 186, therefore, is a differential gearing unit in which the function K is equal to one. Also, both input paths to the bevel gears may be retained against rotation by releasable brakes 199 and 199'. Although it is possible for both I.V. units to be adjusted to a neutral condition, the unit input shafts 132' and 132 for the I.V. units IV#101 and IV#102 are coupled to the input gearing by clutches C1 and C2, respectively, for purposes of better illustrating the respective operating modes depicted in FIGS. 7-9. Thus the clutches C1 and C2 are represented by an X when engaged and by a line when disengaged. Finally, and though not illustrated in FIGS. 7-9, the unit gearing for the two units IV#101 and IV#102 (the gears 72, 72', 74, 74' and 76, 76' in FIGS. 2, 3 and 3A) is selected to provide a reduction function k of less than one for IV#101, for example 0.8, and a reduction function k of approximately 1.0 for IV#102. In all other respects, the construction of the alternative embodiment is the same as the previously described embodiment.
In FIG. 7, the system is depicted for operation in an operational mode A1' and as such, the clutch C2 is engaged whereas the clutch C1 is disengaged. Also it will be noted that the brake 199' is engaged so that the differential bevel gear 192 will be blocked against rotation. The brake 199 is shown to be disengaged. As a result of this organization of components, the transmission unit IV#101 will be idle and all power at the input shaft 118 directed through the unit IV#102. Because the gear 192 in the differential gear 186 is locked against rotation, the output shaft 120 will be driven by rotation of the bevel gear 184 but at speeds one-half the speeds of the unit output shaft 170 due to the reduction gearing effected by the differential unit 186 in this mode of operation.
In FIG. 8, the system is depicted in an operational mode B'. In this mode, both I.V. transmission units are operative but independently regulated so that the combination of torque delivered by the outputs 170 and 170' respectively to the bevel gears 184 and 192 of the differential unit will result in the desired drive of the output shaft 120. In particular, both bevel gears 192 and 184 of the differential unit will be driven in the same direction and at varying common speeds depending on the speed of rotation desired in the system output shaft 20,
In FIG. 9, the system is illustrated in a "reverse" mode of operation and as such, the clutch C1 is engaged, the clutch C2 disengaged, the brake 199 engaged and the brake 199' disengaged. Thus, only the transmission unit IV#101 is operative in this mode. Because the unit gearing function k in IV#101 is selected to be 0.8, for example, operation of the unit IV#101 in the reverse mode will be effected by adjusting the rings 50' and 52' (FIG. 2) to cause the output shaft 170' thereof to be driven in a direction the reverse of which it was driven in the forward modes of operation. Also, the gear reduction provided by the differential unit 86 in the modes of operation will be equally applicable to operation in the reverse mode as depicted in FIG. 9 of the drawings.
Assuming that the functions ρ 1 and ρ 2 represent the speed ratio variable for the respective units IV#101 and IV#102, these functions will be adjusted independently, as above-mentioned, by the controls 69 and 69'. As will be appreciated by those skilled in the art, given the program of operation described with reference to the described system embodiments, the controls 69 and 69' may be further governed by a single master control 108 as represented schematically in FIG. 1 of the drawings. Also the various clutches and brakes may be regulated by the master control unit if such clutches and brakes are used in the system. As mentioned, the clutches may be omitted if desired to rely on the adjustability of the I.V. units to attain no rotation in the unit output shafts regardless of the speeds at which the respective unit input shafts are driven.
Operation of the system embodiment represented by FIGS. 7-9 may be appreciated further by reference to FIG. 10 in which I.V. unit efficiency is plotted against system output speed. In the efficiency curves shown in FIG. 10, it is assumed that k 1 for the unit IV#101 is again approximately 0.8 as above-mentioned, that k 2 for the unit IV#102 is approximately 1.0 and that ρ 1 and ρ 2 for the respective units varies from a minimum value of 0.5 to a maximum value of 1.0. Thus in the reverse mode of operation, system output will be driven only by the unit IV#101 and ρ 1 adjusted from approximately 1 to 0.8. In the mode A1' where the unit IV#101 is idle, the system output shaft is driven by the unit IV#102 in which the function ρ 2 may be adjusted from 1.0 to a lower value. Because of the 2:1 gear reduction provided by the differential unit 186, torque loading on the unit IV#102 during this operation is reduced, thereby steepening the efficiency curve during this mode of operation.
The transition from mode A1' to mode B' operation is again selected to correlate system output power with the operating efficiencies of the I.V. units as in the previous embodiment. In mode B' operation, the function ρ for each unit is adjusted to split system power equally between the I.V. units. Specifically, ρ 1 is adjusted between 0.8 and 0.5 while ρ 2 pis adjusted between 1.0 and 0.62, given the aforementioned system parameters. The physical result of mode B operation is that the sun and ring gears will rotate at substantially the same angular velocity with little or no rotation of the planets 93 on their respective axes. Thus the epicyclic gear train 86 operates as a direct coupling from the I.V. units to the system output shaft 20 with minimal gearing efficiency losses in mode B. Mode C' operation is the same as mode C operation of the embodiment of FIGS. 1-6.
Thus it will be seen that as a result of the present invention, a unique infinitely variable transmission system and method is provided by which the above-mentioned objects are completely fulfilled. It will be equally apparent that various modifications may be made in the embodiments disclosed herein without departure from the inventive concepts manifested by such embodiments. Accordingly, it is expressly intended that the foregoing description is illustrative of preferred embodiments only, not limiting, and that the true spirit and scope of the present invention be determined by reference to the appended claims. | An infinitely variable transmission and system in which power supplied to a system input is transmitted to a system output through at least two infinitely variable (I.V.) transmission units and an epicyclic gear train. The I.V. transmission units are independently adjustable and operable to assure an equal division of power transmitted through each unit over at least the range of systems operation where demand for maximum power is likely to occur in practice. As a result, rated power for each unit may be one-half rated full power for the system, while at the same time providing a wide range of system speed ratios. | 5 |
TECHNICAL FIELD
This invention relates to battery packs (e.g., for electric vehicles), and more particularly to inter-battery electrical connectors therefor which are removable en masse from the several batteries forming the pack.
BACKGROUND OF THE INVENTION
A number of applications (e.g., electric vehicle or stationary power sources) require that a plurality of batteries be bundled together into a battery pack to provide a specified amount of electric power. Such batteries are typically arranged on an underlying support (e.g., in a tray), and held down on the support by means of a cover that overlies the batteries and is secured (e.g., by bolts) to the underlying support. The terminals of the several batteries are electrically connected to each other (i.e., in electrical series or parallel) by means of a plurality of inter-battery connectors. When the time comes to replace or repair one or more of the batteries in the pack it has heretofore been necessary to individually disconnect the inter-battery connectors from each terminal of the batteries needing replacement/repair. Moreover, the other batteries remain electrically coupled with a high voltage output capability.
SUMMARY OF THE INVENTION
The present invention simplifies assembly and disassembly of a battery pack for repair or replacement and eliminates high voltages from the work area. The present invention contemplates the en masse disconnecting of the inter-battery connectors from the several batteries in the pack when the cover is removed from the battery pack and reconnecting of the batteries when the cover is replaced. As a result, defective batteries are readily replaceable or repairable without having to individually disconnect the connectors thereto, and the remaining batteries (i.e., which do not need repair/replacement) are electrically disconnected from each other so as to provide a low voltage working environment. More specifically, the present invention comprehends a battery pack including a plurality of batteries bundled together, each having first and second opposite polarity terminals. A plurality of inter-battery connectors electrically couple one battery to the next, and are so secured to a cover overlying the pack that removal of the cover disconnects the several connectors en masse from their associated-battery terminals. The inter-battery connectors each have a first coupler at one end thereof slideably, but snugly, engaging a terminal on one of the batteries and a second coupler on another end thereof slideably, but snugly, engaging a terminal on another of the batteries. Preferably, each coupler will constrictively engage a terminal stud on the battery to which it is coupled. The cover includes a plurality of retainers which engage and secure the inter-battery connectors to the cover with sufficient strength that all of the connectors will disengage from their respective battery terminals when the cover is removed from the pack. Preferably, the cover detachably secures the connectors thereto such that the connectors can be readily removed from the cover as needed. Most preferably, the batteries will be supported on an underlying support, and the cover secures (e.g., as by bolting) the pack to the support. The inter-battery connectors preferably comprise a rigid strap, and the cover has a plurality of protuberances extending from its underside to engage and secure the strap to the cover. Most preferably, the protuberances each include a lip which underlies an edge of the inter-battery connector strap to secure the strap to the underside of the cover.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The invention will better be understood when considered in the light of the following detailed description of a preferred embodiment thereof which is given hereafter in conjunction with the several figures in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded isometric view of part of a battery pack in accordance with the present invention;
FIG. 2 is a fully assembled isometric view of the battery pack of FIG. 1;
FIG. 3 is an isometric view of the underside of the battery cover of FIGS. 1 and 2 in accordance with the present invention;
FIG. 4 is a sectioned isometric view of a coupler on the end of an inter-battery connector;
FIG. 5 is a view in the direction 5--5 of FIG. 2;
FIG. 6 is a view in the direction 6--6 of FIG. 2; and
FIG. 7 is a view in the direction 7--7 of FIG. 2.
The Figures depict a battery pack 2 comprising a plurality of individual batteries 4 supported in an underlying support/tray 6. Each battery 4 has a pair of opposite polarity terminals 8 and 10. In the particular embodiment shown, the terminals 8, 10 comprise upstanding threaded bolts 12 (see FIG. 7), though other configurations are possible. An adaptor 14, having a smooth cylindrical outer surface 16, is screwed on to the bolt 12 to provide an upstanding stud 15 for connecting to an inter-battery connector 18. Alternatively, the adaptor 14 could be eliminated and the bolt 12 replaced by a smooth-sided stud. The inter-battery connector 18 preferably comprises a rigid strap 20 having a coupler 22 and 24 on each end thereof for constrictively engaging the adaptor 14. The strap 20 preferably has apertures 56 and 58 therein for receiving the couplers 22 and 24 which are brazed or crimped therein, as best shown in FIG. 7. A cover 26 overlies the several batteries 4 and includes flanges 28 that receive bolts 30 extending from mountings 32 in the tray 6 for anchoring the cover 26 to the tray 6 to thereby secure (i.e., hold down) the several batteries 4 in the tray 6. The tray 6 includes laterally extending mounting flanges 28 and 30 for mounting the battery pack where needed (e.g., to the frame of an electric vehicle).
The rigid strap 20 forms the inter-battery electrical connector 18 and has a pair of couplers 22 and 24, in the form of sleeves thereon adapted to slip over, and mate with, the studs 15. The coupler sleeves 22 and 24 slideably fit snugly over the studs 15 to provide good electrical contact therewith while, at the same time, being readily removable therefrom by applying a modest upward force thereto. To this end, the insides 26 and 28 of the couplers 22 and 24 are lined with commercially available hyperbolic or helical terminals, and preferably with hyperbolic/helical terminals sold by the RADSOC Company. Hyperbolic/helical liners 30 provide excellent electrical contact yet readily slip on and off their associated terminals. Such liners 30 preferably comprise a plurality of wires 33 separated by slots 34 which are joined together at their ends 36 and 38, as best shown in FIG. 4. The several wires 33 are preferably skewed relative to the center axis of the liner 30 so as to provide a helix. This is conveniently accomplished by twisting the liner 30 which also causes its longitudinal center to become necked down at the reduced diameter zone 42 such that the liner takes on a hyperbolic shape. Such liners are capable of expanding radially to snugly and constrictively engage the studs 15 without requiring excessive force to attach or remove them from their associated studs. The necked down portion 42 of the liner 30 is smaller than the outside diameter of the stud 15, but is readily expansible when the stud 15 is inserted therein. Once expanded, the liner will constrictively engage the smooth outer surface 16 of the stud 15 over substantially the entire length thereof hence resulting in a low resistance electrical connection therebetween. Preferably, the wires 33 that make up the liner 30 are flat so that a large surface area thereof will engage the adaptor stud 15 for excellent low-resistance contact therebetween.
In accordance with the present invention, the inter-battery connector straps 20 are secured to the cover 26 with sufficient strength that upon lifting the cover 26 from atop the battery pack 2, the couplers 22 and 24 will become disengaged from the studs 15 without disengaging the connector strap 20 from the cover 26. To this end, the cover 26 includes a plurality of retainers, in the form of protuberances 44 and 46, which engage the strap 20 and hold it to the underside of the cover 26. The protuberances 44 each include a shelf 48 which underlies the edge 50 of the strap 20. Similarly, the protuberances 46 each include a shelf 52 underlying the edge 54 of the strap 20 (as best shown in FIG. 7). To properly locate the straps 20 on the cover 26 so as to insure that their couplers 22 and 24 are properly registered with their mating studs 15, the straps 20 are first positioned on the batteries 4. Thereafter, the cover 26 is pressed on to the top of the battery pack 2 so as to cause the inter-battery connector straps 20 to snap into place of the shelves 48 and 52 of the protuberances 44 and 46 respectively. Thereafter, when the cover 26 is lifted from the batteries 4, the straps 20 will remain with the cover 26 and all of the batteries are electrically disconnected from each other, en masse. The straps 20, however, may be readily removed from the cover 26 by prying or pulling them away from the shelves 48 and 52 that engage them. Other techniques (e.g., bolts) may be-used to secure the inter-battery connector straps 20 to the cover 26 in a manner such that the straps 20 may be detached from the cover 26 when so desired.
The cover 26 will preferably comprise a lightweight, grate-like, structure molded (e.g., vacuum formed) from a glass-fiber-filled plastic such as polypropylene, although other materials and methods of construction may also be employed. The cover 26 includes inverted U-shaped rails 58 extending from one side thereof to the other which provides strength without excessive weight. The cover 26 includes sockets 60 which loosely receive the couplers 22 and 24 therein, and substantially insulate them from inadvertent electrical shorting. Some clearance is provided between the outside of the couplers 22 and 24 and the inside of the sockets 60 to allow room for longitudinal movement of the strap 20 therein as may be needed to properly register the couplers 22 and 24 with respect to their associated studs 15 during placement of the cover 26 atop the batteries 4. Cross members 62 extend between the rails 58, and include depending tapered legs 64 which are adapted to fit between the several batteries 4 in the stack (see FIG. 6), and serve to align the cover 26 with the batteries 4 during placement of the cover 26. Openings 66 in the cover 26 between the rails 58 and cross members 62 permit air to circulate between the batteries 4 for cooling and/or heating, as may be necessary.
While the invention has been disclosed primarily in terms of specific embodiments thereof it is not intended to be limited thereto but rather only to the extent set forth hereafter in the claims which follow. | A battery pack including a cover overlying a plurality of individual batteries and a plurality of inter-battery connectors for electrically coupling the several batteries together. The inter-battery connectors are secured to the cover such that upon removal of the cover all of the connectors are removed from the batteries en masse. | 1 |
FIELD OF THE INVENTION
This invention relates to a differential amplifier containing therein a low-pass filter, and more particularly to a differential amplifier containing therein a low-pass filter and used for a weight detection circuit at a load cell weighing scale.
BACKGROUND OF THE INVENTION
The conventional weight detection circuit for the load cell weighing scale, as shown in FIG. 1 is adapted to amplify by a high input impedance type differential amplifier 2 an output of a bridge circuit 1 of strain gauge resistances for the load cell, that is, analog voltage proportional to the weight, so that the output is fed into an analog-to-digital converter 4 through a low-pass filter 3. Here, the low-pass filter 3 is necessary for reducing vibrations and noises produced by mechanical and electrical factors and the differential amplifier 22 is indispensable for differential amplification of a weight signal from the bridge circuit 1 of load cell (wherein the differential amplifier serves as a part of the high input impedance type differential amplifier). It will of course increase the number of operational amplifiers to constitute the low-pass filter 3 and differential amplifier 22 separate from each other. Hence, there is a defect of increasing the hazard rate and being expensive to produce.
SUMMARY OF THE INVENTION
In the light of the above problems, this invention has been designed. A differential amplifier of the invention has at the preceding stage resistances and condensers connected in combination so as to function as the low-pass filter, and also operates as the secondary low-pass filter when given the output of the senser, such as the bridge circuit of load cell, thereby simultaneously demonstrating the function as the differential amplifier as the same as the conventional one.
Even when given the output directly from the bridge circuit of load cell not through the high input impedance type amplifier, the differential amplifier of the invention functions as the secondary low-pass filter in relation to each strain gauge resistance of the bridge circuit of load cell, in which its function as the differential amplifier will of course be demonstrated.
An object of the invention is to provide a differential amplifier which can simplify a circuit for digitalconverting the output from various sensors, such as the bridge circuit for the load cell and disposed between the sensor and an analog-to-digital converter.
These and other objects of the invention will become more apparent in the detailed description in accordance with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a circuit diagram of a weight detection circuit of the conventional load cell weighing scale,
FIG. 2 is a circuit diagram of an embodiment of a differential amplifier of the invention, and
FIGS. 3 and 4 are circuit diagrams exemplary of the weight detection circuits at the load cell weighing scale, to which the circuit of the invention is applied, in which
FIG. 3 is a circuit diagram of the differential amplifier of the invention, which is connected to a bridge circuit of load cell through a high input impedance type amplifier, and
FIG. 4 is a circuit diagram of the same, which is connected directly to the bridge circuit of load cell not through the high input impedance type amplifier.
DETAILED DESCRIPTION OF THE INVENTION
Paying attention to that the low-pass filter and the differential amplifier both include operational amplifiers, this invention has been designed and will be detailed in the following description in accordance with the drawings.
FIG. 2 shows an embodiment of the invention, in which a filter unit B to be discussed below is added to a conventional differential amplifier and resistances and capacity of each condenser in use are under a fixed condition.
At first, a first resistance R a is interposed between a negative input terminal of an operational amplifier (OP) and the node P 1 of an input resistance R i and feedback resistance R f at the differential amplifier, and is grounded at the input resistance R i side through a first condenser C a and connected at the OP's negative input side to the output line of the operational amplifier through a second capacitor C b .
A second resistance R b is connected to between the node P2 of a not-grounded voltage-dividing resistance R d1 and grounded voltage-dividing resistance R d2 and the positive input line of the operational amplifier (OP), and is grounded at the voltage-dividing resistances R d1 , R d2 side through a third condenser C c and at the OP's positive input line side through a fourth condenser C d .
Furthermore, an input resistance R i is made equal to not-grounded voltage-dividing resistance R d1 , a feedback resistance R f equal to grounded voltage-dividing resistance R d2 first resistance R a equal to second resistance R b , capacity of first condenser C a equal to that of third condenser C c , and capacity of second condenser C b equal to that of fourth condenser C d , as R i =R d1 =R 1 , R f =D d2 =R 2 , R a =R b =R 3 , C a =C c =C 1 and C b =C d =C 2 .
The differential amplifier containing the low-pass filter, constructed as foregoing, generally uses the high input impedance type amplifier connected to the preceding stage of the differential amplifier as exemplary in FIG. 3.
FIG. 3 shows the differential amplifier applied to a weight detection circuit for a load cell weighing scale, in which the output of the bridge circuit 1 for the load cell is given through the high input impedance type amplifier 21 to the differential amplifier containing the low-pass filter. The high input impedance type amplifier, when used in the above circuit constitution, functions to cancel the mutual influence between the bridge circuit 1 and the differential amplifier, thereby facilitating the design as discussed below.
Now, the node equation is set up at each node and Laplace-transformed, then a complex (frequency region) function Vout(S) is obtained as: ##EQU1## where V1, V2: Output voltage of high input impedance type amplifier, and
S: Complex variable (Laplace operator).
Since the denominator of Equation (1) is the secondary function of S, this circuit can be seen to operate as the secondary low-pass filter.
Equation (1), in a direct current fashion, becomes
V.sub.out =R.sub.2 /R.sub.1 (V1-V2) . . . (2),
whereby the function as the differential amplifier is quite the same as before addition of the filter unit B. Hence, in this case, there is no need of making uniform the temperature characteristics of resistances R1, R2 and of each strain gauge at the bridge circuit 1, but it is enough to make uniform the temperature characteristics (a) input resistance R i and feedback resistance R f and (b) voltage dividing resistances R d1 and R d2 , at each group of (a) and (b).
Consequently, various sensors are available instead of the bridge circuit 1 as far as this invention is generally used as the above.
Now, in a case of using the differential amplifier of the invention containing the low-pass filter and connected to the bridge circuit 1 of load cells, even when the high input impedance type amplifier is omitted as shown in FIG. 4, the functions as the low-pass filter and differential amplifier are demonstrated in relation to the bridge circuit 1.
The node equation is set up at each node at the circuit in FIG. 4 and is Laplace-transformed, then the complex (frequency region) function V' out (S) of the FIG. 4 circuit is obtained as: ##EQU2## where V a , V b : Applied voltage to bridge circuit,
R g , R b : Each strain gauge resistance in bridge circuit, and
R 0 : Temperature compensating resistance of load cell.
Since Equation (3) has the denominator of the secondary function of S, it can be seen that this circuit operates as the low-pass filter, where Equation (3), as seen in comparison with Equation (1), contains strain gauge resistances R g , R h or temperature compensating resistance R 0 at the bridge circuit 1, whereby it can be seen to operate as the low-pass filter in relation to the bridge circuit 1. The amplification factor for the differential amplifier similarly relates to the strain gauge resistance of bridge circuit 1.
Namely, in a direct current fashion, ##EQU3## where R: Values of strain gauge resistances R g , R h during no load.
Accordingly, in the above case, it is necessary to make uniform the temperature characteristics of all the strain gauge resistances R g , R h and resistances R i , R f , R d1 , R d2 , R a , and R b at the differential amplifier.
As seen from the above, the differential amplifier of the invention, which contains the low-pass filter, is advantageous in saving the number of operational amplifiers, keeping less hazard rate, and lowering the manufacturing cost. Especially, the differential amplifier, when connected directly with the bridge circuit of load cell, can omit the high input impedance type amplifier, thereby further improving the above effect.
While preferred embodiments of the invention have been described using specific terms, such description is for illustrative purpose only, and it is understood that changes and variations may be made without departing from the spirit or scope of the following claims. | A differential amplifier which incorporates at its preceding stage resistances and condensers combined with each other and serving as a low-pass filter, thereby omitting a conventional low-pass filter separate from a differential amplifier provided at a weight detection circuit for a load cell weighing scale or other detection circuit. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of and claims priority to U.S. patent application Ser. No. 11/042,472 also entitled “VASCULAR SHEATH”, filed on Jan. 24, 2005, which application claims priority to U.S. Provisional Application Ser. No. 60/538,712, filed Jan. 23, 2004, by inventor John C. Opie, both of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to medical systems and methods, and more particularly, to a vascular sheath to assist in preventing excessive bleeding during certain medical procedures.
BACKGROUND OF THE INVENTION
[0003] This invention relates to vascular sheaths (preferably larger diameter sheaths) having an improved hemostatic valve or gasket assembly to assist in preventing excessive bleeding when the sheath is “dormant.” “Dormant” in this context means that the sheath is temporarily transmitting and/or retaining a small diameter secondary device such as a medical guide wire (also referred to herein as a guide wire or wire), or diagnostic catheters for procedures such as serial angiograms.
[0004] Vascular sheaths (also referred to herein as a sheath or vascular access sheath) are delivery platforms used to introduce secondary devices into blood vessels. These secondary devices include, for example, dilators, guide wires, angioplasty balloons, stents, atherectomy catheters, angiography catheters and abdominal aortic aneurysm endo-luminal grafts. The sheaths usually range from a diameter of about 5-French to 24-French (“Fr”) depending upon the size of the secondary device. The upper limit is dictated to some extent by human anatomy, particularly the size of the femoral artery.
[0005] Known sheaths work relatively well and are substantially hemostatic when used with relatively large indwelling secondary devices. However, when known sheaths are used with a relatively small diameter secondary device, such as a guide wire, they typically leak sizable quantities of blood. This is due to the efficiency of the cruciate slits typically found in the elastomeric (usually a silicone rubber) gasket that is used in known sheaths to form a seal. Using the example of a guide wire, the wire tends to slip into one of the slits creating a small eye-shaped opening in the slit and bleeding occurs through the opening. Because of this, it is common to put a second sheath, usually of 10 -French diameter, over the wire and into the larger sheath to create a seal and stop the bleeding. In some instances a glob of wax is used to plug the end of the sheath.
[0006] One solution to this problem has been suggested by the Touhey-Borst system, which is known in the art. However, that system does not perform well when large bore secondary devices (such as large bore obdurators) are removed from large bore sheaths and only wires or catheters remain. The Touhey-Borst valve construction includes an O-ring seal that is compressed during use. However, the O-ring is contained statically within the distal end of a second chamber. Such a mechanism is unable to seal a large bore secondary device, and after the large device is removed, then seal down against a small diameter secondary device, such as a wire or angiocatheter. This is due to the fact that only so much compression is available with the non-moving O-ring.
[0007] Other methods have been developed to solve this problem and have not been entirely successful. Some sheaths include two or even three elastomeric gaskets, but blood still leaks when only the wire passes through the sheath. Other sheaths include torroidal balloons. Torroidal balloons may work but are cumbersome and when a large secondary device is removed from the sheath one must quickly inflate the balloon with a syringe to avoid a sudden and large blood loss via the large opening through the balloon.
[0008] Other devices have suggested iris-type valve assemblies, but these have not been widely used due to the expense of making them and the potential problem of engaging them or disengaging them with resultant transient torrential femoral artery bleeding. Still other inventors have devised flapper valve mechanisms.
SUMMARY OF THE INVENTION
[0009] The invention is a vascular sheath that permits the passage of a secondary device into a blood vessel, such as the femoral artery. In accordance with the present invention, an improved vascular access sheath is provided to facilitate the introduction of both large and small diameter secondary devices into a vein or artery, while assisting to prevent significant blood loss, even when the sheath only transmits a relatively small secondary device, such as a medical guide wire.
[0010] The sheath includes a body and a primary seal retained in the housing. The primary seal has a lumen passing therethrough and the secondary device passes through the lumen. As the primary seal is compressed (which is preferably done by tightening a cap on the body, wherein the cap is attached to a post that presses against the primary seal) at least part of the lumen is compressed and substantially presses against the outer surface of the secondary device to form a seal. In this manner, the sheath can seal against both relatively large diameter devices and relatively small diameter devices.
[0011] The sheath also preferably includes one or more secondary seals. The preferred secondary seal is a flexible disk having one or more slits through which the secondary device can pass.
[0012] A vascular access sheath according to the invention is preferably is a large bore vascular access sheath of a size between 5 Fr and 24 Fr.
[0013] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed.
[0014] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate one or more preferred embodiments of the invention and together with the description, serve to explain the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a cross-sectional, side view of a cap for a vascular sheath according to the invention.
[0016] FIG. 2 is a top view of the cap of FIG. 1 .
[0017] FIG. 3 is a partial cross-sectional, side view of a primary seal for a sheath according to the invention.
[0018] FIG. 4 is a cross-sectional, side view of a body of a vascular sheath according to the invention.
[0019] FIG. 5 is a side view of a secondary device that may be used with the invention.
[0020] FIG. 6 is a cross-sectional, side view of a vascular sheath according to the invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0021] Reference will now be made in detail to the preferred exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings.
[0022] As used herein, “distal” refers to being more distant to the operator (usually a surgeon) and closer to the interior of the patient's blood vessel, wherein “proximal” means closer to the operator and further from the interior of the patient's blood vessel.
[0023] FIG. 1 is a cross-sectional, side view of a cap 1 showing a central post 6 and an enclosed thread 4 to threadibly engage a matching thread of body 30 of the vascular sheath 100 (see FIG. 6 ). The purpose of cap 1 is to seal sheath 100 and, in particular, to compress primary seal (or O-ring) 20 , and any suitable structure may be used for this purpose. In this embodiment cap 1 is generally circular in shape.
[0024] Cap 20 is preferably comprised of injection molded plastic such as polyethylene, polypropylene or vinyl, but may be of any suitable material and manufactured using any suitable technique.
[0025] Central post 6 extends outward and has a flange or ridge 7 to which secondary seal 8 is preferably attached. Cap 1 has a distal end 1 A and a proximal end 2 . Wall 3 of cap 1 and enclosed thread 4 are designed to engage a matching thread 37 of body 30 , which is best seen in FIG. 6 .
[0026] A central lumen 5 of post 6 extends from the base of cap 1 to the distal end of cap 1 . Lumen 5 of post 6 is large enough to permit the passage of a secondary device, such as a large obdurator, an example of which is shown in FIG. 5 . Bore 5 may have a diameter of, for example, 16 Fr, 18 Fr, 20 Fr, 22Fr, or 24 Fr. A secondary seal, as shown, is gasket 8 , which has a slit or slits or other opening through which the secondary device may pass. Gasket 8 is preferably made of elastomeric silicone rubber although any suitable material may be used. In order to house gasket 8 , proximal end 2 of cap 1 has a chamber 10 that receives gasket 8 . Chamber 10 is preferably permanently closed once gasket 8 is positioned therein, but could be formed to open so that gasket 8 could be removed and changed. Angled edge 11 of cap 1 is optional and assists to facilitate centering of a secondary device (not shown in this Figure) passed through cap 1 .
[0027] FIG. 2 is a top view of cap 1 and shows gasket 8 and the encircling edge or wall 11 A that retains gasket 8 . A circular lateral wall 14 on cap 2 retains gasket 8 laterally. As shown, a guide wire 50 passes through one or more slits 12 in gasket 8 . The small eye-shaped defect E is, in this embodiment, the opening through which bleeding can occur. The slits 12 in gasket 8 are the openings through which a secondary device passes and these seal against the secondary device to help prevent bleeding. The distortion of these slits 12 (such as by a thin wire or angiocatheter) is how bleeding occurs with small-diameter secondary devices in relatively large bore vascular sheaths.
[0028] FIG. 3 is a view of the primary seal 20 , which as shown is a modified O-ring that fits over flange 7 of cap 1 . Seal 20 has a proximal end 21 and a distal end 22 with respect to the device and a body component 23 . Seal 20 has a lumen (not shown) passing therethrough, the lumen sufficiently large to allow a secondary device to pass therethrough. Primary seal 20 is configured such that when mounted as part of sheath 100 , and when compressed, at least part of the lumen constricts to substantially seal against the outer surface of a secondary device that may be present in the lumen. Seal 20 is preferably injection molded and made of elastomeric, silicone rubber, although any suitable material or method of manufacture may be utilized.
[0029] Proximal end 21 of seal 20 has a matching groove 25 and flange 26 to receive flange 7 of post 6 of cap 1 , and post 6 compresses seal 20 when cap 1 is tightened on body 30 although any method or structure may be used to compress seal 20 . Body part 23 of seal 20 has a conical distal end 27 that fits into a funnel chamber 31 of body 30 of vascular sheath 100 . Seal 20 is sufficiently long and preferably has a crease and/or narrow diameter portion to allow seal 20 to collapse and further reduce the size of its lumen to accommodate small sized secondary devices such as guide wires or an angio-catheters.
[0030] FIG. 4 is a cross-sectional view of a body 30 of the vascular sheath 100 . Body 30 has a central chamber 31 , which during use is preferably connected to a pressure line supporting a three-way stopcock for flushing, angiography or pressure monitoring while the sheath in place. Central chamber 31 receives seal 20 , as shown in FIG. 6 . The distal part 31 A of chamber 31 is cone or funnel shaped, and has a wall 32 designed to receive the cone shaped distal end 27 (see FIGS. 3 and 6 ) of seal 20 . Distal to chamber 31 is a second chamber 33 that is connected to an opening 34 . Opening 34 feeds into a pressure line 35 , which in turn is connected to a three-way stopcock (not shown) for access to the body 30 as required for such things as flushing, sampling, angiography via the vascular sheath, and taking hemodynamic measurements.
[0031] In this embodiment, external to central chamber 31 is external thread 37 that receives inner thread 4 of cap 1 , so that cap 1 can be engaged and advanced or retracted on body 30 thus increasing or decreasing the compression on seal 20 , and thus compressing or opening at least part of the lumen of seal 20 , when desirable.
[0032] A rim 38 , which is preferably circular, closes the chambers 31 and 33 from the air and connects to external sheath tube 39 . Sheath tube 39 extends away from body 30 for an appropriate distance so that it can enter the blood vessel a distance required by the procedure being undertaken, for example, as far as the distal abdominal aorta or approximately as far as the orifices of one or both renal arteries and all positions in between from an entrance position at the common femoral artery.
[0033] The distal end 40 of sheath tube 39 preferably has a chamfered wall 41 so that it presents a low profile to produce little damage to the blood vessel wall when being inserted into the blood vessel. A small radio-opaque ring (not shown) preferably exists at end 40 so as to provide the operator with a x-ray visual understanding as to the precise position of the distal end of the sheath at all times during the procedure.
[0034] FIG. 5 is a side view of a secondary device, which in this case is an obdurator 41 , that may be used with the invention. Obdurator 41 has a tapered distal end 41 A, which ends in a tip 41 B. A lumen 42 runs the entire length of obdurator 41 so that obdurator 41 can be passed over a guide wire. Body 43 of obdurator 41 is sized to match with an appropriately sized vascular sheath for a substantially hemostatic fit. In this example, the proximal end 41 of obdurator 44 is fitted with a Luer lock and gripping section 45 for easy grasping and removal or introduction.
[0035] FIG. 6 shows a preferred embodiment of an assembled vascular sheath 100 according to the invention. Sheath 100 has guide wire 50 passing therethrough, and, as shown, seal 20 is uncompressed. As cap 1 is screwed down on body 30 , deformable (or compressible) body 23 of seal 20 will collapse to some degree and cone 27 will be pressed inward by pressure exerted by wall 32 . At least part of the lumen of seal 20 will be forced to fully or substantially compress around the guide wire 50 . Thus the small eye deformity (see FIG. 2 ) produced by wire 50 in gasket 8 will not leak blood because the blood is sealed by primary seal 20 .
[0036] In summary, when a large diameter vascular sheath transmits a large secondary device, bleeding is usually not a major problem. However, to prevent bleeding when the large secondary device has been removed and the sheath only retains a small secondary device, such as a thin guide wire, the primary seal 20 should be compressed, thus fully or substantially compressing the lumen of seal 20 around the outside of the smaller secondary device to prevent bleeding. If a large secondary device needs to be reinserted the primary seal 20 is allowed to relax thereby opening its lumen.
[0037] Also, it is possible to increase the number of disk gaskets (in the preferred embodiment there is only one, gasket 8 ) and/or vary the style of slits from four to three or even one or possibly include a small single circular hole in one or more disk gaskets.
[0038] Another benefit that may be derived from the preferred embodiment of the invention is that it is simple to ship and store, and is fully assembled. The only step required is to flush the chamber access post via the side branch, which had a three-way stopcock at its end.
[0039] While this invention has been described in terms of its preferred embodiments and various modifications those skilled in the art can appreciate that other modifications can be made without departing form the spirit and scope of this invention. Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the ultimately-filed claims. | Disclosed is a vascular sheath for helping to prevent bleeding during procedures in which devices must be inserted into a blood vessel such as an artery or vein. The vascular sheath includes at least one manually compressible primary seal that has a lumen passing therethrough. A device inserted into the blood vessel first passes through the sheath, and thus through the lumen in the primary seal. By manually adjusting the compression of the primary seal the size of at least part of the lumen is made to substantially conform to the outer surface of the device. The primary seal can thus seal against large and small sized devices to prevent bleeding. It is preferred that a secondary seal also be used and one type of secondary seal is a flexible disk or flap with one or more slits through which the device passes. | 0 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the priority of German Application No. 100 41 894.5 filed Aug. 25, 2000, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] This invention relates to a method of directly determining setting values for the application point of regulation in a regulated draw frame for fiber material. The control system of the draw frame in which the extent of draft of the sliver may be set has at least one preliminary control system for changing the draft of the sliver. Based on the drafted sliver, a number of quality-characterizing measured values, such as CV values may be sensed and utilized for formulating a function whose minimum represents an optimum application point of regulation for the control of the draw frame. The optimized application point of regulation may be determined in a pre-operational test run or a setting run of the draw frame.
[0003] The application point of regulation is an important setting magnitude in a draw frame to produce slivers with a high sliver uniformity, that is, with a small CV value.
[0004] In a known system, during a pre-operational setting run, the sliver is drafted between the mid rolls and the output rolls of the draw unit and is withdrawn by calender rolls which are adjoined by a measuring device for the CV value of the drafted sliver. In the pre-operational setting run a plurality of CV values are determined which represent a quality-characterizing magnitude for the drafted sliver. Based on such measured values, a function is formulated whose minimum value corresponds to a value which promises to be the best adaptation of the regulation actual sliver. The plurality of measured values which are plotted and based on which the function is formulated, are in each instance measured for a different setting value of the regulation. Thus, for the definition of the function to be evaluated, each incremental value of an incrementally changing parameter, for example, the application point of regulation of the “electronic memory”, has to be associated with one of the measured values.
[0005] It is a disadvantage of the above-outlined system that the quality of the un-drafted sliver entering the draw unit cannot be taken into consideration. It is a further drawback that only one certain CV value is considered.
SUMMARY OF THE INVENTION
[0006] It is an object of the invention to provide a method of the above-outlined type from which the discussed disadvantages are eliminated and which in particular improves the determination and setting of the optimal application point of regulation in a regulating device of the draw unit.
[0007] This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, the method of directly determining setting values for an application point of regulation in a draw unit for drafting sliver includes the following steps: obtaining a plurality of measured values of a quality-characterizing magnitude, such as a CV value, of the drafted sliver; utilizing the measured values for formulating a function having a minimum constituting an optimal application point of regulation for controlling the draw unit; determining the optimal application point of regulation in a pre-operational run of the draw unit; obtaining measured values of at least two quality-characterizing magnitudes based on the drafted sliver; combining values of the quality-characterizing magnitudes at the sliver, which correspond to one another with respect to the application point of regulation, to a quality-characterizing number QK, and forming a function based on several numbers QK. The function has a minimum corresponding to an optimal application point of regulation R opt .
[0008] The optimal application point of regulation (optimal dead period or delay) is determined by the draw frame itself by using the steps according to the invention. By utilizing different quality-characterizing magnitudes, such as CV values, the application point of regulation is determined in a more accurate manner. Further, a more rapid determination of the application point of regulation is made possible.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] [0009]FIG. 1 is a schematic side elevational view of a regulated draw frame including a system for practicing the invention.
[0010] [0010]FIG. 1 a is a block diagram of a separate preliminary control device.
[0011] [0011]FIG. 2 is an enlarged schematic side elevational view of one part of the FIG. 1 structure, illustrating the principal drafting field with indication of the principal drafting point.
[0012] [0012]FIG. 3 is a diagram illustrating the effect of the application point of regulation on the on-line CV value.
[0013] [0013]FIG. 4 illustrates a visual representation of an automatic determination of the optimal application point of regulation.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0014] [0014]FIG. 1 illustrates a draw frame 1 which may be, for example, an HSR model manufactured by Trützschler GmbH & Co. KG, Mönchengladbach, Germany.
[0015] The draw frame 1 includes a draw unit 2 having an upstream draw unit inlet 3 and a downstream draw unit outlet 4 . The slivers 5 are taken from non-illustrated coiler cans and are introduced into a sliver guide 6 which includes a measuring member 9 and from which they are withdrawn by calender rolls 7 , 8 .
[0016] The draw unit 2 is a 4-over-3 construction, that is, it is formed of a lower output roll I, a lower middle roll II and a lower input roll III as well as four upper rolls 11 , 12 , 13 and 14 . The draw unit 2 drafts the sliver 5 ′, composed of a plurality of slivers 5 , in a preliminary and principal drafting field. The roll pairs III, 14 and II, 13 constitute the preliminary drafting field whereas the roll assembly II, 11 , 13 and the roll pair I, 12 constitute the principal drafting field. The roll pair II, 13 is immediately followed by a pressure bar 30 . The drafted slivers 5 are introduced in the draw unit outlet 4 into a sliver guide 10 and are, by means of calender rolls 15 , 16 , pulled through a sliver trumpet 17 in which the slivers are combined into a single sliver 18 which is subsequently deposited in coiler cans. The direction of the sliver passing through the draw frame 1 is designated at A.
[0017] The calender rolls 7 , 8 , the lower input roll III and the lower middle roll II which are mechanically coupled to one another, for example, by means of a toothed belt, are driven by a regulating motor 19 to which a desired rpm value may be applied. The respective upper rolls 14 and 13 are driven by the respective lower rolls by friction. The lower output roll I and the calender rolls 15 , 16 are driven by a principal motor 20 . The regulating motor 19 and the principal motor 20 each have a respective regulator 21 , 22 . Each rpm regulation occurs by means of a closed regulating circuit which includes a tachogenerator 23 connected with the motor 19 and the regulator 21 , as well as a tachogenerator 24 connected with the motor 20 and the regulator 22 .
[0018] At the draw unit inlet 3 a mass-proportionate magnitude, for example, the sliver cross section is measured by the inlet measuring organ 9 which is known, for example, from German patent document DE-A-44 04 326. At the draw unit outlet 4 the cross section of the exiting sliver 18 is sensed by an outlet measuring member 25 which is associated with the sliver trumpet 17 and which is known, for example, from German patent document DE-A-195 37 983. A central computer unit 26 (control and regulating device), for example, a microcomputer with microprocessor, transmits a setting of the desired value to the regulator 21 for the regulating motor 19 . The measured values from both measuring members 9 and 25 are transmitted to the central computer unit 26 during the drafting process. The desired rpm value for the regulating motor 19 is determined by the central computer unit 26 from the measured values sensed by the intake measuring member 9 and from the desired value for the cross section of the exiting sliver 18 . The measured values of the outlet measuring member 25 serve for monitoring the exiting sliver 18 . With the aid of such a regulating system fluctuations in the cross section of the inputted slivers 5 may be compensated for by suitable regulation of the drafting process to obtain an evening of the sliver. A monitor 27 , an interface 28 , an inputting device 29 and a memory 31 are also connected to the computer 26 .
[0019] While the preliminary control system may be integrated into the central computer unit 26 as shown in FIG. 1, according to FIG. 1 a, a separate preliminary control system 33 may be provided which is connected between the computer unit 26 and the regulator 21 . The computer unit 26 changes the application point of regulation R of the preliminary control system 33 .
[0020] The measured values, for example, thickness fluctuations of the sliver 5 , obtained from the measuring member 9 are applied to the memory 31 with a variable delay. As a result of such a delay the change in the draft of the sliver in the principal drafting field according to FIG. 2 occurs at a moment when the sliver region measured earlier by the measuring member 9 and deviating from the desired value is situated in the principal drafting point 32 . When such a sliver region reaches the principal drafting point 32 the respective measured value is called from the memory 31 .
[0021] The distance between the measuring location of the measuring member 9 and the drafting location at the principal drafting point 32 is the application point of regulation R.
[0022] The apparatus according to the invention makes possible a direct determination of the setting values for the application point of regulation R. A plurality of measured values of the sliver thickness for different lengths of the exiting sliver 5 ′″ (drafted sliver) are taken from the measuring member 25 in the sliver trumpet, and three CV values (CV 1m , CV 10cm , CV 3cm ) are calculated as quality-characterizing magnitudes. In a similar manner the measuring member 9 in the sliver guide 6 takes thickness measurements of a determined length of the undrafted sliver 5 , and from these measured magnitudes quality-characterizing CV values (CV in ) are calculated. The determination of the CV values occurs preferably for four application points of regulation R. Expediently, in each instance two application points of regulations R are selected on the one side and two application points of regulation R are selected on the other side of the optimal application point of regulation R opt . In each instance a quality-characterizing number QK is determined by calculation from the CV values of the un-drafted sliver 5 and the drafted sliver 5 ′″. Further, a function between the numbers QK and the corresponding application points of regulation R are calculated in the computer 26 and displayed on the screen 27 (FIGS. 3 and 4). A polynomial of the second degree is determined from the four values of the application point of regulation R and the respective quality-characterizing numbers QK, and subsequently the minimum of the curve is calculated. The minimum point of the function corresponds to the optimum application point of regulation R opt (see FIG. 4). In this manner, based on the drafted sliver 5 ′″, several measured values of three different CV values and based on the un-drafted sliver 5 , several measured values of a CV value are utilized, and those CV values which correspond to one another in relation to the application point of regulation R are combined to a quality number QK. Based on several quality numbers QK a function is formulated by computation, whose minimum point corresponds to the optimum application point of regulation R opt .
[0023] During operation, in a setting run or test run, as a first step a predicted first value for the application point of regulation, for example, R −5 is set. This value is preferably an empirical value. Inputting may occur by the inputting device 29 or by calling the data from a memory. Subsequently, the following steps are taken:
[0024] The sliver quality measured on-line for each setting of an application point of regulation is determined in each instance over a sliver length of 250-300 m.
[0025] The measurements for optimizing the application point of regulation are performed on a sliver length without coiler can exchange; this may occur, for example, while the draw frame is at a standstill between the individual application points of regulation R.
[0026] The determination of the on-line measured sliver quality is effected based on the following quality values:
[0027] Output sliver quality: CV 3cm , CV 10cm , CV 1m (determined, for example, by a sensor arrangement 25 at the draw frame outlet 4 which may be a SLIVER-FOCUS model manufactured by Trützschler GmbH & Co. KG).
[0028] Input sliver quality is described by CV in (this is performed at the sensor device 9 ).
[0029] From the above different quality values a quality-characterizing number QK is determined by the following formula:
QK=CV
3cm
+CV
10cm
+CV
1cm
−CV
in
[0030] With the above quality-characterizing number a sliver quality is sufficiently determined:
[0031] QK high→bad quality
[0032] QK low→good quality.
[0033] Based on the QK equation, the natural scattering of the individual values is reduced and outlier values are not evaluated beyond what they are worth. The formation of a mean value leads to more exact predictions, and the influence of the regulation for both long and short wavelengths is taken into consideration. Even the influence of the input quality (sliver 5 ) is taken into consideration in the computation.
[0034] The QK values which are computed from the real CV values obtained during tests are utilized for developing steps 4 , 5 , 6 , 7 and 8 described below.
[0035] The course of the quality curve above the application point of regulation R is always symmetrical to the minimum value of the curve (FIG. 3), that is, in case of an optimum application point of regulation R=0, the CV value deterioration at −4 is of the same extent as at +4. The functional relationship is described based on the symmetry by a polynomial of the second degree.
[0036] Preferably, the region between −5 and +5 is to be considered so that the quality differences are sufficiently substantial and, at the same time, the level of the application point of regulation remains realistic.
[0037] Reductions of three to four values for the application point of regulation R yield sufficient locations of reference (four pieces):
[0038] −5 −4 −3 −1 0 1 2 3 4 5
[0039] A polynomial of second degree (symmetrical course) is determined, with the aid of numerical solution process, from the four values for the application point of regulation R and the respective QK values.
[0040] Thereafter, by means of numeric processes the minimum of the curve is determined.
[0041] Such a minimum value is the optimum application point of regulation R in the then applicable machine setting and given fiber material (FIG. 4).
[0042] By visual observation (monitor screen 27 ) an automatic determination of the application point of regulation may be displayed for the operator in a reproducible manner (FIG. 4).
[0043] A number of different CV values of different sliver length portions are compared with one another and in addition to the output quality (sliver 5 ′″), the input quality too, is taken into consideration as an important quality characteristic. Further, the principal drafting point is calculated from the minimum of a polynomial of the second degree, that is, a symmetrical course. Based on an algorithm, several different CV values are combined to a quality-characterizing number QK. From the application points of regulation R and the corresponding quality-characterizing numbers a function is constructed by approximation. The minimum is calculated from the resulting function course. The determination is effected during pre-operational test run or setting run. The optimum application point of regulation R opt is taken over prior to beginning of the regular production by the control system 26 , 33 and a consistency inquiry is performed, possibly with error reports, and the result is reproducibly shown to the operator in a graphical representation. Four quality-characterizing numbers QK are obtained for determined application points of regulation R. These four quality-characterizing numbers are stored in a memory and based thereon a function curve is approximated. Only thereafter is the minimum of the function curve calculated. For each quality-number a few meters of sliver are delivered. The quality-characterizing magnitude (CV value) is determined between the delivery roll and the location of sliver deposition (output) as well as the measuring device 9 at the draw unit input 3 . The test run is performed during the charging of one coiler can. Between the four application points of regulation R (reference locations) the draw frame is stopped. The defined four application points of regulation R have different distances from one another.
[0044] The automatic optimization according to the invention of the application point of regulation has, among others, the following advantages:
[0045] Faster optimization of the application point of regulation;
[0046] Optimization is performed with economy of material;
[0047] No need to utilize laboratory equipment or Uster-testers;
[0048] CV values for the optimization are no longer distorted by effects such as coiler can deposition, climatic influences, and the like. In this manner, a better optimization result is achieved;
[0049] Realization of a “self-optimizing draw frame”;
[0050] Effective utilization of the machine control system (computer 26 );
[0051] By means of the automatic optimization the optimum application point of regulation may be found even if the data of the working memory and the data of the mechanical setting do not agree with one another; and
[0052] Knowledge transfer for performing at the manual optimization to the utilizer (operator) is dispensed with.
[0053] By virtue of the automatic determination of the application point of regulation (principal drafting point) not only the sliver uniformity but also, to the same extent, the CV values of the yarn quality may be improved. This was found in wool spinning products and PES/BW mixtures.
[0054] The invention was explained in connection with a regulated draw frame 1 . It is to be understood that it may find application in other machines which include a regulated draw unit 2 , such as a carding machine, a combing machine and the like.
[0055] It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims. | A method of directly determining setting values for an application point of regulation in a draw unit for drafting sliver includes the following steps: obtaining a plurality of measured values of a quality-characterizing magnitude, such as a CV value, of the drafted sliver; utilizing the measured values for formulating a function having a minimum constituting an optimal application point of regulation for controlling the draw unit; determining the optimal application point of regulation in a pre-operational run of the draw unit; obtaining measured values of at least two quality-characterizing magnitudes based on the drafted sliver; combining values of the quality-characterizing magnitudes at the sliver, which correspond to one another with respect to the application point of regulation, to a quality-characterizing number QK, and forming a function based on several numbers QK. The function has a minimum corresponding to an optimal application point of regulation R opt . | 3 |
RELATED APPLICATIONS
This application related to application Ser. No: 408,897, now U.S. Pat. No. 3,882,319, of the same inventors, entitled AUTOMATIC MELT LEVEL CONTROL FOR GROWTH OF SEMICONDUCTOR CRYSTALS and assigned to the same assignee as the subject invention.
BACKGROUND OF THE INVENTION
This invention relates to apparatus for growing semiconductor crystals, such as, for example, silicon or germmanium crystals, by the Czochralski method, more particularly to apparatus for automatically controlling the diameter of such a crystal at all diameter values from seed to final taper while the crystal is being pulled, and it is an object of the invention to provide improved apparatus of this nature.
The Czochralski method of crystal growing is well known and various schemes are available in the prior art for controlling the diameter of the crystal to a single value during the crystal pulling, or growing, process. While such diameter control schemes have been of the closed loop variety, it has not been known to use a stationary optical system which encompasses, optically, the whole range of crystal diameters from seed to final taper and to automatically control the diameter at all values including the final value according to predetermined settings of these parameters. Accordingly it is a further object of the invention to provide an improved system for crystal diameter control of the nature indicated.
It is a further object of the invention to provide an improved crystal diameter control of the character indicated which is simple in form, accurate in operation and achieves higher quality crystals, for example, crystals having better thermal stability and more consistent and repeatable crystal diameter.
SUMMARY OF THE INVENTION
In carrying out the invention in one form, there is provided in a system for automatically growing a crystal of controlled diameter from a seed, through neck-in, shoulder, body and final taper from a melt of material including a container for said melt, motor means for pulling a crystal from said melt; means for controlling said motor means; and means responsive to radiation existing at the liquid-solid interface of said crystal as it is being pulled for controlling said motor control means comprising, radiation sensitive means positioned to receive radiation from said liquid-solid interface throughout the total region from seed to final taper and having means associated with each of said regions responsive to the radiation from said each of said regions; programmed means for automatically selecting the radiation sensitive means associated with said each of said regions through the cycle of crystal growth from seed to final taper; and means for applying a signal from said selected radiation sensitive means to said motor control means which comprises lens means and a series of cells for receiving the radiation transmitted by said lens means.
In carrying out the invention according to a further form, there is provided in a system for automatically growing a crystal of controlled diameter from a seed, through neckin, shoulder, body and final taper from a melt of material including a container for said melt; motor means for pulling a crystal from said melt; means for controlling said motor means; and means responsive to radiation emanating from the liquid-solid interface of said crystal including the halo as said, crystal is being pulled for controlling said motor control means comprising, photosensitive means positioned to receive radiation from said liquid-solid interface throughout the total ragion from seed to final taper; said photosensitive means comprising a series of successively disposed photocells each one of which is arranged to receive radiant energy from a specific area of said liquid-solid interface including said halo between regions of seed and final taper, each photocell of said series being differentially connected to a second photocell spaced by at least one intervening photocell and defining a pair of photocells for developing an error signal whose magnitude varies linearly with changes in crystal diameter over a specified range of crystal diameters and having a null value at a particular value of crystal diameter, the signal from each successive pair of said photocells having a null value at a particular value of crystal diameter greater than the preceding crystal diameter by the same predetermined amount, the linear error signal region of each pair of said photocells extending to the linear error signal region of the next succeeding pair of photocells, programmed means for automatically selecting in sequence the successive pairs of said photocells throughout the cycle of crystal growth from seed to final taper; means for developing a crystal diameter related offset signal and means for combining said offset signal and error signal and supplying same to said motor control means for controlling said motor to pull said crystal to a predetermined diameter.
BRIEF DESCRIPTION OF THE DRAWINGS
For more complete understanding of the invention reference should be had to the drawings in which:
FIG. 1 is a somewhat diagrammatic representation, partially in section, of apparatus and system embodying the invention.
FIG. 2 is a top view of the apparatus shown in FIG. 1;
FIG. 3 is a diagrammatic view on a larger scale of a portion of the structure shown in FIG. 1;
FIG. 4 is a diagrammatic view similar to FIG. 3 but on a larger scale;
FIG. 4A is an elevational view representing a fully drawn crystal;
FIG. 5A is a diagrammatic view on an expanded liquid solid interface during crystal growth;
FIG. 5B is a graph illustrating the variation of radiation emanating from the expanded liquid-solid interface including the melt surface and the solid crystal;
FIG. 6 is a circuit and block diagram illustrating the operation of the invention;
FIG. 7 is a series of three curves useful in explaining the operation of the invention;
FIG. 8 is a series of graphs illustrating the response of the radiation detecting mechanism according to the invention;
FIG. 9 is a diagram illustrating one aspect of the operation of the sensing mechanism.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings there is shown apparatus 10 for pulling a crystal 11 from a melt 12. For example, the crystal may be silicon, germanium or other.
The apparatus 10 may comprise a more or less cylindrical chamber 13 of useful form and construction including a main body portion 14, a base 15 and a covering dome 16. The interior of the chamber 13 may be filled with any desired atmosphere. Interiorally of the chamber 13 there is a crucible 17 made of quartz, for example, supported on a shaft 18 which projects through the base 15 and is connected to a gear box 19. The gear box is associated with a drive motor 21 whereby the crucible 17, through the shaft 18, is rotated and the height of the crucible 17 may be raised or lowered so as to maintain the surface 22 of the melt constant throughout the crystal pulling operation as will be more fully explained.
Surrounding the crucible 17 is a heater 23 which conveniently may be electrical and of any well known form. Atop the dome 16 there is a shaft guide member 24 through which projects the shaft 25 for supporting the seed crystal 26. The shaft 25 is attached to a gear box 27 which is associated with a seed pull motor 28. The motor 28, through the gear box 27, acts to lift or pull the shaft 25 whereby the seed crystal 26 is pulled away from the surface 22 of melt 12 and, in so doing, forms a neckin portion 29, a shoulder 31, a crystal 11 at its final diameter 30, and ultimately the final taper 32 as the crucible becomes empty.
Also associated with the dome 16 is an observation window 33.
Directly opposite each other but displaced laterally from a diametrical line are two windows 34 and 35 through which infrared radiation is transmitted and received respectively. Infrared radiation is generated in the transmitter or source 36 which comprises two infrared sources 37 and 38 from which infrared radiation beams 39 and 41 are transmitted and aimed at a spot 42 on the surface 22 of the melt 12. Radiation beams 43 and 44 are reflected, respectively, from beams 39 and 41 and are transmitted through window 35 to the sensor, or receiver 45.
The transmitter 36, the receiver 45, the melt level control 46, the motor control 47 and their associated circuitry function to maintain the level 22 constant as is disclosed in the corresponding application Ser. No: 408,897 identified above.
For automatic crystal growth control there is provided a multi-cell photo detector 48 which views the total region of crystal growth through window 49 as visualize by the two rays 51 and 52 spanning the region from neckin 29 to the final diameter 30 of the crystal. The photo detector 48 supplies its signal over conductor 53 to a multiple element scanning eye control 54 which supplies a control signal over conductor 55 to the pull motor control 56 which in turn supplies the pull signal over conductor 57 to the pull motor 28. By appropriate signals as well subsequently become clear, the operation of the motor 28 as controlled by the pull motor control 56 functions to withdraw the crystal from the melt at the appropriate speed to give the precise shape desired by the present control of the apparatus. The diameter of the crystal is controlled by the error signal mechanism at each stage of the diameter. That is to say the diameter is controlled during the neckin portion 28, during the shoulder portion 31, during the final diameter 30 and during the final paper 32. In this manner uniform and high quality crystals can be consistently pulled.
These excellent results are achieved by having a stationary optical system as may be viewed from a consideration of FIGS. 1, 3 and 4 from which it appears that with a single lens system represented by the reference character 58, the image of the liquid-solid interface at the region of crystal growth from zero diameter (neckin) to final diameter 30 may be projected upon a multi-cell photo detector 62.
In one practical example, the multi-cell detector 62 comprised an array of closely adjacent 39 photo sensor cells each approximately 5 mils square. These dimensions are exemplary only. Thus 39 of the photocells form a small rectangle whose length is about two-tenths of an inch. Through the lens system exemplified by 58, the multi-cell photo detector 62 is projected to cover a crystal diameter from 0 to 3 1/2 inches in diameter without moving the sensing head in any way.
When a crystal is being pulled, as is well understood in the art, a seed crystal 26 of the desired crystallographic orientation is dipped into the melt 12 and is withdrawn at a predetermined rate. The first rate of withdrawal of the seed 26 is fairly high resulting in the neckin portion 29 which is of smaller diameter than the seed itself. After a predetermined length of neckin portion has been formed, the rate of withdrawal is decreased uniformly for a predetermined period thereby permitting the crystal to grow the shoulder 31 at an increasing diameter until the final crystal diameter 30 is arrived at. At each stage of withdrawal there is a liquid-solid interface or meniscus 63 as is shown in FIG. 5A. In this figure the meniscus is shown very much expanded, extending from the diameter of the crystal 11 to the surface 22 of the melt. The meniscus 63, of course, exists at each stage of crystal withdrawal as may be seen in FIG. 4.
In FIG. 5A the fragmentary portion of the crystal 11 is shown stippled for better representation. On the surface of the meniscus 63, somewhere between the crystal surface and the melt surface, there appears a halo 64 as is well understood in the art, the halo representing the region of maximum radiation as the melt material solidifies into the solid crystal. Radiation however eminates from the full extent of the meniscus and is detectable by the detector 62. In FIG. 5B there is shown a graph 65 representing the magnitude of the emitted radiation plotted against a horizontal distance representing, somewhat arbitrarily, the extend from the surface of the melt where the radiation is very low to some point of the final diameter of the crystal surface after solidification has occured and where the radiation again is very low. The horizontal scale of the graph in FIG. 5B is not an actual dimension along the surface of the melt but represents distances moved by a sensing device in measuring the radiation from one low value to another representing the full extent from the liquid melt to the solidified and relatively cool crystal surface. The peak 66 of the graph 65 appears more or less at the center of the halo 64 which has a width from one side to the other in practical cases observed of about one-eighth to one-tenth of an inch. The halo 64, it will be understood, is, of course, a ring of bright light surrounding the crystal. The radiation readings plotted as ordinates for graph 65 are shown as millivolts (MV) but any other unit could be used.
The location of the halo 64 on the surface of the meniscus 63 may be taken as representing the final diameter of the crystal 11. Thus, changes in the location of the halo 64, as the diameter of the crystal changes with the concomitant change in location of the peak 66 of the radiation graph 65, may be used to control the diameter of the crystal as it is being pulled at each stage of its withdrawal. As the halo moves, the location of the photocells of the sensor 62 being stationary, less peak radiation, of course, is received by any one cell as may be discerned by observing graph 65. The difference in radiation may be utilized to develop an error signal for controlling the crystal diameter, as is well understood. Accordingly to the subject invention two sensors are used at all points of crystal diameter and the radiation from the halo 64 and the meniscus on each side thereof are used to develop the error signals as shown in FIG. 8.
Referring to FIG. 9, the individual photocells (diodes) of the multi-cell photo detector 62 are shown side by side as individual units numbered respectively from 1a to 39a inclusive. Any number of cells, depending on the particular application needed, may of course be used. As already pointed out two photocells are used at each value of a crystal diameter to develop the error voltage at that diameter value. Consecutively numbered photocells of course lie adjacent each other as may be seen in FIGS. 4 and 9. According to one form of the invention, individual photocells separated by three numbers are used to develop the error signal for each diameter value. Thus the output voltages of cells 12a and 15a are combined to give graph 67, the output voltages of photocells 13a and 16a are combined to give graph 68 the outputs of photocells of 14a and 17a are combined to give the graph 69, and the outputs of photocells 15a and 18a are combined to give the graph 71 (FIG. 8). Correspondingly the outputs of other pairs of photocell diodes are combined to develop the error signals for controlling the crystal diameter, the pairs of photocells being separated by three numbers, until the final diameter is reached. The diameter is controlled by a feed back loop system.
At the final diameter, whatever it may be, the two photocells determining it may be for example 30a and 33a (FIG. 9).
The width of the halo 64 has been indicated to be about one-tenth to one-eighth of an inch and the individual photo-diode cells, according to the invention, covers an extent of about 0.05 of an inch at the surface of the halo. Thus each diode receives the radiation from about one third to one half of the halo radiation. With the photo-diodes so spaced and arranged the difference of the photo-diode outputs or voltages as occasioned by the radiation thereby result in the graphs 67, 68, 69 and 71 as described. Taking graph 68 (photocells 13a and 16a ), for example, it will be observed that the graph has a positive peak and a negative peak at 1.05 and 1.35 inches of the crystal diameter, passes through zero at 1.20 inches of crystal diameter and has a substantially linear portion extending from 1.15 and 1.25 inches of crystal diameter. Thus graph 68 can be used to to control the crystal diameter at 1.20 inches and can be used to control the diameter from between 1.15 to 1.25 inches, that is to say for a diametrical change of one-tenth of an inch. Similarly the graph 67 passes through zero at the crystal diameter of 1.10 inches, has a linear portion on each side thereof extending from 1.05 to 1.15 inches of crystal diameter and can be utilized to control the crystal diameter between 1.05 and 1.15 inches of crystal diameter, specifically at 1.10 inches; graph 69 passes through zero at 1.30 inches of crystal diameter, has a linear portion on each side thereof extending from 1.25 and 1.35 inches of crystal diameter and can be utilized to control the crystal diameter between 1.25 and 1.35 and specifically at 1.30 inches, if that is the final crystal diameter desired; and graph 71 passes through zero at a crystal diameter of 1.40 inches, has a linear portion on each side thereof extending from 1.35 inches to 1.45 inches of crystal diameter and can be used to control the final diameter of the crystal at 1.40 inches or to control the diameter in variations from 1.35 to 1.45 inches of crystal diameter.
The graphs 67, 68, 69 and 71 are plots of millivolts output representing the radiation voltages of two photodiodes against changes in the crystal diameter.
Observing the graphs of FIG. 8, it will be noted that by using the successive groups of photocells three numbers apart a continuous series of straight line portions, rising and falling, are available to control the crystal diameter from zero diameter to whatever value of diameter is desired.
Referring to FIGS. 6 and 7 there are shown a circuit diagram and graphs, respectively, illustrating diagrammatically additional structure and the functioning of the apparatus, according to the invention. It will be observed that the even numbered photocells 12a, 14a, 16a, 18a etc., are connected in one group and the odd numbered photo-cells 13a, 15a, 17a and 19a are connected together in a second group. The even numbered photocells 12a-18a are connected respectively through normally non-conducting field effect transistors (FETS) 72, 73, 74 and 75, respectively, to conductor 76 and through conductor 77 to one terminal of amplifier 78. Correspondingly, the odd numbered photocells 13a-19a are connected respectively through normally non-conducting field effect transistors (FETS) 79, 81, 82 and 83, respectively, to conductor 84 and through conductor 85 to one terminal of amplifier 86. One terminal of all the photocells, whether odd or even, are connected together to a conductor 87 going to a source of plus voltage for example 12 volts in one typical system. The amplifiers 78 and 86 may be of any well known form suitable for the purpose and as shown according to one form have the inputs from the doides connected to their negative terminals, the positive terminals being connected to the source of positive voltage. Each of the amplifiers include feed back resistors 88 and 89 as is well understood.
The output of amplifier 78 (even numbered diodes) is conducted through conductor 91 and resistor 92 to a terminal 93. The output of amplifier 86 (odd numbered diodes) is conducted through conductor 94 and resistor 95 to an inverting amplifier 96 of well known form and through resistor 97 and conductor 98 to terminal 93. Since the voltage from amplifier 86 was inverted by amplifier 96, the voltage at terminal 93 represents the difference between the voltages produced by the even numbered photocells and the odd numbered photocells. Thus the voltage at terminal 93 is the error voltage plotted as the outputs shown in FIG. 8. The voltage at terminal 93 is supplied to the positive terminal of which an offset voltage A may be supplied over conductor 101 from the shoulder wave from generator 102.
When the voltage at terminal 93 is zero that is to say when the voltages developed by the particular even and odd numbered photocells in circuit at the time are equal and there is no offset voltage A applied to amplifier 99 over conductor 101 the circuit will result in maintaining the diameter of the crystal at whatever value corresponds to the zero crossing voltage of the particular odd and even photocells. For example, if the photocells 12a and 15a were connected in circuit via appropriate energization of the FETS 72 and 81 the crystal diameter would be controlled at point 103 of graph 67 (FIG. 8). Under these conditions no signal would be supplied through electronic polarity reversing switch 104, the automatic diameter controller 105, the lift motor control 56 (FIGS. 1 & 3) and the seed pull motor 28 would thus remain running at whatever speed was required to maintain the crystal diameter at 1.10 inches corresponding to point 103 (FIG. 8). If, however, the crystal diameter should begin to increase the error voltage as shown by graph 67 would increase slightly (terminal 93) and the amplifier 99 would develop a voltage which would pass through the circuit components 104, 105 and 56 resulting in an increase in the speed of seed pull motor 28 with concomitant decrease in crystal diameter and a reduction of the error voltage to zero. Correspondingly, if the crystal diameter should decrease resulting in a slight decrease in the error voltage, the reverse procedure would take place. That is the decrease in error voltage would result in a decrease ultimately in the speed of the seed pull motor with a consequent increase in crystal diameter. Similar effects would take place if the crystal diameter were being controlled at a diameter of 1.20 inches (FIG. 8), the control error voltage coming from photocells 13a and 16a (graph 68) the control being about point 106 of graph 69, and diameter control of 1.40 inches would take place about point 108 of the graph 71 of photocells 15a and 18a.
The desired changes in diameter of a crystal while it is being grown to develop the neckin portion 29 and the shoulder 31 are developed by appropriate offset voltages A through the shoulder wave form generator 102, the digital logic circuitry 109 and the digital switch 110.
For an explanation of the remaining apparatus according to the invention, it will be assumed that a crystal is being pulled from a melt and that the operator has set the digital switch to some desired diameter for example 2.83 inches. The digital logic circuitry 109 receives the information as to the final diameter and already contains within it the desired information to give the dimensions of the neckin portion 29 and shoulder 31. The digital logic circuitry 109 supplies an appropriate signal over conductor 111 to the sensor head logic control circuitry 112 which supplies turn on voltages over conductors 113, 114, 115, 116, 117, 118, 119, 121 etc., of the FETS 72, 73, 74, 75, 79, 81, 82, and 83 respectively. The sensor head logic and control circuit 112, of course, has sufficient lines to supply turn on and turn off signals to all of the photocells in addition to the ones immediately referred to.
It will be further assumed that at the particular instant the crystal diameter is being controlled at 1.10 inches (point 103 of graph 67). The sensor head logic and control circuit 112 under the influence of the digital logic circuitry 109 has turned on FETS 72 and 81 by voltages over conductors 113 and 118. The output voltages from photocells 12a and 15a add to zero error voltage at terminal 93. At this point the offset voltage A is introduced into the amplifier 99 from shoulder wave form generator 102 over conductor 101. The offset voltage A at this point has a negative going portion 122 (FIG. 7). The voltage at the output of amplifier 99, conductor 100, goes negative, destroying the balance in the motor control circuitry, and causes the seed pull motor to run slower, thereby increasing the crystal diameter. This in turn causes the error voltage developed by diodes 12a and 15a to increase positively to bring the error voltage at terminal 93 to a value equalling that of offset 122 so as to bring the voltage at conductor 100 back to zero. This continues until the crystal diameter has increased to 1.15 inches. Here, under the present crystal growth program, the shoulder wave form generator 102 sends a pulse C (FIG. 7) over conductor 123 to the digital logic circuitry 109. This in turn sends a signal over conductor 111 to the sensor head logic and control circuitry 112 causing it to select the next pair of diodes 13a and 16a by sending a turn on signal over conductors 117 and 115 while at the same time sending a turn off signal to FETS 72 and 81 over conductors 113 and 118.
The polarity of the error signal developed at terminal 93 in the case of diodes 13a and 16a is reversed with respect to the polarity of the error voltage at terminal 93 for the case of diodes 12a and 15a. Thus, during the course of crystal shoulder growth, the sign of the error signal with respect to the crystal diameter error alternates depending upon whether the lower numbered photo-diode element is numbered odd or even. Hence from control loop considerations, an electrical polarity reversing switch is needed and is represented in the circuit of FIG. 6 by the reference character 104.
At the time that the shoulder wave form generator 102 sends a signal pulse 124 to change photo-diodes from 12a and 15a to 13a and 16a, a signal pulse 125 (curve B of FIG. 7) is sent over conductor 126 to the reversing switch 104.
When the pair of diodes 13a and 16a has been selected and is connected into the circuit, the immediate indication at terminal 93 (input to amplifier 9) is that the crystal is undersized by 0.05 inches. However the voltage wave 122 at the point 127 applied over conductor 101 to amplifier 99 just cancels this error voltage. The triangular, or saw tooth, voltage wave, that is, the offset voltage over conductor 101 moves toward the zero axis and beyond along the graph leg 128 and the crystal must therefore keep increasing in diameter in order for the error voltage input to amplifier 99 to remain nulled. It is noted that the error voltage curve 68 for the photo-diodes 13a and 16a is just like the error voltage curve for diodes 12a and 15a (67) except that it is displaced along the diameter axis by one-tenth of an inch and is inverted. The slowly varying voltage wave 128 continues applying an offset voltage to input 101 of amplifier 99 until the crystal reaches a diameter of 1.25 inches.
At this point, another pulse 129 is emitted from the shoulder wave form generator 102 to the digital logic circuitry 109 which tells the sensor head logic and control circuit 112 to turn off diodes 13a and 16a and to turn on diodes 14a and 17a. The later is accomplished by turning on FETS 73 and 82 by appropriate signals over conductors 114 and 119. Also at this point, the offset voltage generated by the shoulder wave form generator 102 is that shown by the triangular wave leg 132 beginning at point 129. Also the shoulder wave form generator 102 generates the negative going signal 133 which passes over conductor 126 to establish the correct polarity of the signal going to the lift motor control. Under the influence of the offset voltage 132 the crystal keeps increasing in diameter for the error voltage at terminal 93 to have the proper magnitude at its input to the amplifier 99 in order to keep the total input to this amplifier nulled. It is noted that the error curve for photo-diodes 14a and 17a (69) is just like the preceding error graphs 67 and 68 except that it is displaced along the diameter axis by an additional one-tenth of an inch and is inverted with respect to the error graph 68.
The continued application of the offset voltage 132 causes the diameter of the crystal to increase to 1.35 inches at point 134 on the error voltage graph. At this point a pulse 135 is emitted from the shoulder wave form generator 102 and passes to the digital logic circuitry 109 which in turn commands the sensor head logic and control circuit 112 to turn off the FETS 73 and 82 to disconnect, so to speak, the photo-diodes 14a and 17a. At the same time it causes the sensor head logic and control circuitry 112 to send a turn on signal to the FETS 81 and 75 to connect photo-diodes 15a and 18a into the circuit. The offset voltage becomes positive going as shown by the graph portion 136 and the crystal diameter continues to increase under this influence until it reaches a diameter of 1.45 inches. The shoulder wave form generator 102 at the point 134 of the offset voltage curve sends a signal 137 to the polarity reversing switch 104 for purposes already described. The crystal growth under the influence of photo-diodes 15a and 18a is shown by the graph 71 for that portion thereof extending the crystal diameter of 1.35 to 1.45 inches.
The procedure described for the pairs of photo-diodes 12a-15a, 13a-17a, and 15a-18a continues until the counter in the digital circuitry contains the number of corresponding to the present diameter of 2.83 inches, for example, or any other. At this point the shoulder wave form generator 102 is shut off and whatever pair of photo-diode elements corresponding to the desired crystal diameter is now used for the remainder of the crystal growth at the constant diameter. The conical shoulder at this point is rounded over and the crystal continues to grow cylindrically from this point on.
As has been described, the FETS including 72-83 are driven from the digital logic circuits and only one odd photodiode element and one even photo-diode element are on at any one time. Thus pairs of photo sensor diodes are used to cover each 0.1 inches of diameter. Within each of these increments electrically offsetting of the control point is used to achieve a diameter setting capability accurate to 0.01 inches. After the crystal is drawn at its final diameter and is described the end portion 32, or final taper is formed in the same manner.
The circuit components shown to the left of the dotted line 138 in FIG. 6 may conveniently be disposed in multi-cell photo detector unit 48 shown in FIGS. 1 and 3. The crystal growth programmer 139 of FIG. 3 comprises the circuit components 102, 109 and 110 of FIG. 6 and other adjustments needed for neck diameter, neck length, shoulder angle and final diameter as shown in FIG. 3. | Apparatus for automatically controlling, by stationary optical means, the diameter of a crystal from seed to final taper in a Czochralski crystal pulling method is disclosed. The diameter control has a feed back loop including diameter sensing means which controls a motor for moving the pulled crystal up faster or slower. The diameter, at any value, is sensed by two closely adjacent photocells receiving radiation from spaced points on the solid-liquid interface and a voltage value corresponding to that diameter is developed.
When a constant diameter is being maintained and the diameter increases, the magnitudes of the sensed radiation change and a difference signal voltage in one direction is generated causing the crystal pull rate to increase. When the diameter decreases the magnitudes of the sensed radiation change in the reverse and a difference signal voltage in the opposite direction is generated causing crystal pull rate to decrease.
For causing the crystal to grow in diameter as desired an offset voltage according to a predetermined program is balanced against the photocell voltage error voltage of one pair of photocells and the resultant difference signal is used to control the pull speed so as to change the diameter accordingly. When the diameter has changed, for example, increased to a point where the liquid-solid interface has changed location sufficiently, the next set of photocells takes over to develop an error voltage. A further diameter related offset voltage is developed and balanced against the error voltage and the crystal is forced to continue to increase in diameter accordingly. The process continues until final diameter is reached. | 6 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a system for controlling and conveying air flows through the engine compartment of a motor vehicle, specifically for a motor vehicle of the type referred to in the preamble of the annexed Claim 1 .
SUMMARY OF THE INVENTION
[0002] The technical problem that the present invention intends to solve is that of managing the flow of air that traverses the engine compartment of a motor vehicle in order to improve the aerodynamic characteristics of the motor vehicle. In traditional automobiles, the air that enters the engine compartment from the front part of the motor vehicle is in no way controlled or guided towards the outlet openings and is hence free to lap the various parts of the engine unit and then come out on the outside. Up to the present day, advanced systems tending to convey or guide towards the outlet the air that enters the engine compartment in an optimal way in order to reduce the aerodynamic resistance of the motor vehicle have not been devised.
[0003] The object of the present invention is consequently to propose a system that is able to control and convey the flow of air that traverses the engine compartment of a motor vehicle in order to improve in a non-negligible way the aerodynamic characteristics of the vehicle itself.
[0004] Another object of the invention consists in achieving the purposes referred to above through the use of relatively simple and low-cost means.
[0005] According to the main characteristic of the invention, which forms the subject of the characterizing part of the annexed Claim 1 , a structure is provided for conveying the air that has traversed the radiator and the fan set behind it, in the form of a tubular duct, with a widened cylindrical mouth that surrounds the aforesaid fan completely, behind the radiator and that is prolonged downwards in a horizontally widened and vertically flattened portion in a position corresponding to the bottom area of the fan, up to an outflow mouth set underneath the floor panel, on the outside of the body, in order to reduce the aerodynamic resistance of the motor vehicle preventing the passage of a considerable flow of air longitudinally through the engine compartment and conveying the flow at outlet from the radiator underneath the floor panel of the motor vehicle and longitudinally along it.
[0006] Thanks to the aforesaid characteristics, the invention makes it possible to prevent the majority of the flow of air that enters the engine compartment from proceeding through it after traversing the radiator. Instead, the flow at outlet behind the radiator is immediately conveyed downwards and then longitudinally up to the outflow mouth underneath the floor panel so as to have a minimum impact on the aerodynamic resistance of the motor vehicle.
[0007] In the preferred embodiment, the aforesaid conveyor has a closed wall substantially facing the fan, behind it, for connection of the mouth of the conveyor to the flattened bottom portion.
[0008] In theory, the deviation of the main flow of air underneath the engine compartment could present the drawback of not enabling an adequate cooling of some parts of the engine unit, such as the exhaust duct of the engine, or of some electronic components associated to the engine. In order to prevent said drawback, according to a preferred characteristic of the invention, the aforesaid conveyor is provided, in a position corresponding to the aforesaid front wall, with one or more openings controlled by orientable fins to enable the passage of a reduced and controlled amount of air through the engine compartment. Once again in the case of the preferred embodiment, the aforesaid fins form part of a venetian-blind structure, controlled by actuator means, preferably with electrical actuation and controlled by electronic control means on the basis of the signals issued by sensor means for detecting the speed of the motor vehicle and sensor means for detecting a temperature indicating the operating conditions of the engine, for example the temperature of the engine coolant, according to a programmed logic, in order to enable adequate cooling of the components of the engine unit and of the electronic components associated thereto. There may, for example, be envisaged automatic opening of said fins below a pre-set speed of the motor vehicle and/or above a pre-set value of the aforesaid temperature indicating the operating conditions of the engine.
[0009] According to a further preferred characteristic, the system according to the invention also envisages, according to a solution in itself known, one or more openings set on the front part of the motor vehicle, alongside the fan, and controlled by passive fins, i.e., ones designed to open as a result of the relative wind when the motor vehicle is travelling above a predetermined speed in order to enable a flow at input to the engine compartment, in parallel to the flow that traverses the radiator at high speeds of the motor vehicle, for example in order to enable adequate cooling of some specific components of the motor vehicle. Said passive fins are recalled towards the closed condition, for example by their own weight and/or in so far as they are equipped with elastic-return means.
[0010] The present invention also enables the advantage of achieving acoustic containment and withholding of the heat generated by the engine unit. Said latter aspect is particularly important for the purposes of shortening the duration of the step of engine warm-up after starting, particularly after a cold starting, with consequent saving in terms of fuel consumption.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Further characteristics and advantages of the invention will emerge from the ensuing description with reference to the annexed drawings, which are provided purely by way of non-limiting example and in which:
[0012] FIG. 1 is a schematic view in longitudinal section of the front part of a motor vehicle equipped with the system according to the invention;
[0013] FIG. 2 is a schematic view from beneath of the motor vehicle of FIG. 1 ;
[0014] FIGS. 3 and 4 are schematic views, which illustrate the active and passive fins, with which the conveyor forming part of the system according to the invention is provided; and
[0015] FIGS. 5 , 6 and 7 are details at an enlarged scale of the system for controlling the active fins, with which the conveyor forming part of the system according to the invention is provided.
DETAILED DESCRIPTION OF THE INVENTION
[0016] In the drawings, the reference number 1 designates as a whole an automobile of any known type, comprising a body including a floor panel 2 (see FIG. 2 ) and defining, in its front part, an engine compartment 3 in which an engine unit 4 is set, from which an exhaust pipe 5 extends, which, in the example illustrated, is set underneath the floor panel in a position corresponding to a tunnel-shaped part thereof. Provided in the front part of the motor vehicle is a grill 6 for access of the air to a radiator 7 inserted in the circuit for the coolant of the engine 4 . Provided at the rear of the radiator 7 is a fan 8 controlled in a way in itself known by motor means (not illustrated) that set it in rotation to activate or increase the flow of air through the radiator 7 .
[0017] In the system according to the invention, the air coming from the front grill 6 that traverses the radiator 7 and the fan 8 does not proceed further through the engine compartment 3 in so far as it is conveyed directly downwards and underneath the floor panel of the motor vehicle by a conveyor structure 9 .
[0018] As may be seen in FIG. 3 , the conveyor structure 9 is in the form of duct with a widened cylindrical mouth 10 surrounding the fan 8 . Starting from said mouth 10 , the conveyor 9 is prolonged downwards in a flattened portion 11 that comes out underneath the floor panel 2 , through a slot 12 (see FIG. 2 ) provided in a bottom shield 13 set underneath the floor panel 2 and underneath the engine unit.
[0019] As may be seen in FIG. 3 , the conveyor 9 has a front wall 14 , facing the rear of the fan 8 , via which the edge of the cylindrical mouth 10 is radiused with the bottom flattened portion 11 that extends longitudinally backwards starting from the bottom area of the fan.
[0020] As illustrated above, as a result of the arrangement of the conveyor 9 , the main flow that traverses the radiator 7 and the fan 8 does not proceed further through the engine compartment, but rather is conveyed immediately underneath the floor panel. Studies and tests conducted by the present applicant show that, as a result of said arrangement, the aerodynamic characteristics of the motor vehicle are considerably improved.
[0021] At the same time, in order to enable an adequate cooling of the engine unit and of the electronic components associated thereto, particularly at low speeds of the motor vehicle, on the front wall 14 there are provided a number of openings controlled by active fins 16 , which form part of a venetian-blind structure (see FIGS. 3 and 5 - 7 ) controlled by an electrically actuated actuator 17 , for example, an electromagnet or a shape-memory actuator, or else an electric motor or any other type of known device. According to a typical characteristic of the venetian-blind structures, a bar 18 for connection of the fins ensures the synchronized movement of the latter, as illustrated in FIG. 11 . Of course, any other arrangement and any other type of control for the active fins 16 may be used.
[0022] The actuator 17 is controlled by an electronic control unit (not illustrated), according to a programmed logic, as a function of a signal indicating the speed of the motor vehicle (supplied, for example, by a speed sensor or else generated by the electronic control unit on the basis of data regarding the operating conditions of the engine and of the transmission) and/or as a function of the signal at output from a sensor of a temperature indicating the running conditions of the engine, for example the temperature of the coolant, in order to control opening of the fins below a predetermined speed and/or above a predetermined value of the aforesaid temperature.
[0023] According to a further characteristic ( FIG. 4 ), in accordance with a solution in itself known, provided alongside the conveyor 9 are openings controlled by passive fins 19 that open automatically as a result of the relative wind above a predetermined speed to enable adequate cooling of some components of the engine unit and/or of the motor vehicle (for example the brakes) at high speeds. Said passive fins are recalled towards the closed condition, for example by their own weight and/or in so far as they are equipped with elastic-return means. In the case of the example illustrated, the fins 19 are provided in a closed wall 26 that covers the radiator at the rear on the outside of the conveyor structure 9 . They could, however, be provided in any other area of the front wall of the motor vehicle.
[0024] Some of the electronic components associated to the engine unit that call for particular attention as regards adequate cooling thereof may obviously be provided within the engine compartment in positions that are suitable for receiving an adequate flow of air following upon opening of the active fins 16 and passive fins 19 .
[0025] As emerges clearly from the foregoing description, the system according to the invention enables, with relatively simple and low-cost means, considerable advantages both from the standpoint of the reduction of the aerodynamic resistance of the motor vehicle, and hence of the reduction of the fuel consumption, and from the standpoint of the improvement of the acoustic and thermal insulation of the engine compartment, once again with consequent advantages in terms of reduction of consumption, in the engine warm-up stages.
[0026] Of course, without prejudice to the principle of the invention, the details of construction and the embodiments may vary widely with respect to what is described and illustrated herein purely by way of example, without thereby departing from the scope of the present invention. | A motor vehicle is provided with a conveyor structure that conveys the entire flow of air that traverses the radiator downwards and then longitudinally underneath the floor panel of the motor vehicle, preventing said flow from traversing the engine compartment and obtaining a consequent reduction in the aerodynamic resistance of the motor vehicle. Associated to the aforesaid conveyor structure are active and passive fins for enabling an adequate cooling of the components of the engine unit or electronic components associated thereto during given operating conditions. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates in general to a saddle rack and, more particularly, to a saddle rack which reduces undesirable distortion of the saddle and maintains the saddle off the ground.
2. Description of the Prior Art
Modern western saddles are often constructed of leather formed around a sturdy frame, often called a “tree.” When the leather becomes soaked with sweat it may become deformed if the saddle is not stored and dried in a manner designed to maintain its shape. If the leather dries in a deformed manner, the saddle may have an irregular surface which can cause pressure points on the back of a horse or other animal upon which the saddle is secured.
It is known in the art to store saddles on the ground or over stall dividers, sawhorses, fences or the like. One drawback associated with prior art saddle storage means is the tendency of such storage means to undesirably deform the saddle. During use, a saddle may become moist with sweat from the animal upon which it is placed. The sweat may cause the saddle to become more malleable. When placed over a fence or on the ground, the weight of the saddle combined with the moisture causes the saddle to deform. As the saddle dries, the saddle may stiffen in the deformed shape. It would, therefore, be desirable to position the saddle upon a saddle rack which maintained the desired configuration of the saddle.
While it is known in the art to provide decorative saddle racks, such racks are expensive, heavy and often do not allow adequate ventilation to allow the perspiration to escape from the saddle. Accordingly, when placed on such a decorative rack, the perspiration may cause mold which may damage either the decorative rack or the saddle. Another drawback associated with such prior art racks is that the weight, cost and inability of the racks to weather the elements often prevents such decorative saddle racks from being used in a barn or other work environment.
While it is known in the art to provide metal saddle racks, such as that described in U.S. Pat. No. 4,541,535, and while such saddle racks allow for a substantial amount of venting of the saddle during storage, such racks support the saddles along an undesirably small number of locations. Some saddles are often provided with a fleece lining under the tree which serves as padding to reduce discomfort on the back of the horse. Placing the saddle on a device, such as a wire rack, which only supports the saddle in a limited number of places may cause the fleece to rub off of the saddle. Loss of fleece may cause rubbing and abrasion on the animal at the places where the fleece is missing. Although such prior art saddle racks are often better than stall dividers or fences, the saddle racks still allow for deformation of the saddle when placed thereon. It would, therefore, be desirable to provide a saddle rack which supported a saddle over a large area.
Accordingly, it would be desirable to provide a low cost, lightweight saddle rack which provides for full support of a saddle during storage while allowing for adequate ventilation as the saddle dries. It would also be desirable to provide a saddle rack which is adjustable and movable from one location to another. The difficulties encountered in the prior art discussed above are substantially eliminated by the present invention.
SUMMARY OF THE INVENTION
In an advantage provided by this invention, a saddle rack is provided which is of a low cost manufacture.
Advantageously, the present invention provides a saddle rack which is adjustable.
Advantageously, the present invention provides a saddle rack which reduces deformation of a saddle during storage.
Advantageously, the present invention provides a saddle rack which is removable.
Advantageously, the present invention provides a saddle rack which is easy to maintain.
Advantageously, the present invention provides a saddle rack which provides for adequate venting during storage of a saddle.
In an advantage provided by this invention, a saddle rack is provided having a resilient frame and means for biasing the frame toward an arcuate shape. Means are also provided for securing the frame to a wall. In the preferred embodiment, a mount is secured to the wall and a linkage is provided releasably securing the curved frame to the mount. The frame is preferably provided with a plurality of vents to allow the saddle to dry during storage.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will now be described, by way of example, with reference to the accompanying drawings in which:
FIG. 1 illustrates a side perspective view of the saddle rack of the present invention coupled to a wall;
FIG. 2 illustrates a side elevation in partial cutaway of a saddle used in association with the saddle rack of the present invention.
FIG. 3 illustrates a bottom plan view in partial cutaway of the saddle of FIG. 7 .
FIG. 4 illustrates a front elevation of the frame biased into an arcuate configuration;
FIG. 5 illustrates a top plan view of the frame prior to biasing;
FIG. 6 illustrates a side elevation of the linkage connecting the frame to the wall bracket; and
FIG. 7 illustrates a front perspective view of an alternative embodiment of the present invention mounting the frame to a saddle rack stand.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention relates to a saddle rack shown generally as ( 10 ) in FIG. 1 . The saddle rack includes a resilient frame ( 12 ) coupled to a wall ( 14 ). The wall ( 14 ) may be part of a barn ( 16 ), trailer (not shown), or any other desired location for storage of a saddle ( 18 ). ( FIGS. 1-2 ).
As shown in FIG. 1 , while the frame ( 12 ) may be constructed of any desired material, in the preferred embodiment the frame ( 12 ) is constructed of thin, bendable aluminum, having a thickness of between 0.05 and 0.5 inches, more preferably between 0.08 and 0.2 inches, and most preferably 0.12 inches in thickness. In the preferred embodiment, the frame ( 12 ) is constructed of bendable aluminum to prevent the frame ( 12 ) from rusting, and to allow the frame ( 12 ) to be lightweight and adjustable. The saddle rack ( 10 ) is preferably less than fifteen kilograms, more preferably less than ten kilograms, and most preferably, less than five kilograms.
As shown in FIG. 2 , the saddle ( 18 ) is constructed of a frame or tree ( 20 ) around which is provided a layer of leather ( 22 ). The tree ( 20 ) preferably defines a cantle ( 24 ) and a pommel ( 26 ) upon which is provided a horn ( 28 ). The portion of the tree ( 20 ) between the cantle ( 24 ) and pommel ( 26 ) defines the seat ( 30 ). Provided underneath the tree ( 20 ) are layered fabrics which may be constructed of leather, cotton or the like which include the rear jockey ( 32 ) and skirt ( 34 ). Depending from the tree ( 20 ) are fenders ( 36 ), preferably constructed of leather and secured to a pair of stirrups ( 38 ). A cinch ( 40 ) is secured to the tree ( 20 ).
As shown in FIGS. 2-3 , the underside of the tree ( 20 ) is provided with padding ( 42 ), such as fleece, to prevent injury to the horse. The underside of the saddle ( 18 ) is also provided with a sweat flap ( 44 ) to protect the fenders ( 36 ) from sweat, dirt and other debris. The tree ( 20 ) and padding ( 42 ) are preferably constructed and configured to evenly distribute the weight of the saddle ( 18 ) and a rider (not shown) on an animal (not shown). If the saddle ( 18 ) is ridden for a sufficient amount of time to cause sweat from the animal to be deposited upon the padding ( 42 ), and the saddle ( 18 ) is not properly stored, the sweat can cause the leather ( 46 ) and padding ( 42 ) on the underside of the saddle ( 18 ) to deform. This deformation can prevent even distribution of weight on the animal and can cause pressure points and injury to the animal in some cases. Additionally, pressure points can cause undue wear and premature damage to the saddle ( 18 ).
While it is known in the art to provide the saddle ( 18 ) on wire racks or over a fence, such storage means do not properly maintain the correct configuration of the saddle ( 18 ) as the saddle ( 18 ) and the leather ( 22 ) and ( 46 ) thereon dries and contracts. Additionally, such storage mechanisms can cause imprints of the wire rack or fence to be left on the saddle ( 18 ), thereby causing worn padding ( 42 ) and pressure points, leading to injury to the animal and undue wear of the saddle ( 18 ).
As shown in FIG. 1 , the saddle rack ( 10 ) is provided with a curvature ( 48 ) substantially equal to the curvature of the animal upon which the saddle ( 18 ) is to be provided. As shown in FIGS. 1 and 4 , the frame ( 12 ) is provided with a pair of holes ( 50 ) ( 50 ) coupled to a pair of chains ( 52 ) and ( 54 ). The chains ( 52 ) and ( 54 ), in turn, are coupled to one another by a turnbuckle ( 56 ), such as those well known in the art. The chains ( 52 ) and ( 54 ), and turnbuckle ( 56 ), can be adjusted to change the curvature ( 48 ) of the frame ( 12 ) as desired to accommodate saddles ( 18 ) of various configurations.
As shown in FIG. 5 , the frame ( 12 ) is preferably cut from a flat sheet of resilient aluminum to form a plurality of vents ( 58 ), a handle ( 60 ), a retainer slot ( 62 ) and a pair of shoulders ( 64 ) and ( 66 ). The vents ( 58 ) may be of any desired number, configuration or orientation, and may, if desired, be provided in open communication with one another. The vents ( 58 ) are preferably designed to adequately ventilate the saddle ( 18 ) during storage to allow sweat and other moisture to evaporate therefrom while maintaining the configuration of the saddle ( 18 ). In the preferred embodiment, the retaining slot ( 62 ) is provided approximately one inch from the rear edge ( 68 ) of the frame ( 12 ), centered in relation thereto and provided with a width of one inch and a length of one-half inch. The dimensions of the retaining slot ( 62 ) may be adjusted as desired but is preferably located on the rearward half of the frame.
The shoulders ( 64 ) and ( 66 ) in the preferred embodiment are 2.0 inches in width and approximately 1.62 inches in length. The shoulders ( 64 ) and ( 66 ) may, of course, be of any suitable dimensions but preferably do not extend over the area ( 70 ) located directly rearward of the retainer slot ( 62 ).
As shown in FIGS. 4 and 6 , a retainer ( 72 ) is provided to secure the saddle rack ( 10 ) onto the wall ( 14 ). In the preferred embodiment, the retainer ( 72 ) is constructed of a 0.75 inch wide, 0.125 inch thick, strip of steel ( FIGS. 4-6 ), bent to be provided with a hook ( 74 ) sufficient to retain the frame ( 12 ) through the retainer slot ( 62 ). The retainer ( 72 ) forms a curve ( 76 ) at the base of the hook ( 74 ) to receive the ring ( 78 ) of a bracket assembly ( 80 ). The bracket assembly ( 80 ) includes a plate ( 82 ) bolted or otherwise secured to the wall ( 14 ) and a sleeve ( 84 ) secured thereto. The trapezoidal ring ( 78 ) is provided within the sleeve ( 84 ) to create a hinged coupling of the ring ( 78 ) to the plate ( 82 ). As shown in FIG. 5 , the ring ( 78 ) is received in the curve ( 76 ) of the retainer ( 72 ). Approximately an inch down from the curve ( 76 ) is another curve ( 86 ) which extends the retainer ( 72 ) back toward the wall ( 14 ). At the wall ( 14 ), approximately 1.5 inches away, the retainer ( 72 ) is provided with a downward curve ( 88 ) to abut the retainer ( 72 ) against the wall ( 14 ).
When it is desired to utilize the saddle rack ( 10 ) of the present invention, the bracket assembly ( 80 ) is positioned at a desired location on the wall ( 14 ), or at any other desired location. A turnbuckle ( 56 ) is then adjusted to create the desired curvature ( 48 ) for the saddle ( 18 ). The retainer ( 72 ) is provided through the ring ( 78 ) so that the ring ( 78 ) rests at the curve ( 76 ) of the retainer ( 72 ). The saddle rack ( 10 ) is then positioned over the retainer ( 72 ) so that the hook ( 74 ) of the retainer ( 72 ) is provided through the retainer slot ( 62 ). The saddle rack ( 10 ) may have to be tilted slightly upward to allow the hook ( 74 ) to engage the frame ( 12 ).
The shoulders ( 64 ) maintain the saddle rack ( 10 ) at a predetermined distance from the wall ( 14 ). Once the saddle rack ( 10 ) has been mounted, the saddle ( 18 ) may be placed thereon. The orientation of the frame ( 12 ) and vents ( 58 ) allow the saddle to properly dry, while maintaining its shape and preventing distortion. After storage is completed, the saddle ( 18 ) may be removed from the saddle rack ( 10 ) and the saddle rack ( 10 ) gripped by the handle to be removed from the retainer ( 72 ). Removal allows the space formerly occupied by the saddle rack ( 10 ) to be better utilized when the saddle rack ( 10 ) is not in use.
An alternative embodiment of the present invention is shown generally as ( 90 ) in FIG. 6 . As shown in FIG. 6 , the alternative embodiment ( 90 ) includes a rack ( 92 ). The rack ( 92 ) may be of any desired configuration, but is desirably designed to fold up and extend to support the saddle rack ( 10 ) when a wall or post is not available to locate the bracket assembly ( 80 ). As shown in FIG. 6 , the rack ( 92 ) is of a standard folding configuration, with a first generally U-shaped assembly ( 94 ) pivotally coupled to a second generally U-shaped assembly ( 96 ) at pivot points ( 98 ) and ( 100 ), coupled by a spacer bar ( 102 ). The top bars ( 104 ) and ( 106 ) are preferably rounded to accommodate the curvature ( 48 ) of the saddle rack ( 10 ). In the preferred embodiment, the U-shaped assemblies ( 94 ) and ( 96 ) are coupled to one another by a pair of cords ( 108 ) and ( 110 ) to prevent the rack ( 92 ) from opening too wide and preventing the rack ( 92 ) from collapsing with the weight of the saddle rack ( 10 ) placed thereon. The rack ( 92 ) may be constructed of any suitable material and of any suitable dimensions, but is preferably foldable for ease of storage and transport.
Although the invention has been described with respect to a preferred embodiment thereof, it is to be understood that it is not to be so limited since changes and modifications can be made therein which are within the full, intended scope of this invention as defined by the appended claims. | A saddle rack is provided with a resilient frame and means for biasing the frame to a desired arcuate shape. The saddle rack includes a retainer that allows the saddle rack to be coupled to a wall bracket for use and easily removed when not in use. The saddle rack includes a curved shape and venting to allow a saddle to properly dry without becoming damaged or disfigured during storage. | 1 |
FIELD OF THE INVENTION
This invention relates to the plumbing industry. More particularly, the invention provides an easily-used and portable machine that allows a plumber to produce accurate, uniform bends in pipes with varied diameters.
DESCRIPTION OF THE PRIOR ART
A pipe bending or forming machine allows a worker to form straight sections of pipe into the required curves for a particular construction. Such a machine is disclosed in British Pat. No. 1,163,407 wherein a section of pipe is forced against a semi-circular forming section by a press. This invention uses a removable setting piece to determine the spacing between the press and a pipe guide and is awkward to use if pipes of different thickness are to be bent.
SUMMARY OF THE INVENTION
The present invention overcomes the above limitations by providing a pipe bending machine with an easily adjustable bending section to facilitate the bending of pipes having different thicknesses. A bending mandrel that is secured against a steady, yet portable and easily transportable, base is provided. A rotation yoke is rotatably secured to the mandrel and provides pressuring movement around said mandrel to force the pipe into a desired bend. A curvature guide attached to the mandrel allows repetitive bends to be made.
OBJECTS OF THE INVENTION
It is therefore an object of the present invention to provide a machine that will easily bend sections of pipe.
It is a further object of the present invention to provide a machine that will easily reproduce the same bend in a multitude of sections of pipe.
It is a still further object of the present invention to provide a machine that will bend sections of pipe without crimping the bent sections.
These and other objects and advantages of the present invention will be readily apparent to those skilled in the art by reading the following brief descriptions of the drawings, detailed description of the preferred embodiment and the appended claims.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a perspective view of the instant invention showing hidden lines of the yoke housing and a section of pipe and the spring mechanism in phantom;
FIG. 2 is a side view of the instant invention showing a section of pipe (in phantom) and a rotation of 45° (as shown by the arrows) of the yoke housing (also in phantom) to put a bend in the section of pipe (also in phantom);
FIG. 3 is a front elevation view of the instant invention;
FIG. 4 is a fragmentary plan view of the instant invention;
FIG. 5 is an enlarged fragmentary front elevation sectional view taken along lines V--V of FIG. 4;
FIG. 6 is a fragmentary side view of a schematic showing operation of the curvature guide 170 and rotation yoke 100;
FIG. 7 is a side view of one size of mandrel 60 showing the bottom of groove 63 in phantom;
FIG. 8 is a side view of one form of semi-sleeve 180 showing the bottoms of grooves 182a, 182b in phantom; and
FIG. 9 is a sectional view along IX--IX of FIG. 8.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As seen in FIG. 1, the portable pipe bending machine 10 has a mounting bracket 20 with two pivotable and adjustable bracing supports 31, 32 extending therefrom. Mounting bracket 20 is comprised of an end wall and a pair of oppositely spaced parallel side walls 21, 22 extending therefrom. Bracing supports 31, 32 provide a solid and steady working platform from which the portable pipe bending machine may be used. Upper support 32a is fixedly fastened at its proximal end to right side wall 21 as is known in the art. Upper support 31a is rotatably fixed at its proximal end to right side wall 21 to allow it to be rotated into a parallel position with upper support 32a to facilitate carrying. Both legs are telescopingly adjustable and lower supports 31b, 32b slide into, and lock inside via lock pins 36, 37, upper supports 31a, 32a as is known in the art, to raise or lower the operating height of pipe bending machine 20. At their distal ends, each of supports 31b, 32b are connected at right angles to horizontal feet sections 33, 34.
An interchangeable bending mandrel 60 is solidly fixed to mounting bracket 20 by an assembly pin 35. Pin 35 is located at a predetermined position and connects between the distal ends of right side wall 21 and left side wall 22. Mandrel 60 is a solid forming mandrel of a predetermined thickness with a semicircular groove of predetermined size running along the center of the back side thereof. Groove 63 is formed to accommodate, for example, a pipe section 12 (as seen in phantom) with an outside diameter of 1/2 inch or, if mandrel 60 is changed, pipe with an outside diameter of 3/4 inch. As seen in FIGS. 2 and 7, mandrel 60 has an outline of a semicircle with a predetermined radius R. The phantom lines in FIG. 7 show the position of the bottom of groove 63 in the outer surface of mandrel 60.
Extending down from opposite sides of pin 35 are arms 104, 105 of rotation yoke 100 as can be seen in FIGS. 3 and 4. Arms 104, 105 are joined after a predetermined distance thereof by a stabilizing section 108 and a parallel base 112 parallel thereto. Both base 112 and section 108 have a hole of a predetermined diameter drilled through the geometrical centers thereof to accommodate a handle 114. Handle 114 has a distal end 115 and a threaded proximal end 116, which proximal end extends through base 112 and stabilizing section 108 to adjustingly contact a roller housing 130. Stabilizing section 108 has a lock section 118 fixedly attached over the center thereof to allow end 116 to extend therethrough and end 116 has a lock ring 120, as is known in the art, threadedly engaged therearound, both for a purpose to be described later.
Roller housing 130 consists of a pair of parallel side walls 132, 133 joined at the bottom thereof by a base 135. Side walls 132, 133 are dimensioned to fittingly slide against the inside surface of yoke arms 104, 105 and the bottom of base 135 rides against the top of proximal end 116. At a predetermined location above base 135, a roller pin 138 extends between walls 132 and 133. A roller 139 (as seen in phantom in FIG. 2) has a central bore therethrough, which allows roller 139 to spin freely on pin 138.
A pivotable pipe guide holder 150 (as seen in FIGS. 1 and 4) extends from the inside of right side wall 21 on a pin 152 which connects between side wall 22 and right side wall 21. Pin 152 is spaced apart a predetermined distance from the end of bending mandrel 60 and carries on it in free rotation a helically wound extension spring 155 (as seen in FIGS. 1 and 2) which spring 155 is attached to the inside of wall 22. The opposite end of spring 155 is fixed to a rotatable piece 157 which piece 157 extends from mandrel 60 down a predetermined distance. At the distal end of piece 157 is attached a rotatable pipe guide tray 159 with predetermined semi-circular grooves 163a, 163b that can cradle and steady the free end of section 12 for a purpose to be described later. Tray 159 can be reversed to put groove 163b on top by adjusting a screw 161, or other similar device.
Rotatably affixed outwardly of side wall 22 on the end of assembly pin 35 is a wheel-shaped curvature guide 170. As shown in FIGS. 5 and 6, curvature guide 170 is fixedly rotatable on pin 35 and has an inner circumference 171 bored therethrough around approximately 315° of said circumference. Guide 170 has on its inner wall at a predetermined location a stud 173 for engagement with a pin 175 protruding from the outside wall of yoke arm 105 and is fixedly fastened onto pin 35 by tightening a wing-nut 36 over a threaded end 37 as is known in the art.
As can be seen in FIGS. 2, 5 and 9, a combination semi-sleeve 180 is placed between pipe section 12 and roller 139 prior to bending operations. FIG. 9 shows a sectional view of semi-sleeve 180 taken along lines IX--IX of FIG. 8. Semi-sleeve 180 has a pre-determined semi-circular groove 183a, b (as shown in phantom in FIG. 8) to conform to the outside diameter of pipe section 12 and can be changed, as needed, to conform to a specific outside diameter dimension of a section of pipe.
The operation of pipe bending machine 10 can be seen by referring to FIGS. 2 and 6. As earlier mentioned, FIG. 6 is a fragmentary side view of a schematic of pipe bending machine 10. Motion of yoke 100 around mandrel 60 is depicted by showing three possible angular positions, denoted as A, B, C to represent circular rotation of yoke 100 of O°, 45° and 90°, respectively.
Before inserting a section of pipe into machine 10, the outside diameter dimension is measured, or otherwise verified, and the proper size mandrel 60, semi-sleeve 180 and tray 159 are selected and attached at their respective positions. FIG. 2 shows a section of pipe 12 inserted in machine 10 after the above-specified operations have been completed. Pipe guide holder 150 cradles the free end of section 12 and yieldingly releases tension on section 12 by reaction of spring 155 to the bending forces exerted on section 12 when yoke 100 is rotated.
After the properly sized parts have been selected and installed, curvature guide 170 is rotated to indicate, in conjunction with pre-determined guide marks, such as for example 66A, 66B and 66C, on mandrel 60, what degree of bend is to be put into pipe section 12. Wing nut 36 is loosened from pin 35 and stud 173B is aligned with a mark, 66B for example, and then wing nut 36 is tightened to prevent further rotation. The construction of mandrel 60, yoke arms 104, 105, curvature guide 170 and wing nut 36 on assembly pin 35 and installed in side walls 21, 22 is done to allow free rotation of arms 104, 105 only once wing nut 36 is tightened up.
Handle 114 is twisted sufficiently to allow enough of threaded screw end 116 to force housing 130, and roller 139, and semi-sleeve 180 against pipe section 12. FIG. 3 shows lock nut 120 at the top of screw end 116 and to lock roller 139 in this position, it is simply reversed down end 116 until it becomes tight against section 118. In this configuration, semi-sleeve 180 and mandrel 60 completely encircle pipe 12 and serve to distribute bending forces evenly over the pipe's surface.
Pin 175 is in the 6 o'clock position, as seen in FIG. 6 as position 175A, and will move with yoke 100 as a bend is put in section 12. If, for example, curvature guide 170 had been earlier rotated to place stud 173 at position 173B, then yoke 100, with roller 139 and semi-sleeve 180 pressuring pipe section 12, will be rotated until pin 175 contacts stud 173 as seen by 175B and 173B. This rotation will put a bend of 45° (within acceptable tolerances) into pipe section 12. In a similar manner, a bend of 90° could be obtained by adjusting stud 173 to position 173C and rotating yoke 100 until pin 175 makes contact at that point (not shown).
Many modifications and variations of the present invention are possible in light of the above teachings, and it is therefore understood that within the scope of the disclosed inventive concept, the invention may be practiced other than specifically described. | A portable pipe-bending machine that makes uniform and consistent bends of varying degree curvature in pipes is disclosed. The pipe-bending machine has a stabilizing platform to resist counter-bending forces and interchangeable elements to accommodate pipes of a different thicknesses. The pipe is forced between a solid mandrel and a movable semi-sleeve in a rotation yoke and the yoke is moved at a pre-set number of degrees, thereby putting the desired bend in the pipe. | 1 |
RELATED APPLICATION
[0001] This application is a continuation-in-part of U.S. application Ser. No. 10/733,649, filed Dec. 11, 2003.
TECHNICAL FIELD
[0002] The present invention relates generally to disposable absorbent articles and more particularly to waste worn absorbent articles.
BACKGROUND OF THE INVENTION
[0003] Absorbent articles, such as diapers, training pants and incontinence garments, provide a close, comfortable fit about the wearer and contain body exudates when such articles perform properly. Conventional absorbent articles include a front waist portion and a rear waist portion, which are releasably connected about the hips of the wearer during use by fasteners, such as adhesive tape fasteners or hook and loop type fasteners attached to a side panel, such as an elasticized ear, flap, tab or enlarged panel. For example, a conventional fastening system may have a pair of fasteners, such as adhesive tape tabs, located upon an ear or side flap structure, and a complimentary fastener, such as a taping panel, located on the outer surface of the outer cover of the diaper in the front waist portion of the diaper. In a diaper configuration, the absorbent article can be positioned between the legs of the wearer while the wearer is lying down and the adhesive tape tabs then releasably attached to the taping panel to secure the rear waist portion to the front waist portion of the diaper to secure the diaper about the waist of the wearer. In a training pant configuration, the side panels may be substantially larger than typical ears and with panel portions extending, for example, from a waist edge to a leg engaging edge.
[0004] Prior art absorbent articles having side panels and conventional fastening systems have not been completely satisfactory and user needs of comfort, fit and exudate control remain elusive goals. Typical side panels are relatively narrow with generally parallel opposed side edges. Such side panels having generally linear edges can cause skin irritation and/or injury to the user's skin, as the linear edges have a tendency to focus garment retention forces to relatively narrow regions of the user's skin. Additionally, the forces exerted on the fastening system are often inefficiently transferred and distributed across the waist region of the diaper. As a result, the fit, comfort and exudate containment of conventional absorbent articles have not been completely satisfactory.
SUMMARY OF THE INVENTION
[0005] A disposable absorbent article providing better fit, comfort and exudate control through application of an improved side panel structure. The side panel structure may be utilized, for example, on disposable absorbent articles such as diapers, disposable pull-on garments, and the like. Disposable pull-on garments include training pants, pull-on diapers, disposable underwear, and adult incontinence garments.
[0006] Side panel structures in accordance with the present invention may be embodied as ears, tabs or larger panels extending laterally from side edges of an absorbent chassis near the front waist region, the rear waist region or both.
[0007] Side panel structures in accordance with the present invention address many limitations of the prior art. Advantages provided by contoured or “shaped” panels side panels of the present invention include improved garment fit and comfort. Another advantage of such side panels is the minimization of user skin injury as garment attachment forces are transferred across a relatively wide, contoured side panel.
[0008] A side panel structure in accordance with the invention includes one or more elastic zones providing panel extensibility and a plurality of inelastic zones. Each elastic zone may include one or more elastic members, such as threads, strands, ribbons, nets and films.
[0009] A side panel structure in accordance with the invention is provided in a “shaped” configuration, with a free end, an opposite end attached to the absorbent chassis, and a pair of opposing side edges extending between the ends. At least portions of the opposing edges sides are shaped in substantially nonparallel configuration. Shaped side panels in accordance with the invention may embody opposing side edges having, for example, tapered or concave portions extending across one or more inextensible zones and/or elastic zones.
[0010] The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. The novel features which are believed to be characteristic of the invention, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a plan view of a disposable absorbent article in the unfolded configuration.
[0012] FIG. 2 is a plan view of a side panel of FIG. 1 .
[0013] FIG. 3 is a perspective view of the side panel of FIG. 2 with a cut-out detail to show an elastic construction.
[0014] FIG. 4 is a plan view of a disposable absorbent garment having large “non-shaped” side panels.
[0015] FIG. 5 is a plan view of another alternative disposable absorbent garment having “shaped” side panels.
[0016] FIG. 6 is a plan view of an alternative side panel according to the present invention.
[0017] FIGS. 7-9 are plan view of alternative disposable absorbent garments having shaped side panels.
[0018] FIGS. 10-20 are partial plan views of alternative disposable absorbent articles having shaped side panels in accordance with the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0019] For purposes of the present description, the term “side panel” is used to refer to a structure that extends laterally away from an absorbent chassis at a rear region, front region or both and being joined to the opposing waist region to allow for fitting of the absorbent article about the waist of the user. Side panels may be embodied, for example, as ear portions, tabs or larger panels. Side panels may be secured to an absorbent chassis at a side margin or may be integrated within the overall absorbent article design and/or construction. Side panels may include multiple plies of material along with one or more elastic elements such as, but not limited to, elastic threads, strands, ribbons, nets and films.
[0020] In FIG. 1 , an embodiment of an absorbent article in accordance with the invention is shown as garment 110 having a pair of shaped side panels 124 . Disposable absorbent garment 110 is of a type that can be placed against or in proximity to the body of a wearer so as to absorb and to contain various bodily exudates. It should be noted, however, that the present invention is applicable to a variety of disposable absorbent articles and garments, including training pants and a variety of adult incontinence products.
[0021] Garment 110 includes an absorbent chassis which generally defines three main regions aligned along an imaginary longitudinal axis or plane AA. These regions include a first waist region 112 (typically at the front of the user when the garment 110 is worn), a back waist region 114 , and a crotch region 116 . Diaper 110 is also characterized by a front edge 140 , a back longitudinal edge 142 , a first lateral or side edge or side margin 144 , and a second lateral or side edge or side margin 146 . In this embodiment, the absorbent chassis is formed by a liquid permeable inner layer or topsheet 152 , a liquid impermeable outer layer or backsheet (not shown), and an absorbent core 154 sandwiched between the two layers.
[0022] Side panels 124 are secured at or near the side margins 144 , 146 . Side panels 124 are used to attach the waist regions 112 , 114 together to secure garment 110 to a user. In this embodiment, side panels 124 are shaped to include a pair of nonparallel opposite side edges 124 d and 124 e. As illustrated, portions of side edges 124 d and 124 e taper inwardly toward each other. In other embodiments of the invention, portions of side edges 124 may taper outwardly, that is, the side edges may expand in relation to the distance from the absorbent chassis. A side edge 124 having an outwardly tapering configuration could be secured at one end to the front waist region of the garment 110 , with the free (wider) end being refastenably connected to the rear waist region during use.
[0023] Garment 110 also has an elastic waistband 130 positioned in this embodiment generally along the back edge 142 to facilitate fastening and to enhance the fit and seal of the garment 110 . When the hourglass-shaped garment 110 is worn, the crotch region 116 fits about the crotch of the wearer, and the front and back waist regions, 112 and 114 , fit about the corresponding waist areas. The shaped side panels 124 , wrap at least partially about the wearer to secure garment 110 during use. In other embodiments of garment 110 , waistband 130 may be provided along the front edge 140 , rear edge 142 or both.
[0024] FIG. 2 depicts shaped side panel 124 removed from the absorbent chassis. Shaped side panel 124 has a central zone 214 in which an elastic construction is situated. Extending laterally from this central elastic or elasticized zone 214 are zones 216 and 218 , which are substantially non-elasticized. Inelastic zone 216 provides a working area on which fastening materials and other accessories or structural attributes of the disposable absorbent garment may be situated. For example, a component of a hook and loop fastening system and/or an adhesive element may be situated within inelastic zone 216 . Inelastic zone 218 may provide an attachment zone within which side panel 124 is secured to the absorbent chassis.
[0025] Shaped side panel 124 has end edges 210 a and 210 b and side edges 124 d and 124 e. Side edges 124 d, 124 e include portions which are parallel (along inelastic zone 218 ) and portions which converge (along zone 214 and inelastic zone 216 ). Side panel 124 stretches, in the lateral direction (denoted by arrows XX).
[0026] FIG. 3 provides a perspective view and partial cut-out of shaped side panel 124 . Shaped side panel 124 has a top layer 318 and a bottom or base layer 320 . The two layers 318 , 320 preferably extend the total width and length of side panel 124 . Both base layer 320 and top layer 318 are preferably a breathable, disposable material such as propylene fabric, breathable polyethylene/polypropylene films, or non-porous films (or combinations of these materials). Base layer 320 and/or tope layer 318 may include woven and/or non-woven fabrics. Base layer 320 and top layer 318 adhere to one another, thereby sandwiching and securing a plurality of elastic elements 322 therebetween. Elastic elements 322 may include, for example, one or more of threads, ribbons, mesh, apertured film and other films. Thread-form elastic elements 322 , as shown in FIG. 3 , may be substituted, in alternative embodiments, by suitable elastic elements such as elastic strands of different construction, nets, threads, ribbons, and elastic glue beads.
[0027] The elasticized zone 214 of side panels 124 may be implemented in a variety of ways. For example, an elastic zone 214 may contain a single piece of stretchable elastic material or a combination of individual pieces or panels of elastic material. The elastic zone or at the least individual pieces or panels of the elastic zone may comprise elastic composite materials or non-stretchable materials which have been rendered elastically contractible by means known to those skilled in the art. In some embodiments, the elastic zone includes a two-ply stretch panel comprising a top layer, a bottom layer and a plurality of intermediate elastic ribbons. In another configuration, the elastic zone may be provided by a substantially non-elastomeric material, such as polymer films, woven fabrics, non-woven fabrics, or the like such as described above as being suitable for the outer cover or bodyside liner. Such an elastic zone could be modified to render portions elastically contractible to provide the desired elastic properties. In another example, the elastic material may be latent, in which case the elastic material would initially have non-elastomeric properties, but would later be activated to impart elastomeric properties to the stretch panel by any of various means known to those skilled in the art. Additional details of non-shaped side panel construction, including embodiments using aligned elastic threads, are disclosed in U.S. Ser. No. 10/733,649, and U.S. Ser. No. 11/113,114, and each application being incorporated by reference herein.
[0028] FIG. 4 , provided for comparative purposes only, depicts a disposable absorbent garment 410 having a pair of “non-shaped” side panels 414 . Side panels 414 are separately attached to a central body 420 of garment 410 . Side panels 414 include side edges 415 , 416 that are generally parallel, with side edge 416 defining at least a portion of a waist edge 442 of garment 410 and side edge 415 defining at least a portion of a leg edge. Side panels 414 have a non-elasticized zone 414 b that is positioned outboard of the side margins 444 , 446 of the garment 410 and a second non-elasticized zone 414 a, at least a portion of which is attached inboard of the side margin 444 , 446 . Thus, a central elastic zone 414 c is situated outboard of the side margin 444 , 446 and not directly attached thereto. When garment 410 is worn, the central elasticized zone 414 a allows the side panel to stretch in a lateral direction. Accordingly, during garment use side panels 414 allow for stretching about the waistline of the user. In another embodiment of the invention, another pair of side panels 414 may be secured near the front waist region providing a garment 410 with 4 side panels 414 .
[0029] FIG. 5 depicts an alternative disposable absorbent garment 510 according to the invention. Certain aspects of garment 510 are numbered similarly to corresponding aspects of garment 410 . In comparison to the side edges 415 , 416 of FIG. 4 , garment 510 includes side edges 517 , 518 which are substantially nonparallel across portion of side panels 414 . For example, portions of side edges 517 , 518 within elastic zone 414 c and inelastic zone 414 b are generally tapered resulting in a reduction of side panel 414 width in a transverse direction of garment 510 . While a side panel 414 with generally linear taper is shown in FIG. 5 , other side panel 414 shapes may include curves or combinations of lines and curves. For example, FIGS. 8, 12 , 13 , 15 and 17 illustrate side panels with portions of side edges extending in nonlinear manners.
[0030] FIG. 6 depicts an alternative embodiment of a side panel 610 suitable for use with embodiments according to the present invention. Side panel 610 illustrated therein differs from the previously described side panels ( 124 , 210 , 414 ) in that side panel 610 includes two elasticized zones 614 a and 614 b. Elasticized zones 614 a, 614 b may be equidistantly spaced apart on either side of the longitudinal centerline AA. The spacing of the elasticized regions 614 a, 614 b creates right and left non-elasticized or dead zones 616 , 618 , as well as central non-elasticized region 650 . The elasticized regions 614 a, 614 b imparts elasticity to side panel 610 in the lateral directions XX. Side panel 610 includes side edge 620 which extends in a linear manner across inelastic zones 618 , 650 , 616 and elastic zones 614 a, 614 b, and another side edge 622 which extends in a parallel manner to side 620 within zones 618 and 614 a, and extends toward side edge 620 in a tapering manner within zones 650 , 614 b and 616 .
[0031] Referring to FIGS. 7 and 8 , a disposable absorbent garment 910 is shown having a central body 920 and ear- and tab-shaped side panels 924 positioned proximate to a waist edge. Side panels 924 have inner and outer nonelasticized zones 924 a, 924 b, and a central elasticized zone 924 c situated therebetween. FIGS. 7 and 8 illustrate side panels 924 having shaped nonelasticized regions 924 a and 924 b, as, for example, portions of side edges of side panels 924 converge within the inelastic zone(s) 924 a, 924 b. In both designs, portions of the side edges of the outer nonelasticized regions 924 b are rounded or curved.
[0032] Now turning to FIG. 9 , yet another variation of side panel 924 is shown applied to a training pant 910 . In this embodiment, side panel 924 is substantially larger than ear-shaped side panel 924 of FIGS. 7 and 8 , and includes a waist edge and a leg engaging edge 930 . Side panel 924 is defined by nonelasticized zones 924 a and 924 b having different geometries.
[0033] FIGS. 10-20 illustrate further aspects of the present invention. In each example, a disposable absorbent garment is shown having a central body and side panels in the form of ears, tabs or even larger panels. While these illustrated embodiments have side panels with inner and outer nonelasticized regions and a central elasticized region situated therebetween, other side panel embodiments may have a plurality of both elasticized and nonelasticized regions, configured for example as shown in FIG. 6 .
[0034] The exemplary embodiments of FIGS. 10-20 illustrate a variety of differently configured side panels, in ear, tab or even larger form. FIGS. 10-17 represent side panels which are generally symmetrical about an axis perpendicular to a longitudinal axis of the absorbent chassis. Opposite side edges of side panels of these embodiments would align if folded about the center axis. In comparison, FIGS. 18-20 represent side panels which are asymmetric about a center axis.
[0035] Turning to FIG. 10 a, the side panel 1010 is shown applied at a side margin 1046 of a disposable absorbent article near waist edge 1040 . Side panel 1010 has nonelasticized regions 1012 , 1014 of different geometries. In the embodiment of FIG. 10 , the nonelasticized regions 1012 , 1014 have side edges which are generally parallel, while the side edges of elasticized region 1016 taper inwardly toward outer nonelasticized region 1012 . A fastening component 1018 , such as a hook and loop component is affixed or defined within nonelasticized region 1012 . Fastening component 1018 may extend generally between the side edges of the side panel, or alternatively, may extend within only a portion of nonelasticized region 1012 .
[0036] FIG. 10 a illustrates a side panel 1010 in a “tab” configuration, while FIG. 10 b shows a side panel 1010 with a substantially larger area extending generally from the waist edge to a leg edge and adapted to engage a user's leg during use.
[0037] Now turning to FIG. 11 , a side panel 1110 is shown applied at a side margin 1146 of a disposable absorbent article near waist edge 1140 . Side panel 1110 has nonelasticized regions 1112 , 1114 of different geometries. In the embodiment of FIG. 11 , the outer nonelasticized regions 1112 as well as in inward portion of nonelasticized region 1114 have side edges which are generally parallel, while the side edges of elasticized region 1116 and an outer portion of nonelasticized region 1114 taper inwardly toward outer nonelasticized region 1112 .
[0038] FIG. 11 a illustrates a side panel 1010 in an “ear” or “tab” configuration, while FIG. 11 b shows a side panel 1110 with a substantially larger area extending generally from the waist edge and having a leg edge adapted to engage a user's leg during use.
[0039] Now turning to FIG. 12 , a side panel 1210 is shown applied at a side margin 1246 of a disposable absorbent article near waist edge 1240 . Side panel 1210 has nonelasticized regions 1212 , 1214 of different geometries. In the embodiment of FIG. 12 , the nonelasticized region 1214 has side edges which are generally parallel, while the side edges of elasticized region 1216 and nonelasticized region 1212 taper inwardly. Similar to the embodiments of FIGS. 10 b and 11 b, side panel 1212 (and the side panels of FIGS. 13-20 ) can also be implemented as a substantially larger panel having, for example, a waist edge and a leg engaging edge.
[0040] Now turning to FIG. 13 , a side panel 1310 is shown applied at a side margin 1346 of a disposable absorbent article near waist edge 1340 . Side panel 1310 has nonelasticized regions 1312 , 1314 of different geometries. In the embodiment of FIG. 13 , the inward portion of nonelasticized region 1314 has side edges which are generally parallel, while the side edges of elasticized region 1316 , an outer portion of nonelasticized region 1314 , and nonelasticized region 1312 taper inwardly, in a concave manner.
[0041] FIG. 14 illustrates a side panel 1410 applied at a side margin 1446 of a disposable absorbent article near waist edge 1440 . Side panel 1410 has nonelasticized regions 1412 , 1414 of different geometries. In the embodiment of FIG. 14 , the inner nonelasticized region 1414 has side edges which are generally parallel, while the side edges of elasticized region 1416 and outer nonelasticized region 1414 taper inwardly. Fastening component 1418 may extend generally between the side edges of the side panel or alternatively, may extend within only a portion of nonelasticized region 1412 .
[0042] FIG. 15 illustrates a side panel 1510 as applied at a side margin 1546 of a disposable absorbent article near waist edge 1540 . Side panel 1510 has nonelasticized regions 1512 , 1514 of different geometries. In the embodiment of FIG. 15 , the inward portion of nonelasticized region 1514 has side edges which are generally parallel, while the side edges of elasticized region 1516 , an outer portion of nonelasticized region 1514 , and nonelasticized region 1512 taper inwardly, in a convex manner.
[0043] FIG. 16 shows a side panel 1610 as applied at a side margin 1646 of a disposable absorbent article near waist edge 1640 . Side panel 1610 has nonelasticized regions 1612 , 1614 of different geometries. In the embodiment of FIG. 16 , the nonelasticized region 1614 and elasticized region 1616 have side edges which are generally parallel, while the side edges of nonelasticized region 1612 taper inwardly.
[0044] FIG. 17 shows a side panel 1710 as applied at a side margin 1746 of a disposable absorbent article near waist edge 1740 . Side panel 1710 has nonelasticized regions 1712 , 1714 of different geometries. In the embodiment of FIG. 17 , the nonelasticized region 1714 and elasticized region 1716 have side edges which are generally parallel, while the side edges of nonelasticized region 1712 taper inwardly, in a concave manner.
[0045] FIG. 18 shows a side panel 1810 as applied at a side margin 1846 of a disposable absorbent article near waist edge 1840 . Side panel 1810 has nonelasticized regions 1812 , 1814 . In the embodiment of FIG. 18 , the nonelasticized regions 1812 , 1814 have side edges which are generally parallel, while one of the side edges of elasticized region 1816 tapers inwardly.
[0046] FIG. 19 shows a side panel 1910 as shown applied at a side margin 1946 of a disposable absorbent article near waist edge 1940 . Side panel 1910 has nonelasticized regions 1912 , 1914 of different geometries. In the embodiment of FIG. 19 a, the nonelasticized region 1914 has side edges which are generally parallel, while one of the side edges of elasticized region 1816 and one of the edges of nonelasticized region 1912 taper inwardly. In comparison, FIG. 19 b shows a side edges which are parallel across zone 1914 and a portion of zone 1916 and then taper inwardly across the balance of zone 1914 and zone 1912 . FIG. 19 b represents an elastic zone 1916 having both parallel and non-parallel side edges.
[0047] FIG. 20 shows a side panel 2010 as shown applied at a side margin 2046 of a disposable absorbent article near waist edge 2040 . Elastic composite band 2010 has nonelasticized regions 2012 , 2014 of different geometries. In the embodiment of FIG. 20 , a portion of nonelasticized region 2014 and nonelasticized region 2012 have side edges which are generally parallel, while one of the side edges of elasticized region 2016 and another portion of nonelasticized region 2014 tapers inwardly.
[0048] Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps. | A disposable absorbent article defining an absorbent chassis adapted to wrap around portions of a torso and a pair of side panels adapted to secure the absorbent chassis about the torso during use. The side panels include at least a pair of substantially inextensible zones and a zone of substantial elasticity providing partial extensiblity to the side panels. The side panels may be secured to the chassis at one of the inextensible zones and be provided with a fastener component at another inextensible zone. At least portions of opposed edges of the side panels are shaped into a nonparallel configuration to improve fit, comfort and exudate control of the absorbent article. | 0 |
This is a continuation of application Ser. No. 08/707,787 filed Sep. 4, 1996, now abandoned.
FIELD AND BACKGROUND OF THE INVENTION
The present invention relates in general to gas and oil production from subsea sources and, in particular, to a heat exchanger for use on a subsea pipeline for maintaining an acceptable temperature of the gas and oil produced.
Heating and cooling of oil and gas produced from subsea wells is often desirable.
Initially, wellstream temperatures often exceed the maximum operating temperatures of downstream flowline coatings and insulation materials. These maximum operating temperatures are usually about 300° F. (149° C.).
Currently, known methods for cooling the wellstream employ conventional heat exchangers located adjacent the wellhead on the seabed. The cooling fluid is produced water pumped at high pressure from an associated production platform through a separate pipeline. The operation of the heat exchanger must be carefully controlled to prevent the wellstream temperature exiting from the heat exchanger from exceeding these maximum operating temperatures, and also to avoid overcooling the gas or oil wellstream. If the wellstream is overcooled, gas hydrate or wax plugs could form and block the flowline.
The gas temperature of a wellstream decreases dramatically as it expands and passes through the wellhead choke in the pipeline due to Joule-Thomson cooling. This can occur after startup of a subsea well with a gas cap and also during steady state operation. This cooling effect could also result in flowline pluggage by gas hydrate or wax formation downstream of the choke.
Chemical inhibitors, such as methanol, are commonly injected upstream of the wellhead choke to prevent gas hydrate formation. The wellstream pressure can also be reduced to prevent the temperature drop caused by the wellhead choke. The former technique is an expensive approach while the latter is not always possible. Alternatively, a heat exchanger could be used to add heat to the cold, expanded gas immediately downstream of the wellhead choke.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an efficient solution for maintaining an acceptable operating temperature within a pipeline or flowline for a wellstream from an undersea source.
Accordingly, a heat pipe heat exchanger is located on the seabed adjacent the wellhead surrounding the pipeline. The heat pipe may be configured to provide heat to or remove heat from the pipeline and wellstream fluids carried therein.
In one embodiment of the invention, heat is removed from the pipeline contents. A configuration is provided in which the heat transfer working fluid surrounds the pipeline within an annular evaporator. The working fluid is boiled by the heat from the pipeline and the resulting vapor flows to a heat pipe extending above the pipeline into the seawater, where it condenses, releasing the heat energy. The condensed working fluid then returns to the annular evaporator by gravity to repeat the cycle.
An alternate embodiment for heating the wellstream is provided in which the heat transfer working fluid is contained within the heat pipe below the pipeline and is warmed by the surrounding seawater, causing it to boil. The vapor flows into an annulus surrounding the pipeline, where the heat energy from the vapor is transmitted into the pipeline and wellstream fluids contained therein. The condensed vapor then returns to the heat pipe to repeat the cycle.
In a further embodiment, a heat pipe is inserted directly into the wellstream fluids through a wall of the pipeline. A portion of the heat pipe extends outwardly from the pipeline into the seawater. The heat pipe conveys heat from the wellstream fluids when the working fluid is located in the portion of the heat pipe within the pipeline. The heat pipe will heat the wellstream when it is oriented such that the heat pipe extends below the pipeline and the working fluid is in the end of the heat pipe surrounded by seawater.
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 benefits attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a schematic illustration of a subsea pipeline employing a heat pipe heat exchanger according to the invention;
FIG. 2 is a side elevation sectional view of the heat exchanger of the invention;
FIG. 3 is a side elevation sectional view of an alternate configuration of the heat exchanger of FIG. 2;
FIG. 4 is a sectional view taken in the direction of arrows 4--4 of FIG. 2;
FIG. 5 is a sectional view taken in the direction of arrows 5--5 of FIG. 3;
FIG. 6 is a sectional end view of another embodiment of a heat pipe heat exchanger according to the present invention;
FIGS. 7A-7E are sectional end views of alternate arrangements and orientations of heat pipes for use with the heat exchanger of the present invention; and
FIG. 8 is a sectional view of another embodiment of a heat pipe heat exchanger according to the present invention wherein an amount of inert, non-condensible gas is provided in the heat pipe heat exchanger to obtain a degree of passive outlet wellstream fluid temperature control.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings in general, wherein like reference numerals designate the same or functionally similar elements throughout the several drawings, and to FIG. 1 in particular, there is shown in FIG. 1 a heat pipe heat exchanger 20 according to the invention placed downstream of a wellhead 10 connected to an underwater pipeline 15. The wellhead 10 and heat pipe heat exchanger 20 are located on a seabed 16 immersed in seawater 18. The pipeline 15 is connected to a production platform 12. Wellstream fluids 14 (not shown in FIG. 1) are pumped from the wellhead 10 through pipeline 15 to the production platform 12 for use.
In FIG. 2, a first embodiment of the heat pipe heat exchanger 20 is shown which can be used for removing heat from the wellstream fluids 14 contained in pipeline 15. The heat pipe heat exchanger 20 has an annular reservoir 24 surrounding pipeline 15. Fluidically connected thereto are one or more heat pipes 22 extending generally upwardly (i.e., in an opposite direction with respect to the direction of the force of gravity) from the annular reservoir 24. A heat transfer working fluid 26 is contained within the annular reservoir 24, and the fluidically connected heat pipes 22.
While FIG. 2 shows an arrangement of three rows of heat pipes 22 extending substantially radially from the annular reservoir 24, it will be appreciated that fewer or a greater number of rows may be employed, and also in arrangements other than radial. The important aspect to be observed is that in the case of a heat pipe heat exchanger 20 employed on a pipeline 15 to extract heat from the wellstream fluids 14 contained therein (as in FIGS. 2 and 4, and 6-7 described infra) the heat pipes 22 are located generally above the reservoir 24 of liquid working fluid 26. In this way, the absorption of heat from the wellstream fluids 14 causes the working fluid 26 to evaporate. The working fluid vapor flows by pressure difference up into the heat pipes 22, where the heat is rejected into the surrounding seawater 18, causing the working fluid 26 to condense on the inside surfaces and drain/return into the annular reservoir 24 by gravity. Note that heat is rejected directly to the surrounding seawater without the need for a secondary cooling fluid like produced water returned from a production platform.
The working fluid 26 may be one of water, ammonia, methanol, or any other suitable fluid having the required properties for use in a heat pipe heat exchanger.
Referring now to FIG. 4, the arrows marked Q indicate heat flow. In this embodiment wherein heat is being removed form the wellstream fluids 14, the working fluid 26 is heated by the conduction of heat from the wellstream fluids 14 through the wall of the pipeline 15. The heat Q causes the working fluid 26 to boil and evaporate, creating a vapor indicated by arrows 50. The vapor 50 flows upwardly into the one or more heat pipes 22, and the heat 50 is conducted through the wall of the pipeline 15 into the cooler seawater 18 surrounding the heat pipes 22. This heat transfer Q from the vapor 50 state working fluid 26 causes the vapor 50 to condense back into liquid working fluid 26. Heat Q is released by the condensation of vapor 50, and the recondensed working fluid 26 drains back down into annular reservoir 24 to repeat the cycle.
FIGS. 3 and 5 show an alternate configuration in which the heat pipe heat exchanger 20 is oriented to provide heat Q into the wellstream fluids 14 contained in pipeline 15. In this configuration, the heat pipes 22 are positioned generally below the annular reservoir 24. The liquid phase or state of the working fluid 26 is thus contained within the heat pipes 22. Seawater 18 surrounding the heat pipes 22 transfers heat Q to a properly selected working fluid 26, which then boils on the inside surface of the heat pipes 22, creating vapor 50. This vapor 50 flows upwardly by pressure difference into the annular reservoir 24 and is condensed by contact with the cooler outside surface of the flowline or pipeline 15 which contains the wellstream fluids 14 to be heated. This transfers heat into the colder wellstream fluids 14. The condensed working fluid 26 drains back down into the heat pipes 22, as the heat Q is transferred into the wellstream fluids 14 through the wall of the pipeline 15, to repeat the cycle. The important aspect to be observed is that in the case of a heat pipe heat exchanger 20 employed on a pipeline 15 to add heat to the wellstream fluids 14 contained therein, the heat pipes 22 are located generally below the reservoir 24 and contain the liquid working fluid 26. In this way, the absorption of heat from the seawater 18 in the heat pipes 22 causes the working fluid 26 to evaporate and rise up into the annular reservoir 24, where the heat is conveyed into the wellstream fluids 14, causing the working fluid 26 to condense and return into the heat pipes 22 by gravity. Again, no secondary cooling fluid like produced water is required to accomplish this heat addition to the wellstream fluids 14.
The configuration of FIGS. 3 and 5 is useful for transferring heat to the wellstream fluids 14 at a point downstream of a wellhead choke to prevent formation of gas hydrates and wax plugs within the pipeline 15. Again, various numbers and configurations of heat pipes 22 may be employed as described in connection with the embodiments of FIGS. 2 and 4.
In each of the previous embodiments of FIGS. 2-5, (and FIGS. 7A-7E, infra) the actual flow of the wellstream fluids 14 within pipeline 15 is not restricted or otherwise affected by the addition of the heat pipe heat exchanger 20 thereto.
Another embodiment of the invention is shown in FIG. 6, used to remove heat from the wellstream fluids 14, in which the one or more heat pipes 22 actually extend through the wall of the pipeline 15 into the wellstream fluids 14. This allows direct heat exchange between the wellstream fluids 14 and the one or more heat pipes 22. As shown, the heat pipes 22 extend substantially upwardly above the pipeline 15 since this embodiment is configured for heat removal from the wellstream fluids 14. The heat pipes 22 may contain an optional hydrogen getter 100 of known composition, which can be used to prevent the formation of unwanted gases and compounds within the heat pipe 22. Insulation 40 can also be provided to surround pipeline 15 as well.
FIGS. 7A through 7E show alternate heat pipe 22 arrangements which are envisioned for use with the present invention. While FIGS. 7A-7E are shown for removal of heat from wellstream fluids 14, it will be readily understood that arrangements of heat pipes 22 for heat addition into the wellstream fluids 14 can be easily made by locating the heat pipes 22 of FIGS. 7A-7E as described earlier, such as with the embodiments of FIGS. 3 and 5.
In each of the disclosed embodiments, the heat exchange process is controlled by pre-selecting an appropriate working fluid 26 for the application and its design requirements. No additional control is required. The heat exchanger of the invention will continue to work efficiently even as the wellstream fluids 14 temperature decreases over time.
The heat pipe heat exchanger 20 according to the present invention can be fabricated from a simple pipe-in-pipe structure, and is economically efficient. Conventional materials such as carbon steel may be used for the heat pipes 22 if the surfaces exposed to seawater are coated with TEFLON® or other corrosion resistant materials. Hydrogen getters 100 may be used with any of the disclosed embodiments to prevent internal degradation of the heat pipes 22.
Further, as described above the function of the heat pipe heat exchanger 20 can be reconfigured from heating to cooling and vice versa simply by reorienting the heat pipes 22 in relation to the annular reservoir 24. By varying the number and size of the heat pipes, the effectiveness of the heat exchanger can be controlled as well.
An additional advantage of the present invention is its ability to obtain a degree of passive outlet wellstream fluid temperature control. This aspect is described as follows and in connection with FIG. 8. While conventional heat exchangers (tube-and-shell and tube-in-tube) would normally require a control system to maintain the outlet wellstream fluids 14 temperature below a specified maximum value, or so as not to overcool the wellstream fluids 14 as the wellhead aged over time, the heat pipe heat exchanger 20 of the present invention can be engineered to passively control outlet temperatures. This is accomplished by the use of a known amount of inert, non-condensible gas (such as argon) which is provided in the heat pipe heat exchanger 20 along with the working fluid 26. Initially, when the wellstream fluids 14 from the wellhead 10 are hot, the working fluid 26 would operate at a relatively high saturation temperature which would compress the non-condensible gas into a small volume at the end of the heat pipes 20 during operation. This non-condensible gas "pocket" blocks a small portion of the heat transfer surface area within the heat pipes 22 and causes it to be inactive. However, as the well ages and the wellstream fluids 14 produced thereby decrease in source temperature, the working fluid 26 temperature and saturation pressure would also reduce. This would allow the non-condensible gas pocket to expand, covering more of the heat pipe 22 heat transfer surface and preventing steam from condensing thereon. By reducing the surface area available for heat transfer, less wellstream fluids 14 temperature drop would occur as it passed through the heat pipe heat exchanger 20. Such passive temperature regulation requires no external control system or power.
The heat pipe heat exchanger according to the present invention thus has several advantages. It is a completely passive design with no moving parts, and no power requirement or controls. Some embodiments of the invention allow for full bore flowlines or pipelines 15 that would permit pipeline "pigs" to pass therethrough for cleaning. Simple fabrication is involved by using standard pipe or tube and welded pipe-in-pipe design. The heat pipe heat exchanger according to the present invention transfers heat directly to the surrounding seawater, while conventional shell and tube or tube-in-tube heat exchangers require a secondary fluid stream to transfer heat with the wellstream fluids. Produced water is normally returned from the production platform through a separate pipeline to the conventional sub-sea heat exchangers. Accordingly, a heat pipe heat exchanger according to the present invention could eliminate many miles of secondary fluid pipeline between the production platform and the wellhead. Depending on well requirements, heat can be either added to or removed from the wellstream fluids, and the flexibility of the design is apparent in that the number, size, and location of the heat pipes and the working fluid are design parameters that can be varied to meet specific sub-sea heat pipe heat exchanger applications. If necessary, enhanced surface can be used on the inside surfaces of the flow line to increase surface area, thus increasing heat transfer with the wellstream fluids. Enhanced surface can also be used on the outside surface of the heat pipes themselves, thus increasing the heat transfer capability with the seawater. This enhanced surface can be any of the conventional forms including longitudinal or transverse fins. The present invention is less expensive to manufacture, since high flow line pressures, high produced water pressures, and external hydrostatic seawater pressures traditionally dictate high pressure designs. The use of produced water as the secondary coolant in traditional approaches also dictates the use of expensive corrosion-resistant alloys like titanium. The heat pipe heat exchanger according to the present invention is a relatively simple pipe-in-pipe construction with only flow line pressure and hydrostatic head to deal with. Without high-pressure, corrosive produced water, the heat pipe heat exchanger design of the present invention is relatively simple and less expensive alloys can be used. Predictable life is obtained in that hydrogen gas generated by the corrosion process and which can deffuse into the working fluid volume can be addressed by the provision of low-temperature hydrogen getters placed inside the heat pipe to prevent performance degradation with time.
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. | A heat pipe heat exchanger for regulating the temperature of a wellstream fluid conveyed in a subsea pipeline from a wellhead has an annular reservoir surrounding a section of pipeline adjacent the wellhead. One or more heat pipes extend from the annular reservoir into the seawater. In a heat removal configuration, a working fluid is contained within the annular reservoir. The working fluid boils and is evaporated by heat from the wellstream fluid and forms a vapor, which rises upwardly into and is condensed within the heat pipes, releasing heat into the surrounding seawater. The recondensed working fluid flows back down into the reservoir to repeat the cycle. In a heat providing configuration, the working fluid is contained in the heat pipes, where it is boiled by heat transferred from the surrounding seawater. The resulting vapor rises upwardly into the annular reservoir and the heat is transferred to the cooler wellstream fluids. Other embodiments involve having the one or more heat pipes inserted through the pipeline wall. | 4 |
BACKGROUND
1. Field
The technology of the present application relates generally to construction and building systems and methods, and more specifically, to systems and methods for marking the outline or location of an object on an opposing surface.
2. Background
Marking where to cut or drill construction materials is a common component of all building and construction. For example, marking and locating utility outlets or window and door openings on the blind side of drywall panels is a task required of virtually every building project. Manually measuring and marking where to locate these cuts, openings, or holes requires transposing measurements previously made from desired features to the blind side of a panel. This process is time consuming and inaccurate because points of reference are often irregular, uneven, and/or difficult to reach.
To address this problem, several devices exist for marking the outline or location of an object, such as an electrical outlet box, window or door, water or gas line, or similar features, on an opposing panel. That said, these devices are cumbersome and their applications are limited to marking outlines or locations of one or a few different types of objects on an opposing drywall panel. There is therefore a need in the art for a simple, accurate, and versatile method of marking the outline or location of nearly any object on a variety of opposing surfaces.
SUMMARY
Embodiments disclosed herein address the above stated needs by providing a system and method for marking opposing surfaces of various sizes, shapes, and materials through the use of a transferable marking substance. The foregoing, as well as other features, utilities, and advantages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention as illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a front perspective view of one embodiment of an apparatus for applying a marking substance to a template surface;
FIG. 2 shows a side plan view of another potential embodiment of an apparatus for applying a marking substance to a template surface;
FIG. 3 shows a flowchart for a method of marking opposing surfaces;
FIG. 4 illustrates an exploded view of one embodiment of a method of marking opposing surfaces;
FIG. 5 illustrates an exploded view of another potential embodiment of a method of marking opposing surfaces;
FIG. 6 illustrates an exploded view of another potential embodiment of a method of marking opposing surfaces; and
FIG. 7 illustrates a front plan view of another potential embodiment of an apparatus for applying a marking substance to a template surface;
DETAILED DESCRIPTION
The technology of the present application will be further explained with reference to FIGS. 1 through 7 . It will be apparent to those skilled in the art that various changes in the methods and apparatuses disclosed herein may be made without departing from the scope of the invention, which is defined in the appended claims.
FIG. 1 shows a front perspective view of one embodiment of an apparatus 100 for applying a marking substance 112 to a template surface 101 . The marking substance 112 may be transferred to an opposing blank surface (not shown), as explained further with reference to FIGS. 3 through 6 . Transferring marking substance 112 from template surface 101 to the opposing blank surface allows the user to make accurate cuts in the newly marked blank surface.
In this embodiment, apparatus 100 may comprise a hollow tube 103 having a chamber 102 , a plunger 104 , a handle 106 , and a tip 108 . Chamber 102 may be filled with marking substance 112 formulated to imprint upon any surface pressed against it. In addition, tip 108 may feature an offset 114 , which elevates an opening 116 of tip 108 above the template surface 101 . Thus, apparatus 100 may dispense a bead of marking substance 112 with a consistent diameter, while at the same time, offset 114 may stay in constant contact with the template surface 101 to guide apparatus 100 and facilitate the accurate application of marking substance 112 . Opening 116 of tip 108 may be sized to accommodate the necessary marks to the blank surface. For example, in one embodiment, opening 116 may be sized to dispense a bead of marking substance 112 that is approximately 1/16 inch in diameter. Of course, the size of opening 116 is largely a matter of design choice, environment of use, and viscosity of marking substance 112 .
Generally, marking substance 112 may be a highly viscous liquid or semi-solid material that is impregnated with a visible ink, dye, or other coloring agent as is generally known in the art. Marking substance 112 may also be impregnated with a machine readable medium such as a radio-opaque substance, magnetic substance, metal filings, or other materials to facilitate the automated detection of marking substance 112 . Preferably, marking substance 112 is washable, slow to dry, and does not spread or distort after application. Also, marking substance 112 should be compatible with most construction equipment, including drills, saws, nailers, routers, and other common building tools. Marking substance 112 may be formulated as generally known in the art or it may be purchased commercially.
FIG. 2 shows a side plan view of another embodiment of an apparatus for applying marking substance 112 . Apparatus 200 may be used to discharge marking substance 112 from a cartridge 202 having a chamber 203 . In this embodiment, apparatus 200 may comprise a shell 204 and a plunger 206 operably connected to a handle 208 through a ratchet system (not shown) configured as generally known in the art. Apparatus 200 may operate similarly to a caulking gun by causing plunger 206 to move through chamber 203 to discharge marking substance 112 from cartridge 202 .
FIG. 7 shows a front plan view of another embodiment of an apparatus for applying marking substance 112 . Apparatus 700 may be used to discharge marking substance 112 from a pressurized container 702 having a valve 704 and a nozzle 706 . When a user presses nozzle 706 , valve 704 opens, allowing marking substance 112 to flow from the highly pressurized environment within the container to the outside air. Apparatus 700 may operate similarly to pressurized containers used to dispense products such as SILLY STRING®, EASY CHEESE®and others. Alternatively, container 702 may be connected to a pressure source 708 , such as an air compressor or the like, instead of being pressurized.
While three embodiments of an apparatus for applying a marking substance have been described, one of ordinary skill in the art would readily understand that the apparatus can be practiced by other than the described embodiments, which are presented for the purpose of illustration rather than limitation.
FIG. 3 shows a flowchart for a method 300 of marking an opposing surface using, for example, apparatus 100 , 200 , 700 and marking substance 112 described above. Method 300 may be used to mark opposing surfaces having any size or shape and being formed of virtually any material. First, the user may apply a bead of marking substance to a template surface to be transferred to an opposing blank surface, step 302 . This bead may comprise a continuous or discontinuous channel that outlines the perimeter of a construction feature such as an electrical box, piping outlet, architectural feature, window or door, or other similar feature to be transferred to an opposing blank surface. The bead may also be a single dot marking the location of a drill hole, wall stud, or otherwise. Once the marking substance has been applied, the user may either press the blank surface against the template surface, step 304 , or press the template surface against the blank surface, step 306 , to transfer the marking substance from the template surface to the blank surface. Pressing the template and blank surfaces together may be accomplished manually or through the use of equipment such as a press or other suitable device. After pressing the template and blank surfaces together, the user separates the surfaces, step 308 . The outline or marks for accurate cutting are now reflected on the blank surface, and the user may cut or drill holes in the blank surface that accurately reflect the size, shape, and location of the corresponding template features, step 310 . These cuts may be made manually or through the use of automated machinery.
FIG. 4 illustrates an exploded view of an exemplary embodiment of the above described method. In this embodiment, method 400 may be used to prepare drywall for mounting over features like electrical outlets, HVAC vents, gas and water pipes, and more. As shown in FIG. 4 , surface 402 may comprise various construction features 403 such as, for example, light switch 404 , electrical outlet 406 , gas pipe 408 , and similar features, to be reflected on a blind side 410 of a sheet of drywall 412 . After applying marking substance 112 to outer perimeters 405 , 407 , 409 of features 404 , 406 , 408 , the user may press blind side 410 against features 404 , 406 , 408 , and outlines 404 ′, 406 ′, and 408 ′ of features 404 , 406 , 408 will be transferred to blind side 410 where cut-outs are required. The user may then cut appropriately sized and accurately located holes in the drywall panel without the need for time consuming and error prone measurements.
FIG. 5 illustrates an exploded view of another exemplary embodiment of the above described method. Method 500 may be used to accurately locate drill holes for mounting appliances, lighting, equipment, and the like, under wall cabinets. For example, in this embodiment, a user may apply beads of marking substance 112 to the tips of mounting fasteners 502 before pressing an appliance 504 and attached mounting fasteners 502 against a cabinet base 506 . Marking substance 112 is transferred from mounting fasteners 502 to cabinet base 506 , allowing the user to set appliance 504 aside and drill mounting holes accurately on outlines 502 ′.
FIG. 6 illustrates an exploded view of yet another exemplary embodiment of the above described method. Method 600 may be used to prepare toe kicks for installation under level base cabinets that sit above uneven floors. In this embodiment, a user may apply a bead of marking substance 112 along an outer bottom edge 602 of a base cabinet 604 and press a toe kick 606 against outer bottom edge 602 . Marking substance 112 is transferred to toe kick 606 , which can then be cut along a line A reflecting the slope or sag of the uneven floor 608 .
While three specific embodiments of the disclosed method are provided to enable any person skilled in the art to make or use the present invention, one of ordinary skill in the art will readily understand that the present invention could be used in multiple environments, and that the specific examples described above are used for illustrative purposes only. For example, the method described above could also be used to hang wall art or mount window treatments or for a variety of other applications. Various modifications to the described embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. | The technology of the present application provides a system and method for marking opposing surfaces of varying sizes, shapes, and materials. This system and method allow a user to transfer the outline or location of a relevant feature such as, for example, a fastener, utility outlet, architectural feature, or window or door, from one surface to another through the use of a transferable marking substance, thereby eliminating the need for complicated and limited fixtures or time consuming and often inaccurate manual measurements. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to a system for evacuating a viscous product from within a plastic bag that is constrained by a bin. More specifically, the present invention relates to such a system that includes adjustable scrapers. The adjustable scrapers reduce the risk of harm to the plastic bag and once pumping is complete, ease removal from the plastic bag of the plate carrying the scrapers and the pumps.
Bin unloading systems are customarily used in the food processing and pharmaceutical industries. Viscous products such as tomato paste, icing and medical preparations are provided to manufacturers in bulk in large plastic bags which are placed within bins and subsequently unloaded by floating a platform generally referred to as a follower plate on the surface of the product and pumping the product up through the follower plate.
It is important that the evacuation of the product from the bag be complete to avoid waste. Viscous products often adhere to the bag which may collapse as the product is evacuated to overlie pockets of the product. Since gravity forces the bag to conform to the size of the bin, it is known to attach scrapers to the follower plate which extend laterally into close proximity to the bin supported bag wall to remove product clinging thereto as the product is evacuated.
However, removal of the follower plate from the unloaded bag is often problematical. The bag may collapse over the follower plate and the laterally extending scrapers may damage the bag as the follower plate is withdrawn from the collapsed bag. In addition, the upward scraping of the bag may cause product to be deposited on the top of the follower plate and/or the floor in the area around the bin, requiring cleaning to avoid health hazards and safety issues. Moreover, the product may create a seal between the scrapers and the bin supported bag, and withdrawal of the follower plate may create a vacuum which resists the withdrawal of the follower plate from the bag and/or pulls the bag from the bin as the follower plate is withdrawn.
One known system for bin unloading injects air between the plate and the bag during withdrawal of the plate to keep the bag within the bin. While the injection of air facilitates to some extent the removal of the plate from the bag; it does not address the upward scraping and/or bag damage issues. Moreover, injecting air between the plate often may not be acceptable to the food processors for other reasons.
Another known system utilizes inflatable scrapers to assist in unloading the product from the bag. Accordingly, when the plate is lowered the scrapers are inflated so that they contact the interior walls of the bag. Before the plate is withdrawn the scrapers are deflated so that they are no longer in contact with the bag, preventing the bag from being re-scraped when the plate is removed and eliminating the vacuum created during pumping. Inflated scrapers are generally not rigid enough to adequately scrape the bag and the scrapers themselves may be punctured during the scraping operation resulting in delay and down time for replacement.
Accordingly, it is an object of the present invention to obviate many of the above problems in known systems and to provide a novel system and method for unloading a viscous product contained within a bag constrained by a bin.
One embodiment of the present invention avoids the problems of the known systems by mounting movable scrapers at the edges of the plate selectively extended to remove product adhering to the interior surfaces of the bag when the plate is lowered and retracted out of contact with the interior of the bag upon withdrawal of the plate.
It is another object of the present invention to provide a novel bin unloading apparatus and method that reduces risk of injury to the bag containing a viscous product.
It is yet another object of the present invention to provide a novel bin unloading apparatus and method that eliminates the vacuum created during pumping and eases removal of a follower plate from the bag containing a viscous product.
It is still another object of the present invention to provide a novel bin unloading apparatus and method with scrapers that can be extended or retracted to vary the lateral distance between the scrapers and the bin.
It is a further object of the present invention to provide a novel bin unloading apparatus and method with scrapers that can be extended or retracted to laterally center a follower plate within the bag containing a viscous product that is constrained by a bin.
It is an additional object of the present invention to provide a novel method for maintaining a clean work area when unloading a viscous product from a bag constrained by a bin.
These and many other objects and advantages of the present invention will be readily apparent to one skilled in the art to which the invention pertains from a perusal of the claims, the appended drawings, and the following detailed description of the preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevation in cross-section illustrating a bin unloading system in accordance with one embodiment of the present invention.
FIG. 2 is an illustration of a spring biased scraper which may be used with the embodiment of FIG. 1 .
FIG. 3 is an illustration of a scraper that has been retracted so as not to extend beyond the lateral edge of the plate.
FIG. 4 is an overhead view of one embodiment of the present invention with the scrapers extended laterally.
DESCRIPTION OF PREFERRED EMBODIMENTS
Like numerals represent like components throughout the several drawings.
Referring to FIG. 1 , a bin unloading system 10 includes a bin 12 for constraining a bag 14 that contains a viscous product. The bin may be constructed of any material, i.e., plastic, metal or wood, that is rigid enough to withstand the pressure created when the product is pumped out of the bag 14 and to withstand the forces exerted by the weight of the product and the lateral force of the scrapers when wiping the interior of the bag 14 .
Continuing with FIG. 1 , the bin unloading system 10 includes a follower plate 16 of any suitable conventional material. As depicted, the plate 16 is in a rest position above the bin 12 either before or after pumping has occurred. During pumping, the follower plate 16 is lowered into the bag 14 and the pumps 18 carried by the plate 16 withdraw a viscous product out of the bag 14 through the follower plate 16 . Ensuring that the maximum amount of product is evacuated from the bag scrapers 20 A, 20 B are provided to wipe the interior sides of the bag removing any product clinging thereto as the plate 16 is lowered within the bag 14 .
Each scraper 20 A, 20 B may include a flexible blade 22 that contacts the interior of the bag 14 to remove any product adhering thereto. The flexible blade 22 may be made from rubber or any other conventional wiper blade material. Any means for attaching the blade 22 to the follower plate 16 may include a hinge 24 or any other suitable conventional component that permits the position of blade 22 in relation to the bag and the follower plate to be adjusted. Any actual change in the position of the scraper 22 is accomplished with an adjustment means 26 such as an air piston or the like for adjusting and maintaining the position of the scraper.
Still referring to FIG. 1 , the blade 22 may adjusted to be in various other positions that are not shown. The flexible blade 22 of scraper 20 A is positioned so that the blade 22 extends past the lateral edge 17 of the follower plate 16 during pumping and so that the blade 22 does not extend past the lateral edge 17 of the plate 16 upon withdrawal or initial insertion into the bag. When extended into contact with the interior sides of the bag 14 , the blade 22 will scrape the bag removing any product adhering thereto when the follower plate 16 is lowered within the bag 14 . By scraping the bag 14 , the amount of viscous product which may be unloaded from the bag is increased. Note that the selective extension of the blades serves to keep the follower plate centered.
In FIG. 2 , the scraper 20 includes a tension spring 30 extending between the plate 16 and the flexible blade 22 . When the plate 16 is lowered into the bag 14 , the viscous fluid exerts an upward force against the blade 22 that may prevent continuous contact between the blade 22 and the interior sides of the bag 14 . Additionally, as the blade 22 scrapes the interior surface of the bag 14 friction exerts an upward force on the blade 22 that may also prevent continuous contact between the blade 22 and the interior sides of the bag 14 . Without the requisite contact between the blade 22 and the bag 14 , adequate evacuation of the product cannot be achieved. In order to counter the upward forces a spring 30 or other suitable resilient member may be included to provide a downward force on the blade 22 to ensure continuous contact between the blade 22 and the interior of the bag 14 throughout evacuation of the viscous product. The spring 30 may also assist in properly locating the plate 16 on the surface of the viscous product within the bag 14 .
As shown in FIG. 3 , the scraper that has been retracted so as not to extend beyond the lateral edge of the plate prevents contact of the blade 22 with the interior of the bag 14 . Once pumping is complete, contact between the interior sides of the bag 14 and the blade 22 may thus be eliminated to eliminate any vacuum created during pumping. This allows the plate 16 to be removed from within the bag 14 without the re-scraping and possibly damaging the bag 14 . It also permits the follower plate 16 to be removed from the bag 14 without withdrawing the bag from the bin.
While preferred embodiments of the present invention have been described, it is to be understood that the embodiments described are illustrative only and that the scope of the invention is to be defined solely by the appended claims when accorded a full range of equivalence, many variations and modification naturally occurring to those of skill in the art from a perusal hereof. | A system and method for unloading a viscous product from a bag constrained by a bin where movable scrapers are utilized to increase the amount of product evacuated from the bag, to prevent damage to the bag containing the product, and to ease removal of the pump after pumping is complete by breaking the vacuum created during pumping. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a magnetoresistance element for detecting a variation of magnetic field and particularly relates to a magnetic detection element which is provided with a giant magnetoresistance element with high level output, method of production of it and magnetic detection device.
2. Description of the Prior Art
Generally speaking, a magnetoresistance element (hereinafter relate to MR element) is an element whose resistance value changes depending on an angle between a magnetization direction of a thin film consisting of a ferromagnetic substance (e.g. Ni—Fe, Ni—Co, etc.) and a direction of electric current.
Resistance of the MR element as above takes a minimum value when an electric current direction and magnetization direction intersects at right angle and takes a maximum value when angle between electric current direction and magnetization direction becomes zero: i.e., both of directions are the same or reversed each other completely. Such a change of resistance value is referred to MR change rate and generally Ni—Fe and Ni—Co takes a rate of 2˜3% and 5˜6% respectively.
FIG. 9 and FIG. 10 are a side view and a perspective view respectively showing a structure of a conventional magnetic detection device.
As shown by FIG. 9, a conventional magnetic detection device is provided with a rotation shaft 41 , a disk shaped magnetic rotating body having at least one or more of uneven face of recess and protrusion on its periphery and rotating synchronously with a rotation of the rotation shaft 41 , a MR element 43 which is arranged with a gap having a predetermined distance with the periphery of the rotating body, a magnet 44 fixed to the back side of the MR element 43 for supplying a magnetic field to the MR element 43 and an integrated circuit 45 for processing an output of the MR element 43 ; and the MR element 43 consists of a magnetic resistance pattern 46 and a thin film surface 47 (magnetosensitive surface).
In the foregoing magnetic detection device, the magnetic field penetrating through to thin film surface 47 , i.e. a magnetosensitive surface of the MR element 43 changes due to the rotation of the magnetic body 42 , thereby the resistance value of the magnetic pattern 46 changes.
However, the output level of the MR element 43 used for the magnetic detection device as above is low and therefor a detection with high accuracy can not be performed. In order to overcome this problem, recently a magnetic detection element employing a giant magnetoresistance element (hereinafter refer to as GMR element) with a high level output has been proposed.
FIG. 11 shows characteristics of a conventional GMR element.
The GMR element exhibiting the characteristics shown by FIG. 11 is a laminated layers member acting as so called an artificial lattice membrane arranged in lamination of an alternate succession of a magnetic layer having a thickness of several Å to several tens Å and a non magnetic layer (Fe/Cr, and permalloy/Cu/Co/Cu, Co/Cu, FeCo/Cu) which is disclosed by an article bearing a title of “magnetoresistance effect of an artificial lattice” appearing in Journal of Japanese Applied Magnetism, Vol.15, No,51991, pp.813˜821. This laminated member has an extraordinarily high MR effect (MR change rate) comparing with the MR element as mentioned above and also is possible to obtain the same change of resistance regardless of direction of external magnetic field with respect to electric current.
In order to detect a change of magnetic field, carrying out formation of a substantial magnetosensitive surface using a GMR element, formation of electrode on each end of the magnetosensitive surface and forming a bridge circuit between these ends, connecting a power supply for a constant voltage and a constant current between two electrodes facing each other, and converting change of resistance value of the GMR element to change of voltage and then it is possible to arrange the detection of change of magnetic field being acted on the GMR element.
FIG. 12 and FIG. 13 are a side view and a perspective view, respectively, of a structure of a magnetic detection device using a conventional GMR element.
FIG. 12 and FIG. 13, this magnetic detection device comprises a rotation shaft 41 , a disk shaped magnetic rotating body as a means of providing a magnetic field change due to a rotating magnetic field synchronously with the rotation of the rotating shaft 41 and having at least one uneven surface of recess and protrusion on that rotating body, a GMR element 48 which is arranged with a gap of predetermined spacing facing the outer periphery of the magnetic rotating body 42 , a magnet 44 as a means for providing a magnetic field to the GMR element 48 and an integrated circuit 45 for processing output of the GMR element 48 ; and the GMR element 48 has a magnetic resistance pattern 49 as a magnetosensitive pattern and a thin film surface 50 .
In the magnetic detection device as above, a magnetic field penetrating through the thin film surface (magnetosensitive surface) 50 of the GMR element 48 changes due to rotation of the magnetic rotating body 42 , thereby resistance value of the magnetoresistance pattern 49 changes.
FIG. 14 is a black diagram of a magnetic detection device employing a conventional GMR element, and FIG. 15 is a detailed block diagram of a magnetic detection device employing a conventional GMR element.
A magnetic detection device shown by FIG. 14 and FIG. 15 comprises a Wheatstone bridge circuit using a GMR element 48 which is arranged with a gap having a predetermined distance with a magnetic rotating body 42 and is supplied with a magnetic field from the magnet 44 , a differential amplifier circuit 52 for amplifying an output of the Wheatstone bridge circuit 51 , a comparator circuit 53 for outputting “0” or “1” signal by comparing this output value of the differential amplifying circuit 52 with a reference value and an output circuit 54 for performing switching upon reception of the output of the comparator circuit 53 .
FIG. 16 shows an example of a circuit arrangement of a magnetic detection device using a conventional GMR element.
FIG. 16, a Wheatstone bridge circuit 51 has, for example, the GMR element 48 a , 48 b , 48 c , and 48 d on each side of it; and the GMR element 48 a and GMR element 48 c are connected to the power supply terminal VCC, the GMR element 48 b and the GMR element 48 d are grounded, each of the other end of the GMR element 48 a and that of the GMR element 48 b is connected to a connection point 55 and each of the other and of the GMR element 48 c and the GMR element 48 d is connected to a connection point 56 .
The connection point 55 of the Wheatstone bridge circuit 51 is connected to an inverse input terminal of the amplifier 59 of the differential amplifier circuit 58 through a resistor 57 , and the connection point 56 is connected to a non-inverse input terminal of the amplifier 59 through a resistor 60 and further connected to a potential dividing circuit 62 which provides a reference voltage on the basis of the voltage supplied from the power supply terminal VCC.
An output terminal of the amplifier 59 is connected to it's own inverse terminal through a resistor 63 and also is connected to an inverse input terminal of the amplifier 65 of the comparator circuit 64 ; and a non-inverse input terminal of the amplifier 65 is connected to a potential dividing circuit 66 which provides a reference voltage on the basis of the voltage supplied from the power supply terminal VCC and also is connected to an output terminal of an amplifier 65 through an resister 67 .
An output end of the comparator circuit 64 is connected to base of a transistor 69 of the output circuit 68 , collector of the transistor 69 is connected to an output terminal 70 of the output circuit 68 and is connected also to the power supply terminal VCC through a resistor 71 and the emitter of this transistor is grounded.
FIG. 17 shows a structure of a conventional magnetic detection element and FIG. 18 shows an operational characteristics of a conventional magnetic detection element.
As shown by FIG. 17, the Wheatstone bridge comprises a GMR element 48 (consisting of 48 a ˜ 48 d ) As shown by FIG. 18, as the magnetic rotating body 42 rotates, the magnetic field supplied to the GMR element 48 ( 48 a to 48 d ) changes and as shown by FIG. 18 an output corresponding to the uneven surface of recess and protrusion of the rotating body 42 can be obtained at the output end of the differential amplifier circuit 58 .
This output of the differential amplifier circuit 58 is supplied to the comparator (circuit 64 , compared with a reference value, a level to be compared, and converted to a signal of “0” or “1” and this converted signal is further waveform shaped by the output circuit 68 and as a result, signal of “0” or “1” with a sharp rise or fall can be obtained at the output terminal 70 of it as shown by FIG. 18 .
Characteristics of the GMR element used for the foregoing magnetic detection element includes, however a hysteresis with respect to applied magnetic field, and this causes reduction of sensitivity when a range of magnetic field set by the magnetic detection device is narrow, and as a result there may be a possibility that practice of detection will encounter difficulties. Since the magnetic characteristics of the GMR element is temperature dependent similar to metal films in general, there may also arise a likelihood of troubles in practice of detection when temperature in operation rises even when the element has sufficient sensitivity in the range of magnetic field set for the magnetic detection device at room temperature.
Therefore, there was a problem such that a possibility of not obtaining a sufficient output signal is expected in the case where a range of magnetic field is extremely small only in a particular portion as exemplified by partially narrowed spacing between a recess and protrusion of the rotating body facing the magnetic detection element.
Also there is problem such that, when an environmental temperature in operation is sever (e.g. higher than −40° C. and lower than 15° C.) as in a case of an automobile application, an output can not be obtained on a high temperature side. Now, for automobile application various way of usage of this element such as rotational speed detection of engine and wheel for engine control and brake control are considered.
Accordingly, the present invention is made in order to solve foregoing problems and object of this invention is to provide a magnetic field detection device having a wide environmental operational temperature range and high detection sensitivity
SUMMARY OF THE INVENTION
According to the present invention, a magnetic detection element comprises a giant magnetoresistance element, the giant magnetoresistance element is operated in a magnetic field which stays within a limit less than a magnetic field obtained by multiplying a saturation magnetic field of the giant magnetoresistance element by 0.8.
In the magnetic detection element according to the present invention, the giant magnetoresistance element is operated in a magnetic field which is larger than a field for maximizing a resistance value of the giant magnetoresistance element.
In the magnetic detection element according to the present invention, the magnetic detection element is provided with an integrated a circuit.
In the magnetic detection element according to the present invention, said giant magnetoresistance element consists of laminated layers with an alternate succession of a layer of Fe(X)Co(1−X)[0≦X≦0.3] and a copper layer, thickness of a single layer of the copper is such that the magnetic resistance change with respect to the thickness of a single copper layer takes a value in the vicinity of a second peak value, and the number of lamination of the layer with a bundle of Fe(X)Co(1−X)[0≦X≦0.3] and Cu layer counted as a single layer is more than ten and less than forty.
In the magnetic detection element according to the present invention, thickness of the layer of Fe(X)Co(1−X)[0≦X≦0.3] is more than 10 Åand less than 30 Å.
In the magnetic detection element according to the present invention, an uppermost layer of the laminated layers consists of said layer of Fe(X)Co(1−X)[0≦X≦0.3].
In the magnetic detection element according to the present invention, a protective layer is formed on the uppermost layer of Fe(X)Co(1−X)[0≦X≦0.3].
In the magnetic detection according to the present invention, a side surface of a resistance pattern which is formed as the giant magnetoresistance element is tapered off to make an angle of more than 20 degrees and less than 80 degrees with respect to a face of a base board for holding the giant magnetoresistance element.
In the magnetic detection element according to the present invention, side surface of a resistance pattern which is formed as the giant magnetoresistance element is tapered off to make an angle of more than 40 degrees and less than 65 degrees with respect to a face of a base board for holding the giant magnetoresistance element.
According to the present invention, the protective layer is formed by means of thin film treatment without releasing the vacuum produced during formation of the upper must layer.
According to the present invention, a magnetic detection device consists of a rotating magnetic body having an unevenly formed surface with recess and protrusion on a periphery thereof and being rotatable on a rotating axis, a magnet which is arranged so as to face said periphery of said rotating magnetic body and a magnetic detection element which is provided at a position at which said magnet faces periphery of said magnetic rotating body, and the magnetic detection element comprises a giant magnetic element which detects variation of magnetic field between the rotating magnetic body and the magnet caused by rotation of the rotating magnetic body and detects amount of rotation of the rotating magnetic body on the basis of result of the detection.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows magnetic characteristics of the GMR element used for the magnetic detection element according to the Embodiment 1 of the present invention.
FIG. 2 is a perspective view showing an arrangement of magnetic detection device according to the Embodiment 1.
FIG. 3 is a perspective view showing an arrangement of the magnetic detection device according to the Embodiment 1.
FIG. 4 shows the relation between the resistance change rate per unit magnetic field and number of lamination of the GMR element used for the magnetic detection element according to the Embodiment 2.
FIG. 5 shows the relation between the resistance change rate per unit magnetic field and the thickness 2 ; of the FeCo layer of the GMR element used for the magnetic detection element according to the Embodiment 3.
FIG. 6 is a sectional view showing a formation the layer of the GMR element used for the magnetic detection element according to the Embodiment 4.
FIG. 7 is a sectional view showing a formation of the layers of the GMR element used for the magnetic detection element according to Embodiment 4.
FIG. 8 ( a ) and FIG. 8 ( b ) are sectional views of a side surface of the GMR element used for the magnetic detection element according to the Embodiment 5.
FIG. 9 is a side view showing an arrangement structure of a conventional magnetic detection device.
FIG. 10 is a perspective view showing an arrangement structure of a conventional magnetic detection device.
FIG. 11 show characteristics of a conventional GMR element.
FIG. 12 is a side view showing an arrangement of a magnetic detection device using a conventional GMR element.
FIG. 13 is a perspective view showing an arrangement of a magnetic detection device using a conventional GMR element.
FIG. 14 is a block diagram illustrating a magnetic detection device using a conventional GMR element.
FIG. 15 is a block diagram illustrating a detailed magnetic detection device using a conventional GMR element in detail.
FIG. 16 shows an example of a circuit arrangement of a magnetic detection device using a conventional GMR element.
FIG. 17 shows an arrangement of a conventional magnetic detection element.
FIG. 18 shows characteristics depicting a performance of a conventional magnetic detection element.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Description of Embodiments of the magnetic detection element, production method of it and the magnetic detection device according to the present invention will be given in detail referring to accompanied drawings.
Embodiment 1
FIG. 1 shows a magnetic characteristics of the magnetic detecting element and the GMR element of which the magnetic detection element is consisted.
As shown by FIG. 1, magnetic field curve depicting the magnetic characteristics of the GMR element according to Embodiment 1 exhibit a maximum value of the resistance (hereinafter referred to as Rmax) in the vicinity of zero magnetic field and the value decreases as the magnetic field increases and assumes a saturated state at a sufficiently large magnetic field (I,g., more than 20 KOe). Now the resistance value under this saturation state is defined as Rmin. On the way of bringing back the magnetic field from the saturated state, the resistance value increases toward the point at zero magnetic field value tracing back different path from the one which is traced during increase of the magnetic field and thus so called hysteresis is exhibited.
Generally speaking, though a saturated magnetic field is meant by a minimum magnetic field which is just enough for bringing that field into saturated state, because of vagueness involved in this definition, in the present invention the saturated magnetic field is defined as “the magnetic field obtained at the intersecting point of the value obtained by adding 1% of Rmin to Rmin (i.e. Rmin×1.01) and the magnetoresistance curve obtained through increase of the magnetic field.”
As shown by FIG. 2 and FIG. 3, the magnetic detection device comprises the MR element has at least one uneven surface of recess and protrusion on the periphery of it and also comprises a disk shaped magnetic rotating body 30 rotatable synchronously with rotation of the shaft 29 , a MR element 28 being arranged so as to face the periphery of the magnetic rotating body 30 with a predetermined spacing of gap facing the magnetic rotating body 30 , a magnet 31 for supplying the magnetic field to the GMR element 7 which is provided to the magnetic detection element 28 , and an integrated circuit 45 for processing the output of the GMR element 7 . Range of magnetic field to be detected by the GMR element 7 can be changed in many ways by adjusting amount of leakage magnetic flux of the magnet 31 , distance between the magnet 31 and the GMR element 7 and the distance between the magnetic rotating body 30 and the GMR element 7 . By adjusting those factors, the magnetic field to be detected is placed within a range of exceeding the field which is necessary to maximize the resistance value and of falling below the one which is obtained by multiplying the saturated magnetic field by 0.8.
As shown by FIG. 2, the magnetic detection element 28 consists of the GMR element 7 and an integrating circuit 45 , which are formed by means of lamination layers treatment technology on the front surface of a substrate 1 such as silicon substrate facing toward periphery of the magnetic rotating body 30 . The magnet 31 is mounted on the back face of this magnetic detection element 28 by unshown securing means. According to Embodiment 1 of the present invention, the detection element is operated in the magnetic field such that change of the magnetic field along the magnetic detection at the magnetosensitive face of the GMR element 7 provided on the front surface of the substrate of the magnetic detection element 28 stays in the range of exceeding the magnetic field for maximizing the resistance value of the GMR element 7 . Furthermore, the detection is preferably to be performed in a magnetic field which is below the one obtained by multiplying the saturation magnetic field of the GMR element 7 by 0.8, and any arrangement of those elements are acceptable only if conditions just mentioned above are satisfied: for example, as shown by FIG. 3, arrangements are made so that the surface of the GMR element 7 provided on the magnetic detection element 28 is placed nearly perpendicular to the uneven surface of recess and protrusion of the magnetic rotating body 30 and the magnet 31 is arranged immediately above (also possible to be immediately below) the GMR element 7 . In this case too, unshown integrated circuit is provided near the GMR element 7 .
When range of the magnetic field to be detected by the GMR element 7 is expanded to the region below the magnetic field smaller than field at Rmax, the hysteresis of the magnetic resistance curve in this range of the magnetic field increases; and this produces a disadvantage such that accuracy for detection of edges of the recess and protrusion of the rotating body 30 is reduced and sufficient output can not be obtained in the case where the magnetic field becomes extremely small only in a specific portion such as the space between recess and protrusion of the magnetic rotating body 30 facing the magnetic detection element 28 is partially narrowed.
Generally speaking, since the saturation magnetic fields of the GMR layer decreases as the temperature rises, as the case may be, it is may happen that the magnetic field obtained by multiplying the saturation magnetic field at a room temperature by 0.8 exceeds the saturation magnetic field as the temperature rises. The resistance change rate (%/Oe) in the vicinity of the saturation magnetic field at the room temperature is by nature limited only to a relatively small value, and as the temperature rises, the resistance change rate (%/Oe) further decreases. Because of dependency of output level on the resistance change (%/Oe), lowering of output advances. In this way, there may be a disadvantage such that lowering of output under the operation at high temperature becomes noticeable when the range of magnetic field to be detected by the GMR element 7 is expanded to a range larger than the field obtained by multiplying the saturation magnetic field of the GMR element 7 by 0.8.
The foregoing disadvantage can be overcome by operating the GMR element 7 in the range of magnetic field which exceeds the one at which the resistance value becomes maximum and falls below the one obtained by multiplying the saturation magnetic field of the GMR element 7 by 0.8, and thereby expansion of the range of working temperature and raising the sensitivity will be attained.
Thus, according to Embodiment 1 the detection is performed under the condition that the change of the magnetic field in the direction of detection at the magnetic sensitive face of the GMR element 7 provided on the magnetic field detection element 28 lies in the range which exceeds the field maximizing the resistance of the GMR element 7 and falls below the one obtained multiplying the saturation magnetic field of the GMR element 7 by 0.8 and thus the detection element having a wide range of working temperature and also having high detection sensitivity can be provided. Now, the lower limit below the field obtained by multiplying by 0.8 is described as follows: Suppose “the magnetic field multiplied by 0.81” is denoted provisionally by Hss, in view of lowering output at high temperature operation, the following relation of
−Hss≦H≦Hss
is deemed to be an effective range.
Embodiment 2
FIG. 4 shows relation between resistance change rate per unit magnetic field of the GMR element and the number of lamination layers according to Embodiment 2.
The GMR element 7 as above consists of an alternate successive laminated layers of Fe(x)Co(1−X)[≦x≦0.3] layer and upper layer and FIG. 4 shows the relation between the resistance change rate per unit magnetic field and the number of lamination in the case where, thickness of a single copper layer is chosen so that the magnetic resistance change reaches the vicinity of second peak at that thickness and a lamination consisting of a bundle of a single Fe(x)Co(1−X)[≦x≦0.31] layer and a single copper layer is counted as one lamination. A description will be given on the definition of “a bundle of”.
As shown by FIG. 4 a resistance change rate per unit magnetic field (hereinafter referred to as magnetic field sensitivity) takes large value near the lamination number of fifteen to thirty when Fe(x)Co(1−X)[ 0 ≦x≦0.3] is used as a magnetic layer and in order to have a sufficient detection sensitivity as an magnetic detection element around at 150° C. it is preferable to choose the lamination number from ten to forty. When the lamination number is less than ten or more than forty, a sufficient magnetic field sensitivity can not be obtained for any sample.
Thus in Embodiment 2, the GMR element 7 consists of laminated layers of alternate succession of Fe(x)Co(1−X)[ 0 ≦x≦−0.3] layer and upper layer, thickness of a single copper layer is chosen so that the magnetic resistance change with respect to this thickness takes the value in the vicinity of second peak and also the number of lamination of the Fe(x)Co(1−X)[ 0 ≦x≦0.3] layer and copper layer is chosen to be in the range of ten to forty. Therefore, in view of above reason, it is possible to improve the sensitivity of the magnetic detection element 28 .
Embodiment 3
FIG. 5 shows the resistance change rate per unit magnetic field of the GMR element with respect to thickness of the FeCo layer according to Embodiment 3.
FIG. 5 shows the relation of the resistance change rate per unit magnetic field with respect to the thickness of a single Fe0.1Co0.9 layer when the GMR element, which exhibits the best characteristics as shown by FIG. 4, consists of laminated layers of an alternate succession of Fe(x)Co(1−X)[x=0.1] layer and copper layer in which the magnetic resistance change with respect to the thickness of a single copper layer takes a value near the second peak.
The resistance change rate per unit magnetic field as shown by FIG. 5 rises suddenly from the thickness of near 10 Å and exhibits sufficiently large values from 12 Å to near 20 Å and beyond 30 Å sufficient magnetic field sensitivity can not be obtained.
Accordingly, it is preferable to form the GMR element 7 choosing the thickness of a single FeCo layer to be in a range of 10 Å to 30 Å.
As aforementioned in Embodiment 3, the GMR element consists of laminated layers of an alternate succession of a Fe(x)Co(1−x)[x≦0.3] and a copper layer and thickness of a Fe(x)Co(1−X)[≦x≦0.31] layer is chosen to be in range of 10 Å to 30 Å when thickness of a single copper layer is chosen so that the magnetic resistance change with respect to the thickness of copper layer becomes near the second peak. Therefore, in view of foregoing reason, it is possible to improve the sensitivity of the magnetic detection element 28 .
Embodiment 4
FIG. 6 and FIG. 7 show formation of layer of the GMR element according to the Embodiment 4 of the present invention.
As shown by FIG. 6, on the process of forming the layer 5 of the GMR element, for example, after the formation of the layer 9 a of FeCo layer on the surface of the base layer 2 such as thermal oxidation layer of silicone formed on the substrate 1 such as silicone substrate, Copper layer 10 , Fe(x)Co(1−X)[0≦x0.3] layer 9 , Cu layer 10 , FeCo layer 9 are successively formed on that FeCo layer 9 a . Paired layers of FeCo Layer 9 with Cu layer 10 is laminated ten times to forty times to end up with the upper most layer to be the FeCo layer 9 . Suppose that the uppermost layer is Co layer consisting of material having higher electric conductance than that of FeCo layer 9 , probability of flowing of electrons, which do not contribute to the GMR effect, through near the surface rises and as a result magnetic resistance change rate (MR rates) will be reduced; and thus the uppermost layer is preferably formed by FeCo layer 9 as shown by FIG. 6 .
As shown by FIG. 7, by successively forming further a SiNx layer as a protective layer on the uppermost layer of the FeCo layer 9 , the GMR element 5 is protected from oxidation during processes to be followed such as photolithographic process, thereby characteristics of element 7 can be stabilized. The SiNx layer as a protective layer can be formed successively without releasing the vacuum after the formation of the uppermost FeCo layer 9 ; in other words, by preparing laminated layers of GMR element layer 5 (laminated layers) by repetition of Fe(x)Co(1−X)[≦x≦0.3] layer 9 and Copper layer 10 and by forming the protective layer 8 on the uppermost layer of the GMR element layers 5 , production of GMR element can be made; after forming the uppermost layer by means of thin film technology such as spattering, low temperature plasma CVD and vacuum deposition, without releasing the vacuum the protective layer too can be formed by means of the thin film technology.
By virtue of this process, natural oxidation acted on the GMR element layers 5 can be suppressed and works effectively further on improvement of stabilization.
In place of SiNx layer, as protective layer, besides dielectric layers such as oxide Si layer and oxide Ta layer, metal layer of Ti, V, Ta, Nb, Zr, etc., combined metal layer of them, oxide layer and nitride layer of them can be used. Any of them can be formed by means of spattering, low temperature plasma CVD and vacuum deposition without detriment to the characteristics of the GMR element layers 5 .
In this way in Embodiment 4 of the present invention the upper most layer of the GMR element layers 5 is formed by FeCo layer 9 , and thus the magnetic characteristics of the GMR element 7 can be improved and also the reliability of the GMR element 7 can be improved by virtue of forming the protective layer 8 after formation of the GMR element layers 5 .
Now, descriptions will be given on the definition of term “a bundle of”. As to the layer of which the laminated layers are consisted as shown by FIG. 6 and FIG. 7, layer 9 and layer 10 are FeCo layer and Cu layer, respectively, and starting from the substrate 1 , in a succession of substrate 1 /foundation layer 2 /lowermost positioned FeCo layer 9 /[Cu layer 10 /FeCo layer 9 ]/[Cu layer 10 /FeCo layer 9 ]/[Cu layer 10 /F FeCo layer 9 ]/. . . [Cu layer 10 /FeCo layer 9 ], i.e. in the repetition of pained layer 90 of [Cu layer 10 /FeCo layer 9 ], the laminated layers are formed. The term “a bundle of” is meant by the paired layer 90 of Cu layer 10 /FeCo layer 91 . This paired layer also can be regarded as a paired layer other than the first occuring FeCo layer.
This laminated formation can be expressed briefly as lowermost FeCo layer 9 a /[Cu layer 10 /FeCo layer 9 ]×n (number of bundles is n), and this n is defined as the number of lamination.
In this instance, the lowermost layer FeCo 9 is not necessarily required and yet used because presence of this layer enable to proceed a stable production. Referring only to the formation of [Cu layer 10 /FeCo layer 9 ]×n, paired layer Cu 10 and FeCo 9 is called as “a bundle”.
Embodiment 5
FIG. 8 ( a ) and ( b ) are sectional views showing formation of layers when the GMR element 7 is configured to pattern according to the Embodiment 5 of the present invention.
The GMR element 7 is formed by configuring the GMR element 5 into a pattern consisting of n times laminations of the paired layer 90 . When this pattern formation of the GMR element 5 is proceeded, on the protective layer 8 formed on the GMR element 5 , pattern of the element is transcribed on to the resist by means of photolithography, perform etching using the ion beam etching IBE and finally remove the resist.
FIG. 8 ( a ) is a sectional view of the GMR element 7 in which the resist pattern is already removed after the etching with the zero incident angle of the ion beam with respect to the substrate 1 is already finished; in this instance, film 11 which is formed through re-adhering of the resist pattern to the side surface is left as a projection along longitudinal direction and this projection becomes an obstacle against final formation of the protection layer aiming protection of the side surface of the GMR layer 5 .
Contrary to the above instance, FIG. 8 ( b ) is a sectional view of the GMR element 7 in which the resist pattern is removed after etching by irradiation of ion beam with some angle with respect to the substrate 1 . In this case there exist no residue of re-adhered film 11 which appears in FIG. 8 ( a ) and also the side surface can be tapered and thus coverage in the process of final protective layer formation can be improved. In the case tapering with angle 12 of less than 20° or more than 80 ° will bear sufficient effect. But in view of accuracy of pattern width, or in the case where diminishing of pattern width or diminishing of pattern spacing is desired, the angle more than 40° is more preferable; and further the angle less than 65° is more preferable in view of mass production with regard to bring the probability of the residue of the re-adhered film 11 to almost zero.
In this way the pattern of the GMR element 7 of Embodiment 5 is provided with a cone angle 12 of more than 20° and less than 80° or more preferably an angle of more than 45° and less than 65°, and thus reliability of the GMR element 7 can be improved.
Though up to now descriptions are given on the formation of the GMR element 7 on the substrate 1 using lamination layer treatment technology, the GMR element 7 , which is already formed on a separate substrate, can be bonded on the substrate 1 by means of an adhesive, too.
According to the invention, since the magnetic detection element comprises a GMR element and this GMR element is operated in a magnetic field less than the one which is obtained by multiplying the saturation magnetic field by 0.8, the sensitivity of the magnetic detection element can be improved and also expansion of range of work temperature can be attained.
According to the invention, since the GMR element is operated in a magnetic field larger than the one for maximizing the resistance of the GMR element, the sensitivity can be improved further and the expansion of working temperature range can be attained.
According to the invention, since the magnetic detection element is provided on the laminated layers circuit, extra supporting members to support the integrated circuit is no longer required.
According to the invention, since the GMR clement consists of alternate succession of Fe(x)Co(1−X)[ 0 ≦x≦0.3] layer and Cu layer, thickness of Cu layer is chosen so that the magnetic resistance change with respect to the thickness of a single Cu layer takes near the second peak, and the number of lamination of layers lie in the range of more than 10 and less than 40 with a bundle of Fe(x)Co(1−X)[≦x≦0.3] layer and Cu layer being counted as one lamination, a magnetic detection element having a good magnetic characteristic and high detection sensitivity can be obtained.
According to the invention, since the thickness of the Fe(x)Co(1−X)[0≦x≦0.3] layer is more than 10 Åand less than 30 Å, a magnetic detection element having a good magnetic characteristic and a high sensitivity can be obtained.
According to the invention, since the uppermost layer is the Fe(x)Co(1−x)[0≦x≦0.3] layer, a GMR having a good magnetic characteristics can be obtained.
According to the invention, since a protective layer is formed on the uppermost layer of Fe(x)Co(1−X)[0≦x≦0.3], the reliability of the MR element can be improved.
According to the invention, since the side surface of the resistance pattern formed as the GMR element is tapered off with an angle of more than 20° and less than 80° with respect to surface of the substrate, the final protective layer can be formed in a stabilized manner and reliability of the magnetic detection element can be improved.
According to the invention, since the side surface of the resistance pattern formed as the GMR element is tapered off with an angle of more than 40° and less than 65° with respect to the surface of the substrate, the final protective layer can be formed in a further stabilized manner and reliability of the magnetic detection element can be further improved.
According to the invention, since after forming the lamination layer, the protective layer is formed without releasing the vacuum, reliability of the MR clement can be improved.
According to the invention, since the magnetic element consists of a magnetic rotating body having an uneven surface of recess and protrusion along its periphery and being rotatable on a shaft, a magnet being arranged facing the periphery of the magnetic rotating body and a magnetic detection element being provided at a position facing periphery of the magnetic rotary body, and also since the magnetic detection element consists of the aforementioned GMR element, it is possible to detect, in a wide temperature range for example from 40° C. to 150° C., change of the magnetic field between the magnetic rotating body and the magnet due to the rotation of the magnetic body and also since amount of rotation of the magnetic rotating body is detected on the basis of the result of detection, a magnetic detection clement having a high sensitivity and operable in a wide range of working temperature can be provided. | The present invention improves the sensitivity and expands the temperature range of operation of a magnetic detection device used in conjunction with rotary shafts such as those found in automobiles. A magnetic detection element consists of a giant magnetoresistance element and an integrated circuit for performing a predetermined operational processing based on the variation of magnetic field detected by the giant magnetoresistance element, and the magnetic detection element is operated in the magnetic field in the range of exceeding the magnetic field for maximizing the resistance value of the giant magnetoresistance element and below the field obtained by multiplying the saturation magnetic field of the giant magnetoresistance element by 0.8. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims priority to International Application No. PCT/JP2007/070401 which was filed on Oct. 19, 2007 and claims priority to Japanese Patent Application No. 2006-288848 filed on Oct. 24, 2006.
STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT
Not Applicable
BACKGROUND OF THE INVENTION
1. Technical Field of the Invention
The present invention relates to a method for removing lead from a cement burning furnace, and more particularly to a method for removing lead from a cement burning furnace by collecting lead from dust contained in a part of combustion gas that is extracted from a kiln exhaust gas passage running from the inlet end of the cement kiln to a bottom cyclone.
2. Description of the Related Art
It has been considered that since lead (Pb) contained in cement is immobilized, the lead does not elute to soil. However, with increased amounts of recycled resources utilized in a cement manufacturing device in recent years, lead contained in cement has been increasing to the extent that the content sharply exceeds the record in the past. Since there is a possibility that the lead elutes to soil due to the increased concentration, lead content of cement is required to be reduced to the previous record.
In order to reduce lead content of cement, for example, a method of treating waste is described in the first patent document. The method comprises the processes of: a washing process for washing waste; an alkali-eluting process for solid phase separated; a deleadification process for separating lead from the filtrate through precipitation; a decalciumization process for separating calcium through precipitation from the filtrate from which the lead is removed; and salt collecting process for separating and collecting salt by heating the filtrate through separation, to effectively separate and remove chlorine and lead in waste that is fed to a cement manufacturing process.
In addition, a method of treating waste is described in the second patent document. The method comprises the steps of: mixing waste with a solution containing calcium ion to produce slurry; solid-liquid separating the slurry to generate solid phase containing zinc and water solution containing lead; adding sulfurization agent to the water solution containing lead; and solid-liquid separating the water solution to produce lead sulfide and solution containing calcium ion, to separated and remove lead and the like from waste such as fly ash.
Patent document 1: Japanese Patent Publication No. 2003-1218 gazette
Patent document 2: Japanese Patent Publication No. 2003-201524 gazette
BRIEF SUMMARY OF THE INVENTION
Although, in the conventional art described in the above-mentioned patent documents, to reduce lead content, lead contained in the chlorine bypass dust, which is recovered from a part of combustion gas that is extracted from a kiln exhaust gas passage from an inlet end of a cement kiln and a bottom cyclone, is removed the ration of the lead, which is removed from the chlorine bypass dust and is discharged to the outside of the system, to total lead is only approximately 30%, so that even if lead contained in the chlorine bypass dust would completely be removed, remaining approximately 70% of lead would still be taken in clinker that is discharged from the cement kiln, therefore, it is not easy to reduce lead content of cement. Therefore, it is important to increase lead concentration of chlorine bypass dust and the like by accelerating lead volatilization in the cement kiln.
Chloridization-volatilization method and reduction-volatilization method are known as technology for lead volatilization. However, when generally performed chloridization-volatilization method is applied to a cement burning process, it is necessary to feed by far much amount of chlorine than practical amount in cement manufacturing. On the other hand, applying reduction-volatilization method causes color of the cement produced to be yellow-ish, resulting in a problem in quality of the cement.
The present invention has been made in consideration of the above-problems in the conventional art, and the object thereof is to provide a method for efficiently reducing lead content of cement by increasing lead concentration to the chlorine bypass dust and others.
To achieve the above object, a method for removing lead from a cement burning furnace according to the present invention is characterized by comprising the steps of: controlling O 2 concentration of combustion gas in an inlet end of a cement kiln to 5% or lower and/or CO concentration thereof 1000 ppm or more; extracting a part of combustion gas; and collecting lead from the dust collected.
With the present invention, it becomes possible to sharply increase lead volatilization rate by generating reduction atmosphere in the area where temperature of raw material in a cement kiln is between 800° C. and 1100° C., which is near the inlet end of the cement kiln. As a result, extracting a part of cement kiln combustion gas and collecting lead from dust that is collected from the combustion gas allows lead content of cement to efficiently be reduced. In addition, this method has no effect on the quality of the cement.
In the method for removing lead from a cement burning furnace described above, while controlling O 2 concentration of the combustion gas in the inlet end of the cement kiln 5% or lower and/or CO concentration thereof 1000 ppm or more, fuel and/or raw material including inflammable material can be fed to an area where L/D of the cement kiln is 0 or more and 12 or less, where an inner diameter of the cement kiln is D and a distance from the inlet end of the cement kiln longitudinally into the kiln is L. With this, it is possible to securely maintain reduction atmosphere in the area where temperature of raw material in a cement kiln is between 800° C. and 1100° C., which allows lead content of cement to further efficiently be reduced.
In the above method for removing lead from a cement burning furnace, powdery and/or slurry fuel and/or raw material including inflammable material may be injected with a nozzle to the area where L/D of the cement kiln is 0 or more and 12 or less.
Further, lump fuel and/or raw material including inflammable material can be fed with a long distance thrower to the area where L/D of the cement kiln is 0 or more and 12 or less.
Still further, it is possible to cylindrical or globular fuel and/or raw material including inflammable material is fed by utilizing an inclined surface of the inlet end of the cement kiln to the area where L/D of the cement kiln is 0 or more and 12 or less, and the cylindrical or globular fuel and/or raw material including inflammable material may be formed from small pieces of fuel and/or raw material including inflammable material.
The fuel and/or raw material including inflammable material can be fed from a port installed in the area where L/D of the cement kiln is 0 or more and 12 or less.
As mentioned above, with the method for removing lead from cement burning furnace according to the present invention, it becomes possible to efficiently reduce lead content of cement without effect on the quality of the cement.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1( a ), 1 ( b ), 1 ( c ) and 1 ( d ) are diagrammatical views exemplarily showing devices to carry out a method for removing lead from a cement burning furnace according to first, second, third and fourth embodiments of the present invention, respectively;
FIG. 2 is a flow chart showing overall construction of a chlorine bypass system attached to a cement burning furnace;
FIGS. 3( a ), 3 ( b ), 3 ( c ), 3 ( d ) and 3 ( e ) are a series of graphs showing the relation between gas temperature and lead volatilization rate calculated by chemical equilibrium simulation;
FIG. 4 is a graph showing the relation between inlet end CO concentration of a cement kiln and lead volatilization rate; and
FIG. 5 is a is a graph showing the relation between inlet end O 2 concentration of a cement kiln and lead volatilization rate.
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be explained with reference to figures.
FIG. 1( a ) shows an example of a device to carry out a method for removing lead from a cement burning furnace according to the first embodiment of the present invention, this device is provided with nozzle 1 , at an inlet end 10 a (at the end to which a calciner 11 and a bottom cyclone 12 are installed) of a cement kiln 10 , for injecting raw material including powdery and/or slurry fuel and/or raw material including inflammable material hereinafter referred to as “fuels” according to circumstances) into the cement kiln 10 .
The nozzle 1 is provided with a feeder not shown for feeding fuels F and an injector for injecting fuels F, which is fed to the nozzle 1 , into the cement kiln 10 . With this, fuels F can deeply be injected into the cement kiln 10 .
The nozzle 1 is provided with a feeder not shown for feeding fuels F and an injector for injecting fuels F, which is fed to the nozzle 1 , into the cement kiln 10 . With this, the fuels F can deeply be injected into the cement kiln 10 .
Meanwhile, as illustrated in FIG. 2 , the cement kiln 10 is provided with a chlorine bypass system, and gas extracted from a kiln exhaust gas passage, which runs from the inlet end of the cement kiln 10 to the bottom cyclone is cooled with cooling air from a cooling fan 22 in a probe 21 , and is introduced to a cyclone 23 so as to be divided into coarse powder dust, and fine powder and gas. The course powder dust is returned to a cement kiln system, and fine powder (chlorine bypass dust) including potassium chloride (KCI) and the like is collected by a dust collector 24 . Meanwhile, gas exhausted from the dust collector 24 is released to the atmosphere via an exhaust fan 25 .
Next, the method for removing lead from a cement burning furnace according to the present invention with the system described above will be explained.
In FIG. 1( a ), powdery or slurry fuel and/or raw material including inflammable material is injected into the cement kiln 10 with the nozzle 1 . Here, as fuels, besides fine coal and heavy oil, which are generally used as main fuels for the cement kiln 10 , various kinds of material such as waste fuels may be utilized. Further, as for raw material including inflammable material also, kinds of material are not limited, and recycled waste may be used. But, when fuels with much volatile matter are used, even if gas with strong reducing effect was generated, the gas would instantly flow downstream and was replaced with gas with oxidizing effect, so that fuels with much fixed carbon are preferably used.
With the nozzle 1 , the fuels F are injected to the area where L/D of the cement kiln 10 is 0 or more and 12 or less, where the inner diameter of the cement kiln is D and the distance from the inlet end 10 a of the cement kiln 10 longitudinally into the kiln 10 is L.
FIGS. 3( a ) to ( e ) show the relation between gas temperature and lead volatilization rate by chemical equilibrium simulation, the axis of abscissas shows gas temperature and the axis of ordinates shows lead volatilization rate. Further, in the FIGS. 3( a ) to ( e ), (a) shows moist air atmosphere, (b) standard combustion gas atmosphere, (c) no oxygen atmosphere, (d) low CO concentration atmosphere and (e) high CO concentration atmosphere, from (a) to (e), atmosphere gradually changes from oxidizing atmosphere to reducing atmosphere, and (e) shows the strongest reducing atmosphere.
As clearly shown n FIG. 3 , under the strong reducing atmosphere (e), lead volatilization rate sharply rises in the area where gas temperature is between 700° C. and 1200° C. in comparison with other cases. The above temperature area corresponds to the area near the inlet end 10 a of the cement kiln 10 . Therefore, to the area where L/D of the cement kiln 10 is 0 or more and 12 or less, that is, to the area where raw material temperature in the cement kiln 10 is between 800° C. and 1100° C., powdery or slurry fuels F are injected to change this area to reducing atmosphere, which allows lead volatilization rate to considerably be increased.
FIG. 4 gives examination data showing the relation between CO concentration in the inlet end 10 a of the cement kiln 10 (hereinafter referred to as “inlet end CO concentration”) and lead volatilization rate. When the inlet end CO concentration becomes 0.1% (1000 ppm) or more, the lead volatilization rate becomes approximately 90% or more, and when the inlet end CO concentration becomes 0.3% (3000 ppm) or more, the lead volatilization rate becomes approximately 95% or more. With this, it is substantiated that under strong reducing atmosphere lead volatilization rate considerably rises in the area near the inlet end 10 a of the cement kiln 10 shown in FIG. 1 .
In addition, FIG. 5 gives examination data showing the relation between O 2 concentration in the inlet end 10 a of the cement kiln 10 (hereinafter referred to as “inlet end O 2 concentration”) and lead volatilization rate. When the inlet end O 2 concentration becomes 5% or less, the lead volatilization rate becomes approximately 90% or more, and when the inlet end O 2 concentration becomes 3% or less, the lead volatilization rate becomes approximately 95% or more. With this also, it is substantiated under strong reducing atmosphere lead volatilization rate considerably rises in the area near the inlet end 10 a of the cement kiln 10 shown in the FIG. 1 .
Lead volatized in the cement kiln 10 is, in FIG. 2 , included in the gas extracted by the probe 21 ; the extracted gas is cooled in the probe 21 ; the extracted gas is introduced to the cyclone 23 and is separated into coarse powder dust, and fine powder and gas; and the fine powder is collected by the dust collector 24 . Since to the fine powder is concentrated much lead in comparison to conventional one as much lead is volatilized in the cement kiln 10 , lead content of the cement manufactured by the cement kiln 10 can be reduced by collecting the lead.
FIG. 1( b ) shows an example of a device to carry out a method for removing lead from a cement burning furnace according to the second embodiment of the present invention, this device is provided with a long distance thrower 2 , at the inlet end 10 a of the cement kiln 10 , for feeding lump fuels F into the cement kiln 10 . The long distance thrower 2 adopts elastic body, air pressure, oil pressure or the like as motive energy, and is constructed in such a manner that the fuels F supplied to the nozzle 1 are deeply fed into the cement kiln 10 .
With this long distance thrower 2 and so on, the fuels F are fed to the area where L/D of the cement kiln 10 is 0 or more and 12 or less, and like the first embodiment, the area where raw material temperature in the cement kiln 10 is between 800° and 1100° can be turned into reducing atmosphere to considerably increase lead volatilization rate. And, as described above, collecting lead from the chlorine bypass dust to which much lead is concentrated in comparison to conventional one allows lead content of the cement manufactured by the cement kiln 10 to be reduced.
Meanwhile, in this embodiment, condition of the injection such as dimension of the fuels F and initial velocity can be determined by calculation through fluid simulation or the like in consideration of fluid resistance R=C·A·ρ·u 2 /2, where C: resistance coefficient, A: projected area, ρ: density, u: relative velocity. This prevents the fuels F from returning on the kiln inlet 10 a side by exhaust gas of the cement kiln 10 , which allows the fuels F to securely be fed to the area where L/D of the cement kiln 10 is 0 or more and 12 or less with the long distance thrower 2 .
In addition, the position that the long distance thrower 2 is installed also, in order to prevent the returning of the fuels F, is preferably determined on raw material side on rear face of the cement kiln. The exhaust gas of the cement kiln does not uniformly flow in the kiln, but preferentially flows on the other side of raw material with low resistance. Therefore, at the feeding of the fuels F, installing the long distance thrower 2 on raw material side with low resistance prevents the returning of the fuels F.
FIG. 1( c ) is for explaining a method for removing lead from a cement burning furnace according to the third embodiment of the present invention. In this embodiment, cylindrical or globular fuels F are fed by utilizing an inclined surface 3 of the inlet end 10 a of the cement kiln 10 . By utilizing inertia of the cylindrical or globular fuels F rolling on the inclined surface 3 , the fuels F are deeply fed to the cement kiln 10 .
With the above method also, the fuels F are fed to the area where L/D of the cement kiln 10 is 0 or more and 12 or less, and like the above embodiments, the area where raw material temperature in the cement kiln 10 is between 800° and 1100° can be turned into reducing atmosphere to considerably increase lead volatilization rate, and collecting lead from the chlorine bypass dust to which much lead is concentrated allows lead content of the cement manufactured by the cement kiln 10 to be reduced.
Meanwhile, as for conditions at the feeding of the cylindrical or globular fuels F also, by estimating the position where the fuels F reach based on a vertical position where the fuels F are fed and time for complete burning of the fuels F in an electric furnace or the like that is measured in advance, it becomes possible to more accurately feed the fuels F to a target position in the cement kiln. And, to manufacture cylindrical or globular fuels F, small pieces of fuels may be formed.
FIG. 1( d ) shows an example of a device to carry out a method for removing lead from a cement burning furnace according to the fourth embodiment of the present invention, this device is provided with a feeding port 4 installed in the area where L/D of the cement kiln 10 is 0 or more and 12 or less, and a feeder not shown for feeding the fuels F to the feeding port 4 . The feeding port 4 is constructed such that the feeding port 4 opens when positioning above the cement kiln 10 only, and material seal or the like is conducted to minimize the quantity of cool air that is taken into the cement kiln 10 .
With the feeding port 4 described above, the fuels F are directly fed to the area where L/D of the cement kiln 10 is 0 or more and 12 or less, and like the above embodiments, the area where raw material temperature in the cement kiln 10 can be between 800 and 1100° is turned into reducing atmosphere to considerably increase lead volatilization rate, and collecting lead from the chlorine bypass dust to which much lead is concentrated allows lead content of the cement manufactured by the cement kiln 10 to be reduced.
Meanwhile, in the above embodiments, fuels are fed to the area where L/D of the cement kiln 10 is 0 or more and 12 or less to turn the area where raw material temperature in the cement kiln 10 is between 800° and 1100° into reducing atmosphere. However, without feeding fuels, tuning the above-mentioned area into reducing atmosphere allows lead volatilization rate to considerably be increased. In actual operation of the cement kiln 10 , in order to securely maintain reducing atmosphere in the above-mentioned area, it is preferable not only to control O2 concentration of combustion gas in the inlet end of 10 a of the cement kiln 10 to 5% or lower and/or CO concentration thereof 1000 ppm or more but to feed fuels in the area where L/D of the cement kiln 10 is 0 or more and 12 or less.
EXPLANATION OF SIGNALS
1 nozzle
2 long distance thrower
3 inclined surface
4 feeding port
10 cement kiln
10 a inlet end
11 calciner
12 bottom cyclone
21 probe
22 cooling fan
23 cyclone
24 dust collector
25 exhaust fan | A method to efficiently reduce lead content of cement without exerting influence upon quality of the cement. The method comprises the steps of: controlling O2 concentration of combustion gas in an inlet end of a cement kiln to 5% or lower and/or CO concentration thereof 1000 ppm or more; extracting a part of combustion gas from the cement kiln and collecting dust contained in the combustion gas; and collecting lead from the dust collected. With this, the area where raw material temperature in the cement kiln is between 800° and 1100° can be turned into reducing atmosphere to sharply increase volatilization rate of lead, and collection of lead from the dust allows lead content of cement to efficiently be reduced without exerting influence upon quality of the cement. | 8 |
CLAIM FOR PRIORITY
This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. §119 from an application for LOCKING APPARATUS OF COMPUTER SYSTEM USING USB HUB earlier filed in the Korean Industrial Property Office on the 12 th of July 1997, and there duly assigned Serial No. P97-32391 by that Office, a copy of which application is annexed hereto.
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates to a computer system using an universal serial bus (USB) hub and, more particularly, to a display monitor of a computer system having a screen locking switch for controlling information signal from an information input device such as a keyboard and a mouse, and for preventing computer programs from unwarranted interference.
2. Related Art
A general computer system includes a computer main unit (which may have built-in storage devices such as floppy disks, hard disks and CD-ROM), a keyboard and a monitor connected to the main computer unit. Other computer peripheral devices such as an input mouse, a printer, a scanner, a telephone, and an external modem may also be connected to the main computer unit. These peripheral devices are generally supplied with power when the computer main unit is provided with power, or supplied with power by operation of a separate power ON/OFF switch. When power is supplied, each peripheral device must be initialized and pre-heated before use. The power supply is consumed by the peripheral device until manual power termination regardless whether the peripheral device is in use or not.
CRT monitor which is widely used as a display device of the computer system processes information signal received from the computer system via a signal transmission cable and provides a visual display of the processed information signal on a screen. When there is no signal from the computer system, the monitor remains idle. For purposes of conserving power, the display of data image on the monitor may be blanked during the period of inactivity and re-displayed when the computer system becomes active, i.e., when an input device such as a keyboard is operated. In addition, a screen saver function may be provided by software to store current image data in a separate memory and provides a visual display of a screen saving image during the period of inactivity. However, the screen saving function is automatic and is carried out after a predetermined time of inactivity. The user cannot lock the screen at a specific time that s/he desires. As a result, error may be generated in the program due to continuous keyboard operation by other users.
SUMMARY OF THE INVENTION
Accordingly, it is therefore an object of the present invention to provide a computer system having a screen locking function for locking a screen precisely at a desired time in order to prevent programs from unwarranted interference.
It is also an object to provide a computer system with a screen locking switch conveniently located on a display monitor for permitting a user to lock a screen of the display monitor and disable operation of input devices such as a keyboard and mouse.
It is further an object to provide a computer system using a universal serial bus (USB) hub for power and data distribution to different peripheral devices with a screen locking switch located on a display monitor for controlling operation of input devices such as a keyboard and mouse.
It is yet an object to provide a computer system providing an on-screen visual display of a screen locking function to inform a user of the status of computer operation.
These and other objects of the present invention can be achieved by a computer system provided with a screen locking function which comprises a computer main unit; information input is devices electrically connected to said computer main unit for permitting a user to input information to the computer main unit for data processing operation; a display device for providing a visual display of information processed by the computer main unit; and a screen locking apparatus positioned on the display device, for permitting the user to manually disable operation of the information input devices temporarily.
In accordance with another aspect of the present invention, a computer system provided with a screen locking function may be constructed with a computer main unit, a universal serial bus hub electrical connected to the computer main unit serving as a central connection point for power and data distribution to information input devices and a display device; and a screen locking switch positioned on the display device, for permitting a user to manually lock a screen of the display device and disable operation of the information input devices via the universal serial bus (USB) hub.
The present invention is more specifically described in the following paragraphs by reference to the drawings attached only by way of example.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the present invention, and many of the attendant advantages thereof, will become readily apparent as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein:
FIG. 1 is a block diagram of a typical computer system with a keyboard and a display monitor;
FIG. 2 is a block diagram of a computer system using a universal serial bus (USB) hub for power distribution to peripheral devices;
FIG. 3 is a detailed circuit diagram of the universal serial bus (USB) hub as shown in FIG. 2;
FIG. 4 is a detailed circuit diagram of a display monitor;
FIG. 5 is a schematic view of a control panel of a display monitor constructed according to the principles of the present invention as a preferred embodiment;
FIG. 6 is a flowchart of a screen locking process according to the principles of the present invention; and
FIG. 7 is a schematic view of the display monitor illustrating execution of screen locking according to the principles of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings and particularly to FIG. 1, which illustrates an exemplary computer system comprising a computer main unit 1 and peripheral devices such as a keyboard 2 , a mouse, 3 and a display monitor 4 connected to the computer main unit 1 . Each respective peripheral device has a port available via unoccupied one of slots on the mother board of the computer main unit 1 . Typically, the user has to open the computer main unit 1 and insert an interface card in a corresponding slot on the mother board. On occasions the user must operate a switch, set a jumper or arrange the types of connectors such as serial or parallel appropriate for the peripheral devices. Each peripheral device is generally supplied with power when the computer main unit 1 is provided with power, or supplied with power by operation of a separate power ON/OFF switch. When power is supplied, each peripheral device must be initialized and pre-heated before use. The power supply is consumed by the peripheral device until manual power termination regardless whether the peripheral device is in use or not. For instance, a display monitor of either a cathode-ray tube or a liquid crystal display which is widely used to process information signal received from the computer system via a signal transmission cable and provide a visual display of the processed information signal on a screen, the display monitor generally remains idle, when there is no signal activity from the computer system. A screen blank function may be provided such that display of data image on the monitor is blanked during the period of inactivity and re-displayed when the computer system becomes active, i.e., when an input device such as a keyboard is operated. In addition, a screen saver function may be provided by software such that current image data is stored in a separate memory and a screen saving image is displayed on the screen during the period of inactivity. However, the screen saving function is automatic and is carried out after a predetermined time of inactivity. The user cannot lock the screen at a specific time that s/he desires. As a result, error may be generated in the program due to continuous keyboard operation by other users.
This type of error is augmented when the computer system uses a universal serial bus (USB) hub which serves as a central connection point of the computer system for power and data distribution to all peripheral devices in order to conveniently control power distribution over different peripheral devices. The universal serial bus (USB) hub is used to reduce the number of interface cards and slots available on the mother board of the main unit 1 of the computer system. The peripheral devices to be connected to the universal serial bus (USB) hub may include a telephone network, a modem, a printer, a microphone, a mouse, a scanner, a digital camera and so on. Simplicity and convenience are the major advantages of the USB hub. This is because the universal serial bus (USB) hub can sense the addition or removal of peripheral devices from the computer system without rebooting the system even when power is still activated, unlike the conventional built-in slots. In addition, the USB hub supports plug-and-play operations such that information relating to the source, e.g., driver software required for the respective peripheral devices or band width of the bus can be obtained automatically without intervention of the user.
The use of a universal serial bus (USB) hub 10 is shown in FIG. 2 for connecting all peripheral devices such as a display monitor 4 , a printer 5 , a scanner 6 and an external modem 7 to the computer main unit 1 of the computer system. The keyboard 2 and display monitor 4 may be connected directly the computer main unit 1 . The USB hub 10 allows the user to install all other peripheral devices or its related cards to the computer system without having to open the computer main unit 1 for interface cards installation. The USB hub 10 provides connections between the computer main unit 1 and up to 127 peripheral devices and supplies an operational voltage of only 5 volts to the respective peripheral devices without consuming a vast DC voltage. In addition, the USB hub 10 has a data transmission rate of 12 Mbit/sec sufficient that most peripheral devices of a large band width can have a tremendous capacity at a little expense relative to the cost for the current connector technique.
FIG. 3 illustrates a circuit diagram of the USB hub 10 for power distribution of a designated peripheral device such as a display monitor 4 . The USB hub 10 includes a USB control circuit 11 for controlling information transmission between the computer main unit 1 and peripheral devices using data and clock provided by the display monitor 4 , a DC-DC converter 12 for processing the power supplied from the display monitor 4 to provide operation power to USB control circuit 11 and down stream ports 14 , 15 and 16 respectively connected to peripheral devices 5 - 7 , and an over-current protection circuit 13 for detecting output current of DC-DC converter 12 to prevent damages due to over-current. The computer main unit 1 is constructed such that it supplies the USB control circuit 11 with an operational power of 5 volts and exchanges information and clocks mutually with the USB control circuit 11 .
As shown in FIG. 3, the power (14V) supplied from the display monitor 4 passes through DC-DC converter 12 , to be provided to USB control circuit 11 as its operation voltage (5V). The power (5V) from DC-DC converter 12 is supplied to USB control circuit 11 and to peripheral devices 5 - 7 through down stream ports 14 , 15 and 16 . The computer system is connected to up stream port of USB control circuit 11 . In this case, USB environment is set in the computer, and the computer main computer 1 automatically supports the USB control environment. When the computer peripheral devices 5 , 6 and 7 are connected to down stream ports 14 , 15 and 16 of USB hub 10 , the computer main unit 1 identifies the ID and, if acceptable, installs the peripheral devices 5 - 7 automatically without separate action of the user.
Display monitor 4 processes information signal received from the computer main unit 1 via a signal transmission cable and provides a visual display of the processed information signal on a screen. An internal circuit of the display monitor 4 is shown in FIG. 4 .
Referring to FIG. 4, the computer main unit 100 includes a central processing unit (CPU) 110 for receiving an input keyboard signal, processing the input signal, and generating image data, and a video card 120 for receiving the image data from CPU 110 , processing the same as a video signal (R,G,B), and generating horizontal and vertical synchronous H-SYNC and V-SYNC signals for synchronizing the video signal. The video signal (R,G,B) and horizontal and vertical synchronous H-SYNC and V-SYNC signals are sent from video card 120 of the computer main unit 100 to the monitor 200 through a video signal cable (not shown).
Display monitor 200 receives the video signal and the horizontal and vertical synchronous H-SYNC and V-SYNC signals from the video card 120 of the computer main unit 100 . The display monitor 200 is composed of a microcomputer 210 which receives the horizontal and vertical synchronous signals, a control button section 220 for generating a screen control signal, a horizontal and vertical output circuit 230 for formulating an image, a video circuit section 240 for processing the video signal received from the video card 120 through amplification, and a power supply circuit 250 for supplying a driving power to the microcomputer 210 , the horizontal and vertical output circuit 230 , and the video circuit section 240 .
Microcomputer 210 which stores all sorts of screen control data is receptive to the horizontal and vertical synchronous H-SYNC and V-SYNC signals from the video card 120 , and generates an image adjusting signal and a reference oscillating signal in response to the screen control signal applied from the control button section 220 . A horizontal/vertical oscillation signal processor 231 receives the image adjusting signal and the reference oscillating signal from the microcomputer 210 , and supplies a vertical pulse to a vertical drive circuit 232 . The vertical pulse is used to control the switching rate, of a sawtooth wave generating circuit in response to the horizontal and vertical synchronous H-SYNC and V-SYNC signals.
The video drive circuit 232 can be either a one-stage vertical amplification type or an emitter follower type. The emitter follower type vertical drive circuit has the base of transistor used as an input with the emitter as an output. Hence the vertical drive circuit 232 normally has improved linear characteristic but not gain. The vertical drive circuit 232 , after amplification, supplies a drive current to a vertical output circuit 233 , which will apply a sawtooth current corresponding to a vertical synchronous V-SYNC pulse flowing through a V-DY, determining a vertical scanning period depending on the sawtooth current. In addition, a horizontal drive circuit 234 receives a horizontal oscillating signal from the horizontal and vertical oscillating processor 231 , and accordingly, supplies a drive current high enough to switch the horizontal output circuit 235 .
Upon receipt of the drive current from the horizontal drive circuit 234 , the horizontal output circuit 235 will generate a sawtooth current to the H-DY, determining a horizontal scanning period depending on the sawtooth current. Such a horizontal drive circuit 234 is divided into two classes; in-phase type whose output is ON with the drive terminal ON, and out-of-phase type wherein the output is OFF with the drive terminal ON.
High-voltage circuit 236 and FBT (flyback Transformer) 237 generate a high voltage in order to supply a stable DC voltage to the anode terminal 244 a of a cathode-ray tube (CRT) 244 . Even when a collector pulse is very weak, high-voltage circuit 235 and FBT 237 can generate a high voltage by use of a harmonic wave due to inductance and distribution capacity. This high voltage is applied to the anode terminal 244 a of the CRT 244 , forming a high voltage across the anodic surface of the CRT 244 . Simultaneously, the video circuit section 240 has an on-screen display (OSD) IC 241 which receives OSD data generated during the screen control of the microcomputer 210 to generate an OSD gain signal. This OSD gain signal from the OSD IC 241 is sent to a video pre-amplifier 242 .
Upon receipt of the OSD gain signal from the OSD IC 241 and the RGB video signal from the video card 120 , the video pre-amplifier 242 amplifies the RGB picture signals to a limited voltage level via a low-voltage amplifier. For example, a video signal less than 1 V pp is converted to the voltage of 4 to 6 V pp through an amplification in the video pre-amplifier 242 . This video signal is further amplified to 40 and 60 V pp in a video output amplifier 243 and then sent to the cathode of the CRT 244 for a visual display of a variable video image. The image which has been produced through the CRT 244 in response to the RGB video signal and the OSD signal has its scanning period determined by the H-DY and V-DY and is visually displayed on the screen of CRT 244 . The RGB video signal or the OSD signal which are amplified by the vide output amplifier 243 will be displayed as a variable video image with the luminance regulated by the high voltage formed across the anode surface of CRT 244 .
Power supplying circuit section 250 , which is to provide a driving voltage for displaying the RGB video signal on the screen of the display monitor, receives an AC (Alternative Current) through an AC input 251 . The AC is applied to a degaussing coil 252 , which resumes the color blotted due to the influence of the earth magnetic field or external environment to the original distinct one. For this, degaussing coil 252 disperses the magnetic field of a DC component formed across the shadow mask in CRT 244 while an AC is applied to the degaussing coil 252 momentarily for 2-8 seconds, and prevents the electron beams from being deflected unstably due to the magnetic field. The AC is normally rectified into a DC through a rectifier 251 and transmitted to a switching transformer 254 . The switching transformer 254 supplies all sorts of driving voltage required in the monitor 200 via a voltage regulator 255 . At this stage, PWM (Pulse Width Modulation) IC 256 controls the switching operation of the switching transformer 254 , stabilizing the output voltage of the transformer.
Microcomputer 210 which is in a DPMS (Display Power Management Signaling) mode to economize power consumed in the display monitor 200 , sets up a power-off mode and a suspend mode depending on the presence of horizontal and vertical synchronous H-SYNC and V-SYNC signals, and accordingly saves the power in the display monitor 200 . If the user adjusts a screen or wants to have information about the display mode of the display monitor which is in a current use, s/he has to choose the OSD function through the control button section 220 as programmed in the microcomputer 210 . Upon the user's pressing a button for the OSD function, the microcomputer 210 serves the OSD function in response to a key signal through the OSD IC 241 . In this case, the microcomputer 210 sends OSD data already stored therein to the OSD IC 241 , which processes the OSD data to generate an OSD gain signal to the video pre-amplifier 242 and the video output amplifier 243 . The OSD gain signal is then displayed on the screen of the CRT 244 after amplification via those amplifiers 242 and 243 . Under the OSD signal, the CRT 244 provides an on-screen display of menus relating to the OSD function. The user may choose one menu containing information ofthe display monitor 200 , such as screen locking, screen adjustment, display mode, horizontal and vertical frequencies, and the like.
Control button section 220 , as shown in FIG. 5, includes a variety of picture control buttons which are left/right position control key 221 , top/bottom position control key 222 , left/right size control key 223 , top/bottom size control key 224 and side pincushion control key 225 . While a certain control key is pushed, a minus control key and plus control key 226 are used to realize a picture in a required form. In addition those keys, the control button section of the display monitor according to the present invention also includes a screen locking switch 227 which operates in a toggle manner and maintains its setting state by repeating ON/OFF states. The screen locking switch 227 is configured to permit the user to manually lock the screen of the display monitor anytime, anywhere at any situation without having to wait for the screen saving function or the like in order to protect the programs which is currently executed, from potential interference or damage.
Now the operation of screen locking function provided by the screen locking switch 229 will be described in detail with reference to FIGS. 1, 4 and 6 as follows.
First of all, the user pushes the screen locking switch 227 on the control panel of the display monitor 200 at step S 10 . Here, the microcomputer 210 of the display monitor 200 confirms if a screen locking flag is set or not at step S 20 . When the screen locking switch is pushed while the screen locking flag is set, the microcomputer 210 of the display monitor 200 enables operation of information input devices such as a keyboard 2 and mouse 3 through the universal serial bus (USB) hub 10 at step S 31 . Then, the screen locking flag is reset at step S 41 . When the screen locking switch is pushed while the screen locking flag is not set, the microcomputer 210 of the display monitor 260 disables operation of the information input devices such as the keyboard 2 and mouse 3 at step S 32 . When the screen locking flag is set at step S 42 , OSD characters are displayed on the display monitor at step S 50 , as shown in FIG. 7, to inform the user that the screen locking has been carried out. Meantime, during execution of screen locking, the microcomputer 210 of the display monitor 200 outputs a control signal to realize the DPMS mode immediately. After setting of screen locking switch; transition from stand-by mode to suspend mode to power-off mode is performed with the lapse of time. Here, the operations of the information input devices such as the keyboard and mouse are controlled depending on whether the screen locking switch is set or not.
As described above, the present invention allows the user to control the keyboard and mouse in the computer system which can exchange information with them using the USB hub. Furthermore, when the user has to leave the system during execution of important program, the program can be prevented from being damaged by others.
While there have been illustrated and described what are considered to be preferred embodiments of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made, and equivalents may be substituted for elements thereof without departing from the true scope of the screen locking function of a computer system using USB hub of the present invention. In addition, many modifications may be made to adapt a particular situation to the teaching of the present invention without departing from the central scope thereof. Therefore, it is intended that the present invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out the present invention, but that the present invention includes all embodiments falling within the scope of the appended claims. | A computer system using a universal serial bus (USB) hub is provided with a screen locking function. The computer system includes a computer main unit, information input devices electrically connected to the computer main unit for permitting a user to input information to the computer main unit for data processing operation, a display device electrically connected to the computer main unit for providing a visual display of information processed by the computer main unit, and a universal serial bus (USB) hub arranged to electrically connect the information input devices and the display device to the computer main unit and through which, the screen locking apparatus is set to disable operation of the information input devices such as a keyboard and mouse. This way when the user temporarily leave the computer system, a currently executed program is protected from interference and damage. | 6 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a torque-transmitting device, and more particularly, to a torque-transmitting device using a lever, which can increase torque using the principle of the lever.
[0002] In general, levers have been widely used in various fields in modern society because the levers have a merit that they can gain a greater force with a small force in such a fashion that a bar turns on a predetermined position when a user applies force to an end portion of the bar.
[0003] Such levers have the fulcrum formed at the center of the turning lever, the force point where force is applied, and the point of action of the force applied at the end portion of the bar to an object.
[0004] The levers are classified into a first class lever in which the fulcrum is located between the force point and the point of action, a second class lever in which the point of action is located between the fulcrum and the force point, and a third class lever in which the force point is located between the fulcrum and the point of action.
[0005] An efficiency of force using the lever is decided depending upon a ratio of a magnitude of force, which is applied to the force point, to an operation distance of the bar and a ratio of a distance between the fulcrum and the point of force to a distance between the fulcrum and the point of action.
[0006] In order to apply force to an object using the principle of the lever, a linear directional force is applied to an end portion of the bar to move the position of the force point, and then, the position of the bar corresponding to the point of action is also changed and at the same time, the movement distance of the bar is also reduced, and hence, at the point of action, the lever can produce a greater force than the force applied to the force point.
[0007] Such a principle of the lever has been used through various types of modification in daily life and in industrial sites, but has not yet been used for a purpose to generate a strong torque at an output side by transmitting torque and amplifying torque.
SUMMARY OF THE INVENTION
[0008] Accordingly, the present invention has been made in an effort to solve the above-mentioned problems occurring in the prior arts, and it is an object of the present invention to provide a torque-transmitting device, which can convert torque input at one end portion of a lever into a greater force at the other end portion of the lever using the principle of lever to thereby gain a great rate of production.
[0009] To achieve the above objects, the present invention provides a torque-transmitting device including: a driving motor; a first mounting part having a driving rotor rotatably mounted, the driving rotor rotating by receiving a driving force from the driving motor; a second mounting part spaced apart from the first mounting part at a predetermined interval; a lever rotatably fixed on a support member disposed between the first mounting part and the second mounting part, the lever having one end portion mounted on the first mounting part and being rotated by the driving motor and the other end portion rotatably mounted on the second mounting part; an actuator connected with the other end portion of the lever in such a fashion as to do a rectilinear reciprocating motion as the lever rotates vertically; and a torque device adapted for converting the rectilinear reciprocating motion of the actuator into a rotary motion to thereby generate torque to operate a predetermined loaded device.
[0010] Moreover, preferably, the torque device includes: a first clutch that drivingly rotates relative to the rectilinear motion of the actuator in one direction but idly rotates relative to the rectilinear motion of the actuator in the opposite direction; and a second clutch that idly rotates relative to the rectilinear motion of the actuator in one direction but drivingly rotates relative to the rectilinear motion of the actuator in the opposite direction.
[0011] Furthermore, it is preferable that the torque device further includes: a first shaft rotating as a main shaft of the first clutch and providing a driving force to a loaded device; and a second shaft rotating as a main shaft of the second clutch and generating torque to be transmitted to the first shaft.
[0012] Additionally, the torque device further includes: a first driving gear rotatably connected to the first shaft; a second driving gear rotatably connected to the second shaft; and a connection member connected to the first driving gear and the second driving gear in such a fashion that the first driving gear and the second driving gear transmit the driving force mutually to rotate in the same direction, the connection member transmitting the torque of the second shaft to the first shaft.
[0013] In addition, the actuator includes: a first rack gear part that is disposed on one side of the actuator in such a way as to interlock the first clutch, the first rack gear part drivingly or idly rotating the first clutch according to a rectilinear reciprocating motion; and a second rack gear part that is disposed on the other side of the actuator in such a way as to interlock the second clutch, the second rack gear part drivingly or idly rotating the second clutch according to a rectilinear reciprocating motion.
[0014] Moreover, the torque-transmitting device further includes: laterally movable roller units respectively disposed at one end portion and the other end portion of the lever and moving in a lateral direction when the lever is rotated to thereby guide a motion of the lever; and vertically movable roller units mounted on the same axis as the laterally movable roller units and moving in a vertical direction when the lever is rotated to thereby guide the motion of the lever.
[0015] Furthermore, each of the laterally movable roller units and the vertically movable roller units includes: a first plate; a second plate spaced apart from the first plate at a predetermined interval and opposed to the first plate; and a plurality of rollers disposed between the first plate and the second plate, respectively rotatably mounted on a plurality of rotary centers, which are spaced apart from each other at predetermined intervals and arranged in parallel, the rollers protruding to one side and the other side of the first plate and the second plate.
[0016] The torque-transmitting device according to the present invention can convert torque input at one end portion of a lever into a greater force at the other end portion of the lever using the principle of lever to thereby gain a great rate of production.
BRIEF DESCRIPTION OF DRAWINGS
[0017] FIG. 1 is a perspective view of a torque-transmitting device according to a first preferred embodiment of the present invention.
[0018] FIG. 2 is a perspective view concretely showing hidden parts of the torque-transmitting device of FIG. 1 , from which some parts of the torque-transmitting device are omitted.
[0019] FIG. 3 is an exploded perspective view concretely showing a lever and the torque-transmitting device of FIG. 1 .
[0020] FIGS. 4 and 5 are views showing operations of the torque-transmitting device of FIG. 1 , wherein FIG. 4 illustrates an operation when one end portion of the lever goes down and FIG. 5 illustrates an operation of the torque-transmitting device in the condition of FIG. 4 .
[0021] FIG. 6 is a view showing an operation of the torque-transmitting device of FIG. 1 when the end portion of the lever goes up.
[0022] FIG. 7 is a view showing an operation of the torque-transmitting device in the condition illustrated in FIG. 6 .
[0023] FIG. 8 is a perspective view of a torque-transmitting device according to a second preferred embodiment of the present invention.
[0024] FIG. 9 is a perspective view showing configurations of a first torque-transmitting device and a second torque-transmitting device illustrated in FIG. 8 .
[0025] FIG. 10 is a view showing an operation of the torque-transmitting device of FIG. 1 .
[0026] FIG. 11 is a view showing an operation of the torque-transmitting device in the condition illustrated in FIG. 10 .
[0027] FIG. 12 is a view showing another operation of the torque-transmitting device according to the first preferred embodiment of FIG. 1 .
[0028] FIG. 13 is a view showing an operation of the torque-transmitting device in the condition illustrated in FIG. 12 .
DETAILED DESCRIPTION OF THE INVENTION
[0029] Reference will be now made in detail to the preferred embodiment of the present invention with reference to the attached drawings.
[0030] First, referring to FIGS. 1 and 2 , the entire configuration of a torque-transmitting device according to a first preferred embodiment of the present invention will be described in brief.
[0031] As shown in FIGS. 1 and 2 , the torque-transmitting device according to the present invention includes a driving motor 100 , a driving rotor 220 , a slave rotor 200 , a lever 300 , a first mounting part 400 , a second mounting part 500 , and a torque-transmitting device 300 .
[0032] The first mounting part 400 is a part where one end portion of the lever 300 to which force is inputted is located, and includes first main support rods 410 and first vertically moving rods 420 .
[0033] Two first main support rods 410 are spaced apart from each other at a predetermined interval and face each other.
[0034] Moreover, the first main support rods 410 includes: a driving connection shaft 411 to which the driving rotor 220 is connected; and a slave connection shaft 412 to which the slave rotor 200 is connected. In this instance, the driving rotor 220 and the slave rotor 200 are connected with each other by a belt or a chain B to thereby transmit driving power.
[0035] The first vertically moving rods 420 , to which one end portion of the lever 300 is connected, are mounted on the first main support rods 410 . Two first vertically moving rods 420 in a pair are in a bar shape like the first main support rods 410 and face with each other at a predetermined interval.
[0036] Each of the first vertically moving rods 420 includes a first guide rail 421 formed on the inner face thereof along a longitudinal direction. The first guide rail 421 is adapted to guide the end portion of the lever 300 to do a vertical movement smoothly.
[0037] A fixing plate 2 is joined to upper faces of the first main support rods 410 and the first vertically moving rods 420 in such a way as to fix the positions of the first main support rods 410 and the first vertically moving rods 420 .
[0038] The driving motor 100 is connected with the driving connection shaft 411 by a connection belt 470 , and the driving power transferred from the driving motor 100 is transferred to the driving connection shaft 411 . The driving connection shaft 411 rotates the driving rotor 220 and vertically moves the end portion of the lever 300 while the slave rotor 200 is rotated by the belt or chain B.
[0039] In this instance, as shown in FIG. 2 , driving rods 700 are fixed and disposed at the end portion of the lever 300 and the slave rotor 200 , and one end portion of the driving rod 700 is eccentrically fixed to the slave rotor 200 in such a fashion as to be rotatably connected in an eccentric state, and the other end portion of the driving rotor 700 is fixed at the end portion of the lever 300 .
[0040] In the meanwhile, a fulcrum 800 of the lever 300 is rotatably fixed on a support member 501 mounted between the first mounting part 400 and the second mounting part 500 .
[0041] It is preferable that a distance between the support member 501 and the first mounting part 400 is longer than a distance between the support member 501 and the second mounting part 500 and a distance between one end portion of the lever 300 and the fulcrum 800 is longer than a distance between the fulcrum 800 and the other end portion of the lever 300 . Moreover, the magnitude of force applied to the other end portion of the lever 300 can be controlled by adjusting the ratio of the distances.
[0042] Furthermore, second main support rods 510 are mounted on the second mounting part 500 to support the other end portion of the lever 300 . In this instance, it is preferable that the other end portion of the lever 300 is supported by the second main support rods 510 while guiding vertically moving parts.
[0043] Additionally, a torque device 900 connected with the other end portion of the lever 300 is installed on the second mounting part 500 , and will be described in detail later.
[0044] In the meantime, referring to FIG. 3 , the lever 300 and peripheral units used for the torque device 900 according to the first preferred embodiment of the present invention will be described in more detail.
[0045] As shown in FIG. 3 , the lever 300 of a single body is illustrated in the drawings, but it is not restricted to the drawings and levers of various forms, for instance, a lever, which is made by two parts combined with each other, may be also used.
[0046] First guide rods 330 are joined to upper and lower faces of the one end portion of the lever 300 , and each of the first guide rods 330 is formed to extend from a first lever 310 to one side, so that a first space portion 332 is formed between the first guide rods 330 . Moreover, a first blocking plate 333 is mounted at one end portion of each first guide rod 330 to thereby block the side of the first space portion 332 .
[0047] In this instance, a first auxiliary guide rail 334 is formed on the inner face of each first guide rod 330 , a first laterally movable roller unit 340 is inserted and mounted in the first space portion 332 between the first guide rods 330 , and upper and lower rollers of the first laterally movable roller unit 340 are seated on the first auxiliary guide rail 334 of the first guide rod 330 .
[0048] Moreover, the first laterally movable roller unit 340 has a through hole formed at the center thereof, and a penetration shaft 350 is inserted into the through hole. Furthermore, first vertically movable roller units 360 for guiding a vertical movement of the first lever 310 are respectively mounted on both ends of the penetration shaft 350 .
[0049] As shown in FIG. 2 , the right and left rollers of the first vertically movable roller units 360 are respectively seated and connected onto the first guide rails 421 of the first vertically moving rods 420 .
[0050] Meanwhile, second guide rods 330 A are respectively mounted on upper and lower faces of the other end portion of the lever 300 . A second space 332 A is formed between the second guide rods 330 A and a second blocking plate 333 A is joined to one side to thereby block the side.
[0051] In addition, a second auxiliary guide rail 334 A is formed on the inner face of the second guide rod 330 A and second laterally movable roller units 340 A are mounted inside a second space portion 332 A, and hence, the upper and lower rollers are seated on the second auxiliary guide rail 334 A. In this instance, it is preferable that the second laterally movable roller units 340 A have the same structure as the first laterally movable roller units 340 .
[0052] Moreover, a second penetration shaft 350 A is mounted at the center of the second auxiliary guide rail 334 a, and second vertically movable roller units 360 A are mounted at both ends of the second penetration shaft 350 A. It is preferable that the second vertically movable roller units 360 A have the same structure as the first vertically movable roller units 360 .
[0053] Therefore, when the lever 300 rotates around the fulcrum 800 , the laterally movable roller units 340 and 340 A guide the motion of the lever 300 while moving in a lateral direction, and the vertically movable roller units 360 , 360 A guide the motion of the lever 300 while moving in a vertical direction, so that the lever 300 can minimize friction force and smoothly work without overload.
[0054] Now, concrete structures of the laterally movable roller units or the vertically movable roller units (hereinafter, called “roller unit”) will be described in detail.
[0055] The roller units include a first plate P 1 , a second plate P 2 , and four rollers R 1 , R 2 , R 3 and R 4 , which are disposed between the first plate P 1 and the second plate P 2 .
[0056] The first plate P 1 and the second plate P 2 are spaced apart from each other at a predetermined interval and are faced with each other.
[0057] The first plate P 1 (or the second plate P 2 ) includes: rotary centers S 1 , S 2 , S 3 and S 4 that are formed on the inner face thereof in parallel and spaced apart from each other at predetermined intervals; and rollers R 1 , R 2 , R 3 and R 4 respectively rotatably mounted on the rotary centers S 2 , S 2 , S 3 and S 4 .
[0058] The rollers R 1 , R 2 , R 3 and R 4 respectively protrude toward one end side and the other end side of the first plate P 1 and the second plate P 2 , and the protruding roller portions rotatably move along the guide rail.
[0059] In the meantime, FIG. 3 shows an exploded perspective view of the torque device 900 as shown in FIGS. 1 and 2 . Referring to FIG. 3 , the torque device 900 of the first preferred embodiment illustrated in FIGS. 1 and 2 will be described in more detail.
[0060] A connection part 710 that is perforated by the second penetration shaft 350 A and vertically moves along the motion of the other end portion of the lever 300 is disposed at the other end portion of the lever 300 . For your convenience, the connection part 710 is in a cut form in FIG. 3 , but preferably, the connection part 710 may have an integrated form and be rotatably fixed at the other end portion of the lever 300 by the second penetration shaft 350 A.
[0061] It is preferable that an actuator 910 is disposed on one side of the connection part 710 and a guide bar 722 is disposed on the other side of the connection part 710 . In FIG. 3 , the actuator 910 is located below the connection part 710 and the guide bar 722 is located above the connection part 710 , and vice versa.
[0062] The connection part 710 shows a rectilinear motion in a vertical direction as the lever 300 rotates around the fulcrum 800 .
[0063] In this instance, because the connection part 710 is mounted rotatably on the second penetration shaft 350 A, the lever 300 can move in the vertical direction even though it rotates around the fulcrum 800 .
[0064] The guide bar 722 is inserted into a guide hole 3 to guide a vertically rectilinear motion of the connection part 710 , and the actuator 910 disposed on one side of the connection part 710 is also guided by the first and second clutches 921 and 932 to do the rectilinear motion.
[0065] Meanwhile, as shown in FIGS. 1 to 3 , the first clutch 921 and the second clutch 932 are respectively located on one side and the other side of the actuator 910 . In this instance, the first clutch 921 drivingly rotates relative to a downward rectilinear motion of the actuator 910 and idles relative to an upward rectilinear motion, on the contrary to the above, the second clutch 932 idles relative to the downward rectilinear motion of the actuator 910 and drivingly rotates relative to the upward rectilinear motion.
[0066] A first rack gear part (not shown in the drawings, opposed to a second rack gear part of the actuator 910 in FIG. 3 ) is disposed on a corresponding face to the first clutch 921 of the actuator 910 and interlocks the first clutch 921 . Additionally, a second rack gear part 912 is disposed on a corresponding face to the second clutch 932 and interlocks the second clutch 932 .
[0067] Furthermore, as shown in FIGS. 1 to 3 , the torque device 900 includes: a first shaft 920 adapted for providing a driving force to a loaded device while rotating as the central shaft of the first clutch 921 ; and a second shaft 930 adapted for generating torque, which will be transferred to the first shaft 920 , while rotating as the central shaft of the second clutch 932 .
[0068] When the actuator 910 descends, the first clutch 921 rotates the first shaft 920 while drivingly rotating (which is a contrary concept of idle rotation and is a driving force to drive the loaded device), and in this instance, the second clutch 932 rotates in the opposite direction of the first clutch 921 but idly rotates without any rotation of the second shaft 930 .
[0069] When the actuator 910 ascends, the second cultch 932 rotates the second shaft 930 while drivingly rotating, and in this instance, the first clutch 921 rotates in the opposite direction of the second clutch 932 but idly rotates without any rotation of the first shaft 920 .
[0070] In the meantime, a first driving gear 941 is rotatably connected to the first shaft 920 and a second driving gear 952 is rotatably connected to the second shaft 930 .
[0071] Furthermore, the first driving gear 941 and the second driving gear 952 are connected with each other by a connection member 960 , so that the second driving gear 952 can be rotated by the connection member 960 when the first driving gear 941 is rotated and the first driving gear 941 is rotated by the connection member 960 when the second driving gear 952 is rotated.
[0072] Accordingly, due to the connection member 960 , the first driving gear 941 and the second driving gear 952 can be rotated in the same direction while transmitting driving force to each other.
[0073] As shown in FIG. 3 , the connection member 960 may be a timing belt having a toothed structure that can be teeth-coupled with toothed structures of the first driving gear 941 and the second driving gear 952 .
[0074] Hereinafter, referring to FIGS. 4 to 7 , an operation of the torque-transmitting device according to the present invention will be described.
[0075] FIGS. 4 and 5 illustrate the operation of the torque-transmitting device according to the preferred embodiment of the present invention of FIG. 1 , wherein FIG. 4 shows an operation when the other end portion of the lever descends and FIG. 5 shows an operation of the torque-transmitting device in the condition of FIG. 4 .
[0076] Additionally, FIG. 6 shows an operation when the other end portion of the lever ascends in the torque-transmitting device illustrated in FIG. 1 , and FIG. 7 shows an operation of the torque-transmitting device in the condition of FIG. 6 .
[0077] First, as shown in FIG. 4 , when the driving motor is operated and rotates the slave rotor 200 , the driving rod 700 which is eccentrically fixed to the slave rotor 200 moves in such a way as to move one end portion of the lever 300 in the upward and downward directions.
[0078] In this instance, the vertically movable roller units and the laterally movable roller units are moved along the guide rail and the auxiliary guide rail to thereby make the vertical rectilinear reciprocating motion of the lever 300 smoother, and because it is previously described, it will be omitted.
[0079] When one end portion of the lever 300 ascends higher than the fulcrum 800 while the slave rotor 200 rotates, the other end portion of the lever 300 descends.
[0080] In this instance, the actuator 910 disposed on the first connection part 710 connected to the other end portion of the lever 300 is also descended, and the actuator 910 descends and drivingly rotates the first clutch 921 (see a part indicated by a dotted arrow in the drawing) and idles the second clutch 932 . (The second clutch 932 rotates in the opposite direction of the first clutch 921 but idly rotates)
[0081] In this instance, a first rack gear part 911 of the actuator 910 can convert the rectilinear motion of the actuator 910 into a rotary motion because the first rack gear part 911 interlocks the first clutch 921 .
[0082] While the first clutch 921 drivingly rotates, the first shaft 920 is rotated and the first driving gear 941 is also rotated by the rotation of the first shaft 920 .
[0083] While the first driving gear 941 is rotated, the connection member 960 is also rotated and the second driving gear 952 is also rotated in the same direction as the first driving gear 941 by the connection member 960 . Moreover, while the second driving gear 952 rotates, the second shaft 930 is also rotated.
[0084] In the meantime, the solid line arrow presents a rotation of the shaft and the dotted line arrows present rotations of the clutch and the driving gear.
[0085] As shown in FIG. 5 , when the actuator 910 moves down, only the second clutch 932 idles but the first clutch 921 , the first shaft 920 , the first driving gear 941 , the second driving gear 952 , and the second shaft 930 are all rotated.
[0086] In this instance, the first shaft 920 rotates halfway. The driving force for the remaining half rotation is obtained by the second clutch 932 working while the actuator 910 moves up.
[0087] That is, as shown in FIG. 6 , when one end portion of the lever 300 moves down, the other end portion of the lever 300 moves up, and in this instance, the actuator 910 moves upward and drivingly rotates (see the dotted line arrow in FIG. 6 ) the second clutch 932 but idly rotates (the first clutch 921 rotates in the opposite direction to the second clutch and idly rotates).
[0088] In this instance, because the second rack gear part 912 of the actuator 910 interlocks the second clutch 932 , the rectilinear motion of the actuator 910 can convert the rectilinear motion of the actuator 910 into a rotary motion of the second clutch 932 .
[0089] While the second clutch 932 drivingly rotates, the second shaft 930 is rotated, and the second driving gear 952 is rotated by the rotation of the second shaft 930 .
[0090] While the first driving gear 952 , the connection member 960 is also rotated, and the first driving gear 941 is also rotated in the same direction as the second driving gear 952 by the connection member 960 . Moreover, when the first driving gear 941 rotates, the first shaft 920 is also rotated.
[0091] In FIG. 7 , the solid line arrow presents the rotation of the shaft and the dotted line arrow presents the rotations of the clutch and the driving gear.
[0092] As shown in FIG. 7 , when the actuator 910 moves up, only the first clutch 921 idly rotates, but the second clutch 932 , the second shaft 930 , the second driving gear 952 , the first driving gear 941 , and the first shaft 920 are all rotated.
[0093] In this instance, the first shaft 920 rotates as much as the remaining half rotation length, and hence, it can rotate in safety. That is, the first shaft 920 can rotate perfectly along the upward and downward movement of the actuator 910 .
[0094] If the distance ranging from the one end portion of the lever 300 to the fulcrum 800 is longer than the distance ranging from the other end portion of the lever 300 to the fulcrum 800 , when the lever 300 is operated, the force applied to the other end portion of the lever 300 may become greater than the forced applied to the one end portion of the lever 300 .
[0095] Because greater power is applied to the other end portion of the lever 300 not the one end portion, the force to rotate the first shaft 920 and the second shaft 930 becomes greater, so that instant torques of the first shaft 920 and the second shaft 930 rotating by the greater force can be amplified, and hence, the rate of production can be also increased.
[0096] Meanwhile, referring to FIGS. 8 and 9 , the entire configuration of the torque-transmitting device according to a second preferred embodiment of the present invention will be described in brief.
[0097] As shown in FIGS. 8 and 9 , the torque-transmitting device according to the second preferred embodiment of the present invention provides a double structure that has a first torque-transmitting device A and a second torque-transmitting device B.
[0098] In FIG. 8 , the first torque-transmitting device A and the second torque-transmitting device B are connected with each other, but in FIG. 9 , the first torque-transmitting device A and the second torque-transmitting device B are separated from each other.
[0099] As shown in FIGS. 8 and 9 , the structures of the first torque-transmitting device A and the second torque-transmitting device B are the same as the torque-transmitting device of FIG. 1 . That is, the double structure of the torque-transmitting device according to the second preferred embodiment is virtually identical with a state where two torque-transmitting devices of FIG. 1 are mounted in parallel in such a way as to be connected with each other.
[0100] Here, the first torque-transmitting device A and the second torque-transmitting device B are respectively operated by a single driving motor 100 , a first lever 300 a and a second lever 300 b are supported by a single fulcrum 800 , and a first torque device 900 a of the first torque-transmitting device A and a second torque device 900 b of the second torque-transmitting device B respectively operate the first shaft 920 and the second shaft 930 .
[0101] That is, as shown in FIGS. 8 and 9 , the first torque-transmitting device A includes a first driving rotor 220 a and a first slave rotor 200 a driven by the driving motor 100 , a first lever 300 a, a first mounting part 400 a, a second mounting part 500 a, and the first torque device 900 a. Additionally, the second torque-transmitting device B also includes a second driving rotor 220 b and a second slave rotor 200 b driven by the driving motor 100 , a second lever 300 b, a third mounting part 400 b, a fourth mounting part 500 b, and the second torque device 900 b.
[0102] Furthermore, the detailed configuration and the operation principle of the torque-transmitting device according to the second preferred embodiment are also virtually identical with the detailed configuration of the torque-transmitting device according to the first embodiment, and hence, description of the detailed configuration illustrated in FIGS. 8 and 9 will be omitted.
[0103] Meanwhile, FIGS. 10 to 13 illustrate the operation of the torque-transmitting device with the double structure according to the second preferred embodiment. FIG. 10 illustrates the operation of the torque-transmitting device in a state where a first driving rod 700 a of the first torque-transmitting device A is located near the top dead point (b′˜b″) of the first slave rotor 200 a and a second driving rod 700 b of the second torque-transmitting device B is rotated toward the bottom dead point of the second slave rotor 200 b. FIG. 11 illustrates the operation of the torque devices 900 a and 900 b in the condition illustrated in FIG. 10 .
[0104] Moreover, FIG. 12 illustrates the operation of the torque-transmitting device in a state where the first driving rod 700 a of the first torque-transmitting device A is located near the bottom dead point (a′˜a″) of the first slave rotor 200 a and a second driving rod 700 b of the second torque-transmitting device B is rotated toward the top dead point of the second slave rotor 200 b. FIG. 13 illustrates the operations of the torque devices 900 a and 900 b in the condition of FIG. 12 .
[0105] First, as shown in FIG. 10 , when the driving motor is operated and the first driving rotor 200 a and the second slave rotor 200 b are respectively rotated, the first driving rod 700 a and the second driving rod 700 b eccentrically fixed to the first driving rotor 200 a and the second slave rotor 200 b upwardly or downwardly moves end portions of the first lever 300 a and the second lever 300 b while respectively moving.
[0106] In this instance, as shown in FIGS. 10 and 11 , the first actuator 910 a disposed on the first connection part 710 a connected to the other end portion of the first lever 300 a of the first torque-transmitting device A also moves down. While moving down, the first actuator 910 a drivingly rotates the first clutch 921 a (indicated as the dotted line arrow in the drawing) and idly rotates the second clutch 932 a (the second clutch is rotated in the opposite direction of the first cultch but idles.).
[0107] In this instance, because a first rack gear part 911 a of the first actuator 910 a can convert a rectilinear motion of the first actuator 910 a into a rotary motion of the first clutch 921 a.
[0108] While drivingly rotating, the first clutch 921 a rotates the first shaft 920 , and the first driving gear 941 a is also rotated by the rotation of the first shaft 920 .
[0109] When the first driving gear 941 a rotates, the first connection member 960 a is also rotated, and the second driving gear 952 a is also rotated in the same direction as the first driving gear 941 a by the first connection member 960 a. Furthermore, when the second driving gear 952 a is rotated, the second shaft 930 is also rotated.
[0110] Additionally, the second actuator 910 b disposed on the second connection part 710 b connected to the other end portion of the second lever 300 b of the second torque-transmitting device B moves up. While moving up, the second actuator 910 b drivingly rotates the fourth clutch 932 b (see the dotted line arrow in the drawing) and idly rotates the third clutch 921 b (the third clutch rotates in the opposite direction of the fourth clutch but idles).
[0111] In this instance, because the fourth rack gear part 912 b of the second actuator 910 b interlocks the fourth clutch 932 b, the rectilinear motion of the second actuator 910 b can be converted into a rotary motion of the fourth clutch 932 b.
[0112] While drivingly rotating, the fourth clutch 932 b rotates the second shaft 930 , and the fourth driving gear 952 b is also rotated by the rotation of the second shaft 930 .
[0113] While rotating, the fourth driving gear 952 b rotates the second connection member 960 b, and the third driving gear 941 b is also rotated in the same direction as the fourth driving gear 952 b due to the second connection member 960 b. Furthermore, the third driving gear 941 b rotates the first shaft 920 while rotating.
[0114] Accordingly, the first shaft 920 and the second shaft 930 are rotated by the first torque device 900 a and the second torque device 900 b )
[0115] In this instance, as shown in FIG. 10 , when the first driving rod 700 a of the first torque-transmitting device A passes near the top dead point of the first slave rotor 200 a (in the drawing, a position between b′ and b″), the first lever 300 a may be hardly operated, and hence, the first actuator 910 a may hardly do the rectilinear motion.
[0116] Even in the above case, because the second lever 300 b of the second torque-transmitting device B makes the second actuator 910 b do the rectilinear motion, the second torque-transmitting device B can continuously drive the first shaft 920 and the second shaft 930 by additionally adding the first torque-transmitting device A.
[0117] In FIG. 11 , the solid line arrow presents the rotation of the shaft and the dotted line arrow presents the rotations of the clutch and the driving gear.
[0118] Meanwhile, as shown in FIGS. 12 and 13 , when the first driving rod 700 a of the first torque-transmitting device A passes near the bottom dead point (position between a′ and a″ in FIG. 12 ), the first actuator 910 a disposed on the first connection part 710 a connected to the other end portion of the first lever 300 a of the first torque-transmitting device A moves up, and the first actuator 910 a drivingly rotates the second clutch 932 a (see the dotted line arrow in the drawing) and idly rotates the first clutch 921 a while moving up.
[0119] In this instance, as shown in FIGS. 12 and 13 , because the second rack gear part 912 a of the first actuator 910 a interlocks the second clutch 932 a, the rectilinear motion of the actuator 910 a can be converted into a rotary motion of the second clutch 932 a.
[0120] The second clutch 932 a rotates the second shaft 930 while drivingly rotating, and the second driving gear 952 a is rotated by the rotation of the second shaft 930 .
[0121] The second driving gear 952 a rotates the connection member 960 a while rotating, and the first driving gear 941 a is also rotated in the same direction as the second driving gear 952 a by the connection member 960 a. Moreover, the first driving gear 941 a rotates the first shaft 920 while rotating.
[0122] Moreover, the second actuator 910 b disposed on the second connection part 710 b connected to the other end portion of the second lever 300 b of the second torque-transmitting device B moves down. While moving down, the second actuator 910 b drivingly rotates the second clutch 921 b (see the dotted line arrow in the drawing) and idly rotates the fourth clutch 932 b.
[0123] In this instance, because the third rack gear part 911 b of the second actuator 910 b interlocks the third clutch 921 b, the rectilinear motion of the second actuator 910 b can be converted into a rotary motion of the third clutch 921 b.
[0124] The third clutch 921 b rotates the first shaft 920 while drivingly rotating, and the third driving gear 941 b is also rotated by the rotation of the first shaft 920 .
[0125] When the third driving gear 941 b is rotated, the second connection member 960 b is also rotated, and the fourth driving gear 952 b is rotated in the same direction as the third driving gear 941 b by the second connection member 960 b. Additionally, when the fourth driving gear 952 b is rotated, the second shaft 930 is also rotated.
[0126] Accordingly, the first shaft 920 and the second shaft 930 are rotated by the first torque device 900 a and the second torque device 900 b.
[0127] In this instance, as shown in FIG. 12 , when the first driving rod 700 a of the first torque-transmitting device A passes near the bottom dead point of the first slave rotor 200 a (in the drawing, the position between a′ and a″), the first lever 300 a may be hardly operated, and hence, the first actuator 910 a may hardly do the rectilinear motion.
[0128] Even in the above case, because the second lever 300 b of the second torque-transmitting device B makes the second actuator 910 b do the rectilinear motion, the second torque-transmitting device B can continuously drive the first shaft 920 and the second shaft 930 by additionally adding the first torque-transmitting device A.
[0129] The torque-transmitting device according to the present invention can convert torque input at one end portion of the lever into a greater force at the other end portion of the lever using the principle of lever to thereby gain a great rate of production. | A torque-transmitting device uses the principle of leverage in such a way that torque input at one end of a lever can become a greater torque per unit time at the other end of the lever, and can be achieved in a uniform fashion. The torque-transmitting device of the present invention comprises: a drive motor; a first mounting unit for rotatably mounting a rotational drive body which rotates on receiving a drive force from the drive motor; a second mounting unit provided at a predetermined distance from the first mounting unit; a lever which is rotatably secured on a support member provided between the first mounting unit and the second mounting unit, and of which one end is mounted on the first mounting unit where it turns as it is driven by the drive motor and of which the other end is mounted on the second mounting unit where it turns; an actuator which is linked to the other end of the lever and performs a linear reciprocating motion as the lever turns in the top-to-bottom direction; and a torque device for converting the linear reciprocating motion of the actuator into a rotational motion and generating torque for driving a predetermined loading device. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to an improved process for the preparation of polynuclear aromatic polyamines in which the reaction product is prepared by condensing aniline with formaldehyde in the presence of water and acidic catalysts and is worked up by extraction with a hydrophobic solvent. The acid catalyst that accumulates in the aqueous phase during the extraction process is reused.
It is already known that in the preparation of polynuclear aromatic polyamines by condensation of aniline with formaldehyde in the presence of water and acidic catalysts, the accumulating aqueous reaction mixture can be worked up by extraction with a hydrophobic solvent and that the acid catalyst that accumulates during extraction in the aqueous phase can be reused. See, for example, U.S. Pat. Nos. 4,093,658, 4,087,459, 4,061,678, 3,996,283, and 3,952,042 and DE-OS No. 2,343,658.
The main advantage of the processes according to the above references is the absence of the need to neutralize the catalyst. The catalyst need not be neutralized because it accumulates in the aqueous phase during workup of the acidic reaction mixture by extraction and may be returned to the beginning of the process and reused. In addition, certain variations of this known principle, such as those described in U.S. Pat. Nos. 4,093,658 or 4,087,459, provide for the specific preparation of polyamine mixtures with either an increased or reduced content of 2,4'-isomers. The products obtained by the processes disclosed in the above references correspond in suitability as starting products for the preparation of polyisocyanates to the conventional polyamines of the diphenylmethane series produced by neutralizing the acid catalyst. Thus, the property level of polyurethane foams produced from such polyisocyanate mixtures of the diphenylmethane series is substantially the same in both cases. However, a disadvantage of the processes according to the references cited above is that considerable quantities of hydrophobic solvent and aniline must be used solely for the extraction used for the workup of the end products. As a consequence, these processes involve a considerable amount of distillation in the workup of the organic phase and hence a considerable consumption of energy.
The object of the present invention is to provide a new, improved process for the preparation of polynuclear aromatic polyamines from aniline and formaldehyde in the presence of acidic catalysts. The improved process is intended to improve upon the advantages of the known processes and, in addition, to provide for the preparation of products of improved quality with less distillation and, hence, lower energy consumption. This object is achieved by the process according to the invention which is described in detail hereinafter.
SUMMARY OF THE INVENTION
The present invention relates to a process for the preparation of polynuclear aromatic polyamines by reacting aniline with formaldehyde in the presence of water and acid catalysts in a single-stage or two-stage reaction within a temperature range of from 0° to 180° C. The reaction is optionally preceded by an aminal preliminary step in which N,N'-disubstituted aminal is formed in the absence of acid catalyst and is then converted into the desired end product in one or more stages in the presence of acid catalyst at a temperature in the range from 0° to 180° C. The resultant reaction mixture is then worked up by extraction with a hydrophobic solvent containing aniline. The resultant organic phase is separated and distilled into (i) a distillate consisting of aniline-containing solvent that is reused in the extraction stage, optionally after addition of fresh aniline, and (ii) a distillation residue consisting essentially of end product of the process. The aqueous phase, for which the water comprises water formed during the condensation reaction and water introduced into the system with the aqueous solution of formaldehyde, contains acid catalyst that accumulates during the extraction. The aqueous phase is recycled, with water being removed in a water separator downstream from the aminal preliminary stage and upstream of the first stage of the reaction and/or in an evaporator downstream from the extraction stage and upstream of the first stage of the reaction and the acid catalyst being reused in the reaction. The process is further characterized in that
(a) formaldehyde in the form of an aqueous solution is reacted by mixing said formaldehyde in an aminal preliminary stage with an aniline-containing hydrophobic solvent and/or in the first stage of the reaction with an aniline-containing hydrophobic solvent and the recycled aqueous phase containing the catalyst in the form of amine salts,
(b) upon completion of the reaction, the resultant two-phase reaction mixture is separated into an aqueous phase and an organic phase in a phase separator upstream of the product extraction stage,
(c) organic phase that accumulates in the phase separator is extracted in a re-extraction stage downstream from the product extraction stage using the substantially product-free aqueous phase obtained from the product extraction stage,
(d) an aqueous phase that accumulates in the re-extraction stage and which is somewhat product-enriched (due to the introduction of the organic phase from the phase separator) is returned to the reaction process,
(e) a product-depleted organic phase that accumulates in the re-extraction stage is used as part of the extractant in the main product extraction stage,
(f) the aqueous phase that accumulates in the phase separator is extracted in the product extraction stage with hydrophobic solvent containing aniline and, optionally, end product,
(g) the organic phase that accumulates in the product extraction stage is separated in a distillation stage into a distillate consisting of aniline-containing solvent and a distillation residue consisting essentially of end product, and
(h) the distillate that accumulates in the distillation stage is separated, optionally after addition of fresh aniline, into two component streams, one component stream being used at the beginning of the process according to (a) above, and the other component stream being used together with the organic phase leaving the re-extraction stage as extractant for the aqueous phase in the product extraction stage.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 and 2 schematically set forth various embodiments of the present invention.
DESCRIPTION OF THE INVENTION
The process according to the invention provides the following advantages relative to the previously known processes:
As in the known processes, the acid catalyst is reused and is not destroyed by neutralization.
The mixtures accumulating as distillate during the distillative workup of the organic phase containing the end products of the process according to the invention may be reused without further separation into their constituents by distillation. These distillates can be used both as extractant for the aqueous phase in the product extraction step and at the beginning of the process, optionally after addition of more aniline.
The process according to the invention can be varied within wide limits with respect to the distribution of homologs in the end products (i.e., ratio of diamines to higher polyamines), although products having a comparatively low content of ortho isomers are always formed.
The polyisocyanates produced from the end products of the process according to the invention surprisingly give polyurethane foams showing a distinctly fainter intrinsic color than corresponding polyurethane foams based on known polyisocyanate mixtures of the diphenylmethane series.
Compared with the known "extraction processes" mentioned above, the total quantity of solvent can be considerably reduced in the process according to the invention. Thus, the concentration of MDA in the organic phases accumulating can be considerably increased and hence the amount of distillation required for working up the organic phases can be correspondingly reduced.
Starting materials for the process according to the invention are aniline and formaldehyde. The formaldehyde is preferably used in the form of an aqueous solution having a formaldehyde content of 20 to 50% by weight.
The hydrophobic solvents used are inert solvents boiling at temperatures in the range from about 30° to about 250° C., preferably in the range from about 80° to about 200° C. Suitable hydrophobic solvents include, for example, chlorobenzene, dichlorobenzenes, benzene, toluene, xylene, dichloroethane, chloroform, and carbon tetrachloride. Preferred hydrophobic solvents include xylenes (i.e., commercial xylene mixtures), particularly o-xylene.
The acid catalyst is a water-soluble acid having a pK a below 2.5, preferably below 1.5. Suitable acid catalysts include hydrochloric acid, hydrobromic acid, sulfuric acid, trifluoroacetic acid, methanesulfonic acid, and phosphoric acid. Hydrochloric acid is a preferred catalyst. The acids may also be used in admixture with acidic or neutral salts of such acids, such as the corresponding ammonium salts or the corresponding alkali salts, but the use of such salts is less preferred. The acids are present in the circulation system according to the invention in the form of the corresponding ammonium salts of the bases present in the aqueous circuit.
The process according to the invention may be carried out in a single stage or in two stages and with or without a preliminary aminal stage. However, when the reaction is carried out in a single stage, it is always best preceded by an aminal preliminary stage.
As used herein, the term "single-stage reaction" is understood to refer to a variant of the process in which, after addition of the acid catalyst, the aminal is heated within a short period of less than 10 minutes (preferably less than 5 minutes) to an elevated temperature of 60° to 180° C. (preferably 80° to 150° C.) where it is rearranged into the end product, or a variant in which the aminal is directly mixed with the circulated aqueous catalyst phase at the elevated temperature of 60° to 180° C. (preferably 80° to 150° C.) and the mixture subsequently heated if necessary to the desired final temperature.
As used herein, the term "two-stage reaction" is understood to refer to a variant of the process in which, after addition of the acid catalyst or the reaction mixture of aniline, formaldehyde, and acid catalyst, the aminal is first held at 0° to 60° C. (preferably at 30° to 60° C.) for 10 to 90 minutes (preferably for 15 to 60 minutes) in a first stage of the reaction and is then held at 60° to 180° C. (preferably at 60° to 150° C. and more preferably at 100° to 150° C.) for 30 to 180 minutes (preferably for 30 to 120 minutes) in a second stage of the reaction. In this preferred two-stage variant of a multiple-stage reaction, the first stage comprises a rearrangement of the aminal or, in the absence of an aminal preliminary stage, condensation of the starting materials to N-benzylaniline which is rearranged at elevated temperature in the second stage to the nuclear-substituted end product. In one particular variant of the two-stage embodiment (without or, preferably, with an aminal preliminary stage), the first stage is carried out with only a partial stream of the aqueous catalyst phase, generally as less than 50% and preferably less than 15% of the stream. After completion of the first stage and before completion of the last (which is generally the second) stage of the reaction, the reaction is completed in the presence of the entire catalyst phase.
The process may be carried out both continuously and batchwise. When the process is carried out continuously, the times described herein relate to the average residence time of the reaction mixture in the individual stages. When the reaction is preceded by an aminal preliminary stage, the (average) residence time of the starting materials in that stage is generally 10 to 60 minutes and is preferably 15 to 60 minutes.
The temperature in the aminal preliminary stage is generally in the range from about 20° to about 100° C. and is preferably in the range from about 20° to about 60° C. All stages of the process are preferably carried out under the intrinsic pressure of the system and preferably in an inert gas atmosphere (e.g., nitrogen).
The flow diagrams shown in FIGS. 1 and 2 are intended to illustrate the process according to the invention. In these Figures, the reference numerals have the following meanings:
(1) a tank for aqueous formaldehyde solution,
(2) a tank for aniline,
(3) a condensation reactor (aminal preliminary stage),
(4) a water separator,
(5) the first reaction stage,
(6) the second reaction stage,
(7) a phase separator,
(8) the product extraction stage,
(9) the re-extraction stage,
(10) a water evaporator,
(11) the product distillation stage,
(12) a washing stage,
(13) a tank for wastewater, and
(14) a tank for end product of the process.
The references letters A through R and X and Y denote the product streams referred to below and in the Examples.
In the single stage reaction process, the reaction stages (5) and (6) are combined into a single reaction stage. Both the first and the second reaction stage may be carried out in a single reactor and in several reactors arranged in series. Cascades of stirred tank reactors and/or column reactors arranged in series have proved to be particularly effective for maintaining the residence times indicated. The extraction stage may also be carried out in one or more extractors arranged in series. The usual countercurrent extractors are preferably used for this purpose.
In the simplest case, the distillation stage (11) consists of a distillation column designed in such a way that hydrophobic solvent and aniline can be substantially separated from the end product.
A particular advantage of the process according to the invention is the absence of the need to separate the hydrophobic solvent and aniline. Separation is not needed because the aniline content of the distillate is always less than the amount required for reuse and must be adjusted for reuse by addition of fresh aniline. Thus, it is possible to use energy-saving multistage distillation techniques.
The water formed during the condensation and the water introduced into the system with the aqueous formaldehyde solution must be removed from the system at some suitable point in order to maintain a constant water volume. If a preliminary aminal stage (3) is employed, the water is preferably removed in the water separator (4) before the aminal and the acid catalyst are brought together. If no aminal preliminary stage is employed, the water is preferably removed in a water evaporator (10) placed downstream from the re-extraction stage (9) or placed between the product extraction stage (8) and the re-extraction stage (9). This water evaporator is preferably operated on the principle of flash evaporation by application of vacuum. However, water may in principle also be removed from the system by distillation at any other point.
In the practical application of the process according to the invention, several embodiments or variants are possible and are described in detail below.
In a first preferred embodiment of the process according to the invention (illustrated, for example, in FIG. 1), the aqueous formaldehyde solution (A) is fed into aminal preliminary stage (3), where reaction with a mixture (B) of aniline and hydrophobic solvent takes place. Product stream (B) is part of the distillate (O) from the distillation stage (11), to which is generally added an additional quantity of aniline (Q). The molar ratio of aniline to formaldehyde in the aminal stage is generally between 1.5:1 and 25:1, preferably between 1.8:1 and 10:1. The ratio by weight of aniline to hydrophobic solvent in (B) is generally between 1:4 and 3:1, preferably between 1:1 and 2:1. The reaction in the aminal stage (3) takes place at temperatures within the ranges mentioned above.
Following stage (3), the aqueous phase formed from the water of condensation and the formalin water, and which also contains the water-soluble impurities of the formaldehyde and aniline, is mechanically separated in a separator (4), preferably at a temperature below 60° C. The residual organic phase of this separation is transferred to the reactor (5) and combined with the aqueous stream (C') at temperatures below 60° C. In this first preferred embodiment of the process according to the invention, stream (C') comprises the entire quantity of catalyst phase (C) to be recycled. The content of aniline-formaldehyde condensates in this phase (C) is generally between 10 and 40% by weight and is preferably between 15 and 30% by weight. Thus, at this point, the total arylamine content (including aniline) is generally from 30 to 70% by weight, preferably from 40 to 60% by weight. The degree of protonation is 25 to 75%, preferably 45 to 65%. As used herein, the term "degree of protonation" refers to the percentage of basic amine nitrogen atoms which are present in the form of ammonium groups, i.e., "protonated." The ratio by weight of catalyst phase (C) to the organic phase from (4) is generally between 1:10 and 100:1, preferably between 0.5:1 and 3:1.
In this first, continuous-method embodiment of the process according to the invention, the reactor (5) represents the "first reaction stage" described above and is operated under the above-mentioned conditions of temperature and reaction time. In general, this reactor consists of a multistage cascade of stirred tank reactors or a single-stage or multistage column reactor in which the temperature rises from around 20° C. at the beginning to 60° C. at the end.
The two-phase reaction mixture is transferred from the first reaction stage (5) to the second reaction stage (6), which also consists of a multistage cascade of stirred tank reactors or of a single-stage or multistage column reactor. This second reaction stage is also operated under the above-mentioned conditions of reaction temperature and average residence time. The two-phase reaction mixture preferably passes through a temperature profile beginning at 60° C. and ending at a temperature of from 95° to 160° C. (preferably from 120° to 140° C.) in reaction stage (6). Using this preferred temperature profile, reaction times of up to 60 minutes in reaction stage (6) are generally sufficient.
The two-phase reaction mixture leaving the second reaction stage (6) is then separated in the phase separator (7) (at temperatures preferably in the range from 80° to 100° C.) into an organic phase (E) and an aqueous phase (F).
The aqueous phase (F) is transferred to the product extraction stage (8). In the product extraction stage (8), which preferably comprises several stages and is preferably operated at temperatures of 80° to 110° C., the end products are extracted from aqueous phase (F) in exchange for aniline and transferred into an organic phase (N). The extractant (G) used in the product extraction stage (8) is a mixture of hydrophobic solvent and aniline and may optionally contain small amounts of aniline-formaldehyde condensates. The ratio by weight of aniline (plus any aniline-formaldehyde condensates) to solvent is generally between 0.5:1 and 3:1, preferably between 1:1 and 2:1. The weight ratio of extractant (G) to aqueous phase (F) is generally between 0.5:1 and 3:1, preferably between 0.7:1 and 2:1.
The organic phase (N) is transferred to the distillation stage (11), optionally after passing through a catalyst washing stage (12) in which any traces of catalyst present are removed. In distillation stage (11), a distillation residue (P), which represents the end product of the process and which is collected in tank (14), is separated by distillation. The distillation stage (11) may consist, for example, of a single stage evaporator which produces a distillate (O) in addition to a distillation residue (P). Besides aniline, the distillate (O) contains all of the hydrophobic solvent from (N) and is used for preparing solutions (B) and (G). However, since the aniline content in distillate (O) is always less than the necessary aniline concentration in the extractant (G), the deficit must be made up, for example, by combining (O) with fresh aniline (Q) from tanks (2), thereby forming product stream (R). Product stream (R) is divided into product streams (B) and (M).
Product stream (B) is returned to the aminal stage (3), whereas product stream (M) is combined with product stream (L) from the re-extraction stage (9) to form the extractant (G). Product stream (B) may also be used with the same composition as distillation (O) at the beginning of the process, so that component stream (M) entering (G) is brought to the desired composition with only a partial quantity of (Q), with the remainder of (Q) being added to and mixed at a suitable point (for example, between stages (6) and (8)) with the two-phase system (i.e., between stages (6) and (7)) or with the aqueous phase (i.e., between stages (7) and (8)).
The aqueous phase (H) from the main extraction stage (8), which contains only very small amounts (less than 5% by weight and preferably less than 2% by weight) of process products (aniline-formaldehyde condensates), is extracted in the multistage re-extraction stage (9), generally at temperatures of 40° to 110° C. The extractant in this re-extraction stage (9) is product stream (E), the organic phase separated off in separator (7). The process products contained in (E) are exchanged almost completely for aniline and transferred to an aqueous phase (I), resulting in an organic phase (L) which is substantially free from products of the process.
The organic phase (L) from the re-extraction stage (9) is a component part of the extractant (G). Thus, the extractant is generally formed by combining the partial quantity (M) of stream (R) with organic phase (L). However, the extraction in stage (8) may also be carried out in a multistage extractor by initially using stream (M) alone in the first part or the last part (with reference to the aqueous phase) of the product extraction stage (8) and by feeding stream (L) in a later part or an earlier part (with reference to the aqueous phase) of the product extraction stage (8).
The aqueous phase (I) that accumulates in re-extraction stage (9), may be used as the catalyst solution (C) to be recycled. However, a quantity of water (K), which may generally make up as much as 80% by weight of the water present in (8), but which is preferably less than 50% by weight, is removed from aqueous phase (I) in evaporator (10). This quantity of water (K) is added to the reaction mixture between the second reaction stage (6) and the main extraction stage (8) or is used to wash out final traces of catalyst from the organic phase (N) in the catalyst washing stage (12) for subsequent addition to the reaction mixture as product stream (D) between stages (6) and (8). When this procedure for removal of water in evaporator (10) and recycling is adopted, the reaction in reactors (5) and (6) is carried out using a lower water content in the aqueous phase than is used in the extraction in extraction stage (8). This procedure can thus often facilitate the extraction in stage (8).
The first preferred embodiment of the process according to the invention described above may be modified in various ways.
In a first variant of the first preferred embodiment, aminal stage (3) is completely or partly eliminated. In practice, this means that a partial quantity of the mixture of aniline and hydrophobic solvent (B') and a partial quantity of the aqueous formaldehyde (A') used in the reaction are not introduced into aminal stage (3), but rather upstream of the first reaction stage (5). In the extreme case of a complete absence of an aminal preliminary stage, the total quantity of the mixture of aniline and hydrophobic solvent and the total quantity of aqueous formaldehyde may be delivered directly to the first reaction stage (5). In the absence of an aminal preliminary stage, however, the reaction always must be carried out in two stages using the reaction stages (5) and (6), as described above. Where this procedure is adopted, the introduced water and the water of condensation are, of course, only partly removed by the phase separator (4), if removed at all. Removal of this water would then be possible, for example, by diverting from the distillate from evaporator (10) a partial stream (K') which is directly introduced into the wastewater tank (13).
In a second variant, reaction stages (5) and (6) may be combined into a single reaction stage operated under the above-mentioned conditions of reaction temperature and reaction time. When carried out in a single stage, however, the reaction always must be preceded by an aminal preliminary stage (3).
In both the first variant and the second variant, the product streams are regulated in such a way that a molar ratio of aniline to formaldehyde of 1.5:1 to 25:1 is present in stage (5), with the arylamine introduced with catalyst stream (C) being included in the calculation.
In a third variant combined with the first variant, the recycled catalyst solution (C) is divided into two streams such that the reaction in the first stage takes place in the presence of only part (C') of the recycled catalyst solution, with the remaining quantity of catalyst solution (C") being added between the reaction stages (5) and (6). The weight ratio between the organic phase in stage (5) and aqueous phase (C') (initially introduced, for example, in the first stirred tank reactor of stage (5)) is between 1:1 and 100:1, preferably between 3:1 and 30:1.
In a fourth variant combined with the variants mentioned above, a partial quantity (X) of up to 50% by weight
(preferably up to 15% by weight) of the entire aqueous phase from product extraction stage (8) is removed from the aqueous phase leaving stage (8) and returned to the first stage of the reaction. The entire quantity of recycled catalyst phase (C) is preferably introduced into the system as stream (C") downstream from stage (5). The catalyst in stage (5) then consists almost exclusively of aniline hydrochlorides present in (X), while the catalyst phase (C) contains, in addition to aniline hydrochlorides, hydrochlorides of process products.
In a fifth variant, which may be combined with the preceding variants, a partial stream (Y) is removed from aqueous phase (I) leaving the re-extraction stage (9) and returned to the reaction mixture upstream of separator (7). This variant is particularly useful in reducing the ratio of organic phase to aqueous phase in re-extraction stage (9), thereby enabling the re-extraction stage (9) to be operated under optimal conditions, i.e., at weight ratio of organic phase (E) to aqueous phase (H) of less than 1.5:1, preferably of less than 1:1.
A second embodiment of the process according to the invention (illustrated, for example, in FIG. 2) is distinguished from the first preferred embodiment by the arrangement of the evaporator stage (10) upstream of the re-extraction stage (9). This second embodiment is also amenable to the variants described above for the first embodiment, although stream (X) in the fourth variant may also be removed downstream from the evaporator stage (10) and upstream of the re-extraction stage (9) and stream (Y) in the fifth variant may form part of the recycled aqueous catalyst solution (C).
Reversal of the order of stages (9) and (10), as illustrated in FIG. 2, results in an increase in the ratio of organic phase (E) to aqueous phase (H) for a given quantity of acid in phase (H), thereby allowing the efficiency of the re-extraction stage (9) to be optimized.
The main purpose of the re-extraction stage (9) is to remove aniline-formaldehyde condensates almost completely from the organic phase (E), an objective which is generally achieved when the phase ratio by weight of (E) to (H) is below 1.5:1, preferably below 1:1.
The following examples further illustrate details for the process of this invention. The invention, which is set forth in the foregoing disclosure, is not to be limited either in spirit or scope by these examples. Those skilled in the art will readily understand that known variations of the conditions of the following procedures can be used. Unless otherwise noted, all temperatures are degrees Celsius and all percentages are percentages by weight. The term "polyarylamine" is used generically to include all the polyamines of the diphenylmethane series present in mixtures in the respective product streams.
EXAMPLES
EXAMPLE 1 (FIG. 1)
In a reactor (3) consisting of two stirred tanks arranged one after the other, a 30% aqueous formalin solution (product stream (A)) is reacted at 40° C. with an aniline-xylene mixture (product stream (B)).
(A) 0.375 kg/h formaldehyde
0.875 kg/h water
(B) 2.327 kg/h aniline
1.940 kg/h o-xylene
In a water separator (4), the lower aqueous phase is separated as wastewater and collected in a wastewater tank (13). The upper organic phase is transferred to a second reactor (5) consisting of three stirred tanks in which the organic phase is mixed with the product stream (C).
(C) 0.881 kg/h polyarylamine
0.563 kg/h aniline
0.328 kg/h hydrochloric acid
1.975 kg/h water
The temperatures in the three tanks of the reactor (5) are regulated at, in sequence, 30° C., 40° C., and 60° C.
Another reactor (6) likewise consists of three stirred tanks in which the temperatures are regulated by heating at 100° C., 135° C., and 140° C. at the intrinsic pressure of the system.
After the reaction mixture cools to 95° C. and expands to normal pressure, the HCl wash water from the washing stage (12) (product stream (D)) is added. The organic phase (product stream (E)) and the aqueous phase (product stream (F)) are then separated from each other in the phase separator (7).
(E) 0.870 kg/h polyarylamine
0.703 kg/h aniline
1.940 kg/h o-xylene
(F) 2.130 kg/h polyarylamine
0.218 kg/h aniline
0.328 kg/h hydrochloric acid
2.881 kg/h water
The aqueous phase (F) is then continuously extracted by countercurrent extraction with an aniline-xylene mixture (product stream (G)) in the extraction column (8)
(G) 0.038 kg/h polyarylamine
4.159 kg/h aniline
4.143 kg/h o-xylene
changing into the polyarylamine-depleted aqueous phase (H)
(H) 0.049 kg/h polyarylamine
1.370 kg/h aniline
0.328 kg/h hydrochloric acid
2.881 kg/h water
which is used in another extraction column (9) for the countercurrent extraction of the organic phase (E) separated in phase separator (7).
The aqueous phase (product stream (I)) that accumulates in (9), which is enriched with polyarylamine in relation to the aqueous phase (H),
(I) 0.881 kg/h polyarylamine
0.563 kg/h online
0.328 kg/h hydrochloric acid
2.881 kg/h water
is concentrated in the distillation stage (10), with concomitant removal of the distillate as product stream (K), and is then returned to the reactor (5) as product stream (C).
(K) 0.906 kg/h water
The organic phase that accumulates in extraction stage (9), in which the polyarylamine content is depleted relative to (E), is used as the product stream (L) component of extractant in product extraction stage (8). Product stream (L) and the aniline-xylene mixture (M) together constitute product stream (G), which forms the total quantity of extractant used in product extraction stage (8).
(L) 0.038 kg/h polyarylamine
1.510 kg/h aniline
1.940 kg/h o-xylene
(M) 2.649 kg/h aniline
2.203 kg/h o-xylene
The organic phase containing the reaction product which accumulates in the product extraction stage (8) (product stream (N)) is extracted in another three- to five-stage extraction column (washing stage (12)), with the distillate from distillation stage (10) consisting essentially of water (product stream (K)).
(N) 2.119 kg/h polyarylamine
3.007 kg/h aniline
4.143 kg/h o-xylene
(K) 0.906 kg/h water
In the washing stage (12), the HCl content of the product stream (N), which amounts to about 0.2-0.3% by weight, is reduced under the described conditions to less than 0.01% by weight. The HCl-containing wash water is recycled into the reaction mixture between stages (6) and (7) as product stream (D). The organic phase leaving the washing stage is separated in a distillation stage (11) into a distillate (product stream (O)) and a distillation residue (product stream (P)).
(O) 3.007 kg/h aniline
4.143 kg/h o-xylene
(P) 2.119 kg/h polyarylamine
After addition of fresh aniline (product stream (Q)) from storage tank (2) to product stream (O), the aniline-xylene mixture thus prepared (product stream (R)) is divided and used as product streams (B) and (M).
The distillation residue (product stream (P)) of the distillation stage (11) has the following composition:
0.2% 2,2'-diaminodiphenylmethane
4.3% 2,4'-diaminodiphenylmethane
46.3% 4,4'-diaminodiphenylmethane
0.2% N-methyl-substituted diaminodiphenylmethanes
22.2% triamines
11.1% tetramines
15.6% polyamines of higher than tetrafunctionality
EXAMPLE 2 (FIG. 1)
In a reactor (3) consisting of two stirred tanks arranged one after the other, a 30% aqueous formalin solution (product stream (A)) from storage tank (1) is reacted at 40° C. with an aniline-xylene mixture (product stream (B)).
(A) 0.500 kg/h formaldehyde
1.166 kg/h water
(B) 3.103 kg/h aniline
2.586 kg/h o-xylene
In a water separator (4), the lower aqueous phase is separated as wastewater and collected in a wastewater tank (13). The upper organic phase is transferred to a second reactor (5) consisting of three stirred tanks in which the organic phase is mixed with the product stream (C).
(C) 0.805 kg/h polyarylamine
1.771 kg/h aniline
0.586 kg/h hydrochloric acid
3.530 kg/h water
The temperatures in the three tanks of the reactor (5) are regulated at, in sequence, 35° C., 50° C., and 60° C.
Another reactor (6) likewise consists of three stirred tanks in which the temperatures are regulated by heating at 100° C., 135° C., and 140° C. at the intrinsic pressure of the system.
After the reaction mixture cools to 95° C. and expands to normal pressure, the HCl wash water from the washing stage (12) (product stream (D)) is added. The organic phase (product stream (E)) and the aqueous phase (product stream (F)) are then separated from each other in the phase separator (7).
(E) 0.734 kg/h polyarylamine
1.460 kg/h aniline
2.586 kg/h o-xylene
(F) 2.897 kg/h polyarylamine
0.779 kg/h aniline
0.586 kg/h hydrochloric acid
5.148 kg/h water
The aqueous phase (F) is then continuously extracted by countercurrent extraction with an aniline-xylene mixture (product stream (G)) in the extraction column (8)
(G) 0.048 kg/h polyarylamine
7.893 kg/h aniline
7.215 kg/h o-xylene
changing into the polyarylamine-depleted aqueous phase (H)
(H) 0.110 kg/h polyarylamine
2.650 kg/h aniline
0.586 kg/h hydrochloric acid
5.148 kg/h water
which is used in another extraction column (9) for the countercurrent extraction of the organic phase (E) separated in phase separator (7).
The aqueous phase (product stream (I)) that accumulates in (9), which is enriched with polyarylamine in relation to the aqueous phase (H),
(I) 0.805 kg/h polyarylamine
1.771 kg/h aniline
0.586 kg/h hydrochloric acid
5.148 kg/h water
is concentrated in the distillation stage (10), with concomitant removal of the distillate as product stream (K), and is then returned to the reactor (5) as product stream (C).
(K) 1.618 g/h water.
The organic phase that accumulates in extraction stage (9), in which the polyarylamine content is depleted relative to (E), is used as the product stream (L) component of extractant in product extraction stage (8). Product stream (L) and the aniline-xylene mixture (M) together constitute product stream (G), which forms the total quantity of extractant used in product extraction stage (8).
(L) 0.048 kg/h polyarylamine
2.339 kg/h aniline
2.586 kg/h o-xylene
(M) 5.554 kg/h aniline
4.629 kg/h o-xylene
The organic phase containing the reaction product which accumulates in the product extraction stage (8) (product stream (N)) is extracted in another three- to five-stage extraction column (washing stage (12)), with the distillate from distillation stage (10) consisting essentially of water (product stream (K)).
(N) 2.835 kg/h polyarylamine
6.022 kg/h aniline
7.215 kg/h o-xylene
(K) 1.619 kg/h water
In the washing stage (12), the HCl content of the product stream (N), which amounts to about 0.2-0.3% by weight, is reduced under the described conditions to less than 0.01% by weight. The HCl-containing wash water is recycled into the reaction mixture between stages (6) and (7) as product stream (D). The organic phase leaving the washing stage (12) is separated in a distillation stage (11) into a distillate (product stream (O)) and a distillation residue (product stream (P)).
(O) 6.027 kg/h aniline
7.215 kg/h o-xylene
(P) 2.835 kg/h polyarylamine
After addition of fresh aniline (product stream (Q)) from storage tank (2) to product stream (O), the aniline-xylene mixture thus prepared (product stream (R)) is divided and used as product streams (B) and (M).
The distillation residue (product stream (P)) of the distillation stage (11) has the following composition:
0.4% 2,2'-diaminodiphenylmethane
5.9% 2,4'-diaminodiphenylmethane
58.7% 4,4'-diaminodiphenylmethane
0.2% N-methyl-substituted diaminodiphenylmethanes
20.5% triamines
7.7% tetramines
6.6% polyamines of higher than tetrafunctionality
EXAMPLE 3 (FIG. 1)
In a reactor (3) consisting of two stirred tanks arranged one after the other, a 30% aqueous formalin solution (product stream (A)) is reacted at 40° C. with an aniline-xylene mixture (product stream (B)).
(A) 0.500 kg/h formaldehyde
1.166 kg/h water
(B) 3.103 kg/h aniline
2.586 kg/h o-xylene
In a water separator (4), the lower aqueous phase is separated as wastewater and collected in a wastewater tank (13). The upper organic phase is transferred to a second reactor (5) consisting of three stirred tanks in which the organic phase is mixed with the product stream (C).
(C) 0.924 kg/h polyarylamine
1.000 kg/h aniline
0.437 kg/h hydrochloric acid
2.634 kg/h water
The temperatures in the three tanks of the reactor (5) are regulated at, in sequence, 35° C., 50° C., and 60° C.
Another reactor (6) likewise consists of three stirred tanks in which the temperatures are regulated by heating at 100° C., 135° C., and 140° C. at the intrinsic pressure of the system.
After the reaction mixture cools to 95° C. and expands to normal pressure, the organic phase (product stream (E)) and the aqueous phase (product stream (F)) are then separated from each other in the phase separator (7). The HCl wash water from the washing stage (12) (product stream (D)) is then added to the aqueous phase (F).
(E) 0.910 kg/h polyarylamine
1.187 kg/h aniline
2.586 kg/h o-xylene
(F) 2.844 kg/h polyarylamine
0.286 kg/h aniline
0.437 kg/h hydrochloric acid
2.634 kg/h water
The aqueous phase (F) is then continuously extracted by countercurrent extraction with an aniline-xylene mixture (product stream (G)) in the extraction column (8)
(G) 0.048 kg/h polyarylamine
5.592 kg/h aniline
5.523 kg/h o-xylene
changing into the polyarylamine-depleted aqueous phase (H)
(H) 0.062 kg/h polyarylamine
1.823 kg/h aniline
0.437 kg/h hydrochloric acid
3.841 kg/h water
which is used in another extraction column (9) for the countercurrent extraction of the organic phase (E) separated in phase separator (7).
The aqueous phase (product stream (1)) that accumulates in (9), which is enriched with polyarylamine in relation to the aqueous phase (H),
(I) 0.924 kg/h polyarylamine
1.000 kg/h aniline
0.437 kg/h hydrochloric acid
3.841 kg/h water
is concentrated in the distillation stage (10), with concomitant removal of the distillate as product stream (K), and is then returned to the reactor (5) as product stream (C).
(K) 1.207 g/h water
The organic phase that accumulates in extraction stage (9), in which the polyarylamine content is depleted relative to (E), is used as the product stream (L) component of extractant in product extraction stage (8). Product stream (L) and the aniline-xylene mixture (M) together constitute product stream (G), which forms the total quantity of extractant used in product extraction stage (8).
(L) 0.048 kg/h polyarylamine
2.060 kg/h aniline
2.586 kg/h o-xylene
(M) 3.532 kg/h aniline
2.037 kg/h o-xylene
The organic phase containing the reaction product which accumulates in the product extraction stage (8) (product stream (N)) is extracted in another three- to five-stage extraction column (washing stage (12)), with the distillate from distillation stage (10) consisting essentially of water (product stream (K)).
(N) 2.830 kg/h polyarylamine
4.005 kg/h aniline
5.523 kg/h o-xylene
(K) 1.207 kg/h water
In the washing stage (12), the HCl content of the product stream (N), which amounts to about 0.2-0.3% by weight, is reduced under the described conditions to less than 0.01% by weight. The HCl-containing wash water is recycled into the reaction mixture as product stream (D). The organic phase leaving the washing stage (12) is separated in a distillation stage (11) into a distillate (product stream (O)) and a distillation residue (product stream (P)).
(O) 4.005 kg/h aniline
5.523 kg/h o-xylene
(P) 2.830 kg/h polyarylamine
After addition of fresh aniline (product stream (Q)) from storage tank (2) to product stream (O), the aniline-xylene mixture thus prepared (product stream (R)) is divided and used as product streams (B) and (M).
The distillation residue (product stream (P)) of the distillation stage (11) has the following composition:
0.3% 2,2'-diaminodiphenylmethane
4.4% 2,4'-diaminodiphenylmethane
50.5% 4,4'-diaminodiphenylmethane
0.2% N-methyl-substituted diaminodiphenylmethanes
20.7% triamines
10.1% tetramines
13.8% polyamines of higher than tetrafunctionality
Although the invention has been described in detail in the foregoing for the purpose of illustration, it is to be understood that such detail is solely for that purpose and that variations can be made therein by those skilled in the art without departing from the spirit and scope of the invention except as it may be limited by the claims. | This invention relates to an improved process for the preparation of polynuclear aromatic polyamines in which the reaction product is prepared by condensing aniline with formaldehyde in the presence of water and acidic catalysts and is worked up by extraction with a hydrophobic solvent. The acid catalyst that accumulates in the aqueous phase during the extraction process is reused. | 2 |
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